National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Guangdong Wen's Nanfang Poultry Breeding Co. Ltd, Yunfu 527400, Guangdong Province, China.
Poult Sci. 2018 Jul 1;97(7):2356-2364. doi: 10.3382/ps/pey062.
Feed consumption accounts for the major cost of broiler production. Improving the efficiency of feed utilization is a primary goal in breeding strategies, although few studies have focused on slower growing broilers. Here, we recorded the feed intake (FI) during the fast-growing period (d 56 to 76) and measured the live weight, body measurements, carcass characteristics, and intramuscular fat (IMF) content of Chinese yellow broilers. Then, the residual feed intake (RFI) and feed conversion ratio (FCR) were calculated for each individual. Pair-wise phenotypic correlations were subsequently calculated between feed efficiency traits and others. Finally, we separately selected the more efficient individuals based on RFI and FCR values to evaluate the impacts on the traits of FI, growth, carcass characteristics, and meat quality. The results showed higher correlations between FCR and production traits than with RFI, while RFI showed a moderate and positive phenotypic correlation with abdominal fat. FCR was weakly correlated with FI and slightly positively correlated with IMF content. The correlation coefficient between RFI and FI was 0.62, and that between RFI and IMF content was close to zero. Without increasing FI, decreasing FCR could effectively enhance the growth rate and market weight with no adverse effect on meat quality. In contrast, by improving RFI, FI and abdominal fat mass were significantly reduced and thus increased the yield with no unfavorable effects on meat quality. In consideration of consumer preference and overall economical benefits, RFI is a more suitable index to improve feed efficiency in slower growing broilers.
饲料消耗是肉鸡生产的主要成本。提高饲料利用效率是育种策略的主要目标，但很少有研究关注生长较慢的肉鸡。在这里，我们记录了中国黄羽肉鸡快速生长期（第 56 天至 76 天）的采食量（FI），并测量了活重、体尺、胴体特征和肌内脂肪（IMF）含量。然后，计算了每个个体的剩余采食量（RFI）和饲料转化率（FCR）。随后，对饲料效率性状与其他性状之间的表型相关性进行了两两计算。最后，我们根据 RFI 和 FCR 值分别选择了更有效的个体，以评估其对 FI、生长、胴体特征和肉质性状的影响。结果表明，FCR 与生产性状的相关性高于 RFI，而 RFI 与腹部脂肪呈中度正相关。FCR 与 FI 呈弱相关，与 IMF 含量呈轻微正相关。RFI 与 FI 的相关系数为 0.62，与 IMF 含量的相关系数接近零。不增加 FI，降低 FCR 可以有效提高生长速度和上市体重，而对肉质没有不利影响。相比之下，通过提高 RFI，可以显著降低 FI 和腹部脂肪量，从而提高产肉率，而对肉质没有不利影响。考虑到消费者偏好和整体经济效益，RFI 是提高生长较慢肉鸡饲料效率的更合适指标。
