Ultrasonography I: Development of Ovarian Follicles in Boer Goats Superovulated with pFSH Containing 40% pLH

Abstract

Response of oestrus in Boer goats and development of ovarian follicle to superovulatory treatment were studied. All goats (n=17) received subcutaneous progesterone ear implant for 11 days to synchronize oestrus cycle. Forty eight hours before implant removal and the following 3 days. 16 AU pFSH containing 40 % pLH was injected 6 times (4, 4; 2, 2; 2, 2) in 12 h intervals. Goats received PGFZ, twice synchronized with FSH treatments to induce luteolysis (5 mg PGF2, of each) 24 h after implant removal. Animals were checked for oestrus with an aproned buck 3 times a day. During standing oestrus animals were naturally mated 2 or 3 times. Follicular development and ovulation were monitored 2 times a day using transrectal ultrasonography equipped with a 7.5 MHz linear-array trunsducer. This evaluation began from the time of implant removal until 48 h after the end of oestrus. Eighty eight per cent of animal showed oestrus with mean of the onset of oestrus 33 h after implant removal and oestrus duration of 30 h. Eighty two percent of does had corpora lutea with number of 1 1,O and persistent follicles of 2.1 at laparoscopic examination on day 6 after the end of oestrus. The maximum number of follicles with diameter > 2 mm recorded at the observation of 36 and 48 h after implant removal, whereas those with 2 6 mm in diameter were 48 - 60 h. The number of follicles with diameter 2 - 3 mm and 4 - 5 mm during observation period were constant. The ovulation of follicles did not occur spontaneously but they ovulated in several periods. The pFSH+ 40 % pLH preparation yielded a sufficient result for superovulation means in Boer goats. For monitoring the response of ovaries to the superovulatory treatment, ultrasonography was a simple and effective method.