饲养模式对坝上长尾鸡免疫水平及盲肠菌群的影响

Effects of feeding mode on cecum flora and immune level in Bashang long-tail chicken

为了探讨养殖模式对坝上长尾鸡免疫水平和盲肠菌群的影响,试验选择在笼养、舍内散养、草地放养、林地放养和山地放养5种养殖模式下饲养的坝上长尾鸡,分别在70,100日龄时采集试验鸡血液,采用红细胞凝集试验(HA)和血凝抑制试验(HI)测定新城疫抗体效价;屠宰试验鸡并称量肝脏、脾脏、胸腺、法氏囊重,计算免疫器官指数;取盲肠内容物,测定大肠杆菌、乳酸杆菌、双歧杆菌数量。结果表明:山地放养和林地放养模式新城疫HI抗体效价较高,各养殖模式下抗体水平随着日龄增大而降低。70,100日龄肝脏指数笼养模式极显著高于林地放养和山地放养(P<0.01),70日龄脾脏、胸腺、法氏囊指数山地放养>林地放养>草地放养>舍内散养>笼养,其中笼养和舍内散养模式肝脏指数与林地放养和山地放养模式比较差异极显著(P<0.01);100日龄法氏囊指数各组间差异不显著(P>0.05)。70,100日龄坝上长尾鸡盲肠大肠杆菌数量舍内散养>笼养>草地放养>林地放养>山地放养,双歧杆菌和乳酸杆菌数量山地放养>林地放养>草地放养>舍内散养>笼养。说明养殖模式影响新城疫抗体效价、机体免疫力和肠道微生物菌群数量,山地放养和林地放养模式更有利于提高坝上长尾鸡的免疫力和抗病力。

In order to explore the effect of breeding mode on immune level and cecal flora of Bashang long-tailed chickens,Bashang long-tailed chickens reared in five breeding modes were selected in this experiment,including cage rearing,house free-range rearing,grass rearing,woodland rearing and mountain rearing. Blood was collected from test chickens at 70 and 100 days of age,and hemagglutination test(HA) and hemagglutination inhibition test(HI) were used to determine Newcastle disease antibody titers. The test chickens were slaughtered,and the liver,spleen,thymus and bursa of fabricius were weighed,and the immune organ indexes were calculated. The contents of the cecum were taked to determine the number of Escherichia coli,Lactobacillus,and Bifidobacterium. The results showed that the titers of Newcastle disease antibody(HI) were higher in woodland rearing and mountain rearing,and the antibody levels were decreased with the increase of age in each culture mode. 70,100-day-old liver indexes in cage rearing were significantly higher than those in woodland rearing and mountain rearing(P<0.01);70-day-old spleen,thymus and bursa of fabricius indexes were higher in mountain rearing>woodland rearing>grassland rearing>house free-range rearing>cage rearing. The difference of liver index between cage rearing/house free-range rearing and grass rearing/woodland rearing was significant(P<0.01);there was no significant difference in 100-day-old bursa of fabricius indexes between the groups(P>0.05). The numbers of caecal E. coli in Bashang long-tailed chickens at 70,100 days old were higher in house free-range rearing>cage rearing>grassland rearing>woodland rearing>mountain rearing;the numbers of Lactobacillus and Bifidobacterium were higher in mountain rearing>woodland rearing>grassland rearing>house free-range rearing>cage rearing. The results suggested that the breeding mode affected the antibody titer of Newcastle disease,the immunity of the organism and the number of intestinal microflora. The modes of mountain rearing and woodland rearing are more beneficial to improve the immunity and disease resistance of Bashang long-tailed chicken.