The Relation Between Oxidative Status, Milk Quality and Conception Rate in Dairy Goats Supplemented With Vitamin C

Abstract

Pregnant Agamy does were used in this experiment to evaluate the effects of Vitamin C (Vit C) supplementation as antioxidant agent to improve the performance of dairy goats during the evidence of oxidative stress (OS) in peri-parturient period. The does under experiment (n = 16) were assigned randomly into control and supplemented groups (n = 8 / group). The control group fed control diet without supplement and the supplemented group fed control diet plus Vit C 75mg/kg of body weight. Dietary supplementation began approximately one month before the expected kidding date till two months post-kidding. Compared to the control does, it was noticed that Vit C supplementation significantly increased (P<0.05) the conception rate (62.5 % vs. 25 %), the weaning weight (WW) (7.21 vs. 5.00 kg) as well as the average daily gain rate (DGR) (53.94 vs. 34.85 g/d) in the kids of the Vit C supplemented group. Vit C supplementation significantly (P<0.05) increased serum level of T 3 from day 45 to day 60 and of T 4 from day 30 to day 60 postkidding. Meanwhile, serum cortisol level was significantly decreased (P<0.05) from day 30 to day 60 post-kidding in the Vit C supplemented group. Also, there was a significant increase (P<0.05) in serum total antioxidant capacity (TAC) from day 15 post-kidding and glutathione peroxidase (GPX) from day 30 post-kidding till the end of the experiment in the Vit C supplemented group as compared with the control one. Meanwhile, there was a significantly decrease (P<0.05) in serum Malondialdehyde (MDA) level from day 45 post-kidding and nitric oxide (NO) level from day 15 post-kidding till the end of the experiment. Concerning the effect of Vit C supplementation on milk quality, it was found that Vit C supplementation significantly (P<0.05) improved most of milk components especially fat, lactose, milk urea level (MUL), total solids (TS) and solid not fat (SNF); meanwhile there was a non-significant increase in protein % all over the experiment period. Moreover, both somatic cell counts (SCC) and the infection rates represented by the total bacterial count (TBC) were significantly (P<0.05) decreased in the Vit C supplemented group when compared with the control one. It was concluded that Vit C supplementation in dairy does around the peri-parturient period can improve the unfavorable effects of OS; this reflected on their milk quality and post-kidding conception rate and enhancement of growth rate as well as weaning weight of their kids.

Effect of Vitamins and Hormones during different stages of Lactation in Lohi Sheep and Beetal Goats

“…The findings of present study agree with that of Ognik et al (2015) who had reported that there was no change in Vitamin C concentration during various stages of lactation. Howida et al (2015) concluded that vitamin C supplementation enhanced to the adverse effects of oxidative stress and improved milk quality. The reason for low T 3 and T 4 could be breakdown of fat and protein in mammary tissue (Riis and Madsen, 1985).…”