Influence of feed restriction on chromosomal pictures, some biochemical parameters and spermiogram of Crossbred rams

The goal of the present study is to evaluate the effect of feed restriction on chromosomal pictures, serum biochemical parameters and some hormones in addition to spermiogram with their reflection on the reproductive efficiency of rams. Five mature Crossbred [Barki x Rahmani] rams were used, their age ranged from 15 to 17 months and weighting 45 to 60 kg. Rams received a basal diet according to the management of Animal Reproduction Research Institute [ARRI]. The animals were exposed to 21 days of feed restriction [1/3 amount of basal diet]. Restricted rams refed again on basal diet for 14 days. Blood and semen samples were collected from rams [before feed restriction, 21 days after feed restriction and 14 days post refeeding]. The results showed that there were significant differences between first period and others in the percentage of some chromosomal abnormalities which mainly were polydiploidy, in addition to gaps, breaks, deletions and fragments which increased significantly only after feed restricted periods in addition to the significant increase in the percent of total number of aberrated cells. Concerning the biochemical parameters, there was a significant decrease in serum glucose and cholesterol levels after feed restriction and they were elevated after refeeding to their levels before the restriction. Malondialdehyde showed a significant decrease after refeeding than the other two periods of the experiment. On the contrary, there was a significant increase in serum insulin levels after feed restriction compared with the other two periods. The effect of feed restriction was clear on serum testosterone hormone level which showed significant decrease after feed restriction and after refeeding. There was significant decrease in semen volume after restriction and refeeding rams. There was significant decrease in the motility and live/dead sperm after feed restriction and return to their levels post refeeding. Concentration of semen showed significant decrease after both feed restriction and refeeding. Total sperm abnormalities showed significant increase after restriction and back to first level before restriction. It was concluded that, feed restriction [l/3 amount of basal ration] for 21 days in mature rams has adverse effect on the chromosomal pictures, some biochemical parameters and decreased testosterone level in addition to decrease in all semen parameters. This effect was not overcome by supplemental feeding again that confirming the status of these rams did not improve completely even after the tested refeeding period

Effect of calcium soaps of fatty acids and recombinant bovine somatotropin on productive and reproductive performance of baladi goats during early lactation

This study examined the mechanism by which calcium soaps of long chain of fatty acids [CSFA] and recombinant bovine Somatotropin [rbST] affect production and reproduction of Baladi goats [does]. The present study was carried out on 16 multiparous pregnant Baladi does aged 2.5 - 3 years. The treatments were initiated approximately four weeks before lambing until eight weeks post-lambing. Animals received 1 kg /head/day basal diet and allocated into four groups [n = 4 does /group]: without any treatment [control group I], plus 50 gm/head/day of CSFA [group II], 1 mg /kg body weight of rbST S/C injection every 14 days [group III], or a combination of CSFA supplementation and rbST injection [group IV]. It was found that a significantly shorter mean intervals [days] from lambing to first luteal activity and to conception and a higher percentage of ovarian cyclicity [100%] in group II and IV than in group I and III [75%]. Conception rate was also higher in group II and IV [100%] than group III [75%] and I [50%]. All kids of the treated groups had a significantly increase in their birth and weaning weights when compared with those from control group. There were significant increases in serum insulin in group II and IV and in serum leptin in all treated groups throughout the trial. Prolactin concentration was significantly higher in all treated groups than in the control one especially in rbST injected does. Also serum progesterone level showed a significant increase in all treated groups. Meanwhile, there was a significant effect of CSFA and rbST on T3 level during the first two weeks only of post-partum period and on T4 at day of lambing and during the second month of post-partum period. There was a significant increase in milk fat in all treated groups than control one, but showed highly significant increase in groups II and IV than in group III. Meanwhile, there was a non-significant effect of treatments on percentage of milk protein, total solids or solid not fat throughout the trial. In addition, there was a significant decrease in milk urea content in the three treated groups than in the control group. In conclusion, using of CSFA and rbST have a positive effect on lamb performance and milk composition. Meanwhile, CSFA supplementation has a more positive effect on reproductive performance, lamb performance and milk composition than injection of rbST. So, we recommend that using CSFA for does during late pregnancy and early post-partum period as a feed supplement at a level of 50 gm/head/day to improve reproductive performance, enhance metabolic profile, enhance lamb performance [in terms of birth weight, weaning weight and growth rate] and improve milk quantity and quality