挤压膨化对棉粕营养成分及膨化棉粕对肉鸡生长性能的影响

Effects of extrusion and expansion on nutritional composition of cotton meal and extruded cotton meal on growth performance of broilers

试验旨在研究膨化加工对棉粕(Cottonseed meal,CM)的营养物质、游离棉酚含量以及在肉鸡饲粮中添加膨化棉粕(Extruded Cottonseed meal,ECM)对肉鸡生长性能的影响。首先,采用双螺杆干法挤压膨化机对饲料级CM进行膨化,对比测定CM和ECM的营养成分和游离棉酚的含量。其次,以CM和ECM为主要试验材料,选取960只21日龄AA肉鸡为试验动物,按体重一致的原则随机分成6个处理,每个处理8个重复,每个重复20只鸡。处理1饲喂添加6%CM饲粮,处理2、3、4、5、6分别饲喂添加6%、9%、12%、15%、18%的ECM的饲粮,各组饲粮中粗蛋白质和代谢能等营养水平均调配均衡,试验期21 d。结果表明:棉粕经过挤压膨化后粗脂肪极显著降低(P<0.01);棉粕膨化后游离棉酚含量极显著降低(P<0.01),从1745.05 mg/kg降低到385.94 mg/kg,降低率高达77.88%;同时,干法挤压膨化导致棉粕蛋白溶解度极显著降低(P<0.01)。当ECM和CM添加量均为6%时,6%ECM组的平均日增重(ADG)、末均重(FBW)、屠宰率和全净膛率均大于6%CM组,平均日采食量(ADFI)、料重比(F/G)、胸肌率、腿肌率和肝/体比均低于6%CM组(P>0.05);随着膨化棉粕添加量的增加,屠宰率先升高后降低,但差异不显著(P>0.05),腿肌率逐渐升高;血清生化指标方面,随着膨化棉粕添加量的增加到15%时,尿素氮的含量显著升高(P<0.05)。由此可见,干法挤压膨化加工能显著降低游离棉酚的含量,在肉鸡饲粮中添加适量的膨化棉粕与添加等量的棉粕相比可以提高肉鸡的生长性能和屠宰率。

The aim of the experiment was to investigate the effects of extruded on cottonseed meal(CM)nutrient,free gossypol content and extruded cottonseed meal(ECM)on growth performance of broilers.Firstly,the feed-grade CM was expanded using a twin-screw dry extrusion extruder,and the nutrient content and free gossypol content of CM and ECM were determined by comparison.Secondly,with the CM and ECM as the main test materials,960 health 21-day-old AA broilers were selected as experimental animals and randomly divided into 6 treatments according to the principle of body weight,each treatment was repeated 8 times,and each repeated 20 chickens.Treatment 1 was fed with 6% ordinary cottonseed meal(CM)diets,while treatments 2,3,4,5,6 were fed with 6%,9%,12%,15%,18% expanded cotton meal(ECM)Diets,the nutrient levels of crude protein and metabolic energy in the diets of each group are evenly balanced,and the test period is 21 days.The results showed that the crude fat of cottonseed meal was significantly decreased after extrusion(P<0.01).The content of FG was significantly decreased from 1745.05 mg/kg to 385.94 mg/kg(P<0.01),the reduction rate was 77.88%.At the same time,dry extrusion resulted the PS significant decrease in the cotton meal(P<0.01).When both ECM and CM were added 6%,the average daily gain(ADG),terminal average weight(FBW),slaughter rate and total net sputum rate of the 6% ECM group were greater than 6%CM group,and the average daily intake was observed.The amount of(ADFI),weight-to-weight ratio(F/G),chest muscle rate,leg muscle rate and liver-to-body ratio were all lower than 6%CM group(P>0.05).With the increase of the amount of puffed cotton aphid,the average daily feed intake,average daily gain,and feed-to-weight ratio of broilers decreased slightly,and the slaughter rate increased first and then decreased,but the difference was not significant(P>0.05),and the leg muscle rate gradually.Increased;serum biochemical index,with the increase of the amount of expanded cotton aphid,the urea nitrogen content increased significantly(P<0.05),uric acid content decreased significantly(P<0.05);It can be seen that the dry extrusion process can significantly reduce the content of free gossypol.Adding expanded cotton meal to the broiler diet can increase the growth performance and slaughter rate of broilers compared with adding cotton meal.