Relationship between carcass traits, prime cuts and carcass grading from foals slaughtered at the age of 13 and 26 months and supplemented with standard and linseed-rich feed.

In order to improve foal carcass quality, it is necessary in particular to improve the carcass dressing percentage and tissue composition. Thus, it is important to establish relationships between grading systems and these parameters. This research was conducted to study the effect of slaughter age (13 v. 26 months) and finishing feed (standard v. linseed feed) on carcass characteristics such as subcutaneous fat colour plus classification of foals for the degree of fatness and conformation. For this study, 46 foals of crossbred genotype (Galician Mountain×Burguete) were used. Finishing feed did not affect any parameter, whereas slaughter age influenced all parameters (P<0.05). The oldest foals had higher carcass measurements, 13% more of meat, 4% more of bone, 12% more of fat, and 4% and 9% bigger fore- and hindquarter, respectively. Consequently, bigger valuable prime cuts were obtained. Nevertheless, the meat : bone ratio was very similar for both 13- and 26-month-old foals (2.88). Most of 26-month-old foals were classified in 'E' (Extra) and '5' (Complete fat cover) categories of conformation and degree of fatness. Most of the carcasses showed subcutaneous fat described as yellowish-white irrespective of age or diet. A regression model found that conformation (36%) and degree of fatness (33%) in live animals was positively linked with carcass tissue composition. It is therefore suggested that producers aim for older slaughter ages than 13 months and that the foal meat industry establishes grading systems to predict carcass quality. Further studies should be necessary to find the optimal slaughter age to obtain carcasses in the best categories of degree of fatness and conformation. New studies should be recommended to improve the meat : bone ratio of foal carcasses as it estimates the aptitude for meat production.