The Dynamics And Mechanism Of Micro-organisms In Fermented Bed For Dairy Cattle Breeding, And Its Impact On Production Performance Of Dairy Cow

To solve the manure pollution problem in breeding industry of dairy cows, we selected high activity enzymatic strains with stable growth characteristic based on the basic principals in deep-litter system technology and the behavioral habits of cows.We further applied these high activity enzymatic strains to the deep-litter system technology for dairy cattle breeding, in order to improve the condition in cow pens, increase the productivity and quality of milk.First, this study specifically selected three high enzymatic activity strains from large number of samples based on the characteristics of manure from cows:high volume and rich in cellulose. Two of these strains are identified as bacillus and one as yeast. After repeated fermentation, these three strains were proved to have stable enzymatic activity and excellent growth performance.Then, after pH value, ammonium nitrogen and nitrate nitrogen, and every enzymatic activity test, we investigated the mechanism of how microorganism participates fermentation process. The result shows that:1. The experimental group's surface is almost odorless with low humidity. Ferment process has first increased the internal temperature and decreased afterwards. The decreased pH value in the system reduces the evaporation of NH3. In contrast, the odor from the specimen of the control group attracts more flies. The padding turned dark and humid, tending to be rotten. During the whole process, the temperature remains the same level as the room temperature and pH value is always higher than that of experimental group.2. Fermentation process accelerated degradation of organics to ammonium nitrogen, enhanced the capability of nitrification, lowered the pH value in the specimen, reduced nitrate nitrogen, and increased the denitrification capacity of padding.3. The enzymatic activity of cellulose, protease and urease are enhanced, which accelerates the metabolism process of the system, thusly plays a crucial role in efficient and effective processing of manure.In the end, we implemented deep-litter system technology by carefully starting animal control test and periodically recording the temperature change in the fermentation process of 1 itter. We also detected the variation in the quantity variation of probiotics and harmful bacteria. The adoption of PCR-DGGE technique enables us to monitor the microbial dynamics in different stages of the bedding course. In the meanwhile, we supplemented microorganism in the dairy cow diet, coupled with deep-litter system technology, to study its influence on the milk production, quality of milk and intestinal flora. The study of animal experiment shows that:1. In the fermentation process, most microorganisms appear to be decreasing in volume, yet with different trends. Probiotics almost remain the same level with slight decrease following an increase in the end, and remain higher level than the control group. Harmful bacteria decrease dramatically in volume and lower than the controls group, with total elimination of some bacterium. DGGE DNA profiles show that the variety of microorganism is decreased and the stability is therefore enhanced:the average number of strap decreased from 38.7 to 29.2. The average milk production per day decreased by 0.36kg per cattle in control group, with insignificant difference (P>0.05). In contrast, the cows bred with micro-ecological preparations, in the same environment have increased 1.81kg in average milk production per day, comparing to control group with extremely significant difference (P<0.01). In the dairy product, protein has increased by 0.04%(P>0.05), lactose by 0.03%(P>0.05); SNF by 0.05%(P>0.05); fat decreased by 0.46%, with significant difference (P<0.05).3. We observed from DGGE DNA profiles that the control group has a greater variety of microorganism than that of experimental group:the average straps are 27.6 in control experimental group comparing to 23.6 in group experimental group with significant difference. Meanwhile, the similarity between specimens in experimental group is comparatively higher, with high 97% and low 87%, where this index between specimens in control group lies in the range of 91% to 77%, indicating a significant difference between individual specimens in the control group. These results confirmed that the variety of intestinal flora in dairy cows is significantly improved and the variation between individual cows is largely decreased by supplementing micro-ecological preparations in the diet, coupled with deep-litter system technology, which promote the colonization of microorganism in intestinal and improves the stability of flora.