| Xinjiang is livestock region. According to statistics, there is more than 1300 tons of forage shortfall currently in the region. A shortage of forage, imbalance in livestock has become a bottle neck restricting effect for the development of animal husbandry in Xinjiang. Cotton planting area in xinjiang accounts for about a third of the country,this area is rich in cotton stalk resources. Nutrients contained in cotton stalk is high-quality roughage basis, but the high fiber content of cotton stalks, poor palatability and feeding, high cost of harvesting and crushing have been a serious impediment to its effective use. It would have been excellent feeds for animal if the cellulose of cotton stalk can be degraded. The crucial strategy is to reduce the cellulose of cotton stalk. There are many bacteria, fungi, actinomycetes can degrade cellulose. In this study, High cellulase activity facultative anaerobes were isolated,and their application in fermented cotton stalks feed were studied. The main results are as follows:1. 44 strains were isolated from ruminant rumen fluid, feces, soil of different samples, the strains produce transparent circle on the cellulose congo red agar plate;After purification, the 24 strains were selected for bigger transparent circle,determinate the transparent circles diameter, as results, the ratio(D/d) between the transparent circle diameter(D) and colony diameter(d) has the maximum value 6.20.Through the determination of filter paper enzyme activity(FPA) and carboxymethyl enzyme activity(CMC), strain 22 has the highest enzyme activity, respectively9.697 UI and 10.326 UI.2. Cellulose degradation ability of strain 22 was subjected to rescreening optimize growth conditions to determine the optimal growing temperature and pH of bacteria. Strain 22 growing temperature ranges from 25~37℃, pH 5.0~8.0; The temperature without that range will restrain the growth of bacteria. The strain 22 with Cu-3, WS-6 and LP-2 have tested the antagonism, results show that there are no anyadverse reaction to inhibit each other between that 4 strains. By inoculation of 10%for the total amount of inoculation, the enzyme activity was mixed ratio of mixed bacteria indicators to determine the final test, to determine the optimum mixture ratio of the four kinds of bacteria was WS-6:LP-2:Cu-3:22=1:2:1:1. In addition, in the circumstance of inoculation amount equal to that of cellulose, the single bacteria’s enzyme activity is lower than any group of mixed strains of enzyme activity, therefore the enzyme producing ability of mixture was better than single bacterium.3. By the proportion of WS-6:LP-2:Cu-3:22=1:2:1:1, different level weight,moisture content and fermentation time as variable factors, micro storage were detected the index of sensory evaluation such as fermentation, the color, odor and feed structure, results showed that experimental group3 and 8 are fine feed, the rest of experimental groups are superior to feed; pH results showed that the highest pH value accounts for the control group is 8.7, the rest of the test group were lower than control group, the pH value within 4.24 ~ 5.99; Determination of dry matter content,according to the results of the control group of gaining the lowest content of dry matter(DM) was 2.2%, the rest of the group DM content increased by 5.1% ~ 5.1%;Feed of neutral detergent fiber(NDF), acid detergent fiber(ADF), hemi cellulose(HC)and Cellulose(Cellulose) content was lower than control group. The NDF content compared with the control group was reduced by 7.30% ~ 7.30%; ADF content was reduced by 4.96% ~ 4.96%; HC content was reduced by 2.34% ~ 2.34%; Cellulose content than the control group was reduced by 3.37% ~ 12.36%. The lowest cellulose content group is test group 11, by weight of mixed bacteria amount of 15%,fermentation time 25 d, moisture content 80%. |
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