Estimation of Genetic Parameters for Contents of Intramuscular Fat and Inosine-5′-Monophosphate and Carcass Traits in Chinese Beijing-You Chickens

Abstract

This study was conducted to estimate genetic parameters of meat quality-related traits by a MTDFREML procedure, using 1,069 purebred Beijing-You full-sib male chickens derived from the first 2 generations of divergent selection for the percentage of intramuscular fat (IMF) and selection for increased inosine-5'-monophosphate content (IMP) in breast meat. The results show that estimated heritability of IMP was moderate (0.23), and heritability of IMF was low (0.11). Other traits with high heritabilities, ranging between 0.56 and 0.79, were BW, abdominal fat weight (AFW), breast meat yield, ratio of breast meat yield to evisceration weight (BMP), leg muscle yield, comb weight, and ratio of comb weight to BW (CWP). Moderate heritabilities for the ratio of AFW to BW (AFP) and leg muscle yield to evisceration weight were estimated, 0.24 and 0.32, respectively. Lower significant phenotypic correlations of IMP with BMP and ratio of leg muscle weight to evisceration weight were discovered (P < 0.05), whereas IMF exhibited slightly positive, though significant, phenotypic correlations with BW (0.11) and AFP (0.27). Genetic correlations of IMP with BW and CWP were negative (-0.38 and -0.62, respectively), whereas a high positive genetic correlation was found between IMP and BMP (0.57). It was found that IMF had high genetic correlations with BW (0.75) and AFW (0.66) and moderate correlations with AFP (0.32) and CWP (0.40). A low positive genetic correlation was estimated between IMP and IMF (0.27). In conclusion, both IMP and IMF contents in chicken meat have the potential to be increased through genetic selection with little or no positive effect on BW. Furthermore, close managerial control of growth rate (and BW) will be needed to assure high quality of chicken meat so that increased IMP and IMF can be obtained with less abdominal fat deposited.

Estimates of genetic parameters and cluster analyses for carcass and meat quality traits in birds

“…The heritability estimate for AF (0.80±0.08) was also high, indicating that this trait can respond very well to selection. Chen et al (2008) worked with Beijing-You birds and obtained a heritability estimate of 0.62, close to those reported in the present study, whereas Lotfi et al (2011), while studying quails, found heritability estimates of 0.28±0.06 for AF, different from those obtained here.…”

Analysis of a slow-growing line reveals wide genetic variability of carcass and meat quality-related traits

“…According to our results, selection for decreasing carcass fatness by reducing AFP should not lead to any significant change in IMF, which is known to influence sensorial characteristics of the meat such as juiciness and flavour [7]. Similarly, the studies by Chen et al [17] and Zerehdaran et al [15] failed to demonstrate any significant correlation between the deposition of abdominal fat and that of intramuscular fat in breast muscle, whereas a positive genetic correlation was reported between abdominal and subcutaneous fat. On the other hand, our results indicated that selection for lower carcass fatness should increase the intensity of the red and yellow colour of breast meat, especially in males in which a strong genetic link between AFP and body weight was also found.…”

Comparison of carcass and meat quality traits between lean and fat Pekin ducks

“…However, since IMP content is greatly influenced by nutrition, breeds, and storage time, more work should be performed from both of those selection aspects. The limited number of studies about the heritability of IMP in chicken and other species showed that IMP has low heritability [22]. In the experimental population, the IMP content showed a large coefficient of variance (12.7% and 17.6%), indicating that IMP had a possibility for improvement.…”