Study On Sectional Mechanism Of Rumen Nutrition Manipulation And Control--The Effect Of Supplemental Niacin And Ca-LCFA In Diet On Cattle Nutrition Metabolism

Three (two in trial two) ruminal cannulated adult Chinese yellow cattle were used in this study. Trial one was defined niacin group and trial two was Ca-LCFA group. Both trial were divided into three periods, trial one included control group feeding basal diet (concentrate and rice straw, ME 5. 35 Meal/Kg, CP 16. 78%) and treat I II feeding basal diet adding supplemental 6g/d and 12 g/d niacin, Trial two' included control group feeding basal diet(the same one with trial one), and treat III TV feeding basal diet added supplemental 8% Ca-LCFA and 8% Ca-LCFA adding 20g/d niacinThe results of this study showed that: supplemental 6g/d niacin increased significantly 24h, 36h, 48h in sacco degradability of DM of soybean meal(P<0.01), effective degradability of DM of alfalfa hay(P<0. 05), 2h, 36h, 48h(P<0.05) and 6h, 12h, 24h degradability and effective degradability of CP of concentrate(P<0.01), 12h, 48h degradability of CP of rice straw, and 24h(P<0.05), 36h(P<0. 01) degradability of NDF of soybean meal. Supplemental 12g/d niacin decreased significantly 48h degradability and effective degradability of CP of rice straw(P<0. 05) and 24h, 36h degradability of NDF of alfalfa hay (P<0.05). Supplemental Ca-LCFA increased significantly 24h(P<0.01), 36h(P<0.05) degradability of CP of soybean meal, 36h, 48h(P<0. 05) degradability of NDF of soybean meal , 6h(P<0. 01), 12h(P<0. 05) degradability of CP of rice straw, decreased significantly 6h, 36h degradability of DM of rice straw(P<0. 05) and 36h, 48h, 72h degradability of NDF of rice straw (P<0.05). Treat IV promoted degardation of DM of concentrate , increased degradation of CP of rice straw more than treat III, alleviated the inhibit effect of treat III on DM and NDF of rice straw, hut decreased significantly 24h degrability of NDF of corn(P<0.05).In terms of the effect of supplemental niacin and Ca-LCFA on rumenprotozoal number, treat I and treat II increased significantly protozoal number (P<0. 05), treat III had a trend of decreasing protozoal number (P<0. 10), treat IV decreased significantly protozoal number(P<0.05). Treat I and treat II had a trend of increasing the number of Entodinium(P<0.10), treat II increased significantly the number of Diplodinium(P<0.05), the number of Isotyicha of treat I was higher significantly than control (P<0. 01) and treat II (P<0. 05).Treat II decreased significantly rumen pH(P<0.05), The NH3-N concentration of treat III had a higher trend than that of treat IV (P<0. 10).The CP digestibility of gastrointestinal of treat I had a higher trend than that of treat II (P<0. 10), the NDF digestibility of treat I had a lower trend than that of control (P<0. 10), the blood fat concentration of treat I and treat IV had a higher trend than that of control (P<0.10), The blood glucose concentration of treat III had a higher trend than that of control(P<0. 10).