The Effects of Different Levels of Sunflower Hulls on Reproductive Performance of Yearly Ewes Fed with Pelleted Complete Diets

In this study, 84 pregnant ewes were used and randomly distributed to one of four treatments, as follows: C (control), total mixed ration (TMR) +12% SFH (S12), TMR +20% SFH (S20), and TMR +28% SFH (S28). Treatments had a significant (p < 0.05) effect on the daily feed intake (DFI) of the ewes during the late gestation (30 d prepartum) and post-partum period, with the S12 and S20 groups having lower feed intake (35; 60%) than the C and S28 group. The DFI was significantly (p < 0.05) low during late gestation in comparable with other periods. The results revealed that body weight (BW) at late gestation was significantly (p < 0.05) higher than the BW at 60-days postpartum and during the mating period. Body condition score (BCS) was significantly (p < 0.05) higher during late gestation in comparison with other periods. There was no significant effect of different levels of SFH on reproductive parameters except S/C, which was significantly higher in the S20 than other groups. Serum glucose level was significantly (p < 0.05) higher in the S20 group than the C, S12, and S28 groups during 30 days postpartum. S20 and S28 groups showed a significant (p < 0.05) increase in glucose levels at parturition in comparison with other reproductive periods. At late gestation, a significantly (p < 0.01) higher concentration of blood NEFA was reported for ewes from the C group compared with other groups. Furthermore, significantly lower (p < 0.05) NEFA levels at parturition were found for ewes from the S20 group compared with the S12 group. In conclusion, TMR is not preferable to be used alone in the late gestation period. Sunflower hull can be used as a cheap source of fiber in TMR without adverse effects on health or the reproductive traits of ewes. The increasing level of sunflower hull up to 28% can affect fertility and increase the number of services per conception, probably due to its high content of lignin (phytoestrogen).