Effects of Compound Probiotic Preparation on Performance,Egg Quality,Serum Indexes,Nutrient Apparent Metabolic Rates and Fecal Pollutant Emissions of Laying Hens
The purpose of this experiment was to investigate the effects of compound probiotic preparation on the performance,egg quality,serum indexes,nutrient apparent metabolic rates and fecal pollutant emissions of laying hens,and to provide experimental basis for the application of compound probiotic preparation in layer production.A total of 288 fifty-weeek-old Jinghong laying hens with similar egg production rate and health were randomly selected and divided into four groups,with six replicates for each group and 12 hens for each replicate.Laying hens in control group were fed a corn-soybean meal type basal diet,and those in experimental groups were fed the control group's diet supplemented with 100,150 and 200 mg/kg of compound probiotic preparation(It consisted of Bacillus subtilis,Bacillus licheniformis,Clostridium butyricum and Enterococcus faecalis),respectively.The pre-feeding period was 7 d,and the formal test period was 84 d.The results showed as follows:1)the laying rate of the 150 mg/kg group was significantly higher than that of the control group(P＜0.05);the broken egg rate of the 200 mg/kg group was significantly lower than that of the control group(P＜0.05),but the difference between the 150 and 200 mg/kg groups was insignificant(P＞0.05).2)The eggshell thickness of the 200 mg/kg group was significantly higher than that of the control group(P＜0.05),and there was no significant difference between the 200 and 150 mg/kg groups(P＞0.05).3)Serum albumin content of the 150 mg/kg group was significantly higher than that of the other group(P＜0.05);ser-um urea nitrogen content of the 200 mg/kg group was significantly lower than that of the control group(P＜0.05),and there was no significant difference with that in the 150 mg/kg group(P＞0.05).4)Crude protein apparent metabolic rate of the 200 mg/kg group was significantly higher than that of the control group and 100 mg/kg group(P＜0.05),but not significantly different from that of the 150 mg/kg group(P＞0.05);calcium apparent metabolic rate of the 150 and 200 mg/kg groups was significantly higher than of the control group and 100 mg/kg group(P＜0.05),but there was no significant difference between the 150 and 200 mg/kg groups(P＞0.05).5)The indole and 3-methylindole contents and ammonia emission in the feces of 150 and 200 mg/kg groups was significantly lower than those of the control group and 100 mg/kg group(P＜0.05),and there was no significant difference between the 150 and 200 mg/kg groups(P＞0.05).6)The villus height of the duodenum of the 200 mg/kg group was significantly higher than that of the control group and 100 mg/kg group(P＜0.05),and there was no significant difference between the 150 and 200 mg/kg groups(P＞0.05).7)The highest average profit per hen was recorded in the 150 mg/kg group,which was 7.40％higher than that of the control group.In conclusion,it is recommended that the additive a-mount of compound probiotic preparation in the diet of laying hens should be 150 mg/kg.[Chinese Journal of Animal Nutrition,2024,36(12):7687-7697]
万方数据
维普
