Optimization Of Citrus Pomace Fermentation Process And Its Effect On Growth Performance And Meat Quality Of Yellow-Feathered Chickens

Citrus pomace is a by-product of citrus processing.Because it is rich in pectin,orange peel essential oils,pigments,and dietary fiber and other functional ingredients,it has high nutritional value and rich resources,and can be developed and used as an unconventional feed resource.Therefore,this experiment used citrus pomace fermentation to produce protein feed,studied the optimal process conditions of citrus pomace fermentation,and evaluated the feeding value of fermented citrus pomace through the feeding experiment of broilers.The test is divided into three parts:Experiment 1:Study the best fermentation process conditions of citrus pomace.In this experiment,citrus pomace was taken as the research object,and strains suitable for fermentation were selected.In the form of mixed fermentation,the amount of urea added was screened,and based on previous research,orthogonal analysis was carried out on the proportion of fermentation substrate,inoculum amount of bacterial liquid,and fermentation time to optimize the fermentation process conditions of citrus pomace.The optimal process conditions for citrus pomace fermentation are inoculation ratio 1:1:1:1,urea addition amount 1.5%,fermentation substrate citrus pomace and bran ratio 7:3,inoculation amount 15%,fermentation time 4 d,water content 60%,Temperature 30℃.Experiment 2:Study the effects of fermented citrus pomace on growth performance,nutrient apparent digestibility,blood biochemical indexes and intestinal morphology.A total of 540 healthy 90-day-old Qingyuan patride hens were randomLy divided into three treatment groups according to body weight,namely control group,10%dry citrus pomace group and 10%fermented citrus pomace group.Each group has 6 repetitions,and each repetition has 30 animals.The test period is 30 days.The results show:(1)The addition of fermented citrus pomace to the diet significantly increased the Final BW and ADG(P<0.05),and the F/G tended to increase(P>0.05,P<0.1).(2)The addition of fermented citrus pomace to the diet has no adverse effect on the immune organ index of broilers(P>0.05).(3)The addition of fermented citrus pomace to the diet has a tendency to increase the CP digestibility of broilers(P>0.05,P<0.1).(4)The addition of fermented citrus pomace to the diet significantly increased the glucose content in broiler blood(P<0.0.5),significantly reduced the content of urea and cholesterol(P<0.0.5),and significantly reduced the activity of aspartate aminotransferase(P<0.05).(5)The addition of fermented citrus pomace to the diet significantly increased the height of the jejunum villi(P<0.05),and significantly reduced the depth of the ileum crypt(P<0.05).Experiment 3:Study the effect of fermented citrus pomace on slaughter performance,meat quality and fatty acid composition of broilers.The design of the experiment is the same as that of Experiment 1.The results are as follows:(1)The addition of fermented citrus pomace to the diet has no adverse effect on the slaughter performance of broiler(P<0.05).(2)The addition of fermented citrus pomace to the diet significantly increased the pH value of muscle 45 minutes after broiler slaughter,the yellowness value of meat color at 24 h,and the content of inosinic acid(P<0.05).(3)The addition of fermented citrus pomace to the diet significantly increased the content of polyunsaturated fatty acids in broilers(P<0.05).The above results show that the addition of fermented citrus pomace in the diet can significantly improve the growth performance of broilers,regulate the body’s metabolic level,improve intestinal morphology,and improve meat quality.