Study Of Mule Ducks’ Production Performance And Its Genetic Factors

In this study, the mule ducks from Five different groups that Muscovy crossed with ducks of five different dometstic breeds, and cherry valley ducks as control group, which were housed under the same conditions for 12 weeks, were used to study. The aims of his study were:(1) to screened out the optimum combination of hybrid by analysis of 0-8 week growth performance,8-week-old meat quality and economic benefits; (2) to study meat quality, histological characteristics of muscle fiber, and the relationship between meat quality and muscle fiber; (3) to analyze the expression differences of three genes of MSTN(Myostatin), IGF-1 (Insulin-like growth factor) and PPARa(Peroxisome proliferator-activated receptora) in breast muscle, leg muscle, liver and heart tissues from 8-week mule ducks and cherry valley ducks using real-time fluorescent quantitative PCR, and to investigate the effects of gene expression on meat quality and muscle fiber. The main results were showed as following:1. The efficiency of artificial insemination of Muscovy and domestic ducks was improved after the factors reducing the rate of artificial insemination were investigated and effective measures were taken to overcome a barrier of body size of Muscovy duck and Shaoxing, Liancheng White.2. The early growth rate of mule ducks in different crossing groups and Cherry Valley ducks were very high, with a peak of body weight gain in the first 5 weeks. The average weight of 3-8 weeks of Cherry Valley ducks were significantly higher than mule ducks (P<0.05).8-week’s weight of mule ducks from Group III (1.87 kg), group V (1.89 kg) were significantly higher than the other three crosses (P<0.05). But efficiency of feed utilization of group III (36.29%) was higher than group V (31.05%) and others3.8-week slaughter and eviscerated rate of mule ducks and Cherry Valley duck were higher than 80% and 60%, respectively, which showed good meat performance, slaughter (91.0%) and eviscerated rate (76.7%) of mule ducks in group III than the others (P>0.05), there were no significant differences of the water content, muscle drop loss, pH value, meat color, percentage of meat cooking of mule ducks between Group III and other groups, some meat quality traits of Group III were better than cherry valley ducks. Group III (Muscovy♂×(Lijia ducks♂×Liancheng ducks♀)♀) was regarded as optimum combination of hybrid.4. Histology characteristics of breast and leg muscle fiber in mule ducks and cherry valley ducks were comparatively analyzed, muscle fiber diameter in breast (16.45μm♂, 13.05μm♀) and leg (34.05μm♂,28.75μm♀) of mule ducks were lower than cherry valley duck’s (17.40μm♂,14.95μm♀; 36.85μm♂,29.85μm♀) respectively, breast muscle fiber diameter was lower in breast than leg, muscle fiber diameter of female duck was smaller than male duck’s. Muscle fiber spacing of male mule duck and male cherry valley duck were significantly higher than female mule duck and female cherry valley duck respectively (P<0.01).5. Expression differences of MSTN, PPARαand IGF-Ⅰgenes in breast muscle, leg muscle, liver and heart of mule ducks and cherry valley ducks 8 weeks old were studied by real-time fluorescent quantitative PCR. the mRNA expression level of IGF-Ⅰand PPARαin liver were highest in these four tissues, while lower in leg muscle and breast muscle. MSTN mRNA was highly expressed in leg muscle and breast muscle than in other tissues, and it was higher in mule duck than in cherry valley duck. Further analysis showed that the correlation of expression level of MSTN mRNA and muscle fiber diameter was negative, the correlation of expression level of IGF-Ⅰm RNA and PPARαm RNA and PH value of breast muscle and leg muscle were positive, which may effect the meat quality and histological features of muscle fibers.