Estrogen concentration in the feces and blood of full-blood and Polish Horse mares during pregnancy [Polish]

摘要

The study determined the total unconjugated estrogen concentration in the feces of 17 full-blood mares (Equus caballus sp:) and 13 Polish Horses mares (Equus caballus gmelini s. gmelini silvatica) during pregnancy and compared it with the profile of these estrogens in the blood plasma. Fecal and blood samples were collected once a week until day 120 of pregnancy and from day 120 of pregnancy to parturition once every two weeks. The total unconjugated estrogen concentration in the feces and blood plasma was measured by radioimmunoassay (RIA) with extraction: The first increase of the estrogen level in the feces and blood plasma was observed about week 16 of pregnancy: The maximum concentration of this hormone was obtained at week 25 of pregnancy and remained on a high level up until week 40. After this there was a gradual decrease of estrogen levels until parturition. The fecal and blood estrogen levels were similar during pregnancy, but their concentration in feces was 200 times higher than in the blood plasma: The comparative concentration of this hormone was similar in the mares of both breeds. A statistically significant difference in the average estrogen level was observed only during some phases of pregnancy; however this seems to be of little biological importance.-The unconjugated estrogen level in feces reflects its production and metabolism during pregnancy in mares. The results of the study suggest that this method can be used to diagnose physiological and pathological pregnancy in the Equidae family.