D-泛酸钙在黄羽肉鸡中的耐受性评价

Evaluation of Tolerance of D-Calcium Pantothenate in Yellow-Feathered Broilers

本试验通过研究饲粮添加不同水平D-泛酸钙对黄羽肉鸡生长性能、血常规指标、血清生化指标、器官指数和组织病理学的影响,以评价肉鸡对D-泛酸钙的耐受性。试验采用单因素完全随机设计,选用640羽健康且体重相近的1日龄黄羽肉公鸡(梅黄1号),随机分为4个组,每组8个重复,每个重复20羽。各组分别在基础饲粮中添加0(对照)、25、125和250 mg/kg的D-泛酸钙(以维生素B5计,本底维生素B5含量:前期8.0 mg/kg,后期6.0 mg/kg)。试验期70 d,分为1~35日龄(前期)和36~70日龄(后期)2个阶段。结果表明:1)1~35日龄,与对照组相比,饲粮添加25 mg/kg D-泛酸钙显著提高肉鸡平均日增重(ADG)(P<0.05),显著降低料重比(F/G)(P<0.05);1~70日龄,与对照组相比,饲粮添加25和125 mg/kg D-泛酸钙显著提高ADG(P<0.05),饲粮添加125 mg/kg D-泛酸钙显著降低F/G(P<0.05)。2)与对照组相比,饲粮添加不同水平D-泛酸钙对肉鸡血常规指标和血清生化指标均无显著影响(P>0.05);饲粮添加25~250 mg/kg D-泛酸钙显著提高肉鸡70日龄血清维生素B5含量(P<0.05),而对35日龄血清维生素B5含量无显著影响(P>0.05)。3)与对照组相比,饲粮添加不同水平D-泛酸钙对肉鸡各器官指数均无显著影响(P>0.05),肉鸡主要器官也均未观测到组织病理学变化。综上可知,黄羽肉鸡对D-泛酸钙的耐受剂量可达250 mg/kg,是有效剂量(25 mg/kg)的10倍。

This experiment was conducted to investigate the effects of different dietary levels of D-calcium pantothenate on growth performance,blood routine indices,serum biochemical indices,organ indices and histopathology of yellow-feathered broilers,in order to evaluate the tolerance of D-calcium pantothenate in broilers.Using a single-factor completely randomized design,a total of 640 healthy 1-day-old yellow-feathered cocks(Meihuang No.1)with similar body weight were randomly divided into 4 groups with 8 replicates per group and 20 broilers per replicate.Broilers in the four groups were fed basal diets supplemented with 0(control),25,125 and 250 mg/kg D-calcium pantothenate(calculated by vitamin B 5,and the background vitamin B 5 content was 8.0 mg/kg in the early stage and 6.0 mg/kg in the late stage),respectively.The experiment lasted for 70 days and was divided into two stages as 1 to 35 days of age(early stage)and 36 to 70 days of age(late stage).The results showed as follows:1)from 1 to 35 days of age,compared with the control group,dietary 25 mg/kg D-calcium pantothenate significantly increased the average daily gain(ADG)of broilers(P<0.05),and significantly decreased the ratio of feed to gain(F/G)(P<0.05);from 1 to 70 days of age,compared with the control group,dietary 25 and 125 mg/kg D-calcium pantothenate significantly increased ADG(P<0.05),and dietary 125 mg/kg D-calcium pantothenate significantly decreased F/G(P<0.05).2)Compared with the control group,different dietary levels of D-calcium pantothenate had no significant effects on blood routine indices and serum biochemical indices of broilers(P>0.05);dietary 25 to 250 mg/kg D-calcium pantothenate significantly increased the serum vitamin B 5 content of broilers at 70 days of age(P<0.05),but had no significant effects on the serum vitamin B 5 content at 35 days of age(P>0.05).3)Compared with the control group,different dietary levels of D-calcium pantothenate had no significant effects on organ indices of broilers(P>0.05),and no histopathological changes were observed in major organs of broilers.In conclusion,the tolerated dose of D-calcium pantothenate in yellow-feathered broilers can reach 250 mg/kg,which is 10 times of the effective dose(25 mg/kg).