title: Use of milk progesterone enzyme immunoassay for early pregnancy diagnosis in cows.
abstract: An enzyme immunoassay using beta-galactosidase as the tracer was applied to determine milk progesterone level in cows. The novel method was reliable and practicable and required only a spectrophotometer and a centrifuge as major equipment. The milk progesterone enzyme immunoassay successfully diagnosed early pregnancy in cows. Milk samples were collected from 268 Holstein-Friesian cows in commercial dairy herds on 20, 21 or 22 days(usually 21 days) after insemination. Progesterone level in skim milk higher than 1.0 ng/ml indi-cated pregnancy. Pregnancy was confirmed by rectal palpation on 60 to 120 days after insemination. The accuracy of the milk progesterone test was 60.0 % (132 220 ) for a positive diagnosis and 100 % (48 48 ) for a negative result. A high incidence of embryonic death, 27.9 % (51 183 ), may have reduced accuracy for a positive test result. The enzyme immunoassay may be an alternative to radioimmunoassay in milk progesterone analysis for pregnancy diagnosis.
authors.affiliation: Department of Veterinary Obstetrics and Gynecology, School of Veterinary Medicine, College of Dairying, Rakunogakuen University Nishinopporo, Ebetsu-shi, Hokkaido 069-01, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakao
authors.forename: A
authors.initials: A
authors.lastname: Sugihashi
authors.forename: Y
authors.initials: Y
authors.lastname: Ishibashi
authors.forename: E
authors.initials: E
authors.lastname: Tosa
authors.forename: Y
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: H
authors.initials: H
authors.lastname: Yuto
authors.forename: T
authors.initials: T
authors.lastname: Nomura
authors.forename: T
authors.initials: T
authors.lastname: Ohe
authors.forename: S
authors.initials: S
authors.lastname: Ishimi
authors.forename: H
authors.initials: H
authors.lastname: Takahashi
authors.forename: M
authors.initials: M
authors.lastname: Koiwa
authors.forename: N
authors.initials: N
authors.lastname: Tsunoda
authors.forename: K
authors.initials: K
authors.lastname: Kawata