紫花苜蓿粗多糖对蛋鸡生产性能、蛋品质及盲肠微生物数量的影响

本试验旨在研究饲粮中添加不同水平紫花苜蓿粗多糖对蛋鸡生产性能、蛋品质及盲肠微生物数量的影响。选取540只30周龄的海兰褐壳蛋鸡,随机分为6组,每组6个重复,每个重复15只鸡。对照组饲喂玉米-豆粕型基础饲粮,试验组分别在基础饲粮中添加250、500、1 000、2 000、4 000 mg/kg紫花苜蓿粗多糖。试验期144 d。结果表明:1)试验第1~8周,2 000、4 000 mg/kg紫花苜蓿粗多糖组产蛋率显著高于对照组和250 mg/kg紫花苜蓿粗多糖组(P0.05);试验第17~20周,2 000 mg/kg紫花苜蓿粗多糖组平均日采食量显著高于对照组和250 mg/kg紫花苜蓿粗多糖组(P0.05),同时250 mg/kg紫花苜蓿粗多糖组料蛋比显著低于对照组和500 mg/kg紫花苜蓿粗多糖组(P0.05)。2)与对照组相比,试验第144天,各紫花苜蓿粗多糖组蛋黄颜色均显著加深(P0.05);试验第90天,4 000 mg/kg紫花苜蓿粗多糖组哈夫单位显著降低(P0.05);试验第60天,2 000、4 000 mg/kg紫花苜蓿粗多糖组蛋形指数显著降低(P0.05),试验第120天,1 000 mg/kg紫花苜蓿粗多糖组蛋形指数亦显著降低(P0.05);试验第61~90天,250、1 000 mg/kg紫花苜蓿粗多糖组软破壳蛋率显著降低(P0.05)。3)与对照组相比,试验第80天,500、2 000 mg/kg紫花苜蓿粗多糖组盲肠大肠杆菌数量显著降低(P0.05),盲肠乳酸杆菌数量显著增加(P0.05),同时4 000 mg/kg紫花苜蓿粗多糖组盲肠乳酸杆菌数量也显著增加(P0.05);试验第144天,1 000 mg/kg紫花苜蓿粗多糖组盲肠沙门氏菌数量显著降低(P0.05);试验第40、80、120、144天,500、1 000 mg/kg紫花苜蓿粗多糖组盲肠双歧杆菌数量均有所升高,但差异不显著(P0.05)。由此可见,饲粮中添加适宜水平的紫花苜蓿粗多糖可以显著提高产蛋期蛋鸡生产性能,改善蛋品质,优化盲肠菌群结构,且500 mg/kg为适宜添加水平。

Effects of Alfalfa Crude Polysaccharides on Performance,Egg Quality and Caecal Microflora Numbers of Laying Hens

This experiment was conducted to study the effects of dietary different supplemental levels of alfalfa crude polysaccharides (ACPS) on performance, egg quality and caecal microflora numbers of laying hens.Five hundred and forty 30-week-old Hy-line brown hens were randomly allocated to 6 groups with 6 replicates per group and 15 hens per replicate.Hens in control group were fed a corn-soybean meal basal diet, and those in testing groups were fed the basal diet supplemented with 250, 500, 1 000, 2 000 and 4 000 mg/kg ACPS,respectively.The experiment lasted for 144 days.The results showed as follows: 1) during week 1 to 8, the laying rate of 2 000 and 4 000 mg/kg ACPS groups was significantly higher than that of the control and250 mg/kg ACPS groups (P<0.05).During week 17 to 20, the average daily feed intake of 2 000 mg/kg ACPS group was significantly higher than that of the control and 250 mg/kg ACPS groups (P<0.05), while the feed to egg ratio of 250 mg/kg ACPS group was significantly lower than that of the control and 500 mg/kg ACPS groups (P<0.05).2) Compared with the control group, all ACPS groups significantly improved the egg yolk color on day 144 (P<0.05), the 4 000 mg/kg ACPS group significantly decreased the Haugh unit on day 90 (P<0.05), the 2 000 and 4 000 mg/kg ACPS groups significantly decreased the egg shape index on day 60 (P<0.05), the 1 000 mg/kg ACPS group also significantly decreased the egg shape index on day 120(P<0.05), the 250 and 1 000 mg/kg ACPS groups significantly decreased the soft shelled or cracked eggs rate during day 61 to 90 (P<0.05).3) Compared with the control group, the 500 and 2 000 ACPS groups significantly decreased the number of Escherichia coli in cecum on day 80, while the number of Lactobacillus in cecum was significantly increased on day 80 (P<0.05), and the 4 000 mg/kg ACPS group also significantly increased the number of Lactobacillus in cecum on day 80 (P<0.05);the 1 000 mg/kg ACPS group significantly decreased the number of Salmonella in cecum on day 144 (P<0.05);the 500 and 1 000 mg/kg ACPS groups increased the number of Bifidobacterium in caecum on day 40, 80, 120 and 144, but differences between them were not significant (P>0.05).In conclusion, dietary supplemented suitable level of ACPS can enhance performance of laying hens during laying period, improve egg quality, and optimize caecal microflora structure.The appropriate supplemental level of ACPS is 500 mg/kg.Chinese Journal of Animal Nutrition,