Effect of different dietary energy levels on the reproductive performance of Kivircik sheep under a semi-intensive system in the South-Marmara region of Turkey

Abstract

The objective of the study was to determine the effects of four dietary energy levels (L1 - 10.3, L2 - 11.0, L3- 11.6 and L4- 12.2 MJ ME per kg DM) on oestrus synchronization and fertility in Kivircik ewes. Eighty Kivircik ewes were randomly allocated in equal numbers to the four dietary energy treatments. The groups were treated with intra vaginal sponges containing 40 mg FGA (fluorogestone acetate) for a period of 14 days and 500 IU pregnant mare serum gonadotropin was injected intramuscularly after sponge withdrawal. The proportion of ewes exhibiting overt oestrus within 96 h after the injection was significantly lower (P<0.05) in the L1 and L2 eves (86 and 89 %) than in those on the L3 (100%) and L4 (100%) treatments, respectively. Mean litter size and fecundity were higher (P