High susceptibility to lung cancer analyzed in terms of combined genotypes of P450IA1 and Mu-class glutathione S-transferase genes. Lung cancer is closely associated with cigarette smoking. Aromatic hydrocarbons in smoke, including benzo[a]pyrene, first require metabolic activation by Phase I enzymes, cytochrome P450, to their ultimate forms, and these activated forms are then subjected to detoxification by Phase II enzymes, especially glutathione S-transferases. Thus, genetically determined susceptibility to lung cancer may depend on the metabolic balance between Phase I and Phase II enzymes. In this study, we identified individuals genetically at high risk of lung cancer in terms of polymorphisms of the P450IA1 gene and GST1 gene. The relative risk of individuals with a combination of the genotypes of both a homozygous rare allele of the P450IA1 gene and the nulled GST1 gene was remarkably high at 5.8 for lung cancer and 9.1 for squamous cell carcinoma compared with other combinations of genotypes.


Deficiency of beta 1-6 N-acetylglucosaminyltransferase involved in the biosynthesis of blood group I antigen in the liver of LEC rats. The activities of the beta 1-6 and beta 1-3 N-acetylglucosaminyltransferase, which synthesize blood group I and i antigens, respectively, were measured in various tissues of hepatitis- and hepatoma-predisposed rats (LEC rats). In LEC rats the beta 1-6 N-acetylglucosaminyltransferase activity was barely detectable in the liver, while substantial enzyme activity was found in other tissues. In the control LEA rats the enzyme was expressed in most tissues, including the liver. Immunochemical studies using a monoclonal antibody which recognizes I antigen indicated that the expression of I antigen was less prominent in hepatocytes of LEC rats than in hepatocytes of LEA rats. The level of beta 1-3 N-acetylglucosaminyltransferase activity was constant in most of the tissues during the development. These results indicate that the biosynthesis of I antigen does not occur in the livers of the LEC rats.


Production of human immunoglobulin G reactive against human cancer in tumor-bearing mice with severe combined immunodeficiency reconstituted with human splenic tissues. Splenic tissues derived from patients with gastric cancer were implanted into mice with severe combined immunodeficiency (SCID) and then the mice were challenged with COLO-205, a human colon cancer cell line. Production of human immunoglobulin G (IgG) reactive against the COLO-205 cells was detected by enzyme-linked immunosorbent assay in sera from the reconstituted and tumor-bearing SCID mice. The titers of the reactive IgG relative to total IgG in the sera of SCID mice began to increase from one week after implantation of the tumor cells, and became 10- to 100-fold higher than that in the donor's serum by 3-4 weeks. This model using implantation of human cancer cells in SCID mice reconstituted with human splenic tissues would facilitate further studies of human cancer immunology.


Triflavin, an Arg-Gly-Asp-containing antiplatelet peptide inhibits cell-substratum adhesion and melanoma cell-induced lung colonization. Triflavin, an Arg-Gly-Asp (RGD) containing peptide purified from Trimeresurus flavoviridis snake venom, inhibits human platelet aggregation by blocking fibrinogen binding to fibrinogen receptors associated with glycoprotein IIb/IIIa complex. In this study, we show that triflavin (1-30 micrograms/mouse) inhibits B16-F10 melanoma cell-induced lung colonization in C57BL/6 mice in a dose-dependent manner. In vitro, triflavin dose-dependently inhibits adhesion of B16-F10 melanoma cells to extracellular matrices (ECMs; i.e., fibronectin, fibrinogen, vitronectin, and collagen type I). Triflavin is approximately 600-800 times more potent than GRGDS at inhibiting cell adhesion. In addition, triflavin dose-dependently inhibits B16-F10 cell-induced platelet aggregation. These results imply that the inhibitory effect of triflavin on the adhesion of tumor cells to ECMs (e.g., fibronectin, vitronectin and collagen type I) and/or tumor cell-induced platelet aggregation may be partially responsible for its antimetastatic activity in C57BL/6 mice.


Polyoxyethylene-modified superoxide dismutase reduces side effects of adriamycin and mitomycin C. Polyoxyethylene-modified superoxide dismutase (SOD-POE) is a newly developed long-acting superoxide dismutase. Adriamycin (ADR) and mitomycin C (MMC) generate superoxide, which contributes to their cytocidal effects or side effects. We examined whether SOD-POE could prevent the side effects induced by superoxide generated by antitumor agents, and the following results were obtained. SOD-POE did not influence the antitumor effects of ADR and MMC either in vitro or in vivo, but prevented the toxic death of BALB/c, nu/nu male mice caused by overdoses of ADR or MMC. As for its effective sites, SOD-POE prevented a decrease in the specific activity of rotenone-sensitive NADH-ubiquinone oxido-reductase (complex I) in heart muscle mitochondrial respiratory chain function in BALB/c male mice administered 10 mg/kg ADR, and prevented damage to the sarcoplasmic reticulum and mitochondria of mouse heart muscle by ADR as observed by electron microscopy. Furthermore, SOD-POE prevented bone marrow suppression induced by MMC in Donryu rats. The above results suggest that combination chemotherapy with SOD-POE would make it possible to increase the maximum permissible doses of antitumor agents, improving the efficacy of these agents.


Potentiation of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea's toxicity in vitro by two new bioreductive agents. Two new bioreductive compounds, 9-[3-(2-nitro-1-imidazolyl)propylamino]acridine hydrochloride (NLA-1) and 9-[2-(2-nitro-1-imidazolyl)ethylamino]acridine hydrochloride (NLA-2), which behave as hypoxic cytotoxins and radiosensitizers, have been investigated for potentiation of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea's (CCNU) cytotoxic activity in vitro using V-79 cells. The preincubation effect as well as conditions of coadministration of CCNU with each sensitizer have been examined. In this latter case, the median-effect analysis was applied to evaluate whether the phenomenon was additive or synergistic. A clonogenic assay was used to score survival. Both bioreductive compounds, even at very low concentrations, significantly enhance the cytotoxic activity of CCNU under conditions of hypoxic preincubation. The enhancement of CCNU cytotoxicity is dependent upon preincubation time and the concentrations of both CCNU and the specific bioreductive agent. Coincubation of cells under hypoxia with CCNU and each bioreductive agent led to some potentiation, but only at lower survival levels. No chemosensitization was observed under aerobic conditions with either sensitizer.


Polyamines in ejaculated ram spermatozoa and their relationship with sperm motility. Intracellular polyamine levels in ejaculated spermatozoa and seminal fluid from rams were determined by fluorescent spectroscopy of their dansyl derivatives. Relationships between the sperm polyamine content and sperm motility of six mature and eight pubescent rams were studied. Samples were collected from both groups once a month from August through October. Mature rams had a greater percentage of motile sperm cells than lambs (94% versus 73% in September and 92% versus 78% in October); higher spermidine content (36 versus 9 pmol/10(8) cells in September and 162 versus 55 pmol/10(8) cells in October); higher spermine content (984 versus 205 pmol/10(8) cells in September and 1,229 versus 414 pmol/10(8) cells in October); and higher total sperm polyamine content (1,021 versus 216 pmol/10(8) cells in September and 2,258 versus 973 pmol/10(8) cells in October). In the lambs, spermidine content increased (55 versus 9 pmol/10(8) cells); spermine content increased (414 versus 205 pmol/10(8) cells); and total sperm polyamine content increased (973 versus 215 pmol/10(8) cells) in October compared to September. Ejaculates with sperm motility higher than 85% had greater spermine (848 versus 234 pmol/10(8) cells in September and 1064 versus 449 pmol/10(8) cells in October), and total sperm polyamine content (882 versus 244 pmol/10(8) cells in September and 2,015 versus 1,008 pmol/10(8) cells in October) than ejaculates with less than 450 pmol total sperm polyamines/10(8) cells was 68% +/- 6% compared to 90% +/- 4% in cells with greater than 450 pmol (average for all ejaculates) total sperm polyamines/10(8) cells. These data suggest a positive relationship between sperm polyamine constant and sperm motility.(ABSTRACT TRUNCATED AT 250 WORDS)


A long-term, prospective study of the physiologic and behavioral effects of hormone replacement in untreated hypogonadal men. This study describes sexual activity, nocturnal penile erections, and mood states as a function of serum levels of androgens in previously untreated hypogonadal men before and during hormone replacement, selected infertile men (elevated serum follicle-stimulating hormone levels), and normal men. Nocturnal penile tumescence and rigidity were measured with a portable monitor, and sexual activity and mood were assessed by prospective, self-reported written forms. Nocturnal erections were absent or of very low amplitude and duration in the untreated hypogonadal men compared to the infertile and normal men. Nocturnal erections increased steadily during hormone replacement and were in the normal range within 6 to 12 months of treatment. In contrast, serum testosterone concentration rapidly reached the upper range of normal. During treatment, the hypogonadal men reported increases in several aspects of sexual activity, including sexual interest and the number of spontaneous erections. On mood inventories, the untreated hypogonadal men scored significantly higher in ratings of depression, anger, fatigue, and confusion than did infertile and normal men. During hormonal replacement therapy these scores decreased, although the hypogonadal men continued to score higher in "depression" than did infertile and normal men. In most instances, the men with infertility and the normal men were statistically indistinguishable in nocturnal penile tumescence and rigidity parameters, self-reported sexual activity, and mood state. These data support the hypothesis that androgen treatment increases nocturnal and spontaneous erections, and sexual interest, and has some capacity to improve mood.


Developmental expression of multiple forms of 3-hydroxy-3-methylglutaryl coenzyme A reductase mRNA in rat testes. The developmental expression of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the enzyme that catalyzes the rate-limiting reaction of mevalonate formation, was investigated in rat testes. Adult testes were found to contain three distinct forms of HMG-CoA reductase mRNA of 4.8, 4.2, and 4.0 kilobases (kb) in length. In testes from 26-day-old rats the 4.8-kb species was the major form present. By 40 days of age, large increases in the levels of the testes-specific 4.2- and 4.0-kb forms occurred, with a small decrease in the amount of the 4.8-kb form. The level of the 4.8-kb form appeared to be associated with the level of testicular HMG-CoA reductase activity.


Folipastatin, a new depsidone compound from Aspergillus unguis as an inhibitor of phospholipase A2. Taxonomy, fermentation, isolation, structure determination and biological properties. A new inhibitor of phospholipase A2 was isolated from the fermentation broth of Aspergillus unguis. The structure, with a depsidone carbon skeleton, was assigned by spectroscopic experiments.


Hyperactivated motility is coupled with interdependent modifications at axonemal and cytosolic levels in human spermatozoa. Whether the motility characteristics of hyperactivated spermatozoa were determined by stable changes at the axonemal level and whether the presence of cytosolic factors was required for the expression of these changes was investigated. Different degrees of sperm hyperactivation were produced in Percoll-washed spermatozoa after incubation for 1 hour to 3 hours at 37 degrees C in Ham's F-10 supplemented with human blood plasma or fetal cord serum. Decomplemented fetal cord serum induced the highest percentage of hyperactivation (19 +/- 3%), followed by human plasma (13 +/- 2%). Fetal cord serum that was not decomplemented did not induce a level of hyperactivation (1.7 +/- 0.2%) significantly different from control levels (0.9 +/- 0.2%). Dialyzed fetal cord serum induced intermediate levels of hyperactivation (6 +/- 1%). The motility characteristics of demembranated sperm models of hyperactivated spermatozoa induced by decomplemented fetal cord serum and nonhyperactivated spermatozoa were compared by videomicroscopy and computer-assisted digital image analysis. After demembranation with Triton X-100 and reactivation of motility by Mg. adenosine triphosphate (Mg.ATP), hyperactivated and nonhyperactivated spermatozoa showed similar motility characteristics. However, hyperactivated spermatozoa that were demembranated and reactivated in cytosolic extracts from hyperactivated spermatozoa had significantly higher (P less than 0.05) linear velocity (33 +/- 4 mu/sec) and lower linearity (0.23 +/- 0.04) than control spermatozoa that were demembranated and reactivated in control cytosolic extracts (velocity = 24 +/- 1 mu/sec; linearity = 0.32 +/- 0.02). The data suggest that the expression of hyperactivated motility requires interdependent changes at the axonemal and cytosolic levels.(ABSTRACT TRUNCATED AT 250 WORDS)


Glisoprenins, new inhibitors of acyl-CoA: cholesterol acyltransferase produced by Gliocladium sp. FO-1513. I. Production, isolation and physico-chemical and biological properties. Gliocladium sp. FO-1513 was found to produce novel inhibitors of acyl-CoA: cholesterol acyltransferase (ACAT). Two active compounds, designated glisoprenins A and B, were isolated from the culture broth of the producing strain by a conventional method. The IC50 values of glisoprenins A and B for ACAT activity were 46 and 61 microM in an enzyme assay using rat liver microsomes, and 1.2 and 0.57 microM in a J774 macrophage assay, respectively.


Adenosine triphosphate (ATP) concentrations and ATP/adenosine diphosphate ratios in human sperm of normospermic, oligospermic, and asthenospermic specimens and in their swim-up fractions: lack of correlation between ATP parameters and sperm creatine kinase concentrations. The authors had previously found an inverse correlation between per sperm creatine phosphokinase activity and sperm concentrations in men. Because creatine phosphokinase is a key enzyme in sperm energy transport, the possible relationship of sperm creatine phosphokinase activity, sperm adenosine triphosphate (ATP) concentrations, sperm ATP/ADP (adenosine diphosphate) ratios, and computer-aided semen analysis sperm motility parameters were then studied. The ATP concentrations and ATP/ADP ratios, measured by high-pressure liquid chromatography in washed sperm, were similar in normospermic and oligospermic specimens (ATP: 123.1 +/- 21.6 vs. 90.0 +/- 24.5 pmol/10(6) sperm; ATP/ADP: 2.8 +/- 0.4 vs. 2.1 +/- 0.4, N = 32 and 17, mean +/- SEM), and in samples with normal and less than 40% sperm motility (ATP: 96.8 +/- 27.2 vs. 122.2 +/- 19.6 pmol/10(6) sperm; ATP/ADP: 2.4 +/- 0.5 vs. 2.8 +/- 0.4, n = 26 and 23). In the swim-up sperm fractions, which showed improved motility, the ATP concentrations, but not the ATP/ADP ratios, were lower than in the initial semen samples (ATP: 152.9 +/- 28.4 vs. 90.3 +/- 10.6 pmol/10(6) sperm, P less than 0.05; ATP/ADP: 3.3 +/- 0.5 vs. 3.9 +/- 0.7, N = 18 pairs of samples). This is consistent with our previous finding of a lower cytoplasmic content in sperm in swim-up fractions.(ABSTRACT TRUNCATED AT 250 WORDS)


Changes in the hypothalamic-pituitary-gonadal axis in men after cadaver kidney transplantation and cyclosporine therapy. A variety of plasma androgens, estradiol, follicle-stimulating hormone, luteinizing hormone, prolactin, cortisol, and thyroid parameters were examined in 10 men followed serially before and after cadaver kidney transplantation. Before transplantation, plasma testosterone levels were below normal in 8 of the 10 men. Free testosterone, follicle-stimulating hormone, and luteinizing hormone were at the lower range of normal values, yet plasma estradiol levels were elevated 3-fold, and prolactin levels were also high. One month after transplantation, all hormones measured were suppressed, probably reflecting high-dose steroids and multiple-drug regimens used in the period following the operation. After 3 months, when other immunosuppressants were reduced and cyclosporine dosage was stabilized, plasma testosterone, androgens, follicle-stimulating hormone, and luteinizing hormone levels were restored toward normal. After 12 months, plasma testosterone levels exceeded pretransplant levels. Plasma estradiol and prolactin levels dramatically decreased after transplantation and remained in the normal range thereafter. These data indicate that abnormalities of plasma estradiol and prolactin levels observed in patients with end-stage renal disease are restored toward normal after cadaver kidney transplantation. Androgen levels that were suppressed in the period immediately after transplantation were restored to normal levels in the succeeding months despite chronic usage of cyclosporine, suggesting that cyclosporine, in currently used doses, does not prevent the restoration of the hypothalamic-pituitary-testicular axis.


New cyclodepsipeptides, enniatins D, E and F produced by Fusarium sp. FO-1305. New cyclodepsipeptides named enniatins D, E and F were isolated from the culture broth of Fusarium sp. FO-1305 as inhibitors of acyl-CoA:cholesterol acyltransferase (ACAT). The respective structures of enniatins D, E and F were determined to be cyclo[D-alpha-hydroxyisovaleryl(D-Hiv)-L-N-methylleucinyl(L- Me-Leu)-D-Hiv-L-N-methylvalinyl(L-Me-Val)-D-Hiv-L-Me-Val], a mixture of cyclo-[D-Hiv-L-Me-Leu-D-Hiv-L-N-methylisoleucinyl(L-Me-Ile)-D-Hiv- L-Me-Val] and cyclo(D-Hiv-L-Me-Ile-D-Hiv-L-Me-Leu-D-Hiv-L-Me-Val), and cyclo(D-Hiv-L-Me-Leu-D-Hiv-L-Me-Ile-D-Hiv-L-Me-Ile) by spectral analyses and chemical degradation. The IC50 values of enniatins D, E and F for ACAT activity in an enzyme assay using rat liver microsomes were calculated to be 87, 57 and 40 microM, respectively.


Oligotriche and quaking gene mutations. Phenotypic effects on mouse spermatogenesis and testicular steroidogenesis. The phenotypic actions of the oligotriche gene mutation on testicular function have not been elucidated, although it is known that male mice homozygous for the mutation are infertile. In the present study, the effect of the oligotriche gene mutation on mouse testicular function was analyzed by comparing normal and mutant mice. Spermatogenesis was analyzed by enumerating germ cells in seminiferous tubules at specific stages of spermatogenesis and by electron microscopy. Steroidogenic potential was estimated by radioimmunometric determination of testosterone secreted by testes perfused in vitro. Parallel studies were completed for male mice homozygous for the quaking gene mutation, a mutation known to cause male mouse sterility by disrupting sperm tail development. The experimental results suggest that the oligotriche and quaking gene mutations interfere with sperm tail formation by different mechanisms. Testicular steroidogenesis was not affected by either gene mutation. The results provide the first evidence that the oligotriche gene mutation induces male mouse sterility by effecting the complete absence of a sperm tail. This phenotypic action is different from that of the quaking gene mutation.


Diffuse lymphoid tissue associated with the human bulbourethral gland. An immunohistologic characterization. This study investigates the presence and distribution of immunocompetent cells in bulbourethral glands obtained from four multiorgan transplant donors. Monoclonal antibodies reacting with B (Leu 12+) and T (Leu 4+) cells, suppressor-cytotoxic cells (Leu 2+), helper-inducer (Leu 3a+) and natural killer (Leu7+) phenotypes, monocyte-macrophages, (LeuM3+), and cells expressing interleukin-2 receptor and HLA-DR antigen were tested in all specimens using an indirect immunoperoxidase staining procedure. T lymphocytes were estimated to represent 10% of the mucosal cell population. Almost all intraepithelial lymphocytes were suppressor-cytotoxic (CD8+) cells. The results demonstrate the presence of a defined distribution of immunocompetent cells in these sex accessory glands. Their role in combatting infections or other chronic genitourinary diseases is still undefined.


Acaterin, a novel inhibitor of acyl-CoA: cholesterol acyltransferase produced by Pseudomonas sp. A92. Acaterin, a novel inhibitor of acyl-CoA: cholesterol acyltransferase (ACAT), was isolated from a culture broth of Pseudomonas sp. A92 by Diaion HP-20 column chromatography, solvent extraction and reverse phase HPLC. Spectroscopic analyses of the compound yielded 3-(1-hydroxyoctyl)-5-methyl-2(5H)-furanone as the proposed structure. In the presence of oxidized low density lipoprotein, acaterin inhibited the synthesis of cholesteryl ester in macrophage J774 by 50% at a concentration of 45 microM. Acaterin also inhibited ACAT activity in the rat liver microsomes by 50% at a concentration of 120 microM. Kinetic studies suggested that inhibition of ACAT by acaterin was noncompetitive with respect to oleoyl-CoA.


A10255, a complex of novel growth-promoting thiopeptide antibiotics produced by a strain of Streptomyces gardneri. Taxonomy and fermentation studies. A10255 is a complex of new thiopeptide antibiotics characterized structurally by a cyclic peptide core to which is attached a side chain composed of dehydroalanine moieties. The complex contained 80-85% factor B, 15-20% factor G, and trace amounts of factors C, D, E, F, H, and J. Taxonomic studies indicated the producing microorganism to be a strain of Streptomyces gardneri. The major portion of the antibiotic produced remained associated with the mycelial biomass, from which it was extracted with polar solvents such as aqueous methanol or aqueous acetone. Initial A10255 yields of < 2 micrograms/ml were increased to over 300 micrograms/ml in stirred reactors through strain selection, nutritional studies, and conversion of the batch fermentation to a fed-batch mode.


Thiol-disulfide status and acridine orange fluorescence of mammalian sperm nuclei. The relationship between thiol-disulfide status and acridine orange fluorescence of testicular, epididymal, and ejaculated spermatozoa in several mammalian species was investigated. Spermatozoa were fixed with acetic alcohol, stained with acridine orange, and examined with a fluorescence microscope. The majority of the nuclei of testicular spermatozoa of the hamster, mouse, and rabbit exhibited red acridine orange fluorescence. The proportion of sperm nuclei with red acridine orange fluorescence decreased as the spermatozoa descended the epididymis. Red acridine orange fluorescence was replaced by green acridine orange fluorescence. The site in the epididymis where 100% of the nuclei exhibited green fluorescence was the distal caput in the mouse, the corpus in the rabbit, and the proximal cauda in the hamster. In semen samples from men with proven fertility, normal semen parameters, or both, about 60% to 90% of the nuclei exhibited green acridine orange fluorescence. The proportion of sperm nuclei exhibiting green acridine orange fluorescence was higher in the spermatozoa pellet (containing highly motile spermatozoa) obtained by centrifugation through a Percoll gradient. From experiments using disulfide-reducing, thiol-oxidizing and thiol-detecting agents, we concluded that sperm nuclei fluoresce red when they are treated with acid while their DNA-associated protamines are poor in disulfides. Under such conditions, DNA is vulnerable to denaturation. Acridine orange binds to denatured (single-stranded) DNA as aggregates and emits red fluorescence. In contrast, when sperm nuclei are treated with acid while their DNA-associated protamines are rich in disulfides, DNA is resistant to denaturation. Acridine orange binds to native (double-stranded) DNA as a monomer and emits green fluorescence.(ABSTRACT TRUNCATED AT 250 WORDS)


Isolation and structure elucidation of new antibiotics related to angolamycin. Angolamycin (1) and two novel analogues (2 and 3) were isolated from the culture broth of a Streptomyces strain. NMR and MS analysis proved that 2 is the 18-dihydro-, while 3 is the 18-deoxo-18-dihydro derivative of angolamycin. Full experimental assignment of the 1H and the 13C NMR spectra of these compounds was obtained from 1D and 2D chemical shift correlation measurements. Compounds 2 and 3 are less potent antibiotics than angolamycin.


Sultriecin, a new antifungal and antitumor antibiotic from Streptomyces roseiscleroticus. Production, isolation, structure and biological activity. Streptomyces roseiscleroticus L827-7 (ATCC 53903) produced a novel antifungal and antitumor antibiotic, sultriecin. It exhibited in vitro antifungal activity and potent in vivo antitumor activity against P388 and L1210 leukemias, and B16 melanoma. Sultriecin is composed of several unique structural units; a conjugated triene, an alpha,beta-unsaturated delta-lactone, and a sulfate functionality.


Kedarcidin, a new chromoprotein antitumor antibiotic. II. Isolation, purification and physico-chemical properties. Kedarcidin, a new chromoprotein antitumor antibiotic, was isolated from the culture broth of a novel actinomycete strain L585-6 (ATCC 53650). The antibiotic was recovered from the culture filtrate by adsorption to QAE ion exchanger and purified by successive application of gel filtration and ion exchange chromatography with Sephadex G-50 and DEAE-Sephadex, respectively. Kedarcidin is an acidic complex (pI 3.65) with an apparent molecular weight of 12,400. The complex consists of a highly unstable, solvent extractable chromophore and a water soluble peptide. The apoprotein is a single chain polypeptide of 114 residues.


Anthracycline metabolites from baumycin-producing Streptomyces sp. D788. I. Isolation of antibiotic-blocked mutants and their characterization. Biosynthetically blocked mutants were obtained from a baumycin-producing Streptomyces sp. D788 newly isolated from soil. The first mutant isolated was a baumycin-negative but daunorubicin-accumulating mutant with a loss of 4'-substitution activity, from which all other blocked mutants were successively derived. These included a known 11-deoxydaunorubicin-producing mutant and several new types of mutants which produced mainly 10-carboxy-13-deoxocarminomycin, 10-methoxycarbonyl-13-deoxocarminomycin, their 11-deoxy derivatives or a precursor aglycone, respectively. In this paper, all the anthracycline components produced by the parent strain and its two known blocked mutants, a daunorubicin producer and a 11-deoxydaunorubicin producer, are also determined by HPLC and five new components are isolated. Cytotoxicities in vitro of all the components against L1210 cell culture are also described.


Vermixocins A and B, two novel metabolites from Penicillium vermiculatum. Vermixocins A and B, 3-(1'-hydroxy-3'-methylbutyl)- and 3-(1'-acetoxy-3'-methylbutyl)-11-hydroxy-4-methoxy-9-methyl-5H,7H- dibenzo[c,f][1,5]dioxocin-5-one, respectively, were isolated from the mycelium of Penicillium vermiculatum. Both metabolites showed cytotoxic effects on lympholeukemia cells P388.


Enniatin synthetases from different fusaria exhibiting distinct amino acid specificities. Enniatin synthetases from the cyclodepsipeptide producers Fusarium lateritium and Fusarium sambucinum were purified to homogeneity and characterized. Like the previously described enniatin synthetase from Fusarium scirpi both enzymes consist of a single polypeptide chain and are very similar concerning their Mr (250 kdaltons) and reaction mechanism. Limited proteolytic digests show only slight differences in their patterns in SDS-gels. Interestingly the synthetases differ in their amino acids specificities. The enzyme from the enniatin A producer F. sambucinum exhibits a high affinity to the substrate amino acids L-Leu and L-Ile. In contrast the synthetase from the enniatin B producer F. lateritium preferably accepts L-Val, the constituent amino acid of enniatin B.


Biosynthesis of thiopeptide antibiotic A10255 in stirred reactors using a chemically defined medium supplemented with continuous nutrient feeds. A10255 is a complex of new thiopeptide antibiotics produced by Streptomyces gardneri. When stirred reactors were operated in batch mode using a defined medium with a glucose feed, 250 micrograms/ml of A10255 were produced during a four-day fermentation cycle. The linear growth phase of S. gardneri was extended through seven days by supplementing the defined medium with continuous feeds of hydrolyzed casein and methyl caprate. With the supplementary feeds, antibiotic biosynthesis paralleled growth during the extended cycle and attained levels of 1,750 micrograms/ml. Increasing the standard glucose feed rate increased titers principally by increasing cell mass. Supplementing the standard glucose feed with lipids such as caprylate or caprate, and decyl alcohol, affected cell mass minimally but produced higher titers by increasing the specific biosynthesis of A10255 per unit of biomass.


Cloning of aklavinone biosynthesis genes from Streptomyces galilaeus. Aklavinone is an aglycone of aclacinomycin A which is an important antitumor drug. Genes for the biosynthesis of aklavinone were cloned from Streptomyces galilaeus 3AR-33, an aklavinone-producing mutant, by use of the actI and actIII polyketide synthase gene probes. Restriction mapping and Southern analysis of the DNA cloned in a lambda phage vector established that the DNA represented three different regions of the S. galilaeus 3AR-33 genome that contained 3.4, 2.5, and 4.1 kb BamHI fragments which hybridized with actIII. Of those, only the 3.4 kb fragment also hybridized with actI. Complementation experiments with specifically blocked mutants confirmed that the cloned 3.4 kb BamHI fragment contains the genes required for the early stage of polyketide synthesis in aklavinone biosynthesis.


Immunomodulating properties of prodigiosin 25-C, an antibiotic which preferentially suppresses induction of cytotoxic T cells. An antibiotic, prodigiosin 25-C, preferentially suppresses cytotoxic T lymphocytes (CTL) without affecting antibody production. Here, we investigated the effect of prodigiosin 25-C on delayed-type hypersensitivity (DTH), graft versus host reaction (GvHR) and allogeneic skin graft rejection. DTH reactions were markedly inhibited by ip treatment of the mice with prodigiosin 25-C. Cell transfer experiments indicated that prodigiosin 25-C exerted its suppressive effect on the late efferent phase rather than on the induction phase of DTH. Prodigiosin 25-C suppressed induction of anti-host CTL when GvHR was induced by iv inoculating splenocytes of parental C57BL/6 mice to adult unirradiated BDF1 mice. It had little effect on GvHR-induced splenomegaly observed 2 weeks after the inoculation, but significantly delayed the subsidence of splenomegaly as revealed 8 weeks later, suggesting that suppression of CTL converts immunosuppressive GvHR to immunostimulative one as reported by G. M. Shearer. However, reduction of interleukin-2 (IL-2) production and mitogen responses induced by GvHR were not rescued by prodigiosin 25-C treatment. Prodigiosin 25-C moderately prolonged survival of major histocompatibility (MHC)-mismatched skin grafts. Since the mode of action of prodigiosin 25-C is distinct from those of cyclosporin A and FK506, these results demonstrate potential usefulness of the antibiotic for a supplementary immunosuppressant.


Enhancement by concanavalin A of the suppressive effect of prodigiosin 25-C on proliferation of murine splenocytes. Proliferation of concanavalin A (Con A)-activated nylon-wool purified murine splenic T cells was increasingly suppressed by prodigiosin 25-C as higher concentrations of Con A were used for the activation. Enhancement of suppressive effect of prodigiosin 25-C was not observed when T cells were stimulated with phytohemagglutinin (PHA), anti-CD3 antibody, or allogeneic splenic adherent cells. The suppressive effect of prodigiosin 25-C was enhanced by the addition of Con A in various T cell subpopulations as well as in LPS-activated splenic B cells. Lectins that recognize mannose residue of biantennary-complex-type sugar chains significantly enhanced the suppressive effect of prodigiosin 25-C, whereas a lectin that binds to N-acetylglucosamine did not. These results suggest that binding of lectins to the mannose residue of biantennary-complex-type sugar chains on cell surface of both T and B lymphocytes plays a central role on the enhancement of the suppressive effect of prodigiosin 25-C.


Protorubradirin, an antibiotic containing a C-nitroso-sugar fragment, is the true secondary metabolite produced by Streptomyces achromogenes var. rubradiris. Rubradirin, described earlier, is its photo-oxidation product. In an attempt to improve the isolation of the antibiotic rubradirin from fermentations of Streptomyces achromogenes var. rubradiris, the use of preparative reversed-phase chromatography was investigated. The product isolated was a mixture of rubradirin and a new antibiotic named protorubradirin, of extremely similar structure, which is converted into rubradirin on exposure to light and air. Methanolysis of protorubradirin in the dark yields an anomeric mixture of methyl glycosides of a C-nitroso-sugar, converted photo-oxidatively into the methyl rubranitrosides derived from rubradirin. Thus, protorubradirin is the C-nitroso-analogue of rubradirin. It is suggested that the same relationship between protorubradirin and rubradirin may apply to the anthracycline antibiotics viriplanin A and viriplanin D.


Structural characterization of bacitracin components by Frit-fast atom bombardment (FAB) liquid chromatography/mass spectrometry (LC/MS). The structural characterization of minor components of bacitracin (BC) complex was carried out using a technique of liquid chromatography/mass spectrometry (LC/MS). Satisfactory total ion current chromatogram of BC complex and excellent mass spectra of many components were given by Frit-fast atom bombardment (FAB) LC/MS analytical system, and the structures of 13 minor components could be proposed. The 13 minor components were classified into two groups, bacitracin A (BC-A) related components and bacitracin F (BC-F) related components depending on their common N-terminal moieties. The structures of BC-A related components and BC-F related components were the same as those of BC-A and BC-F, respectively, except that one to three of isoleucine and leucine residues are replaced by valines. The BC-F related components were degradation products of BC-A related components through the same degradation process as that of BC-A.


Cefclidin (E1040), a novel cephalosporin: lack of selection of beta-lactamase overproducing mutants in an in vitro pharmacokinetic model system. The bactericidal activity of cefclidin (E1040), a new cephalosporin, against a clinical strain of Citrobacter freundii was compared with that of ceftazidime in a two-compartment in vitro pharmacokinetic model system designed to simulate plasma concentrations in humans for 12 hours after intravenous administration of a 1 g dose. Both cefclidin and ceftazidime showed rapid bactericidal activity against C. freundii. However, during the simulation of ceftazidime treatment, regrowth was observed after two hours and a subpopulation emerged which was resistant to ceftazidime. Neither regrowth nor the emergence of resistant mutants was observed with cefclidin during the 12-hour simulation. The ceftazidime-resistant mutants constitutively overproduced beta-lactamase at levels which were about 500-fold higher than that of the parent wild-type strain. Against this beta-lactamase overproducing mutant, no bactericidal activity of ceftazidime was observed in the in vitro model system, whereas the bactericidal activity of cefclidin was observed during the 12-hour period. The emergence of Enterobacter cloacae mutants derepressed for beta-lactamase production was also observed with ceftazidime but not cefclidin. The affinity of cefclidin for the beta-lactamase isolated from these mutants was lower than that of ceftazidime, and the kinetic parameters of enzymatic hydrolysis showed that cefclidin was hydrolyzed more slowly at a low concentration (0.2 microM) than was ceftazidime. It is suggested that the high activity of cefclidin against strains derepressed for beta-lactamase plays a major role in the absence of emergence of resistant mutants.


Structure-binding relationship and binding sites of cephalosporins in human serum albumin. The binding of some cephalosporins to human serum albumin (HSA) was studied by an ultrafiltration technique. Changes in C-3 side chain resulted in marked changes in the binding to HSA, but changes in C-7 side chain did not. Cephalosporins were classified into three groups by C-3 side chain: (i) Cationic side chain with low affinity for HSA; (ii) anionic side chain with high affinity for HSA; (iii) non ionized side chain, in which binding to HSA was dependent on lipophilicity. These findings suggest that electrostatic and hydrophobic forces play a role in the binding affinity of cephalosporins for HSA. The binding of cephalosporins with high HSA affinity was displaced significantly by warfarin but not by phenylbutazone, L-tryptophan, or diazepam. The interaction of the cephalosporins with high affinity for HSA with chemically modified HSA was investigated to clarify the amino acid residues of HSA involved in the cephalosporin binding sites. The binding of the cephalosporins decreased remarkably with the modification of the tyrosine residues. These results suggest that the binding site of cephalosporins is located in the vicinity of warfarin binding site rather than benzodiazepine binding site and that tyrosine residues are involved in the cephalosporin binding site.


Orally active 2-(alkyloxycarbonyl)-2-alkylideneethyl esters of cephalosporins. 2-(Alkyloxycarbonyl)-2-alkylideneethyl esters of various aminothiazole-oxyimino cephalosporins have been synthesized and studied. They are useful alternatives to the currently existing orally active esters. Among the new esters synthesized, the 3'-azidomethyl cephem ester Ro 41-3399 (7k) presented an oral bioavailability superior to the corresponding pivaloyloxymethyl ester (9) in a rat model and was selected as a candidate for further evaluation.


Growing up heartsick: the experiences of young women with congenital heart disease. Young women with congenital heart disease (CHD) now survive to confront issues of sexuality, contraception, and pregnancy. Researchers have examined reproductive abilities and infant outcomes in these women, but have not addressed quality-of-life issues. Grounded-theory techniques were used to interview 13 women about the experience of growing up with CHD. The core variable identified was "growing up heartsick." This variable included manifestations of growing up with heart disease, such as feeling different from others, parental overprotectiveness, and fears of death. Two other related variables were also found: "growing up female" and "living against the body." "Growing up female" was characterized by concerns about fertility, contraception, and pregnancy in relation to CHD. Many of the participants were uninformed about their heart disease and reproductive matters. "Living against the body" was expressed in the women's feelings about their body size and their surgical scars. There were overlapping aspects of the categories; for example, manifestations of "growing up heartsick" appeared in each of the other categories.


The breast-feeding experience of women with type I diabetes. The purpose of this exploratory study was to identify the factors influencing the initiation and maintenance of breast-feeding in women with insulin-dependent diabetes. The lack of research in this area and the need for in-depth data necessitated exploratory methodology. Twenty-two mothers who were insulin dependent before pregnancy and who had given birth in the past 2 years were interviewed. Diabetes was not a principal factor in the decision to breast-feed or bottle-feed for the majority of the women. When diabetes was a factor, women were seeking a "normal" childbearing experience, including breast-feeding. Although the women did not perceive diabetes as influencing their breast-feeding experiences, they did find that maintaining good diabetic control required greater effort and flexibility during breast-feeding.


Sociocultural factors in depression in Asian Indian women. Depression is a pervasive illness with a wide distribution and is reported to be statistically more prevalent among women. The present study was undertaken to seek an understanding of depression in a sample of Asian Indian women. The research questions were (a) What sociocultural factors do adult depressed Indian women report as influences in the depression, and (b) how do these reported factors influence their treatment-seeking behavior? The setting was Madurai, India. The purposive, convenience sample comprised 30 Tamil-speaking married or widowed Hindu women ranging in age from 26 to 65 who had been diagnosed with depression. Tape-recorded interviews were conducted. Content analysis was completed on the data. Results indicate that cultural dictation of female role and lack of continued financial and emotional support, predominantly from spouses and other family members, were influential factors in depression. These along with religion and philosophy often influenced the decision to seek health care.


Attitudes of low-income clinic patients toward menopause. The bulk of menopause research has been conducted on samples of middle-class White women. In this study, attitudes toward menopause in a sample of 66 low-income women at a women's clinic were studied using Bowles's (1986) Menopause Attitude Scale (MAS) and the attitude segment of Millette's (1981) survey of attitudes and knowledge about menopause. The typical participant was a single, 34-year-old Black woman with a yearly income below $10,000. Research questions examined general attitudes toward menopause, and MAS scores of Bowles's middle-income, White sample were compared with those of the present low-income, predominantly Black sample. Results indicated a somewhat positive attitude toward menopause in the low-income sample. Although the trend was toward higher scores in the low-income group, only the 18- to 25-year-olds in the low-income group had significantly higher MAS scores than the corresponding age group in Bowles's sample. Nursing implications pertain to teaching and support group leadership.


Consequences of hysterectomy in the lives of women. A longitudinal study of 63 adult, premenopausal women of low socioeconomic status who underwent hysterectomies is reported. Face-to-face in-depth interviews with the women were conducted on the day before hysterectomy and 4 weeks and 3 months after hysterectomy. After the interview, each woman completed the Derogatis Sexual Functioning Inventory (Derogatis & Melisaratos, 1979). The Responses to Hysterectomy tool was mailed to the women about 2 years after hysterectomy. Before their hysterectomies, most of the women had both positive and negative feelings about the hysterectomy. By 3 months posthysterectomy, most women had fairly positive general and sexual outcomes. However, by 2 years posthysterectomy, there were less positive outcomes. Most women reported at least sometimes having negative symptoms that they associated with their hysterectomy. More research must be conducted to fully understand the experience of hysterectomy in women's lives.


Maternal reactions to fetal sex.

Maternal reactions to fetal sex. A descriptive design was used to characterize maternal reactions to the knowledge of fetal sex based on sex preference. The sample was 88 females with singleton pregnancies who had had an amniocentesis for fetal chromosome studies and met the following sample criteria: (a) Fetal karyotype and other studies were normal, (b) knowledge of fetal sex was desired, and (c) sex preference had been established. Maternal reactions to the knowledge of fetal sex were ascertained through a questionnaire I developed and that participants answered in writing. Sample characteristics were summarized using descriptive statistics, and the mothers' narrative responses were subjected to content analysis. Maternal sex preferences were equally split between male and female. However, there were differences in the way mothers who attained and mothers who did not attain their preferred fetal sex spoke of their fetuses.


Prediction of fertility from calfhood traits of Angus and Simmental heifers. The objectives of this study were to quantify the relationships between traits observed before the first breeding season and fertility of 946 Angus and 351 Simmental heifers and to use those traits to develop prediction equations for heifer fertility. Logistic regression methodology was used. Traits investigated were Julian birth date, age of the heifer's dam, birth weight, actual weaning and yearling weights, weaning and yearling weight ratios, 205-d weight, 365-d weight, and birth-weaning, weaning-yearling, and birth-yearling ADG and relative growth rate (RGR). In both breeds heifers that were younger at the start of the breeding season were less likely to conceive, but this effect was more important for Angus (logistic regression coefficient, b = -.032; P less than .01) than for Simmentals (b = -.015; P = .06). Weaning weight ratio was positively associated with heifer fertility (b = .025; P = .01 and b = .028, P = .04, respectively, for Angus and Simmental), whereas actual weaning weight was related curvilinearly to fertility of Angus heifers. The likelihood of conception was highest for Angus heifers weighing greater than or equal to 240 kg at weaning. The only postweaning trait associated with heifer fertility was weaning-yearling RGR. The likelihood of conception was highest for Angus heifers growing between .15 and .30% per day (P = .01), whereas fertility increased continuously (P = .04) for Simmental heifers as weaning-yearling RGR decreased. The maximum variations in fertility explained by models including all possible explanatory variables were 11.5 and 9.2% for Angus and Simmental, respectively. Results suggested that growth-related traits were relatively more important as a predictor of fertility for Simmental heifers and that age at the start of the breeding season was more important for Angus heifers. The combination of Julian birth date and weaning-yearling RGR produced the best models to predict heifer fertility for both breeds.


Reproductive response of yearling beef heifers to a melengestrol acetate-prostaglandin F2 alpha estrus synchronization system. A study was designed to evaluate estrus response and fertility after treatment with melengestrol acetate (MGA) and prostaglandin F2 alpha (PGF2 alpha) in yearling beef heifers. Three hundred four heifers at three locations were allotted to one of two treatments: Treatment 1 served as a nonsynchronized control (CON); and heifers in Treatment 2 received .5 mg of MGA.animal-1.d-1 for 14 d and 25 mg of prostaglandin F2 alpha (PGF2 alpha) 17 d after MGA (MGA-PGF). Heifers in CON and MGA-PGF groups were artificially inseminated 12 h after observed estrus for 21 and 6 d after PGF2 alpha, respectively. Blood samples were collected from each heifer 10 d before and on the day MGA feeding began and 10 d before and on the day PGF2 alpha was administered. Heifers with concentrations of serum progesterone greater than 1 ng/mL on either date before administration of MGA or PGF2 alpha were considered pubertal. More (P = .02) prepubertal heifers that received MGA attained puberty by initiation of breeding than did CON heifers (72 vs 45%, respectively). The proportion of heifers that displayed estrus within 6 d after PGF2 alpha was greater (P less than .001) for MGA-PGF than for CON heifers (77 vs 25%, respectively) but was also influenced by location (P = .03). Conception rate at first service for MGA-PGF heifers that attained puberty during MGA feeding and before PGF2 alpha was not different (P = .50) from that of CON that attained puberty during the same period.(ABSTRACT TRUNCATED AT 250 WORDS)


Accelerated lambing using exogenous progesterone and the ram effect. An experiment was conducted to determine whether controlled internal drug release devices-type G (CIDR-G) could be used in conjunction with the ram effect to advance the breeding season and lambing and thereafter could be reapplied to stimulate breeding of ewes to produce a second lambing in late summer. Finn crossbred and Columbia ewes were treated with CIDR-G from July 6 to 18. Rams, which had been isolated from ewes, were joined with the flock upon CIDR-G removal. All 59 CIDR-G-treated ewes exhibited estrus, and 55 lambed from breeding within a 30-d period after CIDR-G withdrawal. Eighteen of 19 contemporary control ewes (no CIDR-G) were bred, and 16 lambed. Ewes that had lambed from the CIDR-G and control groups were retreated as before, with CIDR_G inserted March 1 and withdrawn March 13, concomitant with sudden exposure to rams. Of 55 CIDR-G-treated sheep, 53 were bred and 45 lambed. All 16 control ewes were bred and lambed. A second experiment was conducted to determine whether treatment with CIDR-G and the ram effect was effective in mid-spring. The CIDR-G were applied for 12 d and removed on May 1 or 6 from Finn crossbred, Columbia, and Polypay ewes. Rams were introduced upon CIDR-G withdrawal. Of 59 CIDR-G-treated ewes, 58 exhibited estrus and 45 lambed. Twenty-three of 30 contemporary control ewes were bred, and 20 lambed.(ABSTRACT TRUNCATED AT 250 WORDS)


Sex role typology as a function of age among registered nurses. The present study was designed to investigate the relationship between sex role orientation and age in women working in a traditional occupation. It was hypothesized that older working female nurses would be more androgynous in sex role orientation than their younger counterparts. Ninety-eight female registered nurses ranging in age from 30 to 59 completed the Personal Attributes Questionnaire and sociodemographic data. Contrary to prediction, age had no significant effect on sex role orientation. It was concluded that (a) no change in masculinity/femininity self-descriptions occur over time, (b) only some women change, and (c) changes may proceed in different directions in response to shifts in role responsibilities or other situational events.


Content analysis: method, applications, and issues. Content analysis research methodology is detailed, its procedures are described, some examples of its application are provided, and the controversial issues surrounding its use are discussed. Unlike strictly qualitative designs, content analysis has external validity as a goal. Because of its focus on human communication, content analysis offers practical applicability, promise, and relevance for research involving the practice and education of nurses and other helping professionals.


Lactation performance of sows injected with growth hormone-releasing factor during gestation and(or) lactation. Fifty-two Yorkshire x Landrace gilts were equally allotted to four treatments: 1) controls, saline injections (CTL); 2) injections of 12 mg of growth hormone-releasing factor (GRF) (1-29)NH2 thrice daily (0700, 1500, and 2300) from d 100 of gestation until parturition (GEST); 3) injections of GRF thrice daily from d 3 to 29 of lactation (LACT); and 4) injections of GRF thrice daily during gestation (d 100 to parturition) and lactation (d 3 to 29) (GEST-LACT). Within 48 h of birth, litters were standardized to 9 +/- 1 pigs. Weights of the pigs were recorded weekly from birth (less than 24 h) until weaning (d 30) and on d 42 and 56. Weights of gilts at mating, d 110 of gestation, 1 d postfarrowing, and at weaning also were recorded. On d 24 of lactation, milk yield was estimated by the weigh-suckle-weigh method, and a representative milk sample was obtained the next day. Jugular vein cannulas were inserted into six sows per treatment on d 26, and a 6-h blood profile (sampling every 20 min from 0600 to 1200) was obtained on d 29. Daily feed consumption of sows was recorded throughout the study. Weights of the pigs at any one time or survival until weaning were not affected by treatments (P greater than .1). Sows injected with GRF during GEST (P = .05) and(or) LACT (P less than .01) were lighter than CTL sows at weaning; in addition, sows treated during lactation had less backfat (P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)


Management systems for Holstein steers that utilize alfalfa silage and improve carcass value. Two trials were conducted to evaluate the effect of two-phase feeding systems using alfalfa silage or pasture on the performance and carcass characteristics of Holstein steers. During the growing phase (98 d) of Trial 1, steers received alfalfa silage at either 40, 22, or 7% of the DMI. During the growing phase of Trial 2, steers received alfalfa silage at either 39 or 8% of their DMI (140 d) or grazed an orchardgrass/ryegrass pasture (175 d). During the finishing phase, all steers received a 90% concentrate diet until they reached a small degree of marbling at the 12th rib as predicted by ultrasonic attenuation. In Trial 1, one-half were initially implanted with zeranol and reimplanted with trenbolone acetate and estradiol (TBA+E) after 98 d. In Trial 2, one-half were implanted twice with TBA+E at a 120-d interval. Trial 1 average daily gains (kilograms) for the 40, 22, and 7% alfalfa silage treatments were 1.14, 1.25, and 1.38 in Period 1 (all different from each other at P less than .05); 1.31, 1.34, and 1.19 in Period 2; and 1.25, 1.25, and 1.26 overall. Trial 2 average daily gains (kilograms) for the 39, 8, and pasture treatments were 1.50, 1.71, and .92 for Period 1 (all different from each other at P less than .05); .93, .75, 1.11 for Period 2 (all different from each other at P less than .05); and 1.16, 1.17, and 1.03 overall (pasture different at P less than .05). No consistent effects of diet or implant on carcass characteristics were observed.(ABSTRACT TRUNCATED AT 250 WORDS)


Predicting the profitability of alfalfa silage and pasture feeding systems for Holstein steers. Data from two research trials were used as inputs to a model to project the return to capital of two-phase alfalfa silage and pasture feeding systems for Holstein steers. This approach presents a methodology for applying research data over widely varying conditions. Cattle received a 40% (High = H), 22% (Medium = M), or 8% (Low = L) alfalfa silage diet or grazed an orchardgrass/ryegrass pasture (Pasture = P) during Period 1. During Period 2, cattle consumed a 90% concentrate diet until ultrasonic attenuation predicted that the longissimus muscle contained a small degree of marbling. All systems produced similar carcass grades, so profitability differences resulted from relationships between feed requirements, cost of feed, and cost of time. Cattle grazed on pasture yielded a higher return to capital during Period 1 and over the entire feeding system. Among the other systems, L returned more to capital during Period 1, but over the entire feeding system additional silage returned more when silage cost was less than $32 per 1.02 t (as fed). Above this cost, the continuous 90% concentrate diet yielded a higher return. Cattle implanted with trenbolone acetate and estradiol returned $60 in Trial 1 and $86 in Trial 2 more per animal than did unimplanted steers.


Forage availability x heifer phenotype interactions for Brahman-Hereford F1 yearling heifers grazing humid pasture and semiarid rangeland. Yearling heifer growth data were obtained during 4 yr for 524 heifers allotted to either humid bermuda grass pastures (Overton) or semiarid rangeland (Uvalde). Each year, heifers were allotted on April 15 to four forage availability levels (400 to 2,800 kg of DM per 100 kg of BW at Uvalde and 80 to 260 kg of DM per 100 kg of BW at Overton) maintained by varying the stocking rate monthly until mid-October of each year. Forage availability and yearling heifer characteristics (weight, condition score, and height at hooks, taken on April 15) were treated as continuous variables in regression analyses. Final heifer weight, height, and condition responses to increased forage allowance were related to yearling phenotypes differently for the two locations. Generally, at Overton, forage availability influenced final characteristics to a greater extent than did yearling variables, whereas the trend was the opposite at Uvalde. At Uvalde, the yearling characteristic that had the largest effect on performance was height at hooks. Yearlings with large frames benefited from increased forage allowance by accumulating body fat at a faster rate than those with small frames. In contrast, at Overton, the yearling characteristic that had the largest effect on performance was condition. Fat heifers responded to increased forage availability to gain even greater advantages in fatness at the expense of potential growth in height and, thus, achieved early maturation. Yearling phenotypes were more broadly adapted to arrays of forage availability for humid, improved pastures than for semiarid rangeland.


Effects of growth curve parameters on cow efficiency. Weight-age data from 50 Retinta beef cows from 8 to 97 mo of age located in southwestern Spain were fitted to von Bertalanffy, Brody, and Richards functions to determine the relationship between growth curve parameters and cow efficiency. Only cows having at least 31 weights were included in the analysis. Von Bertalanffy, Brody, and Richards functions were fitted to weights of each cow. Relevant parameters of the three functions are A and K, associated with the asymptotic mature weight and rate of maturing, respectively. Criteria for comparisons among the three functions were computing difficulty, goodness of fit, and lack of bias of A. Productivity indicators were number of calves weaned during the first five calving seasons (NC), average birth weight (BWT), average weaning weight (WW), and average weaning weight per cow per year (WWY). The von Bertalanffy function was selected as the most appropriate. Least squares means for A and K were 650 +/- 8.17 kg and .038 +/- .001 mo-1, respectively. The values of NC, BWT, WW, and WWY were 4.0 +/- .11 calves, 38.2 +/- .4 kg, 218 +/- 5 kg, and 172 +/- 5 kg, respectively. Regression analysis for A indicated a decrease in NC when mature weight increased (P less than .05). There was a nonsignificant trend for heavier cows (higher A) to have calves with heavier BWT or WW. The value of WWY increased (P less than .05) with increased maturing rate (K) of cows. No significant associations were found between K and BWT or WW.(ABSTRACT TRUNCATED AT 250 WORDS)


Classical and mixed-model analysis of an index selection experiment for fecundity in Drosophila melanogaster. A comparison of three family indices to increase number of pupas from 3-d lay in Drosophila melanogaster is reported. The three indices were Id, based exclusively on dam's information; Ihd, based additionally on dam's full-sibs' and half-sibs' information; and Ihs, which also included the sire's full-sibs' and half-sibs' records. Three lines, D, HD, and HS, were selected, each according to one of the three indices: Id, Ihd, or Ihs. Each line consisted of 10 sires and 60 dams. Each dam contributed one male offspring and three female offspring. Seven generations of selection were performed in a two-replicate experiment. The expected advance of Ihs and Ihd over Id in the seventh generation was .38 and .15 phenotypic standard deviations, respectively. The experiment was analyzed in terms of both classical ordinary least squares (OLS) and mixed-model methodology (MMM). The phenotypic trends in the first replicate were 4.06 +/- 1.74, 1.42 +/- 1.76, and .26 +/- 1.94 pupas per generation for Lines D, HD, and HS, respectively, and in the second replicate 8.52 +/- 2.40, 6.16 +/- 3.21, and 4.21 +/- 2.60, respectively. The genetic trends in the first replicate were 2.18 +/- .61, 1.08 +/- .67, and .24 +/- .68 pupas per generation and, in the second replicate, 2.51 +/- .60, .16 +/- .61, and .05 +/- .64 for Lines D, HD, and HS, respectively. Despite theoretical expectations, the Id index was consistently better than the more complex indices. Several explanations for these results are possible: 1) smaller than expected selection differential, 2) inbreeding depression, and 3) incorrect heritability used to construct the indices.(ABSTRACT TRUNCATED AT 250 WORDS)


Performance of crosses among Hereford, Angus, and Simmental cattle with different levels of Simmental breeding: VI. Maternal heterosis of 3- to 8-year-old dams and the dominance model. Data from Hereford, 25% Simmental-75% Hereford, 50% Simmental-50% Hereford, and 75% Simmental-25% Hereford dams were used to estimate maternal heterosis and level of agreement with the dominance model. Cows were located at the Northern Agricultural Research Center near Havre, MT and were managed consistent with practices for western range environments. Sample halves of dam breed groups were bred to Charolais and Tarentaise sires to produce calves at 3 to 8 yr of age. There were 766 exposures to breeding that resulted in 581 calves. Breed group means for most traits supported the dominance model. Maternal heterosis was estimated by regression techniques for 22 cow and calf traits. Maternal heterosis was not significant for day of conception, number of services, gestation length, or calving difficulty. Estimates of maternal heterosis for calf growth traits ranged from .7% for weaning height to 5.2% for weaning weight and 7.5% for weaning condition score. Calf weight per unit of cow weight at weaning showed significant maternal heterosis (7.1%). Higher levels of maternal heterosis were exhibited for milk production (8.2 to 11.1%) and the negative, but nonsignificant, estimate of maternal heterosis for early minus late milk production suggested more persistent lactation for crossbred cows. Maternal heterosis was 11.5% for proportion of dams that calved and 10.4% for proportion of dams that weaned calves. Calf weaning weight per cow exposed to breeding, a characteristic combining calf growth and dam reproduction, exhibited 17.9% maternal heterosis.


Additive and nonadditive differences in postweaning growth and carcass characteristics of Devon, Hereford, and reciprocal-cross steers. Postweaning growth and carcass characters of 110 steers from a complete two-breed diallel of the Devon and Hereford breeds were examined under two environments. Additive and nonadditive effects were estimated using linear contrasts for several growth and carcass traits. Steers from each of the four breed groups were grown postweaning to slaughter in high- and low-nutrition environments. Weights were recorded every 2 mo. At slaughter, hot carcass weight, longissimus muscle area, kidney and channel fat, and subcutaneous fat at nine sites were measured. Heterosis for postweaning growth rate was 3.9% (P less than .01) and for slaughter weight 5.0% (P less than .01). Within the low-nutrition environment during periods of slow and fast growth, the Devons and Herefords performed differently. The growth rate of the steers differed in the two environments; however, heterosis for slaughter weight was of the same magnitude in both environments. No differences existed between the straightbreds or between the reciprocal crosses for slaughter weight. Crossbred carcasses were 7.4% heavier (P less than .01) than the straightbred carcasses; however, this effect was removed after adjustment for differences in slaughter weight. Heterosis for longissimus muscle area and carcass fatness were not significant after adjusting for carcass weight. Additive differences occurred for carcass traits. Devon carcasses had more kidney and channel fat (P less than .05) at a constant hot carcass weight and differences occurred in the partitioning of fat within the subcutaneous depot. No significant maternal effects were observed for the carcass traits measured. Crossbreeding increased carcass weight without altering composition, and relative performance was not affected by the diverse environments.


Detection of linkage between genetic markers and genes that affect growth and carcass traits in pigs. Segregation of paternal marker alleles in the progeny of a single boar was used to estimate linkage between the marker genes and associations of these genes with quantitative trait loci (QTL). The sire was heterozygous at four polymorphic marker loci, haptoglobin (HP), glucosephosphate isomerase (GPI), phosphogluconate dehydrogenase (PGD), and esterase D (ESD), and sired 30 litters during an 8-mo period. Glucosephosphate isomerase and PGD were linked (theta = .09; P less than .005). The phase of these two loci in the sire was determined to be GPI A-PGD B, GPI B - PGD A. NO other linkages were detected. Growth (135 less than or equal to n less than or equal to 172) and carcass data (70 less than or equal to n less than or equal to 80) were analyzed assuming a fixed linear model. Least squares means were compared for differences in growth and carcass traits between pigs that inherited alternative paternal marker alleles. Pigs that inherited the GPI A allele from the sire had a 22-g higher daily live weight gain postweaning and reached 103 kg live weight in 2.6 fewer days than did pigs that inherited the GPI B allele (P less than .05), indicative of the presence of gene(s) that affect rate of gain linked to the GPI locus. Pigs that inherited the PGD B allele had a .14 unit higher score for muscle firmness (score ranged from 1 to 3 units) than pigs that inherited the PGD A allele (P less than .05). Pigs that inherited the HP 3 allele had a .06-kg higher weaning weight and a .11 lower ham muscle mass score than did pigs that inherited the HP 2 allele from the sire (P less than .05). No associations with quantitative traits were detected for ESD.


Correlated responses in reproductive and carcass traits to selection for 200-day weight in Duroc swine. Correlated responses in reproductive and carcass traits from a line of Duroc pigs selected for increased 200-d weight along with a randomly selected control line were studied in 189 litters (116 select, 73 control) and 191 pigs (106 select, 85 control), respectively. Reproductive and maternal traits studied included litter sizes born, born alive, and alive at 21 d and litter weight at birth and at 21 d. Carcass traits studied were carcass length, longissimus muscle area, average backfat thickness, 10th rib backfat thickness, specific gravity, weights of closely trimmed ham, loin, and shoulder, belly weight, subjective scoring of the longissimus muscle for color and marbling, estimated percentage of muscle and lean gain per day. Total weighted cumulative selection differential for 200-d weight was 81.7 kg. The realized heritability for 200-d weight was .18 +/- .08, and the change in 200-d weight was 2.5 +/- 1.2 kg per generation. The regression coefficient of litter size born on generation was -.29 +/- .12 (P less than .10) pigs per generation. None of the other regression coefficients for the reproductive traits differed from zero. Average backfat thickness, 10th rib backfat thickness, and belly weight increased by .093 +/- .016 cm, .122 +/- .029 cm, and .089 +/- .040 kg, respectively, per generation. Specific gravity, ham weight, shoulder weight, color score, and percentage of muscle decreased -.00086 +/- .00024, -.165 +/- .013 kg, -.104 +/- .011 kg, -.035 +/- .015 points, and -.47 +/- .12%, respectively, per generation in response to the selection.(ABSTRACT TRUNCATED AT 250 WORDS)


Sexual performance of rams in serving capacity tests predicts success in pen breeding. The purpose of this study was to determine the extent to which sexual performance (serving capacity) tests can be used to predict the sexual behavior and reproductive success of rams in the context of pen mating. Standard serving capacity tests were used to select four low (LP) and four high-performing (HP) rams from a population of 94 yearling males. Each selected ram was then exposed to approximately 30 estrus-synchronized ewes for a 9-d period. Ejaculations observed and mounting marks left on ewes confirmed the greater (P less than .001) sexual activity of the HP rams in the field. In addition, ewes exposed to HP rams had a higher lambing percentage, more lambs born, and more live lambs born per ewe. Ram classification was not related (P greater than .60) to the number of lambs born per ewe lambing (prolificacy). It was concluded that serving capacity tests, properly conducted, can be used to predict ram mating performance and thus aid in establishing more efficient ram-to-ewe stocking rates.


Relative importance of vision and olfaction for detection of estrus by bulls. The objective of this experiment was to determine the relative importance of olfaction and visual observation of heifer mounting behavior to the detection of estrus by bulls. An observation pen was designed to allow the evaluation of the preference of five sexually experienced bulls under three sets of stimuli. The observation pen was 4 m x 17 m with a smaller enclosure (2 m x 4 m) at each end that housed either a pair of heifers in diestrus (D), a pair of heifers in estrus that were allowed to mount one another (EM), or a pair of heifers in estrus that were separated by an aluminum panel to prevent mounting behavior (E). The preference of bulls was determined between EM heifers compared to D heifers, EM heifers compared to E heifers, and E heifers compared to D heifers. Each bull was individually allowed 5 min inside the observation pen to demonstrate its preference. Preference was defined as the total time that bulls spent within 2.5 m of either pair of heifers. Each bull was subjected to 10 observation periods of each set of stimuli during a 4-mo period. Bulls preferred to be near EM heifers compared with either E or D heifers (P less than .05). However, the bulls demonstrated no preference (P greater than .05) for E heifers compared with D heifers. These data indicate that when physical contact is denied, bulls use visual observation of female homosexual behavior as the primary indicator of estrus and that olfaction alone provides insufficient stimuli for bulls to indicate preference toward heifers in estrus compared with heifers in diestrus.


Effect of a hot environment on performance, carcass characteristics, and blood hormones and metabolites of pigs treated with porcine somatotropin. A study was conducted to compare the effects of a single 100-mg recombinant porcine somatotropin (rpST) implant on performance, carcass characteristics, and blood hormones and metabolites of 40 finishing pigs exposed to either a thermoneutral (TN; 18 to 21 degrees C) or hot environment (H; 27 to 35 degrees C) for 28 or 35 d. Pigs in H gained at a slower rate (P less than .01) than pigs in TN. Control and rpST-treated pigs gained at similar rates in respective environments. The rpST-treated pigs consumed 13% less feed (P less than .01) than the control pigs in both environments, and pigs in H consumed 19% less feed (P less than .01) than pigs in TN. Feed efficiency for rpST-treated pigs was 15% better (P less than .01) than that for control pigs; environment had no effect on feed efficiency. When slaughtered, pigs treated with rpST had less (P less than .01) leaf fat and less (P less than .01) 10th rib backfat than control pigs. Pigs in H had a lower (P less than .01) final BW and less leaf fat and backfat than pigs in TN. The rpST and H had various effects on blood hormones and metabolites. The results demonstrated that the benefits of this form of rpST treatment achieved under TN were also achieved in H with no interactions between the hormone and environment.


Assessment of factors regulating serum growth hormone binding protein in pigs. These studies were conducted to examine the influence of several variables on the growth hormone binding protein (GHBP) activity in serum of pigs. Continuous long-term porcine somatotropin (pST) injections (daily for 6 to 7 wk) increased GHBP activity (P less than .05). However, periodic short-term pST injections (daily, every 2nd d, or every 4th d for 2 wk) did not cause a significant change in GHBP levels (P greater than .40). Although fasting seems to reduce liver GH receptors, no difference was observed between fed animals and animals fasted for 5 d (P greater than .30). Between 0 and 6 mo of age, boar and gilt serum GHBP activity were not significantly different from each other but increased with age in both sexes (P less than .0001). There was no significant correlation between serum GHBP and BW at 6 mo of age in this study (P greater than .30). In pregnant sows, GHBP concentrations were highest at the beginning (d 72) of the third trimester (P less than .05). Growth hormone receptor activity reported by other researchers and GHBP activity in this study seem to vary similarly except during fasting, which may indicate alternate regulation of either the GHBP or the GH receptor.


Influence of dietary palm oil supplementation on serum lipid metabolites, carcass characteristics, and lipid composition of carcass tissues of growing ram and ewe lambs. The objective of this research was to determine the influence of dietary palm oil supplementation on carcass characteristics and lipid composition of tissues from growing lambs. Twenty-eight Suffolk x Hampshire lambs were weaned at 60 d of age (average 36 kg BW) and assigned to a 2 x 2 factorial arrangement consisting of diet (control [NPO] or 10.6% added dietary palm oil [PO]) and sex (ram vs ewe). The NPO diet (77% forage and 23% concentrate) contained 11.2% CP and 2.66 Mcal of ME/kg. Palm oil replaced molasses in the PO diet. Lambs were individually given ad libitum access to feed for 60 d to a final BW average of 50.1 kg. Lipid composition of the longissimus muscle and corresponding subcutaneous (s.c.) adipose tissue was determined by gas-liquid chromatography (GLC). Lambs fed PO were fatter (P less than .01) than lambs fed NPO (.77 vs .56 cm, s.c. fat). Diet had no effect on cholesterol content of lean tissue; however, feeding PO increased the saturated fatty acids of lean tissue. The s.c. fat from lambs fed PO had less (P less than .01) cholesterol (64.79 vs 89.67 mg/100 g) and more saturated fatty acids than that from lambs fed NPO. Ewes were fatter (P less than .01) than rams, yet they had less cholesterol content in the s.c. adipose tissue (68.71 vs 85.74 mg/100 g). High amounts of dietary palm oil fed to growing lambs caused changes in fatty acid deposition and cholesterol metabolism and may be a useful investigative tool to study lipid metabolism in growing ruminants.(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of implanting ram and wether lambs with zeranol at birth and weaning on palatability and muscle collagen characteristics. Thirty-five zeranol-implanted (I) and nonimplanted (NI) ram and wether lambs representing four treatments (implanted rams [IR], nonimplanted rams [NIR], implanted wethers [IW], and nonimplanted wethers [NIW]) were evaluated for meat palatability and muscle collagen characteristics. Rib (longissimus muscle, LM) chops from I lambs were juicier (P less than .05) than rib chops from NI lambs. Chops from IR lambs had more (P less than .05) detectable connective tissue and lower myofibrillar and overall tenderness scores than chops from NIR, IW, or NIW lambs. Warner-Bratzler shear (WBS) values tended to be higher (P = .06) for LM chops from rams than for those from wethers, but WBS values for Biceps femoris (BF) chops were similar (P greater than .05) for rams and wethers. Implanting did not affect (P greater than .05) WBS values. Rams had more (P less than .05) LM heat-labile (soluble, SC), nonheat-labile (insoluble, IC), and total collagen (TC) and a higher (P less than .05) percentage of SC (SC/TC) than did wethers. Soluble collagen, TC, and percentage of SC for the BF were higher (P less than .05) and IC tended (P = .09) to be higher in chops from rams than in those from wethers. Implanting did not affect (P greater than .05) collagen amount or solubility. Serum nonprotein hydroxyproline (NPHP) was higher (P less than .05) in rams than in wethers throughout the feeding period and tended (P = .05) to be higher at slaughter. Implanting did not affect (P greater than .05) serum NPHP.(ABSTRACT TRUNCATED AT 250 WORDS)


Ultrasonic prediction of carcass merit in beef cattle: evaluation of technician effects on ultrasonic estimates of carcass fat thickness and longissimus muscle area. The objective of this study was to determine technician effects of live animal ultrasonic estimates of fat thickness (FTU) and longissimus muscle area (LMAU). Steers (n = 36) representing four breed-types (Brown Swiss, Average Zebu-cross Mexican, Corriente Mexican, and typical British crossbred) of commercial slaughter cattle were isonified to estimate accuracy and repeatability of fat thickness (FT) and longissimus muscle area (LMA) measurements by two experienced technicians. Repeated measures of FTU and LMAU were taken by technicians on two consecutive days with an Aloka 500V ultrasound unit equipped with a 3.5-MHz, 172-mm scanning width, linear-array transducer. Ultrasonic estimates of fat thickness and LMAU were taken at the 12th and 13th rib interface 48 h before slaughter; carcass fat thickness (FTC) and longissimus muscle area (LMAC) were measured 48 h postmortem. Means for FTU, FTC, LMAU, and LMAC were .91 +/- .36 cm, .82 +/- .40 cm, 70.7 +/- 9.43 cm2, and 72.4 +/- 8.9 cm2, respectively. Ultrasound and carcass measures of FT and LMA were different (P less than .01) among breed-types but were not different (P greater than .10) between technicians or for technician x breed-type interactions. Pooled simple correlation coefficients (P less than .01) were .87 and .86 between FTU and FTC and .76 and .82 between LMAU and LMAC for Technicians 1 and 2, respectively. Repeatabilities estimated by intraclass correlation methods were .91 +/- .03 and .81 +/- .06 for images repeated over 2 d and .95 +/- .02 and .83 +/- .05 for images repeated by two technicians for FT and LMA, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Relationship between blood hemoglobin, plasma and tissue iron, muscle heme pigment, and carcass color of veal. In 41 veal calves divided into three groups and fed different levels of dietary iron, blood hemoglobin, plasma iron, liver, spleen, and muscle iron, muscle heme pigment, and carcass muscle color at slaughter were studied. At 45 min postmortem, total carcass color was visually evaluated in the 41 carcasses. In different muscles of the carcasses the color was measured instrumentally using an invasive color measurement method at 45 min postmortem (MCDI score) and a surface color measurement method at 20 h postmortem (Minolta L*, a*, b*, and Chroma scores). Among the three groups, differences (P less than .05) in muscle iron concentrations, muscle heme pigment concentrations, and Minolta a*, b*, and Chroma scores were found. Most striking were the differences in mean iron concentrations in the longissimus thoracis muscles between Groups A (29 micrograms/g DM) and B (44 micrograms/g DM) and in the semimembranosus muscles between Groups A (31 micrograms/g DM) and C (45 micrograms/g DM). The correlations found between Minolta L*, a*, or Chroma score and the iron and heme pigment concentrations in the semimembranosus muscles were high in comparison with those found in the longissimus thoracis and rectus abdominis muscles. Compared with the plasma iron concentration, the blood hemoglobin concentration showed higher correlations with muscle iron and muscle heme pigment concentrations. It can be concluded that different iron concentrations in the milk replacer during the first 7 wk of fattening influence, to some extent, muscle iron and muscle heme pigment at slaughter. However, these differences were not measurable in the overall visual color evaluation of the carcass surface muscles.


The effect of postexsanguination infusion of beef on composition, tenderness, and functional properties. Ninety culled dairy cows were used in this study and were paired by weight and conformation similarity. Forty-five cows were arterially infused immediately after bleeding with 10% volume by weight of a solution composed of dextrose (.23%), glycerin (.21%), a phosphate blend (.14%) and maltose (.1%). The remaining cows (45) served as controls. In infused carcasses, some quantity of solution retained was in the following order: supraspinatus, chuck greater than longissimus, loin greater than semitendinosus, round muscles. Accordingly, percentage of protein, ether-extractable fat, and protein fat-free amounts were lowered (P less than .05) and percentage of moisture and moisture protein ratio were raised (P less than .05) in the supraspinatus muscle. Tenderness (P less than .01) and protein extractability (P less than .15) were improved. No difference was observed in water-holding capacity between infused and control carcasses. Percentages of moisture fat-free (r = .85) and protein fat-free (r = -.97) were highly correlated to moisture-protein ratio. Moisture percentage of the fat-free tissue was shown to be a more consistent indicator of added moisture in infused whole carcasses compared with moisture:protein ratio and percentage of protein fat-free. Very low correlations were observed between tenderness, percentage of moisture, percentage of water-holding capacity, and ether-extractable fat. The economics of the infusion process to the beef industry is discussed.


The effect of alkaloids and seed extracts of endophyte-infected tall fescue on prolactin secretion in an in vitro rat pituitary perfusion system. The objective of this research was to measure the effects of endophyte-infected tall fescue seed extract and various alkaloids associated with the endophyte on in vitro prolactin secretion by rat hemipituitaries. Rat anterior pituitaries (AP) were dissected into halves and placed in temperature-controlled culture chambers (37 degrees C). The tissue was perfused with culture media at a flow rate of 12 mL/h. After perfusion for at least 90 min with control media, AP halves were exposed to their respective treatments for 15 min before they were returned to the control media. The treatments for Exp. 1 were .01 micrograms of alpha-ergocryptine/mL of culture medium, .01 microgram of ergonovine/mL of culture medium, .01 gram-equivalents of endophyte-infected tall fescue seed/mL of culture medium, and .01 gram-equivalents of endophyte free tall fescue seed/mL of culture medium. Treatments for Exp. 2 consisted of 10(-4), 10(-6), and 10(-8) M concentrations of perloline, N-formyl loline, N-acetyl loline, N-methyl loline, and alpha-ergocryptine. alpha-Ergocryptine suppressed (P less than .10) prolactin secretion in both experiments. Ergonovine and perloline both stimulated (P less than .10) prolactin secretion. The loline alkaloids (N-formyl loline, N-acetyl loline, N-methyl loline) had no effect on prolactin secretion. The endophyte-infected seed extract treatment suppressed (P less than .10) prolactin secretion. The endophyte-free seed extract treatment had no effect on prolactin secretion. In Exp. 2, prolactin secretion from AP responded to alpha-ergocryptine treatment in a dose-dependent fashion.(ABSTRACT TRUNCATED AT 250 WORDS)


Release of luteinizing hormone after administration of naloxone in pre- and peripuberal heifers. This study was conducted to investigate regulation of LH release by opioid peptides during puberal development in beef heifers. Fourteen heifers were randomly assigned to receive naloxone (opioid antagonist) i.v. at dosages of either 1 mg.kg BW-1.wk-1 (Dose 1) or .25 mg.kg BW-1.wk-1 (Dose 2) for 13 wk or until puberty. Blood was sampled (one sample every 15 min) 6 h before (prenaloxone) and 2 h after naloxone administration. Two hours after naloxone administration, GnRH (10 ng/kg BW) was administered and blood was sampled for 1 h. Nine heifers attained puberty during the study. There were no differences between naloxone dosage groups for any measured variables. Therefore, heifers were grouped dependent on the attainment of puberty. Prenaloxone concentrations of serum LH and LH pulse frequency were normal for prepuberal heifers. Serum LH concentrations increased within 30 min after naloxone 135 of 139 times it was administered (P less than .05). Serum LH concentrations during the hour after naloxone were higher (P less than .05) than those during the hour before naloxone in both puberal and nonpuberal heifers. In puberal heifers, serum LH pulse height during the hour after naloxone was greater (P less than .02) at 5 wk before puberty and lower (P less than .02) the week before puberty than at other times during the trial. There was no effect of week on serum LH pulse height after naloxone in heifers that failed to attain puberty during the study. Response of LH to GnRH was similar between groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Ovarian follicular changes after weaning in sows. Three experiments investigated ovarian follicular development in sows whose litters were weaned at 28 to 31 d of lactation. Unilateral ovariectomy near the time of weaning was used to assess early follicular characteristics and to identify those sows that would not return to estrus within 10 d after weaning. This allowed segregation of and exclusion from the study those sows that had a prolonged interval from weaning to first estrus. In Exp. 1, 82 and 72% of the large follicles that were marked at 48 or 72 h after weaning (10 sows per time point) were subsequently identified as corpora lutea. In Exp. 2, sows (seven to nine per time point) were unilaterally ovariectomized at 0, 6, 12, 18, 24, or 48 h after weaning, and follicular fluid was evaluated for changes in steroid concentrations. Progesterone concentrations in fluid from medium-sized (4 to 6 mm) follicles increased by 6 h after weaning and then declined through 24 h concomitant with increases in testosterone and estradiol. For Exp. 3, follicular fluid and granulosa cells from individual follicles were obtained from sows (seven to nine per time point) at 0, 6, and 24 h after weaning. In follicular fluid, insulin-like growth factor I (IGF-I) concentrations were not correlated (P greater than .05) with concentrations of progesterone, testosterone, or estradiol, or with granulosa cell production of estradiol during culture in androstenedione-supplemented medium.(ABSTRACT TRUNCATED AT 250 WORDS)


Responses of calves to treadmill exercise during beta-adrenergic agonist administration. Calves perorally administered the beta-adrenergic agonist (beta-A) clenbuterol for 28 d were studied before, during, and after a 12-min treadmill exercise. During exercise on d 1 of clenbuterol administration, respiratory rate, respiratory minute volume, and heart rate and blood glucose, lactate, and insulin concentrations increased more in beta-A-treated calves than in controls. Oxygen extraction rate and growth hormone concentrations were lower in clenbuterol-treated calves, whereas oxygen consumption, carbon dioxide production, and blood cortisol concentration increased similarly in the absence and presence of the beta-A. After 2 wk of daily clenbuterol administration, respiratory rate and respiratory minute volume during exercise were still higher and oxygen extraction was still lower, whereas all other measures were similar to those in controls. The increased heart rate in response to isoproterenol after 3 wk of clenbuterol administration was reduced markedly in resting but only slightly in exercising animals, whereas heart rate reduction by propranolol during exercise was similar to that in controls. Seven days after withdrawal of clenbuterol, newly administered clenbuterol evoked the same effects as on d 1. In conclusion, there were marked reactions to the first clenbuterol treatment that were in part enhanced during treadmill exercise. After 2 wk of beta-A administration, animals responded much less to the beta-A and changes were not different from those in controls. Resensitization to the beta-A was observed 7 d after its withdrawal.


Effects of melatonin treatment on the attainment of puberty in heifers. This experiment determined the effect of treatment of 3- to 4-mo-old heifer calves with exogenous melatonin, in early summer, on the attainment of puberty the following spring. Hereford heifers, born between February 22, and March 16, were paired by age and BW and assigned at random within pair to receive an ear implant of melatonin (MEL, n = 12) or to serve as controls (C, n = 12). The implant period was 5 wk, starting June 10 at a mean age of 105 +/- 5 d and 134.4 +/- 3.5 kg BW. Puberty was evaluated the following year on four occasions: January 26, March 19, May 2, and June 1. One each date, rectal palpation of the ovaries was performed, blood samples were taken to assess concentrations of progesterone (P4), and BW was determined. Puberty was considered to have occurred when concentrations of P4 were greater than or equal to .5 ng/mL concomitant with a palpable corpus luteum (CL), or when concentrations of P4 were greater than or equal to 1 ng/mL and a CL was present on the next date. At implant removal, concentrations of melatonin in plasma collected at 1000 to 1400 were 69.5 +/- 6.3 and 16.7 +/- 2.4 pg/mL for MEL and C heifers, respectively. On that and subsequent occasions, neither BW nor ADG differed between MEL and C heifers. Treatment with melatonin increased the incidence of heifers pubertal by the second observation date (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)


Sulfate supplementation of Angora goats: metabolic and mohair responses. Eight castrated male Angora goats were used in a repeated, simultaneous 4 x 4 Latin square designed experiment to evaluate metabolic and mohair responses of Angora goats to sulfate supplementation. Goats had ad libitum access to isonitrogenous diets containing a .16 (basal), .23, .29, or .34% S (DM basis), which yielded N:S ratios of 12.7, 8.3, 6.8, or 5.5:1. Feed intakes were not affected (P greater than .20) by dietary S level. Quadratic increases (P less than .05) to S supplementation were observed in grease and clean mohair production, grease and clean staple strength, and staple length. Mohair diameter, med fiber, kemp fiber, S, and cysteine contents were not affected (P greater than .05) by supplemental S. Averaged across the prefeeding, 2, 4, and 6 h postprandial sampling times, ruminal pH, ammonia N, total S, organic S, protein S, and plasma urea N and organic S concentrations were quadratically increased (P less than .05) by supplemental S. Ruminal sulfate S, total sulfide S, and plasma sulfate S were linearly increased (P less than .05) by supplemental S. Retention of N and mohair S yield exhibited quadratic increases (P less than .05), but S retention exhibited a linear increase (P less than .001) with increased S intake. Calculated by regression, the optimum dietary S concentration for maximum clean mohair production was .267% of dietary DM for a N:S ratio of 7.2:1, suggesting that the National Research Council N:S ratio of 10:1 is inadequate for Angora goats. The optimum level of digestible S was calculated to be .18% of the diet DM.


Responses of serum folates of preruminant and ruminant calves to a dietary supplement of folic acid. The effect of dietary supplemental folic acid on serum folates of preruminant and ruminant calves was studied. In Trial 1, doses of 0, .07, .14, .28, and .56 mg of folic acid per kilogram of BW were added to the milk of preruminant calves. In Trial 2, doses of 0, .5, 1, 2, and 4 mg of folic acid per kilogram of BW were incorporated into the concentrates of ruminant heifers. In the first part of each trial, serum folates were determined in blood samples taken 0, 1, 2, 4, 8, 16 (both trials), and 32 h (Trial 2) after a single meal supplemented with folic acid. In the second part of the two trials, the supplement of folic acid was given in feed during seven consecutive days. Blood samples were taken the day before the trial and subsequently every day during 7 d. In preruminant and ruminant calves, the area under the curve and the peak of concentration of serum folates after a meal increased with the dose ingested (P less than or equal to .05, linear and quadratic effect of doses, respectively) but the amount of folic acid needed to obtain a similar response was lower for preruminant than for ruminant calves. In preruminants, the time to reach the maximal concentration was 3 to 4 h after the meal, whatever the dose ingested (P less than or equal to .05), whereas in ruminants this time decreased with the dose ingested (quadratic effect of treatment, P less than or equal to .05).(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of compensatory growth on some body component weights and on carcass and noncarcass composition of growing lambs. A trial was conducted in 1983 and repeated in 1984 to measure effects of restricted feed intake and realimentation on weights of organs and on carcass and noncarcass composition. A total of one hundred six weaned lambs from two breeds (Timahdit and D'man) and a breed cross (Ile de France x D'man) were used in both years. Lambs were allotted to one of six feed intake regimens: HH (ad libitum access to feed from 21 to 30 kg); HM (ad libitum access to feed from 21 to 26 kg then 70% ad libitum to 30 kg); MH (70% ad libitum from 21 to 26 kg then ad libitum to 30 kg); MM (70% ad libitum from 21 to 30 kg); LH (restricted to lose weight from 21 to 17 kg then ad libitum to 30 kg); and LM (restricted to lose weight from 21 to 17 kg then 70% ad libitum to 30 kg). Weights of visceral organs and mesenteric and kidney fat showed dramatic responses to alteration of feed allowances. After recovery from 20% live weight loss, weight of liver equaled or exceeded that of both the ad libitum and 70% refed lambs. Mesenteric and kidney fat did not. Refeeding was accompanied by an increase in water (P less than .05) and a decrease in fat (P less than .01) of both carcass and noncarcass components. These results indicate that weight loss of lambs incurred during feed shortage was largely in internal organ weights, and that these lambs can recover these losses during realimentation and undergo compensatory growth with better feed efficiency and lean carcasses.


Effects of undernutrition and refeeding on weights of body parts and chemical components of growing Moroccan lambs. Forty-four intact, male lambs (20 Timahdit and 24 D'man) were used to assess the effects of 22% (from approximately 25 to approximately 20 kg) and 31% (from approximately 25 to approximately 17 kg) live weight loss and the subsequent refeeding to initial BW on changes in body components. Body composition was determined using a serial slaughter technique at 17, 20, and 25 kg live weight during normal growth, weight loss, and refeeding phases. Reduction in live weight from 25 to 20 kg was associated with greater loss of visceral organs (30%) and internal fat (75%) than carcass loss (19%). Further body weight loss (from 20 to 17 kg) involved carcasses to a greater extent than internal organs. The composition of BW loss consisted of 53% water, 28% fat, and 15% protein. Refeeding was associated with a rapid increase in organ weights and less fat regeneration. Although total internal organs recovered only 90% of their original weight, liver and kidneys regained all their weight. At the same slaughter weight, carcass and noncarcass components of refed lambs were leaner because of lower fat content in these components.


Effect of grain sorghum hybrid on in vitro rate of starch disappearance and finishing performance of ruminants. Forty-eight commercial grain sorghum hybrids were ranked on the basis of in vitro starch disappearance (IVSD) and starch content. Starch content ranged from 64.3 to 70.3% (P less than .01) and IVSD ranged from 5.2 to 6.3%/h (P less than .01). In the next year, 20 experimental grain sorghum hybrids consisting of 17 hybrids being developed for livestock diets and three for human diets were ranked according to IVSD, starch content, and CP content. In these samples, IVSD varied from 6.0 to 9.1%/h (P less than .05). Starch content and CP were not related to IVSD. Starch content was not correlated to CP content. Four of the original 48 grain sorghum hybrids, selected on the basis of IVSD (two fast and two slow), that differed in IVSD by 7.0% (6.5 to 7.0%/h), were fed for 133 d to steers (mean initial BW of 326 kg). The ADG of steers fed Hybrid A (fastest IVSD) was 9.0% faster than that of steers fed Hybrid D (slowest IVSD; 1.33 vs 1.22 kg, P = .06). Gain:feed ratio was positively correlated with IVSD across all treatments (R2 = .94). Hybrids A and D, another Hybrid, A1, and a bird-resistant hybrid (BR) were fed for 85 d to finishing lambs (mean initial BW of 28 kg). Lambs fed Hybrid A gained more efficiently (gain:feed) than those fed BR or A1 (.210 vs .188 and .184, P less than .05), and those fed D were intermediate (.200). Performance of sheep fed A1, with the fastest IVSD, and those fed BR, with the lowest IVSD, were similar, suggesting that factors other than IVSD affected lamb performance. Our data indicate that rate of grain sorghum starch digestion may influence feeding value of grain sorghum fed to cattle.