Effects Of Treating Rice Straw With Different Methods On Rumen Degradation Charateristics And In Vitro Methane Production

Development of animal husbandry and improvement of livestocke product quality depends largely on the quality of straw. Different treated methods can improve the nutritional value of straw,which can make the straw better used by ruminants. At present, the main research of different treated rice straws was evaluated nutritional quality, the relationship between nitrogen and carbohydrate rumen degradation characteristics and adjustment of methane production different treated rice straws was not reported. Based on this, The aim of this study was to investigate the effects of different treated rice straws on the nutrients, rumen degradation characteristics methane emissions and micro flora. The results as follows:Experiment1Studies on different treated rice straws nutrients and rumen degradabilityDM, CP, NDF and ADF contents of different treated rice straws were significantly different. DM contents of dry rice straw was the highest, and the following were alkali treated rice straw, ammonia treated rice straw and rice straw silage. Neutral detergent fiber (NDF) content of dry rice straw was significantly higher than rice straw silage, ammonia treated rice straw and alkali treated rice straw (P<0.05). CP content of ammonia treated rice straw was the highest, followed by rice straw silage. Acid detergent fiber (ADF) content of alkali treated rice straw was significantly higher than dry rice straw, rice straw silage and ammonia treated rice straw (P<0.05). Non-fiber carbohydrare (NFC) contents of alkali treated rice straw and rice straw silage were significantly higher than ammonia treated rice straw and dry rice straw (P<0.05). N/OM of ammonia treated rice straw was the highest, followed by rice straw silage (P<0.05).OM a-part content of rapid degradation of rice straw silage and ammonia treated rice straw were significantly higher than dry rice straw and ammonia treated rice straw, and b-part content of slow degradation of alkali treated rice straw was the highest (P<0.05), ED-value of alkali treated rice straw was significantly higher than those in other three rice straw (.P<0.05). CP a-part content of rapid degradation of ammonia treated rice straw was32.50%, which was higher than the the other groups (P<0.05), ED-value of ammonia treated rice straw was the highest, followed by rice straw silage, alkali treated rice straw and dry rice straw. NDF a-part content of rapid degradation of rice straw silage was significantly higher than those in other three rice straw (P<0.05), b-part content of slow degradation and ED-value effective degradation rate of alkali treated rice straw were significantly higher than rice straw silage and dry rice straw (P<0.05). NFC a-part content of rapid degradation of rice straw silage was significantly higher than those in other three rice straw (.P<0.05), ED-value of alkali treated rice straw was the highest, followed by rice straw silage, ammonia treated rice straw and dry rice straw. EDn/EDom and EDN/EDCHO of ammonia treated rice straw was the highest, followed by rice straw silage.Experiment2The effect of different treated rice straws on rumen fermentation pattern and micro floraAll the different treatment methods could significantly increase the gas production (P<0.05), The gas production of alkali treated rice straw was the highest. The methane production of alkali rice straw was the highest, followed by ammonia treated rice straw, rice straw silage and dry rice straw. Gas Demurrage time of rice straw silage was significantly lower than those in other three rice straw (P<0.05), dry rice straw, ammonia treated rice straw and alkali rice straw were not significant (P>0.05). Gas production rate of alkali treated rice straw was the fastest, dry rice straw, ammonia treated rice straw and alkali rice straw were not significant (P<0.05).The effects of rice straws on rumen fermentation. The concentration of ammonia nitrogen (NH3-N) of ammonia treated rice straw was significantly higher than those in other three rice straw (P<0.05). All the different treatment methods could significantly increased the total volatile fatty acid (TVFA) concentration (P<0.05), but had no significant effect on acetate and butyrate concentration (P>0.05). The rice straw silage and ammonia treated rice straw significantly increased rumen propionic concentration (P<0.05), but inhibited acetate to propionate ratio (P<0.05). The alkali treated rice straw had no significant effect on acetate, propionic and butyrate concentration (P>0.05).Different treated rice straws had significant effect on the percentage of total bacterial16SrDNA of Fibrobacter succinogenes, Methanogens. Compared with untreated rice straw, all treated rice straws had increased relative population of Fibrobacter succinogenes, and ammonia treated rice straw had decreased the population of methane bacteria. Different treatments had no significant impact on Ruminobacter albus, Ruminococcus flave faciens, Fungi and Protozo (P>0.05).It is concluded that different treated rice straw could improve nutrients, rumen degradation characteristics and rumen fermentation. Rice straw silage and ammoniation treated rice straw decrease the percentage of total bacterial16SrDNA of methane bacteria, and reduced methane/TVFA.