This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by LAND, R. B. Articles by McGOVERN, P. T. Search for Related Content PubMed PubMed Citation Articles by LAND, R. B. Articles by McGOVERN, P. T.

OVULATION AND FERTILIZATION IN THE LAMB

The experiments described below were undertaken to study the effects of different hormone treatments on follicular development, ovulation and fertilization in lambs. In a similar investigation, Mansour (1959) obtained a low rate of fertilization which he attributed to the use of diluted semen and to the inefficiency of insemination by the vaginal route. In the present experiments fresh undiluted semen was introduced directly into the uterine horns.

Sixteen Scottish Blackface and eight crossbred female lambs were used. The average weight was 16·7 kg (range 11·5 to 26·5 kg). The treatments were begun (Day 0) as soon as possible after the lambs were 50 days of age so that ovulation would be expected to occur when the lambs were approximately 9 weeks old.

The treatments were: (a) Daily administration of 3·0 mg progesterone ('Protormone'; Burroughs Wellcome & Co.) by