The Impact of Pasture Quality on Fertility in Akkaraman Sheep

This study employed Akkaraman sheep aged between 2 and 6 years, with a live weight ranging from 53 to 68 kg, sourced from four farms. Three of these farms utilized the same pasture, while the fourth employed a different one. The pastures where the sheep were grazed were categorized as either poor (Group I) or medium (Group II, III and IV) quality. For estrus synchronization, intravaginal progesterone (P4) impregnated sponges were inserted into ewes in Groups I and II for 9 days during the breeding season, taking into account the ram availability in the facility. PGF2α was administered 2 days before the removal of the sponge and 500 IU PMSG was administered after removal. In Group III, where flushing was applied, barley was given at a rate of 300 g/day per head. In group IV, no treatment was applied. Estrus detection was performed using teaser rams, and then ewes were kept with fertile rams in the same environment. The reproductive performance metrics of ewes across experimental groups were assessed, revealing notable variations. Ewe estrus rates were consistently high, ranging from 88.0% to 98.3%, with Group II exhibiting the highest rate. Similarly, parturition rates ranged from 74.5% to 97.7%, with Group II showing the highest rate. Twin births varied substantially, with Group III displaying the highest rate at 66.4% compared to 11.8% in Group I. Litter size ranged from 1.06 to 1.25. Group III exhibited a higher number of ewes that did not give birth. In both Group II and Group III, superior results were achieved across all parameters checked except for litter size. In Groups I and IV, the infertility rate was higher than in the other groups. However, the litter size of Group IV was still higher than Group I. If flushing is applied together with P4-based synchronization to ewes grazing on medium-quality pasture, fertility should be expected to improve significantly. In this study, the comparison was made between the effects of pasture on fertility with P4 application, and the effects of P4 and flushing on fertility in farms utilizing the same pasture.