Pregnancy rate in dry and lactating goats after estrus synchronisation with artificial insemination and natural breeding (a field study)

Abstract

SummaryYotov, S., A. Atanasov, M. Karadaev, L. Dimova & D. Velislavova, 2016. Pregnancy rate in dry and lactating goats after estrus synchronisation with artificial insemination and natural breeding (a field study). Bulg. J. Vet. Med., 19, No 3,[218][219][220][221][222][223] The objective of this study was to determine the pregnancy rate in dry and lactating goats after estrus synchronisation with artificial insemination and natural breeding of unconceived animals. The investigation was conducted with 75 dry (group I) and 32 lactating (group II) local goats in breeding season. All animals were submitted to estrus synchronisation by intravaginal sponges for 12 days, PMSG injection on day of sponge removal and two artificial inseminations (AI) with fresh semen -48 and 56 hours after sponge withdrawal. Two weeks after the AI, daily test for goats which had not conceived after the AI was performed by teaser and the detected animals in estrus were naturally mated with a fertile buck. Ultrasonographic pregnancy examination was carried out at 20-day intervals until day 100 after the AI. The pregnancy rate in artificially inseminated and naturally bred animals and the interestrus intervals were calculated. The pregnancy rate between both synchronised groups differed significantly (P<0.05), while the values in the groups with natural breeding were comparable. Different pregnancy rates between artificially inseminated and naturally bred goats in group I (72% vs. 42.9%) and group II (19% vs. 73%) were registered (P<0.05). Additionally, considerable differences (P<0.05) between the values after first natural breeding (9.6% and 46.6%) were detected. The total pregnancy rate (84%) in dry goats was higher (P<0.05) than that (54%) in lactating animals. The interestrus intervals were similar (P=0.2). In conclusion, the current data could be used for optimisation of the pregnancy rate and the reproductive efficiency in local goat breeds.

Diagnosis of Pregnancy in Iraqi Awassi Ewes Through Progesterone Hormone Measurement and Ultrasonography Following Induction of Fertile Estrus with Sulpiride

“…While, Yotov. [35] demonstrated that accuracy of pregnancy detection was high (87%) at week 4 post-breeding, and it increased to 98% at day 35 post-mating using a 5 MHz transabdominal probe in Satara Zagora sheep breed. The ultrasonography examination method on day 50 can be considered a gold standard for pregnancy diagnosis, given the high diagnostic criteria and reliability recorded (100%) [36].…”

Reproduction in Goats

“…In many cases, the use of the standard technique results in deposition of the semen in the cervix if all the cervical rings cannot be passed. Under controlled conditions, pregnancy rates following the use of the standard technique are low, typically in the range of 20-30% [41][42][43][44].…”

“…The urinary catheter is then repositioned into the opposite uterine horn, and the second half of the semen sample is deposited deep into that horn to complete the insemination. With trained technicians, the entire procedure takes about 5-10 min [41] and does not involve any surgical entry or anesthesia of the doe. Furthermore, pregnancy rates following deep cornual insemination were greater than those for laparoscopic insemination in their study.…”