Effects Of Fumarate Supplementation On Ruminal Fermentation,Energy Metabolism And Reproductive Hormones In Late Pregnancy Goat

The aim of this study was to investigate the effects of fumarate supplementation on rumen feremtnation, energy use efficiency and reproduction performance in late pregency goats. The study was further divided into two experiments of in vitro ruminal incubation and animal trial.Experiment 1 is in vitro ruminal incubation. Rumen fluid was collected from three adult Xiangdong black goats through permanent rumen fistulas. The study contained control groups (A without any treatments), Fumarate groups (Fumarate contents of F1, F2 and F3 were 1.5,4.5 and 9.0 mM respectively). The 72 h in vitro ruminal incubation was performed to study the formarate supplementation on ruminal fermentation based on kinentics of total gas production, hydrogen gas and methane production, and volatile fatty acids profile.The results showed that:increasing supplementations of fumarate linearly (P< 0.05) increased the Potential maximum gas production, gas production,initial fractional rate of degradation, propionate, butyrate and total volatile fatty acids production, while rate of gas production and the ratio of acetate to propionate linearly decreased (P< 0.05). Fumarate supplementation had no significant (P> 0.05) effect on pH value, methane and hydrogen gas production in comparison with control group.Our study indicated that fumarate supplementation could enhance the initial fractional rate of degradation, thus may help to increase feed degradation, digestion and utilization in ruminants, Furthermore, fumarate supplementation could alter pattern of rumen fermentation through facilitating propionate production.Experiment 2 is in vivo animal trial.Fifty healthy female goats were selected with similar body weight, treated by estrus synchronization and insemination. The animal trial started on 90 d after pregnancy, and further divided into two groups. The control group was fed with basal diet, while experimental group was fed with basal diet supplemented 40g/day fumarate.Effects of fumarate on the goats feed intake, digestibility and energy balance were investigated, while the blood was collected to determine biochemicial variables, antioxidation status and hormonal.The results showed that fumarate supplementation had little effect (P> 0.05) on feed intake, total tract digestibility of feed and energy, and body weigh (P< 0.05). Fumarate supplementations could also significantly (P< 0.05) increased hemoglobin, prolactin, cortisol and progesterone concentration, and decreased (P< 0.05) estradiol and estriol concentration, in comparison with control group. Our study indicated that fumarate supplementation had little effect on energy use effieciency of late pregency goats, the change of reproductive hormones in late pregnancy goats are not by raising the energy utilization efficiency of feed change.