Study On Improving Feeding Value Of Palm Kernel Cake Using Microbial Fermentation Technology

The shortage of feed material is a major obstacle to the sustainable development of China’s breeding industry.Palm kernel cake is an important feed resource with rich nutrition,but its crude fiber content is more than 16% and its pungent smell limits its application in livestock and poultry diets.Therefore,it is necessary to scientifically treat palm kernel cake in order to reduce its crude fiber content,improve its flavor,and expand its application and usage in livestock and poultry breeding.In this paper,the utilization of microbial fermentation technology to improve the feeding value of palm kernel cake was studied by microbial screening,in degradation evaluation and broiler feeding experiment.The paper contains three experiments,and the results are as follows:(1)Experiment 1: Screening cellulose-degrading bacteriaIn this experiment,four cellulose degrading strains were screened from termites using carboxymethyl cellulose sodium selective medium,and 4 strains of bacteria were identified as Cellulosimicrobium cellulans strain,Bacillus wiedmannii,Bacillus safensis and Bacillus altitudinis,by morphological identification,Gram staining and molecular identification.The enzyme activities of filter paper were 0.150 U/m L,0.122 U/m L,0.165U/m L,0.203 U/m L,respectively;There was no antagonism among the isolates,and the degradation rate of crude fiber of palm kernel cake was 24.19% when 1:1:1:1 was used for fermentation.(2)Experiment 2: The fermentation effect of cellulose degrading bacteria on palm kernel cake.The experiment by comparing the different moisture content,fermentation time,fermentation temperature,fermentation,microbial inoculation amount,the substrate sterilization effect of cellulose degradation,further optimize the fermentation parameters,optimal fermentation conditions for compound strains to add 8%,the ratio of material to water while 45,36 ℃ fermentation temperature,fermentation time 4 d,the substrate without sterilization.Under the optimum fermentation parameters,the crude fiber decreased by 26.33%,crude protein increased by 25.45%,total acid increased by498.44%,acid soluble protein increased by 253.86%,total amino acid increased by 7.76%,and the flavor of palm meal was significantly improved by using compound bacteria.(3)Experiment 3: Application of fermented palm kernel cake in broiler feedBroilers were fed with fermented palm kernel cake prepared by the method of experiment 2 and corn-soybean meal basal diet as control.According to the principle of equal energy and equal protein,5% and 10% palm palm meal or fermented palm meal were added into the diet,respectively.150 one-day-old AA broilers were randomly divided into 5 groups with 6 replicates per group and 5 broilers per replicate.Group 1 was fed corn-soybean meal basal diet,groups 2 and 3 were fed 5% palm kernel cake and 5%fermented palm kernel cake diet,and groups 4 and 5 were fed 10% palm kernel cake and10% fermented palm kernel cake diet,respectively.The experiment lasted for 42 days.The results showed that palm meal fermentation significantly improved the performance of broilers(p<0.05),increased the apparent utilization rates of protein,calcium,phosphorus and ash,and increased the supplemental level(p<0.05),the optimal supplemental level was 10%,and the flavor was significantly improved.Compared with basal diet group,adding 10% fermented palm meal significantly improved meat quality(p<0.05),increased cecal microbial diversity(p<0.05),and had no adverse effects on body length,viscera index,intestinal relative length and weight,serum biochemical indices and blood routine of broilers.In conclusion,termites can be used as raw materials to screen out bacteria with high cellulose degradation efficiency,and compound bacteria can be added to palm meal for solid state fermentation,which can effectively degrade the cellulose content in palm meal and improve the nutritional value of palm meal.The application of fermented palm meal to broiler can obviously improve the growth performance of broiler and increase the proportion of additives.