【作者】 李宝全；

【导师】 尹逊河； 王树迎；

【作者基本信息】 山东农业大学 ， 基础兽医学， 2002， 硕士

【摘要】 本研究分两个试验，试验一探讨了山东省三个地方品种肉鸡以及AA肉鸡肌肉的某些组织学性状与理化特性，重点测定了肌纤维直径、肌纤维密度、肌肉的剪切值、系水力与脂肪含量，分析了组织学性状与理化性状的相关性。比较了不同性别、不同部位以及不同品种的上述性状的差异，揭示了肉质变化的某些规律。试验二以山东省三个地方品种肉鸡和速生型肉鸡杂交，测定不同日龄杂交后代的上述肌肉组织学性状与理化特性，确定肉质的变化特点以及对肉质有益的杂交组合。 试验一 地方品种肉鸡肉品的某些组织学性状与理化特性的研究 对山东省三个地方鸡种寿光鸡、寿光F₃鸡、鲁西黄鸡以及速生鸡AA肉仔鸡的肌肉某些组织学与理化性状进行测定，宰杀取样在相近体重时的日龄进行，饲料营养水平按肉仔鸡饲养标准，每个品种取样10只，分别取样于胸肌、腿肌的相同部位，做冰冻切片，苏木素-苏丹Ⅲ染色，在显微镜下用测微尺测定肌纤维密度与直径，用嫩度计测量肌肉的剪切值，测量肌肉的失水率及脂肪含量，并作相关分析与差异比较，结果表明：肉鸡肌纤维密度与直径分别与肌肉物理剪切值呈极显著负相关与极显著正相关（p〈0.01）肌纤维密度在种间的差异性高于肌纤维直径与剪切值，是衡量肌肉嫩度的有效指标。肌纤维的密度和直径性状与肌肉的保水力及脂肪含量的关系不显著，不能用来衡量肌肉的加工稳定性及香味。对不同部位（胸肌与腿肌）肌肉的肌纤维性状与理化特性的比较表明：四个品种鸡腿肌的肌纤维密度均大于胸肌；腿肌脂肪含量均大于胸肌；除AA肉鸡外，腿肌肌肉的失水率均小于胸肌。公鸡与母鸡相比，肌肉的嫩度差异不显著，公鸡肌肉嫩度略好于母鸡，三个山东省地方品种肉鸡的肌纤维密度均显著高于AA肉仔鸡（p〈0.05），而肌肉的失水率差异不显著（p〉0.05），肌肉脂肪含量均低于AA肉仔鸡。结果表明山东地方品种肉鸡具有肉质细嫩的遗传基础，还具有用速生肉鸡改良产肉性能与脂肪含量的潜力。三个山东地方鸡种中，以鲁西黄鸡肌肉肌纤密度最高，嫩度最优。 试验二 杂交系肉鸡肉品的某些组织学性状与理化特性的研究 根据速生鸡与地方肉鸡的特点，设计出五种杂交组合，隐性白羽鸡×寿光鸡；AA鸡×寿光鸡；隐性白羽鸡×F₃鸡；寿光鸡×隐性白羽鸡；狄高鸡×鲁西黄鸡。每个杂交系取样10只，公鸡母鸡各5只，宰杀取样的时间为10周龄与13周龄。测定胸肌与腿肌的组织学与理化指标，包括肌纤维密度与直径，物理剪切值，系水力与脂肪含量。结果表明：13周龄的杂交鸡与10周龄相比肌纤维直径增粗，肌纤维密度 李宝全：优质肉鸡肉品的某些组织学性状与理化特性的研究度降低，肌肉的剪切值增加，表示肌肉的嫩度下降。对肌肉失水率与脂肪含量的比较表明，五个杂交系的鸡均表现为随日龄增加失水率下降，脂肪含量增加，表明适当增加上市日龄，可提高肌肉的加工性能，提高肉的香味。 与亲本地方鸡比较，杂交鸡的肌纤维直径增粗，肌纤维密度有所下降，肌肉的嫩度有所下降，但某些组合下降程度较低，依然保持较好的嫩度，杂交鸡的脂肪含量均比亲本地方鸡有极显著提高（p＜0刀 1），但是杂交鸡的失水率比亲本鸡种有显著提高（P＜0刀5）。综合比较表明：速生肉鸡与地方肉鸡杂交是提高产肉性能，改善肉的香味，生产优质鸡肉的有效途径。对五种不同杂交组合，比较分析表明：速生鸡作父本对肉质嫩度与香味的保持好干以地方鸡种作父本（以寿光鸡与隐性白鸡正反交做对比）。隐性白鸡作父本与寿光鸡杂交肉质嫩度的保持与脂肪含量提高稍高于以AA肉鸡作父本。五种杂交组合中，以狄高鸡与鲁西黄鸡杂交肉质最嫩，隐性白X寿光其次。脂肪含量以隐性白X寿光最高，狄高X鲁西黄其次，以上这两种杂交模式在生产中应值得重视。更多还原

【Abstract】 Two experiment were conducted in present research. In experiment one some histological, physical and chemical characteristics of meat from three Shandong local breeds poultry and AA broiler was determined. These characteristics concluds muscle fiber diameter, density, phisical sheering value, capacity of keeping water and the properation of adipose. The correlation between histological characteristics and physical and chemical ones was analysed.The difference in such characteristic as before between different breeds, sexes and body parts was tested and so the regulation of change in meat quality was disclosed. In experiment two, the local breeds foultry was crossed by fast-growth ones. The Five characteristic of meet was measured just as experiment one. In order to find the change of meat quality with age, we removed the sample twice. The first is at 10 weeks old and the other is at 13 weeks old. Consequently, the better mode of combination in meat quality can be determined by the experiment.Experiment one. Reseach on some histological, physical and chemical characteristics of meat from Shandong local breeds poultry.Three shandong local breeds foultry including shouguan chick, shouguan F3 chick and Luxi Yellow chick as well as AA broiler was killed in the same weight and their meat sample on the same part of breast and leg was removed. One sample was used to make ice-frozen tissue spender and the muscle fiber diameter and density was measured under microb. Physical sheering value of meat was determined by sheering device and the capacity of holding water and ratio of fat was tested, too. Correlation and difference anylasis between the characteristics was carried out. The important findings are that: There was significent positive relation between muscle fiber density and sheering value, and the relation between muscle fiber density or diamete and capacity of keeping water or28property of fat is not significent (p>0.05). Comparison between breast meet and leg meat show that the later"s slendemess excels to the first and so was the ratio of fat. Apart from AA broiler, the capacity of holding water of leg meet is stronger than breast meet. There was no singnificent difference in meat slendemess between male and female chicken. From comparison between diiferent breeds of chicken we can find that the density of muscle fiber of all the three local breeds is much more than AA broiler(p<0.01) and the ratio of fat is lower than AA-broiler obviously(p<0.05). But the difference of capacity of holding water is not significent (p>0.05). all the results embodys the fact that muscle fiber density is a valid factor to evaluate meat’s slendemess and the Shandong local breeds chicken have the genetic foundation for slender meat as well as the potence to increase ratio of fat by hybrid. The sequency of meat slendemess is Luxi yellow chick, shouguan chick, F3 chick and AA broiler.Experiment two, Reseaeh on some histological, physical and chemical characteristics of meat in mode of hybrid chicken.According to the feature of fast-growth and local breeds chicken, five hybrid combination was designed. They are Yinxing white chickxshouguan chick; AA chick * shouguan chick; Yinxing white chick* F3 chick, shouguan chick x Yinxing white chick; Digao x LuXi Yellow chicken. The chicks including five cocks and five hens was picked up random on 70 days and 90 days after breed respectively, some histological and physical and chemical characteristics was measured just as experiment one. The important finding is that: Compared with 70 days old chicken, The 90 days chicken have much more wider and less denser muscle fiber no matter it is from breast meet or leg meat. At the sametime, it’s sheering value and the ratio of fat increased but the ratio of losing water droped with the age increasing.All these results indicate that to extend the age of entering market can be helpful to augment poultry’s processing adaptability and improve their taste.Compared with their parents local breeds, the hybrid chicken’s muscle fiber becom更多还原