Effects of feeding dry glycerol to primiparous Holstein dairy cows on follicular development, reproductive performance and metabolic parameters related to fertility during the early post-partum period.

摘要: Contents This study examined the effects of dry glycerol supplementation on follicular growth, post-partum interval to first ovulation, concentration serum metabolites and hormones related fertility, body condition score (BCS) weight (BW) in primiparous Holstein dairy cows. Sixty cows were randomly assigned two groups (control: n = 30 supplemented: 30). Dry (250 g/day/cow) was fed as a top dressing common lactating total mixed ration (TMR) from parturition 21 days post-partum. Ovaries four times using ultrasonography 13, 19, 25 36 determine ovarian growth. Concentration determined weekly. Body evaluated weekly weeks 1 5 after parturition, BWs recorded three 1, 11 during experimental period. The had more large follicles (p < 0.0001) corpora lutea (CL) 0.02) compared with control Days ovulation 0.06), oestrus 0.05), services per conception 0.06) open 0.004) positively affected by supplementation. Serum glucose insulin higher glycerol-supplemented 0.1; p 0.06, respectively). Feeding no effect mean concentrations b-hydroxybutyrate, non-esterified fatty acids IGF-1 However, significant differences observed at BHBA 0.02 0.04, respectively) between day calving. glycerol-fed group progesterone 33 0.007) Supplemented lower loss 1–5 calving (0.34 vs 0.41 BCS). In week 13 post-partum, proportion cycling 83.3 69.9% for those which received supplemented or nonsupplemented diet, respectively. These results demonstrated that feeding glucogenic supply may be useful improve negative energy balance reproductive efficiency young calve high requirement energy.