桑叶提取物对矮脚黄鸡生长性能、屠宰性能及肉品质的影响

摘要

本试验旨在研究饲粮中添加桑叶提取物对矮脚黄鸡生长性能、屠宰性能及肉品质的影响.选择21日龄、初始体重相近的矮脚黄鸡母鸡300羽,随机分为4组(每组5个重复,每个重复15羽),分别饲喂4种不同的饲粮:Ⅰ组(对照组)饲喂基础饲粮,Ⅱ组饲喂添加0.2%桑叶提取物的基础饲粮,Ⅲ组饲喂添加0.5%桑叶提取物的基础饲粮,Ⅳ组饲喂添加0.8%桑叶提取物的基础饲粮.试验期为53 d.结果表明:1)与对照组相比,在饲粮中添加0.2%、0.5%和0.8%的桑叶提取物可显著提高平均日增重和平均日采食量(P<0.05),有降低料重比的趋势,但差异不显著(P>0.05).2)与对照组相比,在饲粮中添加桑叶提取物对矮脚黄鸡的屠宰性能无显著影响(P>0.05),但可使屠宰率、半净膛率略有提高.3)随着桑叶提取物添加水平的增加,腿肌和胸肌亮度(L?)、红度(a?)、黄度(b?)值呈升高趋势.各添加桑叶提取物组腿肌和胸肌pH24 h均显著高于对照组(P<0.05).腿肌和胸肌嫩度随着饲粮中桑叶提取物添加水平的增加而提高,其中Ⅳ组腿肌嫩度显著高于对照组(P<0.05).4)与对照组相比,各添加桑叶提取物组胸肌和腿肌中粗蛋白质和粗脂肪含量均有不同程度的提高,但差异均不显著(P>0.05).5)与对照组相比,在腿肌和胸肌中,除精氨酸、异亮氨酸、亮氨酸和赖氨酸含量在某些添加桑叶提取物组中有显著变化(P<0.05)外,其他氨基酸含量在各添加桑叶提取物组中均无显著变化(P>0.05).各添加桑叶提取物组腿肌和胸肌中必需氨基酸/非必需氨基酸均与对照组无显著差异(P>0.05).6)随着桑叶提取物添加水平的增加,各添加桑叶提取物组腿肌和胸肌中饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)含量呈逐渐上升趋势,不饱和脂肪酸(UFA)、多不饱和脂肪酸(PUFA)、必需脂肪酸(EFA)、ω-6和ω-3含量以及UFA/SFA均呈逐渐下降趋势.由此得出,在饲粮中添加桑叶提取物可有效提高矮脚黄鸡的生长性能和肉品质.%This experiment was aimed to investigate the effects of mulberry leaf extract on growth perform-ance, slaughter performance and meat quality of yellow dwarf chickens. Three hundred 21-day-old yellow dwarf chickens with the similar initial body weight were randomly divided into four groups with five replicates per group and 15 birds per replicate. Chickens in four groups were fed a basal diet(group Ⅰ, as control group),the basal diet supplemented with 0.2% mulberry leaf extract(groupⅡ),the basal diet supplemented with 0.5% mulberry leaf extract(group Ⅲ)and the basal diet supplemented with 0.8% mulberry leaf extract (group Ⅳ), respectively. The experiment lasted for 53 days. The results showed as follows: 1)compared with the control group, diet supplemented with 0.2%,0.5% and 0.8% mulberry extract could significantly in-crease the average daily gain(ADG)and average daily feed intake(ADFI)(P<0.05),and had a decreasing tend in feed/gain,but no significant difference was observed(P>0.05).2)Compared with the control group, diet supplemented with mulberry extract had no significant differences in slaughter performance(P>0.05),but tended to increase the dressing percentage and half eviscerated yield percentage. 3)With the increase of mul-berry leaf extract supplemental level, the values of lightness(L?), redness(a?)and yellowness(b?)of breast muscle and leg muscle showed an increase trend. The pH24 hof breast muscle and leg muscle in supple-mented with mulberry leaf extract groups were significantly higher than that in control group(P<0.05). The tenderness of breast muscle and leg muscle increased with the increase of mulberry leaf extract supplemental level, and the significant increase in group Ⅳ was found compared with control group(P<0.05). 4)Com-pared with the control group, the crude protein and crude fat contents in breast muscle and leg muscle in sup-plemented with mulberry leaf extract groups had different degrees increase but with no significant differences (P>0.05). 5)There were no significant differences in most amino acid contents in breast muscle and leg mus-cle in supplemented with mulberry leaf extract groups(P>0.05)except lysine(Lys), arginine(Arg), iso-leucine(Ile)and leucine(Leu)contents in breast muscle and leg muscle had significant changes in some sup-plemented with mulberry leaf extract groups(P<0.05). No significant difference in the ratio of essential amino acid to non-essential amino acid was observed between supplemented with mulberry leaf extract groups and control group(P>0.05). 6)The saturated fatty acid(SFA), monounsaturated fatty acid(MUFA)contents in breast muscle and leg muscle had trend to increase with the increase of mulberry leaf extract supplemental level, and the unsaturated fatty acid(UFA),polyunsaturated fatty acid(PUFA),essential fatty acid(EFA), ω-6 and ω-3 contents, and UFA/SFA in breast muscle and leg muscle had trend to decrease with the increase of mulberry leaf extract supplemental level. It is indicated that mulberry leaf extract supplementation can effec-tively improve the growth performance and muscle quality of yellow dwarf chickens.