温州红鸡生长曲线拟合与最佳上市周龄分析

Growth curve fitting and the optimal marketing age of Wenzhou Red chicken

探究温州红鸡生长发育规律和不同周龄温州红鸡屠宰性能、肌肉品质的差异,为确定最佳上市周龄和高效养殖提供理论依据。利用Logistic模型、Gompertz模型和Von Bertalanffy模型对温州红鸡0~24周龄的生长曲线进行拟合分析;分别选取26、30和34周龄的温州红鸡各20只(公母各半),测定屠宰性能、肌肉品质。结果表明:3种非线性模型均可以较好地拟合温州红鸡的生长,拟合度(R2)均达到0.99以上,其中Von Bertalanffy模型更适合公鸡(R^(2)=0.998 2),Gompertz模型更适合母鸡(R^(2)=0.997 3)。屠宰率达到90%以上,全净膛率达到68%以上。公鸡、母鸡在各周龄时的半净膛率、全净膛率、胸肌率、腿肌率、剪切力、水分含量、粗灰分含量和粗蛋白含量无显著差异,剪切力随着周龄的增长逐渐增大;30周龄公鸡的粗脂肪含量最高,26周龄公鸡的总钙含量最高,26周龄、30周龄公鸡的总磷含量显著(P<0.05)高于34周龄公鸡;母鸡在30周龄总钙含量和粗脂肪含量较高。胸肌中共检测出16种氨基酸,30周龄母鸡的呈味氨基酸含量高于其他周龄,公鸡的呈味氨基酸含量随周龄增长逐渐降低;胸肌中不饱和脂肪酸总量高于饱和脂肪酸,34周龄母鸡和30周龄公鸡不饱和脂肪酸含量最高。30周龄时每只公鸡生产利润为46.79元,母鸡生产利润为18.73元。综上所述,温州红鸡母鸡在30~34周龄上市为宜,公鸡在30周龄上市为宜。

The purpose of this experiment was to investigate the growth and development patterns of Wenzhou Red chicken,along with the differences in slaughter performance and muscle quality at different ages,aiming to provide a theoretical basis for determining the best marketing age and efficient farming.The growth curve of Wenzhou Red chicken from 0 to 24 weeks old was analyzed by fitting it to Logistic,Gompertz,and Von Bertalanffy models;20 chickens of each age group at 26,30,and 34 weeks(half rooster and half hen)were selected to measure slaughter performance and muscle quality.The results showed that all three nonlinear models fit well the growth of Wenzhou Red chicken,with a fitting degree(R^(2))reaching over 0.99,among which the Von Bertalanffy model was more suitable for roosters(R^(2)=0.9982),and the Gompertz model was more suitable for hens(R^(2)=0.9973).The dressing percentage reached over 90%,and the whole carcass weight rate reached over 68%.There were no significant differences in half carcass weight rate,whole carcass weight rate,breast muscle rate,leg muscle rate,shear force,water content,crude ash content and crude protein content between rooster and hen,and shear force was increased with the age increasing.The crude fat content of roosters at 30 weeks was the highest and the total calcium content of roosters at 26 weeks was the highest.The total phosphorus content in 26 weeks and 30 weeks old roosters were significantly(P<0.05)higher than that in 34 weeks old ones.The total calcium content and crude fat content in hens at 30 weeks of age were relatively high.In the pectoral muscle,16 amino acids were detected,with hens at 30 weeks of age having higher levels of flavor amino acids than at other ages,while roosters showed a gradual decrease in these amino acids with age;the total unsaturated fatty acids content in the pectoral muscle was higher than that of saturated fatty acids,with the highest unsaturated fatty acids content in hens at 34 weeks and roosters at 30 weeks.At 30 weeks,the profit per rooster was 46.79 yuan,and per hen was 18.73 yuan.In conclusion,it was appropriate for Wenzhou Red chicken hens to be marketed at 30 to 34 weeks of age and roosters at 30 weeks of age.