饲粮钴添加水平对断奶至3月龄獭兔生长性能、屠宰性能、肌肉品质和皮张质量的影响

Effects of Dietary Cobalt Supplemental Level on Growth Performance,Slaughter Performance,Muscle Quality and Fur Quality of Weaned to 3-Month-Old Rex Rabbits

本试验旨在研究饲粮钴添加水平对断奶至3月龄獭兔生长性能、屠宰性能、肌肉品质和皮张质量的影响。选择体重相近的断奶獭兔200只,随机分为5组(每组40个重复,每个重复1只),分别饲喂在基础饲粮中添加0、0.1、0.4、1.6、6.4 mg/kg钴(以硫酸钴的形式)的试验饲粮。预试期7 d,正试期60 d。结果表明:在初始体重(IBW)无显著差异(P>0.05)的前提下,饲粮钴添加水平对终末体重(FBW)有显著影响(P<0.05),对平均日采食量(ADFI)有极显著影响(P<0.01),对平均日增重(ADG)和料重比(F/G)均无显著影响(P>0.05)。随着饲粮钴添加水平的升高,FBW和ADFI均先升高后降低,并且均在饲粮钴添加水平为0.4 mg/kg时最高。饲粮钴添加水平对獭兔的全净膛率、半净膛率和及肌肉品质指标[p H、失水率、剪切力以及肉色(亮度、红度、黄度值)]均无显著影响(P>0.05),随着饲粮钴添加水平的升高,全净膛率和半净膛率均有先升高后降低的趋势。饲粮钴添加水平对獭兔的皮张面积、皮张重量、皮张厚度均无显著影响(P>0.05)。随着饲粮钴添加水平的升高,皮张重量呈现先增加后降低的趋势,且在饲粮钴添加水平为0.4 mg/kg时最高。饲粮钴添加水平对胸腺指数、脾脏指数、肝脏指数均没有显著影响(P>0.05)。随着饲粮钴添加水平的升高,胸腺指数呈现先增加后降低的趋势,且在饲粮钴添加水平为0.4 mg/kg时达到最高。综合本试验测定指标,断奶至3月龄獭兔饲粮适宜的钴添加水平为0.4 mg/kg(基础饲粮中钴含量为0.27 mg/kg)。

This experiment was conducted to study the effects of dietary cobalt supplemental level on growth performance,slaughter performance,muscle quality and fur quality of weaned to 3-month-old Rex rabbits.Two hundred weaned Rex rabbits were randomly assigned into 5 groups with 40 replicates in each group and each replicate contained 1 rabbit. Rabbits in 5 groups were fed experimental diets which supplemented with 0,0. 1,0. 4,1. 6 and 6. 4 mg / kg cobalt（ in the form of cobalt sulfate） on the basis of a basal diet,respectively.The trial lasted for 7 days for adaptation and 60 days for test. The results showed that dietary cobalt supplemental level had significant influences on final body weight（ FBW）（ P〈0. 05） and average daily feed intake（ ADFI）（ P〈0. 01）,but had no significant influences on average daily gain（ ADG） and feed /gain（ F /G）（ P〉0. 05）. With the increase of dietary cobalt supplemental level,the FBWand ADFI tended to be increased firstly and then decreased,and the highest values appeared when dietary cobalt supplemental level was 0. 4 mg /kg. Dietary cobalt supplemental level had no significant influences on eviscerated ratio,half eviscerated ratio and muscle quality indices including pH,drip loss ratio,shear force and meat color（ L＊,a＊and b＊values）（ P〉0. 05）. However,with the increase of dietary cobalt supplemental level,the eviscerated ratio and half eviscerated ratio tended to be increased firstly and then decreased. Dietary cobalt supplemental level had no significant influences on fur area,fur weight and fur thickness（ P〉0. 05）. With the increase of dietary cobalt supplemental level,the fur weight tended to be increased firstly and then decreased,and the highest value appeared when dietary cobalt supplemental level was 0. 4 mg / kg. Dietary cobalt supplemental level had no significant influences on thymus index,spleen index and liver index（ P〉0. 05）. With the increase of dietary cobalt supplemental level,the thymus index tended to be increased firstly and then decreased,and the highest value appeared when dietary cobalt supplemental level was 0. 4 mg / kg. Considering all indices of this experiment,the appropriate dietary cobalt supplemental level is 0. 4 mg / kg for weaned to 3-month-old growing Rex rabbits（ the basal diet cobalt content is 0. 27 mg /kg）.