Lehloenya K.C.,University of Pretoria |
Dattena M.,AGRIS Sardegna DIRPA
Small Ruminant Research | Year: 2016
This study evaluated the applicability of the Day 0 superovulation protocol in Boer goats by comparing it to a traditional pFSH protocol. Twenty Boer goat does were allocated into two groups comprising of 10 animals per group. For the Day 0 protocol, does oestrous cycles were synchronized for 9. days and superovulated with pFSH starting 84. h after the termination of progesterone treatment. For the traditional pFSH protocol, the oestrous cycle of does was synchronized for 9. days, followed by superovulation with pFSH initiated 48. h before CIDR withdrawal. For both groups does had two timed cervical inseminations with fresh undiluted semen. Embryos from both groups were flushed on day 6 following AI. The response to superovulation did not differ significantly between treatments but a tendency (P = 0.06) was found for both fertilization and number of unfertilized ova in favour of the Day 0 protocol. The number of follicles 2-3. mm, 4-5. mm and total number of follicles at the beginning of a superovulation treatment was positively correlated to the total number of structures and embryos recovered. It is therefore concluded that the Day 0 protocol can be used for superovulation in Boer goat does however, more studies with large number of animals are recommended to ascertain its benefits. The correlation results suggest that the response to superovulation and quality of embryos recovered could be more determine by the size and number of follicles at the beginning of a superovulation treatment. © 2016 Elsevier B.V.
Dattena M.,AGRIS Sardegna DIRPA |
Mayorga I.,AGRIS Sardegna DIRPA |
Mara L.,AGRIS Sardegna DIRPA |
Gallus M.,AGRIS Sardegna DIRPA |
And 3 more authors.
EAAP Scientific Series | Year: 2012
Sheep artificial insemination (AI) programs use hormonal treatments to synchronize ovarian cycles and ovulation, but these methods cannot be used on organic farms, limiting potential genetic improvement. This work reports the use of AI during a 3 year period (2008-2010) on an organic Sardinian sheep farm (40°44'6" N) using controlled reproduction management without hormonal treatment. Every year 60 Sarda sheep were isolated from the males at the end of March for 6 weeks. Each animal had daily access to natural pasture and 450-600 gr of concentrate. Five teaser rams were introduced in the flock during the second week of May (Day 0) to induce synchronization and ovulation, and were left there until the start of the presumptive first oestrus (Day 17th). From day 15 to 25, ewes were checked for oestrus 4 times a day (8:00 AM; 12:00 PM; 4:00 PM; 8:00 PM) using teaser rams. The females in heat detected at 12:00 PM; 4:00 PM; 8:00 PM were inseminated by cervical AI 24 h after oestrus detection with fresh semen chilled to 15 °C (400 million spermatozoa/ dose). The percentage of females in heat between day 15 and 25 was calculated for each of the three years. Lambing and prolificacy rates were calculated for years 2008, 2009 and 2010. Throughout the 3 years, 83% of the females were detected in heat. The fertility rate of the 125 artificially inseminated animals was 46.4%. The prolificacy rate of the 58 ewes that lambed was 129.3%. These data show that alternative reproduction management might achieve results comparable to more traditional reproduction programs in Sarda breed.