益生素添加水平对断奶獭兔肠道免疫力的影响

Effects of the Level of Probiotics Added on Immune Capability of Gut in Weaned Rex Rabbits

[目的]研究不同益生素添加水平对断奶獭兔肠道免疫能力的影响。[方法]选择80只体重相近的35日龄的健康断奶獭兔,按公母各半随机分为4个组(I、Ⅱ、Ⅲ、Ⅳ组),分别饲喂添加0、0.1、0.2和0.4 g/kg水平益生素的饲粮,预试期7 d,试验期60 d。试验结束后测定腹泻率及十二指肠、回肠与直肠的p H和SIg A含量。[结果]在饲料中添加益生素对断奶獭兔的腹泻率、平均日增重与料重比均有影响显著(P<0.05);其中Ⅲ组的日增重最高、料重比及腹泻率最低,Ⅲ组的日增重比I组升高10.96%,Ⅲ组料重比和腹泻率分别比I组降低7.37%及59.44%;肠道环境p H随益生素添加水平的升高先降低后回升,但只有Ⅱ与Ⅲ组的盲肠环境p H发生了显著变化(P<0.05),与I组相比分别低了3.03%与4.43%;回肠与十二指肠的SIg A含量不受益生素添加水平的影响(P>0.05),Ⅳ组的空场SIg A含量较I组高8.84%(P<0.05)。[结论]断奶獭兔基础日粮中添加适宜的益生素可以降低腹泻率,影响其肠道环境与提高肠道免疫屏障,最佳添加水平为0.2 g/kg。

[ Objective ] To study the effect of different level of probiotic supplement on immune capability of gut in weaned Rex rabbits. [ Method] Eighty healthy 35-day-age rabbits （half male and half female）were chosen and randomly divided into 4 groups（ group Ⅰ, group Ⅱ, group Ⅲ and group Ⅳ）, and they were fed a probiotics-supplemented diet containingO, 0.1,0.2, 0.4 g/kg for 60 days. At the end of the feeding experiment, the diarrhea incidence, and pH and SlgA of gut were measured and analyzed. [ Result ] The results showed that the diar- rhea incidence and daily gain and feed/gain were all affected obviously by adding with probiotics. The daily gain was the highest, and both the feed/gain and diarrhea incidence were the lowest in these four groups. Compared with group Ⅰ , the daily gains improved by 10.96% （ P 〈 0. 05） and feed conversion and diarrhea incidence reduced by 7.37% and 59.44 （ P 〈 0. 05 ） respectively in group Ⅲ. With the increase of adding probiotics level, the pH tended to be increased firstly and then decreased. The pH in the caecum of group Ⅱ and of group Ⅲ was 3.03% lower and 4.43% lower than that in group I ＇ s, respectively. The level of added probiotics had no significant influence on the contents of SIgA in rabbits＇ ileums and duodenums （ P 〉 0.05 ）, but the content of SⅠgA in jejunum was increased by 8.84% （ P 〈 0.05 ） in Ⅳ group compared with control group I. [ Conclusion] It concluded that adding an an appropriate level of probiotics into the basal diet can reduce diar- rhea incidence and improve gut immune barrier in weaned Rex rabbits, and the optimal supplementation level was 0.2 g/kg.