The Preparation Of Small Peptides From Feed Protein Source And Its Impact On Cows Lactation

Nowadays, the number of cows is about 14 million in China, and annual production capacity is about 34 million tons, annual growth rate between keeping the volume of cows and milk yield has been approximately 10%~15%,the shortage gap of protein feed resources is gradually increasing, A well-established channels is developed that change the current issue is to yield one products which has a role of biological activity and high feed use efficiency; At present, the average yield of dairy cows in China is only 4100 kg/year, and lactoprotein content is 2.95%~3.0%, but the average yield of dairy cows in the world is about 5500 kg/year, and lactoprotein content is 3.2%~4.0%, even in US, the average yield of dairy cows is more 8879 Kg/year, and lactoprotein content is 3.20%~3.6%. and so, the row yield of dairy cows become the most problem that constrains the development of our country's dairy industry, to improve cows'milk production from the point of nutrition is an active method to solve the problem.Small peptide as nutrition additives have been used in dairy production, but the most of small peptides is crude products that single protein feed resource have been made by enzymatic method or by microbial fermentation, and of course, and its also has been made for complement of protein nutrition, currently, adopt mixed lactic acid bacteria fermentation plus enzymatic method to yield the small peptides of products is still not reported, with its biological activity to increase feed use efficiency, improve milk yield and quality. The aim of this study is to prepare a small peptides, in the process of selecting of raw materials, by way of select soybean meal,corn gluten meal and bran and full account of its that are mixed lysine and methionine's content, use lactobacillus bulgaricus,lactococcus lactis strain which have protease activity to ferment, improve the protein,lysine and methionine content, at last, by trypsin,pancreatin to mixed enzyme, to gain lower peptide chain length, increase the role of biological activity.The research results are as follows:This study has researched and analyzed the production process of small peptides that have been prepared by lactic acid bacteria fermentation and enzymatic hydrolization, this process has a high feasible, higher small peptides'yield, TCA-NSI is 65%, average peptide chain length is 3.44, methinion content is 2.51%, raised 1.67% (compared with the rough material );lysine content is 5.17%, raised 1.76%(compared with the rough material ). HPLC method has been set up in this experiment.Small peptides products of feed protein source produced in this experiment is added to dairy's feed supplement. Test group are randomly divided into three groups (the amount of adding small peptides productions is respectively according to the ration's 0.1%, 0.3%, 0.6%), the results are: the milk production of test groups in trial period are significantly more than test groups in former trial period(P<0.01), increasing: 2.0%, 6.1%, 7.4% respectively; Milk fat percentage and milk protein content were all clear increasing, the test groups'milk fat percentage increasing: 0.8%, 2.1%, 2.9% respectively, the test groups'milk protein contents percentage increasing: 1.4%, 1.7%, 2.0% respectively, the changes in the lactose and dry matter content have also obvious increasing; Furthermore, the analysis of actual product's economic benefits shows that the group of 0.3% is the best compared with the other two groups. The results show that small peptides products can increase milk production and improve milk quality.