柑橘渣对抗旱王断奶犊牛生长性能和养分表观消化率的影响

Effects of citrus pulp on growth performance and nutrient apparent digestibility of Droughtmaster calves

为了研究柑橘渣对抗旱王断奶犊牛生长性能和养分表观消化率的影响,试验选择5月龄、体重相近的健康抗旱王断奶犊牛32头,按月龄和体重相近的原则随机分为4个处理组,每个处理组8头牛,依次为对照组、10%组、20%组和30%组,对照组饲喂基础日粮,10%组、20%组、30%组分别饲喂用10%、20%、30%柑橘渣等量替代基础日粮中玉米的日粮,并从每个处理组中选择3头接近平均体重的犊牛进行消化代谢试验,分别测定了试验牛的生长性能和养分表观消化率。结果表明:添加10%(10%组)、20%(20%组)、30%(30%组)柑橘渣等量替代日粮中的玉米对断奶犊牛生长性能影响不显著(P>0.05);4个处理组间干物质、有机物、粗蛋白、中性洗涤纤维和酸性洗涤纤维以10%组最高,其次为对照组、20%组,30%组最低,虽然钙和磷的表观消化率随着柑橘渣添加量的增加而呈逐渐降低的趋势,但差异均不显著(P>0.05)。说明柑橘渣可以替代断奶犊牛日粮中部分玉米,在本试验条件下,抗旱王断奶犊牛日粮中用10%～20%的柑橘渣替代玉米较为适宜。

The objective of this study is to investigate the effects of citrus pulp on growth performance and nutrient digestibility of Droughtmaster calves. A total of thirty-two 5-month-old healthy Droughtmaster calves were selected and randomly allotted into 4 groups ( 8 for each group) according to similar age and similar weight. The grouth performance and digestibility of Droughtmaster calves were detected.The groups were provided four food regimes respectively,control group,10% group,20% group and 30% group. The 10% group,20% group and 30% group used citrus pulp instead of equivalent corn. Digestion experiment was carried out using 3 calves of near average weight from each group. The results showed no significant difference among growth performance of each group when added different citrus pulp( P>0. 05) . The apparent digestibility of dry matter,organic matter,crude protein,neutral detergent fiber and acid detergent fiber presented the highest in 10% group,then the control group and 20% group;The 30% group was the lowest in terms of such digestibility. By contrast,no difference was observed in the apparent digestibility of calcium and phosphorus( P>0. 05) ,but had a decrease trend with the increasing amount of citrus pulp.It indicats that citrus pulp can replace some corn in the diet of weaned calves.Under the experimental conditions,the diet containing 10%-20% citrus pulp was suitable.