Jiang M, Fan W L, Xing S Y, Wang J, Li P, Liu R R, Li Q H, Zheng M Q, Cui H X, Wen J, Zhao G P
Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, P. R. China.
State Key Laboratory of Animal Nutrition, Beijing 100193, P. R. China.
Poult Sci. 2017 Feb 1;96(2):282-287. doi: 10.3382/ps/pew334. Epub 2016 Oct 24.
Intramuscular fat (IMF) content contributes to meat flavor and improves meat quality. Excessive abdominal fat, however, leads to a waste of feed resources. Here, an independent up-selection for IMF was used as a control (Line C), and a balanced selection program, with up-selection for IMF and down-selection AFP (Line B), was studied in JingXing yellow chickens. The mean of IMF and AFP within a family was the phenotypic value upon which selection was based. The selective pressures of IMF in line B and line C were the same in each generation. At G5, the IMF was significantly higher (P < 0.05) than that at G0 in both lines. For AFP, Line C was significantly higher at G5 (P < 0.05) than at G0, but the difference in Line B was not significant (P > 0.05). IMF increased by 11.4% and AFP decreased by 1.5% in Line B compared with the G0 generation. In contrast, the IMF increased by 17.6%, but was accompanied by an 18.7% increase in AFP, in control Line C. Of 10 other traits measured, body weight at 56 d age (BW56) and the percentages of eviscerated weight (EWP) showed a significant difference between the 2 lines (P < 0.05). The heritabilities for IMF and AFP, estimated by the DMU package, were 0.16 and 0.32, respectively. A moderate positive correlation existed between IMF and AFP (0.35). A balanced selection program for increasing IMF while controlling AFP (Line B) is shown here to be effective in practical chicken breeding.
肌内脂肪（IMF）含量有助于提升肉的风味并改善肉质。然而，过多的腹部脂肪会导致饲料资源的浪费。在此，以对IMF进行独立向上选择作为对照（C系），并在京星黄鸡中研究了一种平衡选择方案，即对IMF进行向上选择同时对腹脂（AFP）进行向下选择（B系）。一个家系内IMF和AFP的均值作为选择所依据的表型值。B系和C系中IMF的选择压力在每一代都是相同的。在第5代时，两系的IMF均显著高于第0代（P < 0.05）。对于AFP，C系在第5代时显著高于第0代（P < 0.05），但B系的差异不显著（P > 0.05）。与第0代相比，B系的IMF增加了11.4%，AFP降低了1.5%。相比之下，对照C系中IMF增加了17.6%，但AFP也随之增加了18.7%。在所测量的其他10个性状中，56日龄体重（BW56）和屠体重百分比（EWP）在两系之间存在显著差异（P < 0.05）。通过DMU软件包估计，IMF和AFP的遗传力分别为0.16和0.32。IMF和AFP之间存在中等程度的正相关（0.35）。本文表明，在控制AFP的同时增加IMF的平衡选择方案（B系）在实际的鸡育种中是有效的。
