Effects Of Processed Corns On Rumen Fermentation,Nutrient Digestion And Metabolism In Sheep

Experiments were designed to study sheep rumen degradation regularity of DM and starch of corns treated in different ways by in situ technique. Digestion and metabolism trails were adopted to investigate the effects of processed corns on nutrients digestibility and N metabolism in sheep. Changes of rumen fermentative indexes were also observed. The objective of this experiment is to investigate the effects of processed corns on rumen fermentation ~. nutrient digestion and metabolism as well as animal performance. Trail 1: Effects of processed corns on rumen degradation of corn DM and starch in sheep. Four Inner Mongolia semi-fine wool wethers fitted with permanent cannules at the rumen were used in a 4 X 4 latin square experiment to investigate the effects of treated corns (raw, pelleted, toasted, steamed) on sheep rumen digestibility of corn DM and starch, at 1 .3M feeding level base by in situ technique, results showed that soluble fractions (S) of corn starch were 17.8%, 20.99%, 13.05%, 13.55% respectively in raw, pelleted, toasted and steamed corns. The potential degradable fractions of starch (D) were 82.82%, 79.01%, 86.95%, 86.45%, respectively, the rate of degradation (Kd) were 3.19%/h, 4.81%/h, 2.15%/h, 4.35%/h, and the bypass starch were 420.65%/h, 350.46g/Kg, 494.73g/Kg, 388.94g/Kg. The effects of processed corns on the rate of rumen DM and starch degradation was significant (P(0.05) except for DM in the steam group. Trail 2: The effects of processed corns on nutrients digestibility and indexes of rumen fermentation. Four Inner Mongolia semi-fine wool wethers were selected to investigate the effects of treated corns on nutrient digestibility and index of ruxnen fermentation in the wethers. The mean body weight was 23.7?.4kg and the dietary feeding level was 1 .3M. Processings had no significant effects on the apparent digestibility of DM, CP, ADF,NDF (P>O.05). Pelleting, toasting and steaming had a trend to increase N deposition compared to control group. The NH3-N concentrations in the rumen showed a decreasing tendency but no significant among the groups (P>O.05). Pelleting and steaming increased rumen TVFA production and its ratios. The ratio of acetic acid and propiomc acid was similar to toasting and control group, all belonged to propiomc acid--acetic acid type fermentation.