Measurement Of Several Meat Qualities Of Huainan Spotted Chicken And Its Studies By RAPD Marker

Huainan spotted-brown chicken, is a native breed. The flock is of high purity. A significant genetic progress on the 8-week body weight has been selected after nine generations.In order to further investigate the flock' s variation of early growth rate, dressing traits and meat qualities during selection, 198 healthy startings of the 9th generation were selected in this experiment. The diet was basically the same as those of the former 8 generations, Floor-reared till 8 weeks and measured for their early growth rate. 57 chickens (30 cocks, 27 hens) were randomly selected for measuring dressing traits and meat qualities at 8 weeks. They were analyzed for the variations of meat qualities by sexes, sampling locations, and generations. RAPD molecule markers were used for analyzing the correlation between production performance and bands of RAPD genetic markers by blood samples. The results are as follow:Average body weight of rooster and hen at 8-week (measured as 998. 00 + 102. 58g and 801. 68 + 67. 24g respectively) are fairly uniform after selection within sex. There were significant differences between sexes at 4-week and 8-week (p<0.01). Body weight at 8-week of the 9th generation has been improved compared to the zero generation, the 3th generation and the 5th generation with57. 8%, 28. 0% and 12.6% respectively. Huainan spotted-brown chicken, compared to other native breeds, is of medium growth rate at early stage.Carcass analysis showed that meat qualities have been improved after selection. Compared to the 7th generation, dressing percentage of eviscerated yield, percentage of thigh muscle and percentage of breast fat yield of Huainan spotted-brown chickens have been improved by 3.9%, 4.39%, 5.00%, 1.67%, 0.78% respectively. The results also showed carcass traits were different from those of other native breeds in the same age. Measurements of meat quality showed that each trait had no significant difference (p>0. 05) between sexes but significant difference among sample locations. Early growth rate improvement hasnegative effect on physical traits that were generally worse than those of the results indicated in the 7th generation. Water holding capacity was high while a* value was lower in the 9th generation. The meat qualities of Huainan spotted-brown chicken need to be improved further when the growth rate has been well improved.As regard to the chemical traits, moisture content of muscle and crude fat depisation have been improved but crude protein has a little descending tendency. Amino acids profile in Huainan spotted-brown chicken is relatively stable. The content of glutamine as the main flavor amino acids, is higher in rooster than in hen and is also higher than other native breeds like Shiqi cross breed. Analysis of fatty acid profile showed that content of non-saturated fatty acids which appears different variation comparing with other local breeds occupied 61.96%. Diameter of muscle fiber is not apparently different among sex and sample sites of the 9th generation yet apparently different among generations. Diameters of breast and thigh muscle fibers of are apparently thinner than the 7th generation (p<0.01).Analysis by RAPD markers showed that genome of Huainan spotted-brown chicken is rather pure in genetic, for the band sharing frequency in Huainan spotted-brown chicken is 0.7862. Co-efficiency of genetic similarity is 1.0428. There were diversified polymorphism bands in Huainan spotted-brown chicken, 11 bands showed tight correlation and 3 specific bands ( measured as S87D- crude protein%, S87D- arachidonic acid%, S102A~arachidonic acid% and S108B-fibre diameter respectively) showed significant correlations to production performances. Further study will be focused on whether specific bands can be utilized as accessory selection on meat quality.