【作者】 刘冰；

【导师】 杨宁；

【作者基本信息】 中国农业大学 ， 动物遗传育种与繁殖， 2005， 硕士

【摘要】 选用隐性白鸡、北京油鸡以及杂交鸡(北京油鸡为父本、隐性白鸡为母本)为试验材料,相同条件下饲养14周。研究不同品种鸡在生长性能和屠宰性状上的差异,并重点分析不同品种鸡的肌纤维发育规律及肌纤维与肉质的关系。 隐性白鸡的生长速度大于杂交鸡大于北京油鸡,8周龄时隐性白鸡的平均体重达1308.86 g,杂交鸡的体重为1030.5 g,而北京油鸡仅630.75 g。公鸡的生长速度较快,6周龄后公鸡的体重显著大于母鸡(P<0.01)。屠宰测定表明:10周的隐性白鸡的屠宰率(90%)、全净膛率(64%)大于14周龄,说明隐性白鸡适合10周龄屠宰,而北京油鸡则适合14周龄屠宰(86%,59%)。 石蜡切片和鲜样测定的结果相关性高(r=0.92,P<0.0001)。随着鸡的生长肌纤维直径越来越粗。腿肌肌纤维的直径大约比胸肌肌纤维直径高20%。切片测定结果表明,隐性白鸡和北京油鸡差异极显著(P<0.01),而杂交鸡处于隐性白鸡和北京油鸡之间。在初生时隐性白鸡、杂交鸡、北京油鸡的腿肌、胸肌肌纤维直径差异不显著(P>0.05),14周龄时腿肌肌纤维直径分别为56.93μm、49.29μm、42.89μm,差异极显著(P<0.01)。 随着时间的推移,肌纤维的密度越来越小。胸肌肌纤维的密度大于腿肌肌纤维的密度,腿肌肌纤维密度大约是胸肌的60%～70%。14周龄时,北京油鸡的胸肌肌纤维密度密度(888.55根/mm~2)大于隐性白鸡(561.89根/mm~2)(P<0.01)(腿肌肌纤维密度,也是隐性白鸡和北京油鸡差异极显著,P<0.01),杂交鸡处于二者之间。 在12周龄时,胸肌肌纤维直径、腿肌肌纤维直径与体重、胸肌重、腿肌重呈极显著的正相关(P<0.0001,0.65～0.75)。肌纤维直径与剪切力呈正相关(r=0.10～0.12),表明肌纤维直径越小,剪切力越小,肌肉越细嫩。肌纤维密度与胸肌重、腿肌重、体重呈负相关(-0.6～-0.8,P<0.0001),与嫩度呈负相关(-0.2左右)。更多还原

【Abstract】 Recessive White Plymouth Rock(RWPR), Beijing-fatty and Beijing-fatty ((?) )× Recessive White Plymouth Rock ((?)) (C) were fed to 14 weeks to investigate the development character of growth, slaughter performance, and muscle fiber. The association between muscle fiber and meat quality was also anlyzed.Recessive White Plymouth Rock (RWPR) grew faster than Cross and Beijing-fatty (BF). At 8 wks of age, body weight (BW) of RWPR amount to 1308.86 g and body weight of Cross is 1030.5g ,while BF only 630.75 g. BW of male chickens were greater (P<0.01) than that of females after 6 wks of age. The dressed BW (90%), percentage of eviscerated carcass (64%) of RWPR at 10 wks of age were greater than those of 14 wks, indicating that RWPR is suitable for slaughter at 10 wks of age. However, BF will get a good slaughter performance at 14 wks of age.The muscle fiber parameters measured by fresh muscle were highly correlated to those by paraffin slice protocol (r=0.92, P<0.01). The diameter increased with age, and the diameter of leg muscle was greater than that of breast muscle by 20% approximately. Results from slice showed that the diameter of muscle fiber of RWPR was greater than that of BF (P<0.01) after 6 wks of age, while the Cross in the between. There was no difference among the diameters of leg or breast muscle fiber at hatch in RWPR, Cross, and BF (P>0.05), while the diameter of leg muscle for RWPR, Cross, and BF (56.93, 49.29, and 42.89um, respectively) differed at 14 weeks of age (P<0.01).The muscle fiber density decreased with age and the density of breast muscle was greater than that of leg muscle by nearly 60-70%. The density of BF (888.55 unit/mm~2) was greater (P<0.01) than that of RWPR (561.89 unit/mm~2) at 14 wks of age, while that of Cross was between RWPR and BF.The diameter of leg and breast muscle fiber was positively correlated to BW, leg and breast muscle weight (r=0.65-0.75, P<0.0001) at 12 wks of age. The diameter was positively associated (r=0.10-0.12) with shear force, suggesting that the thinner the fiber was, the tenderer the muscle was. The density of muscle fiber was negatively correlated to body weight, leg and breast muscle weight (r=-0.6~0.8, P<0.0001respectively), and tenderness (r=-0.2 approximately).更多还原