【作者】 聂新志；

【导师】 贺建华；

【作者基本信息】 湖南农业大学 ， 动物营养与饲料科学， 2004， 硕士

【摘要】 本试验研究了不同添加水平的益生素对艾维茵肉鸡生产性能、免疫机能及血液生化指标的影响。试验采用完全随机区组设计，分别在含黄霉素和不含黄霉素的日粮中添加不同水平的益生素（0、0.2％、0.4％、0.6％）。试验选用了3776羽体重基本一致的1日龄的艾维茵公雏，随机分成8组，每组6个重复，每个重复60只鸡。第1至4组分别在含黄霉素6 mg／kg的日粮中添加0、0.2％、0.4％、0.6％的益生素，第5至8组分别在不含黄霉素的日粮中添加0、0.2％、0.4％、0.6％的益生素。另外，每组再设一个消化组，每个消化组112只鸡，饲喂添加了0.3％Cr₂O₃指示剂的日粮。试验分为试验前期（0-21天）和后期（22-42天）。整个试验期实行24小时光照，自由采食和饮水。试验第21、40天时，测定肉鸡体重、采食量，计算料肉比。第14、40天时，从每组每重复分别随机抽取6只和3只鸡，翅静脉采血10ml，用于测定T细胞转化率及血清中IgG、IgA、TP、ALB、GLOB、TG、TC、Ca、P含量。第21、42天时，将每组用作消化试验的鸡解剖，分离脾脏、法氏囊和胸腺，切取盲肠扁桃体，取回肠内容物，用于测定免疫器官的变化及营养物质的消化率。 结果表明，（1） 在肉鸡日粮中添加益生素对前期增重、采食量和料肉比作用不显著（P＞0.05），对干物质（DM）、有机物（0M）、粗蛋白（CP）、钙（Ca）、磷（P）和部分必需氨基酸的消化率影响显著（P＜0.05）。添加0.2％益生素能显著提高肉鸡对DM、OM、CP、Ca、P和试验前期Met、Lys、Phe、Ile、His的消化率（P＜0.05）；添加0.4％益生素能显著提高试验后期肉鸡增重（P＜0.05），但会降低饲料利用率（P＞0.05）。（2） 试验前期，益生素能提高法氏囊、胸腺指数，增大盲肠扁桃体面积。添加量为0.2％时能极显著地增大盲肠扁桃体面积（P＜0.01），添加量为0.4％时能显著提高脾脏指数（P＜0.05），极显著提高法氏囊指数（P＜0.01）；试验后期，益生素不能促进肉鸡免疫器官生长。（3） 益生素对血清中IgG、IgA含量影响显著（P＜0.05），但对T细胞转化率无影响（P＞0.05）。其中，添加0.4％益生素能显著提高血清中IgG、IgA的含量（P＜0.05）。（4） 益生素能提高血清总蛋白、清蛋白和球蛋白含量和球／清蛋白比值。其中，添加0.2％益生素在试验前期，能显著提高血清球蛋白含量和G／A值（P＜0.05）；试验后期能极显著提高血清总蛋白、球蛋白含量（P＜0.01），显著提高球／清蛋白比值（P＜0.05）。（5） 益生素对血清中钙、磷含量影响显著，添加量为0.2%时在试验前期能极显著地提高血清中磷的含量甲<0 .01)，试验后期能显著增加血清中钙的含量（P<o.05）。（6）益生素能降低血清中总脂（TG）和TC含量，其中，添加0.2%益生素能显著降低血清中总脂含量和胆固醇水平（P<0 .05）。（7）单独添加益生素、黄霉素以及两者联合使用，作用效果差异不显著（P>0 .05）。 从上述结果可看出:1、在肉鸡日粮中添加益生素，能提高干物质、有机物、粗蛋白的消化率，促 进各种必需氨基酸的消化吸收。2、益生素能提高肉鸡免疫力。试验前期，能促进「细胞转化，显著提高法氏 囊指数和胸腺指数，极显著增大盲肠扁桃体面积。试验后期，益生素能极 显著提高血清总蛋白和球蛋白含量，显著提高血清球/清蛋白比值和IgG、 IgA含量。3、益生素能显著降低血清中总脂和胆固醇含量;显著提高血中钙、磷含量。4、益生素的添加量以添加0.2%时效果最好。5、益生素与黄霉素作用效果比较，益生素能更好地提高肉鸡免疫力，更有效 地降低血清中总脂和胆固醇含量，但增重效果不如黄霉素;益生素与黄霉 素联合使用，对血清蛋白的影响和试验前期钙的吸收有一定协同作用。说 明益生素可以部分替代黄霉素使用。更多还原

【Abstract】 A study was conducted to investigate the effects of probiotics on broilers’ performance, immune responses, serum biochemical parameters. The experiment was conducted as completely random block design. A total of 3776 one-d-old male commercial Avian broilers were fed on two group (with and without flavomycin) diets supplemented with graded levels of probiotics at 0, 0.2, 0.4, 0.6%. Birds were divided randomly into 8 treatments (six replicates per treatment and 60 broilers per replicate). Every treatment had a digestive group, including 112 birds, added 0.3% Cr2O3 into diet. This experiment was conducted in two periods: starter 0-21 and finisher22-42 ,days. Light was provided 24 h a day, feed and water were provided ad libitum during the entire experimental period. Body weight gain, feed consumption and feed efficiency (feed:gain) were checked on the d 21 and the d 40. Blood samples were collected on d 14 and d 40 to determine IgG, IgA, total protein, albumin, globulin, triglycerol, total cholesterol, Ca, P and T lymphocyte proliferation ratio. On each morning of d 21 and d 42, 64 broilers of d 21 and 48 broilers of d 42 from each digestive group were used to measure spleen, bursa F, thymus, cecal tonsils and the assimilation rate of nutrients.The results showed that: the birds given diet added probiotics (1) There was no significantly effect on feed consumption, feed efficiency and weight gain of starter phase (p>0. 05), but had significantly effect on DM, OM, CP, Ca, P and part of essential amino acid (p<0. 05). The digestibility of Met, Lys, Phe, He, His at starter phase and DM, OM, CP, Ca, P at full phase were significantly improved by the group given 0.2% probiotics (p<0. 05), weight gain was significantly increased at finishing phase (p<0. 05) while feed efficiency was decreased by the group given 0.4% probiotics (p>0. 05). (2) At starter phase, probiotics can improve spleen index, bursa F index and cecal tonsils area. There was significantly effect on spleen index (p<0. 05) and bursa F index (p<0. 01) by 0.4% probiotics, and cecal tonsils area was significantly increased by 0.2% probiotics (p<0. 01). At finishing phase, there was no significant influence on immune organs (p>0. 05). (3) There was obvious effect onserum IgG and IgA content but not effect on T lymphocyte proliferation ratio. The serum IgG, IgA content was significantly improved by 0.4% probiotics (p<0. 05). (4) Probiotics can increase total protein, globulin content and G/A. The globulin content and G/A were significantly increased by 0.2% probiotics (p<0. 05). (5) There was obvious influence on the content of serum Ca > P. The content of serum P at starter phase and serum Ca at finishing phase was significantly increased by the group given 0.2% probiotics (p<0.05). (6) Probiotics can decrease the level of serum triglycerol and cholesterol, and which was significantly decreased by 0.2% probiotics (p<0. 05). (7) There was no significantly different among the groups of probiotics, flavomycin and probiotics + flavomycin (p>0. 05).Based on the above results, it was suggested that:(1) Probiotics can increase the digestibility of essential amino acid, DM, OM, CP. (2) Probiotics can improve the chicken immune response increasing spleen index, bursa F index and cecal tonsils area significantly at starter phase and the serum IgG, IgA, total protein, globulin content and G/A at finishing phase. (3)Probiotics can increase the serum Ca and P content, decrease the serum triglycerol and cholesterol level. (4) The optimal probiotics supplementation level in broiler diet is 0.2%. (5) Compared with flavomycin, probiotics can improve the chicken immune response and decrease serum triglycerol and cholesterol level more efficiently, but the effect of probiotics on gain is less than flavomycin. Probiotics and flavomycin was used at the same time can effect serum protein content and promote the assimilation of Ca. So probiotics partially substituting flavomycin is possible.更多还原