Studies on Bio-detoxification of Cottonseed Meal and Its Application in Broiler Diets
|School||Chinese Academy of Agricultural Sciences|
|Course||Animal Nutrition and Feed Science|
|Keywords||Gossypol Solid-state fermentation Process optimization Response surface analysis Fermented cottonseed meal Broilers Production performance Gut microbes|
This thesis through microbial fermentation test screening effective microbial degradation of harmful ingredients free gossypol in cottonseed meal (Free Gossypol, FG) strains, and optimize the microbial detoxification cottonseed meal optimal fermentation conditions, results show that material to water ratio of 1:0.94, the fermentation time 62.33h loading capacity 30.96g/150mL, inoculum 10%, bran amount of 20% of virus-free rate (nearly 86%); subsequent fermentation of cottonseed meal in broilers. pilot study results show that, compared with the control group, fermented cottonseed meal did not have a significant impact on broiler performance, meat quality and immune organ index and apparent energy and protein metabolism, when the dosage 20% of intestinal lactic acid bacteria significantly increased (P lt; 0.05), and E. coli was significantly lower (P lt; 0.05), and the most cost savings. Therefore, fermentation detoxification cottonseed meal added in an amount of 20%. Test a fermentation bacteria screening test for screening microbial strains to efficiently degrade gossypol. First Geotrichum candidum buckle sac, Candida tropicalis, Candida utilis yeast, of 3 Aspergillus niger and two meters Aspergillus strains candidate strains, the use of non-carbon source liquid medium each 30ml plus cottonseed meal 2g liquid fermentation, 25 to 28 ° C, 250 r / min Shaker 48h after to remove microbial fermentation liquid determination of free gossypol content utilis yeast gossypol degradation rate of about 70% in other species no significant effect; then using Candida utilis solid-state fermentation of cottonseed meal and wheat bran mixture, 150 ml of flask filling 30g, 28 ℃ for cultured 48h, once every 12h stirring after 48 hours to remove fermentation product bake dry, crushed, Determination of gossypol content. The results show that, utilis yeast solid-state fermentation of cottonseed meal detoxification rate between 65% to 70%. This indicates utilis yeast has an effective role in degradation of gossypol. Test the cottonseed meal fermentation process conditions optimization of this test optimized utilis yeast degradation of free gossypol in cottonseed meal optimal parameters. Solid-state fermentation First Plackett-Burman design using SAS software utilis yeast fermentation parameters of cottonseed meal were screened, draw greater impact three important factors, namely: the ratio of water, fermentation time and loading capacity , then the SAS software secondary response surface analysis, regression analysis, and to get the best value of the various factors. The results show that the ratio of water to 1:0.94, fermentation time 62.33h loading capacity when 30.96g/150mL detoxification highest rate (85.99%), and optimization increased by nearly 20% compared to before; then based on the response surface optimization The bran and vaccination amount a single factor optimization. The results showed that the inoculum 10%, bran amount of virus-free rate of 20% relative maximum. The cottonseed meal fermented crude protein content did not change, the content of soluble protein increased from 6.96% to 10.2%, essential amino acids - lysine, threonine, leucine, isoleucine, leucine, increased. Optimization of the fermentation parameters, cottonseed meal detoxification rate increased and improved the nutritional value of cottonseed meal after fermentation. Test fermented cottonseed meal on broiler performance and related indicators of this test to explore the fermentation of cottonseed meal on broiler performance, meat quality and immune organ index and protein energy metabolism. Selection of 192 one-day-old AA broilers were randomly divided into four treatment groups, six replicates per treatment, each repeated eight chickens, the control group was fed corn-soybean meal basal diet treatment group 1-3 were added fermented cottonseed meal 15%, 20% and 30% partial replacement of soybean meal. Test period of six weeks. The test results show that the fermentation of cottonseed meal treated broiler performance, meat quality and immune organ index and apparent protein metabolism value of the control group compared to the failed significant difference (p gt; 0.05). Considering the economic costs that fermented cottonseed meal added in an amount of 20%. Test fermented cottonseed meal on cecal microbial flora of this test using traditional microbiological culture and PCR-DGGE method to study the fermentation of cottonseed meal of of broiler cecal several major number of microorganisms and fauna. Selection of 192 one-day-old AA broilers were randomly divided into four treatment groups, six replicates per treatment, each repeated eight chickens, the control group was fed corn-soybean meal basal diet treatment group 1-3 were added fermented cottonseed meal 15%, 20% and 30% partial replacement of soybean meal. Test period of six weeks. Test the last day were randomly selected from each repeat a broiler slaughter sterile collection the cecal chyme analysis cecal microbial quantity and flora. The results show that, when fermented cottonseed meal dosage by 15% and 20%, the number of cecal lactobacilli significant increase (P lt; 0.05), a significant reduction in the number of E. coli (P lt; 0.05) increase in the number of bifidobacteria but did not reach a significant level (P gt; 0.05); PCR-DGGE profiles showed that intestinal feeding cottonseed meal after fermentation, a slight change in the structure of microbial populations, fermentation of cottonseed meal increased microbial population, the type of microbial populations in each treatment group both similarities and there are differences, but there was a significant difference. The tests showed that the fermentation of cottonseed meal adjustable the broiler intestinal micro ecological balance, especially the increase in the number of Lactobacillus and E. coli reduce the number of beneficial bacteria.