Ovarian follicular response to oestrous synchronisation and induction of ovulation in Norwegian Red cattle.

ABSTRACT: BACKGROUND:Oestrous synchronisation of cattle has been widely applied to accomplish simultaneous ovulation in animals and facilitate timed artificial insemination. The main aim of this study was to investigate the ovarian follicular growth and ovulatory response to oestrus and ovulation synchronisation in Norwegian Red heifers and cows. Oestrous cycles in 34 heifers and 10 cows from 4 herds were synchronised with two PGF2α analogue treatments 11 days apart, followed by GnRH analogue treatment for induction of ovulation. Thereafter, the ovaries were examined by ultrasonography at 3 h intervals until ovulation. RESULTS:The luteolytic effect of the PGF2α analogue was verified in 9 of 10 cows by progesterone contents in milk. Maximum physical activity of the cows occurred on average 69 h after

SUBMITTER: Berg HF 

PROVIDER: S-EPMC7068941 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature