虾青素和抗菌肽联合对产蛋后期蛋鸡免疫功能、肠道形态和盲肠微生物数量的影响

Effects of combined astaxanthin and antimicrobial peptides on immune function,intestinal morphology and cecum microbial population of laying hens in the late laying period

为研究日粮中添加虾青素和抗菌肽对产蛋后期蛋鸡免疫功能、肠道形态和盲肠微生物数量的影响,选取健康且体重相近的56周龄海兰褐蛋鸡700只,随机分为7个组,每组5个重复,每个重复20只。E_(0)为对照组,饲喂基础日粮;E1~E6为试验组,各组单独饲喂添加不同水平的虾青素(0.5%、1.0%、1.5%)和抗菌肽(300、500 mg/kg)。预饲期1周,正饲期8周。试验结束采血测定免疫指标及肠道形态和盲肠微生物数量。结果表明:(1)免疫功能:试验组E_(1)~E_(6)的IgG、IgM、IL-2、IL-10、IFN-和IFN-均显著高于对照组E0(P<0.05)。(2)肠道形态:在空肠中,试验组E3的绒毛高度显著高于对照组E0(P<0.05),试验组E_(1)~E_(6)的隐窝深度和绒隐比与对照组E0相比有显著差异(P<0.05)。在回肠中,试验组E_(1)~E_(6)的绒毛高度、隐窝深度和绒隐比与对照组E_(0)相比均有显著差异(P<0.05)。(3)盲肠微生物数量:试验组E_(1)~E_(6)的乳酸杆菌数量与大肠杆菌数量与对照组E_(0)相比有显著差异(P<0.05)。整个试验期E3组各项测试指标均最优。综上所述,饲粮中添加虾青素和抗菌肽可增强蛋鸡的免疫功能,改善空肠和回肠形态结构,且以添加1.0%虾青素和300 mg/kg抗菌肽效果较佳。

The experiment aimed to investigate the effects of astaxanthin and antimicrobial peptides on the immune function,intestinal morphology and cecal microbial population of laying hens in the late laying period.Select 700 healthy and similar weight 56 week old Hailan brown laying hens and randomly divide them into 7 groups with 5 replicates and 20 each.E_(0) was the control group,fed basal diet;E_(1)~E_(6) was experimental group,with each group fed separately with different levels of astaxanthin(0.5%,1.0%,1.5%)and antimicrobial peptides(300,500 mg/kg).The pre-test period was 1 week and the trial period was 8 weeks.At the end of the experiment,blood was collected to measure immune indicators,intestinal morphology and cecal microbiota.The results showed that:(1)Immune function:the IgG,IgM,IL-2,IL-10,IFN-(and IFN-(of the test group E_(1)~E_(6) were significantly higher than those of the control group E_(0)(P<0.05).(2)Intestinal morphology:in the jejunum,the villus height of test group E_(3) was significantly higher than that of control group E0(P<0.05),and the crypt depths and villus crypt ratios of test groups E_(1)~E_(6) were significantly different compared with those of control group E_(0)(P<0.05).In the ileum,the villus height,crypt depth and villous crypt ratio of the test group E_(1)~E_(6) were significantly different compared with the control group E_(0)(P<0.05).(3)The number of cecal microbiota:there was a significant difference between the number of Lactobacillus and E.coli in the test group E_(1)~E_(6) compared with the control group E0(P<0.05).The group E3 was optimized in every test index throughout the test period.In summary,adding astaxanthin and antimicrobial peptides to the diet could enhance the immune function of laying hens,improve the morphological structure of the jejunum and ileum,and the best effect was 1.0% astaxanthin and 300 mg/kg antimicrobial peptides added in basel diet.