The fat content and fatty acid composition of porcine meat and carcass influence nutritional value of meat and various techno- logical aspects of meat and carcass quality. Variation in lipid composition has an important effect on firmness of the fat in meat, especially the subcutaneous and intermuscular (carcass fats) but also the intramuscular (marbling) fat. Moreover, as a major source of energy and as structural components of mem- branes, fatty acids are essential for life. The aim of the study was to estimate genetic parameters for backfat fatty acid composition (FAC) and intramuscular fat content (IMF) of semimembranosus muscle in a sample of 949 Sib-tested Italian Large White pigs. Backfat tissue and semimembranosus muscle tissue samples were collected at slaughter and stored at -80°C. IMF content and backfat FAC were determined by gas chromatography and analy- sis of the fatty acid methyl esters. Heritability (h2) and genetic correlations between subcutaneous fatty acids composition and carcass and meat quality traits were estimated using the restrict- ed maximum likelihood methodology applied to a multiple-trait Animal Model. The model was: Yijklm = μ + sexi + dj + b1ak + animall + eijklm where Y = analysed traits; μ = general mean; sex = fixed effect of sex; d = fixed effect of slaugher day; b1 = regression coefficient of the fixed effect of age at slaughtering (ak); animal = random additive effect of each animal; eijklm = error of the model. Results showed that the estimate of h2 for FAC were of moderate magnitude. This study suggest that back- fat FAC is genetically correlated with carcass quality traits and the selection for carcass and meat quality traits produces a cor- related response on FAC of subcutaneous fat. The reduction in fat covering tissue is associated with an increase of lipid insatu- ration and a decrease in subcutaneous fat firmness that deter- mines technological problems in dry cured ham quality. Very low genetic correlations were found between IMF content and back- fat fatty acids. The results found suggest the possibility of genet- ic improvement of FAC of subcutaneous fat by a partial substitu- tion of saturated fatty acids with monounsaturated ones. This would not hinder the technological characteristics of hams for seasoning while improving its eating quality.
Study on genetic parameters of subcutaneous fatty acid composition in Italian Large White pig breed
MELE, MARCELLO;SERRA, ANDREA;
2015-01-01
Abstract
The fat content and fatty acid composition of porcine meat and carcass influence nutritional value of meat and various techno- logical aspects of meat and carcass quality. Variation in lipid composition has an important effect on firmness of the fat in meat, especially the subcutaneous and intermuscular (carcass fats) but also the intramuscular (marbling) fat. Moreover, as a major source of energy and as structural components of mem- branes, fatty acids are essential for life. The aim of the study was to estimate genetic parameters for backfat fatty acid composition (FAC) and intramuscular fat content (IMF) of semimembranosus muscle in a sample of 949 Sib-tested Italian Large White pigs. Backfat tissue and semimembranosus muscle tissue samples were collected at slaughter and stored at -80°C. IMF content and backfat FAC were determined by gas chromatography and analy- sis of the fatty acid methyl esters. Heritability (h2) and genetic correlations between subcutaneous fatty acids composition and carcass and meat quality traits were estimated using the restrict- ed maximum likelihood methodology applied to a multiple-trait Animal Model. The model was: Yijklm = μ + sexi + dj + b1ak + animall + eijklm where Y = analysed traits; μ = general mean; sex = fixed effect of sex; d = fixed effect of slaugher day; b1 = regression coefficient of the fixed effect of age at slaughtering (ak); animal = random additive effect of each animal; eijklm = error of the model. Results showed that the estimate of h2 for FAC were of moderate magnitude. This study suggest that back- fat FAC is genetically correlated with carcass quality traits and the selection for carcass and meat quality traits produces a cor- related response on FAC of subcutaneous fat. The reduction in fat covering tissue is associated with an increase of lipid insatu- ration and a decrease in subcutaneous fat firmness that deter- mines technological problems in dry cured ham quality. Very low genetic correlations were found between IMF content and back- fat fatty acids. The results found suggest the possibility of genet- ic improvement of FAC of subcutaneous fat by a partial substitu- tion of saturated fatty acids with monounsaturated ones. This would not hinder the technological characteristics of hams for seasoning while improving its eating quality.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
