title: Peripheral plasma progesterone concentration in zebu (Bos indicus) cows during pregnancy.
abstract: Plasma progesterone concentrations were determined weekly during gestation averaging 283 +/- 2 d in Ethiopian zebu (Bos indicus) cows. Mean progesterone levels increased from 0.2 +/- 0.1 ng/ml at oestrus (service) to 3.1 +/- 1.6 ng/ml on d 7 and 8.1 +/- 2.1 ng/ml on d 21. Progesterone levels remained elevated throughout pregnancy. Hormone concentration differed significantly between cows (P less than 0.001) and with the wk of pregnancy (P less than 0.05); it tended to be higher during the last trimester of pregnancy. Mean levels dropped sharply to below 1 ng/ml during the last wk of pregnancy with considerable variation (C.V. = 39 to 63%) among cows. These data indicate that pregnancy in Ethiopian zebu cows can be reliably diagnosed by determining circulatory plasma progesterone levels.
authors.affiliation: Animal Reproduction and Health Section, International Livestock Center for Africa, Addis Ababa, Ethiopia.
authors.forename: E
authors.initials: E
authors.lastname: Mukasa-Mugerwa
authors.forename: A
authors.initials: A
authors.lastname: Tegegne
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000097:blood*; D011374:Progesterone / Q000097:blood*; D013997:Time Factors
chemical_list: D011374:Progesterone