摘要
The current study assesses the ram effect as an alternative to conventional hormonal treatment for estrus synchronization prior to artificial insemination. Two groups of 50 anoestrus Sarda ewes were induced to ovulate with adult rams (RE group) or synchronized using intravaginal sponges impregnated with progestogen and equine chorionic gonadotropin (eCG) (PRO group). Ewes in the RE group were isolated from rams for 6 weeks. After the isolation period, 5 vasectomized rams were introduced into the flock at a ratio of 1 ram/10 females (day 0) to induce estrus and ovulation. Ewes in both experimental groups were inseminated via the cervical route with fresh semen (400 million spermatozoa/0.25 ml) 24 h after the onset of estrus (day 15–24). The pregnancy rate, assessed by ultrasound 35 days after insemination, was 48.9% (24/49) and 43.47% (22/50) for sheep in RE and PRO groups respectively. Lambing rates were identical to pregnancy rates in both groups, while the prolificacy rate was 120% (59/49) and 130% (65/50) in RE and PRO groups respectively. No significant differences were found between the 2 groups. The data supports the conclusion that the ram effect can be used successfully to synchronize estrus in organic farming operations.
摘要译文
目前的研究评估了ram效应，作为人工授精前发情同步的常规激素治疗的替代方案。用成年公羊（RE组）诱导两组50只无脊椎Sarda母羊排卵或使用浸渍有孕激素和马绒毛膜促性腺激素（eCG）（PRO组）的阴道内海绵同步。 RE组中的母羊从公羊中分离出6周。在分离期后，将5个输精管切除的公羊以1个ram / 10个雌性（第0天）的比例引入到鸡群中以诱导发情和排卵。两只实验组的母羊在发情后24小时（第15-24天）通过宫颈途径用新鲜精液（4亿精子/0.25ml）进行授精。在人工授精后35天通过超声评估的妊娠率分别为RE和PRO组绵羊的48.9％（24/49）和43.47％（22/50）。两组的产羔率与妊娠率相同，而RE组和PRO组的再生率分别为120％（59/49）和130％（65/50）。两组之间未发现显着差异。该数据支持这样的结论：可以成功地使用ram效应来同步有机农业操作中的发情。
IsabelMayorga[a];RekikMourad[b];LauraMara[a];MariliaGallus[a];ZaferUlutaş[c];MariaDattena[a];. Organic breeding in Sarda ewes: Utilization of the ram effect in an artificial insemination program[J]. Small Ruminant Research, 2019,174: 131-134