1 Cats: Cats normally have their first estrous cycle between 4 and 6 months of age, with the average age around 5 months. 2  The female cat has 2-4 estrous periods every year, each lasting 15-22 days. 3  If she is bred, estrus seldom lasts more than 4 days.
Lactate dehydrogenase (LD or LDH) is an enzyme involved in energy production that is found in almost all of the body's cells, with the highest levels found in the cells of the heart, liver, muscles, kidneys, lungs, and in blood cells; bacteria also produce LD.actate dehydrogenase (LD or LDH) is an enzyme involved in energy production that is found in almost all of the body's cells, with the highest levels found in the cells of the heart, liver, muscles, kidneys, lungs, and in blood cells; bacteria also produce LD.
Lactate, also known as lactic acid, is a metabolic product. In animal cells it is produced by the modification of pyruvate by lactate dehydrogenase. Some bacteria, such as lactobacillus, also produce it as an end-product of metabolism. However, lactate can be used by cells to regenerate other compounds via several different biochemical pathways.