| Popis: |
Background: Little is known about the temporal relationships between reproductive hormones around oestrus and embryo survival in pigs. Some sows that have been inseminated and are transferred to the gestation units will return to oestrus either because they did not conceive at first service or because they abort during gestation. Aim: This study aims to investigate the effect of pig breeds on fertility rates of Southern African indigenous sows Methodologies: Mukota, Windsnyer and Kolbroek pigs’ breeds were subjected to sexual preparation procedures of 0MR, 5MR, 10MR, 15MR, 20MR and 25MR. Sows were inseminated with semen from sexually prepared boars and analysed for fertility rates. Results: Litter size was increased with the afternoon (14:30) protocols in all the breeds studied, with significantly (P˂0.05) highest improvement in Windsnyer breed. There were significant improvement in proportions of the litter size amongst experimental groups compared to control groups during the morning (08:30) and afternoon. Farrowing rate was observed higher in Kolbroek (87.50%) followed by Mukota (68.75%) and then Windsnyer (56.25%). Overall, the total average farrowing rate in Southern African indigenous pig breeds studied was observed to be at 70.83%. Total average weaning rate was observed in this at 87.50% for all studied breeds. Discussion: Reproductive traits are of major importance especially in dam breeds of pigs because the reproductive performance of sows is one of the major factors of the breed effectiveness in pig breeding. The breed type has an influence on the willingness of the animal to copulate. Conclusion: Litter size was recorded to have improved with the highest in all studied breeds following 10MR in the afternoon. Moreover, farrowing and weaning rates improved with Mukota recording the highest followed by Kolbroek then Windsnyer. |
