Herring fish belong to the family Clupeidae, which contains nearly 200 species. They are small, streamlined schooling fish that feed on plankton and live in both freshwater and saltwater.Herring have a single dorsal fin and protruding lower jaws and are silvery in color.erring fish belong to the family Clupeidae, which contains nearly 200 species. They are small, streamlined schooling fish that feed on plankton and live in both freshwater and saltwater.
DRUG DESCRIPTION. ESTRINGÂ® (estradiol vaginal ring) is a slightly opaque ring with a whitish core containing a drug reservoir of 2 mg estradiol. Estradiol, silicone polymers and barium sulfate are combined to form the ring.hen placed in the vagina, ESTRING releases estradiol, approximately 7.5 mcg per 24 hours, in a consistent stable manner over 90 days. ESTRING (estradiol vaginal ring) has the following dimensions: outer diameter 55 mm; cross-sectional diameter 9 mm; core diameter 2 mm.
see stallion ring. stallion used to detect those mares which are in estrus. During the breeding season those mares to be bred are brought into a crush and the teaser brought alongside. The mares that show estral signs are kept back, usually palpated per rectum to determine the state of their ovaries, and may be bred.