Use of milk progesterone enzyme immunoassay for early pregnancy diagnosis in cows.
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.
Nakao
T
T
Department of Veterinary Obstetrics and Gynecology, School of Veterinary Medicine, College of Dairying, Rakunogakuen University Nishinopporo, Ebetsu-shi, Hokkaido 069-01, Japan.
Sugihashi
A
A
Ishibashi
Y
Y
Tosa
E
E
Nakagawa
Y
Y
Yuto
H
H
Nomura
T
T
Ohe
T
T
Ishimi
S
S
Takahashi
H
H
Koiwa
M
M
Tsunoda
N
N
Kawata
K
K