Effects Of Alfalfa Crude Polysaccharides On Performance,Egg Quality And Intestinal Microecology Of Laying Hens

This experiment was conducted to study the effects of dietary supplementation with alfalfa crude polysaccharides(ACPS)at different levels on production performance,egg quality,gastrointestinal p H and caecal microflora numbers of laying hens.We wanted to estimate the effectiveness of ACPS and its effects on the intestinal health of laying hens,also provide experimental evidence for the exploitation and application of ACPS.A total of five hundred and forty aged 30-week-old Hy-line Brown hens were randomly allocated to 6 groups with 6 replicates per group and 15 hens per replicate.Group 1 was control group,fed with the corn-soybean meal basal diet.And those in testing groups were fed the basal diet supplemented ACPS at 250?500?1 000?2 000 and 4 000 mg/kg,respectively.The preliminary trial period lasted 14 days,the formal experiment lasted 144 days.The results showed as follows:1.Effects of dietary supplementation with alfalfa crude polysaccharides on production performance and egg quality of laying hens1)during week 1 to 8,the laying rate of 2 000 and 4 000 mg/kg groups was significantly higher than that of the control and 250 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 250mg/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 ACSP 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 significantly decreased the egg shape index on days 60(P<0.05),and 1 000 mg/kg ACPS group also significantly decreased the egg shape index on day 120(P<0.05).The 250 and 1 000mg/kg ACPS groups significantly decreased the soft shelled or cracked eggs rate during day 61 to 90(P<0.05).These data suggest that the suitable amount of ACPS can enhance production performance and improve egg quality of laying hens.2.Effects of dietary supplementation with alfalfa crude polsaccharides on gastrointestinal p H and caecal microflora numbers of laying hens1)Compared with the control group,the 500 mg/kg ACPS group decreased the p H of muscular and glandular stomach content,but differences between them were not significant(P>0.05),the 250 mg/kg ACPS group significantly increased the p H of jejunum content(P<0.05),the 500 mg/kg ACPS group significantly decreased the p H of caecal content(P<0.05).2)Compared with the control group,the 500 and 2 000 ACPS 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 days 80(P<0.05);the 1 000 mg/kg ACPS group significantly decreased the number of Salmonella on day 144(P<0.05);the 500 and 1 000 mg/kg ACPS groups increased the number of Bifidobacterium in cecumon day 40,80,120 and 144,but differences between them were not significant(P>0.05).These data suggest that dietary supplemented suitable level of ACPS can significantly decreased the gastrointestinal p H,stimulate the growth of beneficial bacterium in intestinal tract,while inhibit the growth of harmful bacterium in intestinal tract,and improve the intestinal microecology.