Effect of gender on growth performance, carcass characteristics and meat and fat quality of calves of Avileña-Negra Ibérica breed fattened under free-range conditions

The effect of gender (entire males vs females) on growth performance, carcass traits and meat and fat quality of Avileña-Negra Ibérica calves, fattened under free range conditions and supplemented with concentrate, were investigated. The average daily gain, leg width and thorax depth were higher in males than in females. Carcass conformation score, fore-quarter weight and percentage in carcass were higher in males than in females, whereas dressing percentege, loins and flank percentages in carcass and carcass fatness degree were higher in females than in males. Instrumental colour variables of muscle were not affected by gender at days 1, 3, 7 and 9 of refrigerated storage. In muscle, the L*, a*, b*, chroma, oxymyoglobine and oxymyoglobine/metmyoglobine ratio values observed 9 days after slaughter were lower than those at days 1 and 3 after slaughter. Intramuscular fat percentage of Longissimus thoracis muscle was higher in females than in males. Gender had no effect on α-tocopherol content in intramuscular fat (IMF) from Longissimus thoracis muscle. The omental and IMF of females had lower C18:2 n-6, Σ n-6 and Σ PUFA proportions than those from the males. In IMF C16:1, C18:1 n-9 and Σ MUFA proportions were greater in females than in males. The IMF percentage in Longissimus thoracis affected significantly to its fatty acid composition.