Study On Microbial Fermentation Protein Supplement

Soybean meal,cotton meal and other plant-derived protein feeds are widely used in production,but they are difficult to be digested and absorpted due to containing many anti-nutritional factors,such as trypsin inhibitor,free phenol and so on.Microbial fermentation can not only improve the quality of meal raw materials,but also effectively improve the utilization rate of some low-quality agricultural by-products.In this study,8 solid-state fermentation formulas were designed by using 9 ingredients,such as cottonseed meal,corn germ meal,soybean meal,jujube powder and inorganic salt,as raw materials.The solid-state fermentation conditions include factors like high stockpiling material,initial water content,turning temperature and fermentation time.The pH value of fermentation material,yeast viablecounts,as well as contents of?-glucan,mannan,organic acid and polypeptide were determined.Based on that,the optimum composition and fermentation conditions of microbial fermentation protein supplement were selected.Meanwhile,the effects of microbial fermentation protein supplement on rumen fermentation parameters and dry matter digestibility were studied using in vitro method,and the optimum supplement amount was determined at 6:4 and 7:3 diets.The experimental results showed that:1.The optimum formula of microbial fermentation protein supplement was:jujube powder 12.1%,cottonseed meal 28.3%,corn germ meal 10.0%,corn husk 11.2%,soybean meal 32.2%,bran 3.6%,ammonium sulfate 2.0%,potassium dihydrogen phosphate 0.50%and magnesium sulfate 0.10%.2.The optimum fermentation process of microbial fermentation protein supplement was determined as follows:solid-state material accumulation high 30 cm,initial water content 47.3%,turning temperature 45 ?,and fermentation time 48 h.3.In vitro,the optimum amount of microbial fermentation protein supplement was 17.24%at 6:4 diet and 6.64%at 7:3 diet.Microbial fermentation protein supplement could significantly increase gas production ofmedium,dry matter digestibility and bacterial protein content(P<0.05)andmarkedly reduce ammonia nitrogen concentration inthemedium(P<0.05),but had no significant effect on pH value(P>0.05).