Effect Of Isoflavonic Phytoestrogens-Daidzein On The Digestion And Metabolism And The Levels Of Relative Hormones Of Goats

The experiment studied the effect intraduodenal infusion of Daidzein on the digestion and metabolism and the levels of relative hormones of goats.Four local non-pregnancy female goats(average weight 20kg and one year old) fixed with permanent rumen fistulas^ duodenal cannula and temporary juglar vein catheter were used in the experiment. The study was divided two periods which had been made composition by themselves. The two periods all were twelve days. About 5ml physiological saline was infused into duodenum in control periods, the suspended liquid which mixed with Daidzein and physiological saline(including Daidzein 200mg)was infused into duodenum in treatment periods..The result of rumen fluid showed that intraduodenal infusion of Daidzein increased rumen fluid pH value(P<0.05), protein content of bacterial protein(B-P) and ammonia nitrogen(NH3-N) concentration significantly(P<0. 01); the protein content of rumen fluid trichloroacetic acid protein(TCA-P) and protozoal protein(P-P) tended to be higher than that of control period(P>0.05). The concentration of total volatile fatty acid(TVFA) and the percentage of acetic acid in rumen fluid all increased significantly(P<0. 01), the percentage of acetic acid tended to be lower (P>0.05), the percentage -of butyric acid decreased significantly (P<0. 01), C2/C3(A/P) rate decreased from 3.84 for control to 1.83 for treatment. This suggests that Daidaein can increase the synthesis capacity of ruminal microbial crude protein and alter the rumen fermentation pattern, tend to propionic-type fermentation.The result of duodenal digesta showed that intraduodenal infusion of Daidzein can increase the flow of digesta, ammonia nitrogen concentration and microbical nitrogen content significantly(P<0. 01), but the total nitrogen and Urea nitrogen (P>0.05)> Non-ammonia nitrogen and by-pass protein nitrogen (P<0.05) all decreased. Total ammonia acid content * necessary ammonia acid content (P>0. 05) and Non-necessary ammonia acid content (P<0.05) all increased by 35.95%, 39.26% and 30.22% compared with those of the control period, the asparagine(Asn), valine(Val), isoleucine(Ile) and leucine(Leu) also increased by 54. 17%, 37. 92%, 36.18% and 45. 35%(P<0. 05) compared with those of the control period.Those results indictated that Daidzein can increase the recycle capacity of Urea and the regeneration capacity of protein of goat and increase the MCP and Non-necessary ammonia acid contents in duodenal digesta. The result of relative hormones in blood show that intraduodenal infusion of Daidzein can increase the levels of T3, T4, GH, E2 in blood significantly(P<0. 01), they all increased by 128. 57% , 124. 12%, 106. 49% and 72. 34%. Those results indicated that Daidzein can regulate the growth and ruminal digestion and metabolism of ruminant indirectly through regulating the levels of endogenous hormones.