EFFETS DES METHODES DE RATIONNEMENT SUR LES PERFORMANCES ET LA QUALITE DES CARCASSES DES PORCS DE MARCHE

Abstract

Growth, feed efficiency, and carcass data were obtained on ninety-four (94) crossbred pigs, to study the effect of types of feed restriction. The feeding treatments used in this experiment were as follows: (1) ad libitum; (2) 30–45 min per meal twice a day; (3) restricted to 85% of treatment 1, but with a 15% increase in protein, vitamin, and mineral supplementation; the pigs were started on this treatment at 27 kg of body weight; (4) same as treatment 3, but starting at 57 kg of body weight; (5) fasting once a week, starting at 27 kg of body weight; (6) same as treatment 5, but starting at 57 kg of body weight. During the rest of the week, pigs on treatments 5 and 6 were fed as on treatment 2. The pigs fed ad libitum were superior (P = 0.05) in growth rate and feed efficiency to those on a restricted diet. Those which fasted once a week starting at a body weight of 27 kg were significantly inferior (P = 0.05) to those on the other treatments. Backfat thickness and loin length were increased (P = 0.05) by the ad libitum feeding treatment, whereas carcass length and weight, ham weight, and rib eye area were not significantly affected (P = 0.05) by the feeding systems. Castrated males were superior (P = 0.05) to females in growth and inferior (P = 0.05) in carcass quality. The females had longer carcasses, leaner hams, and larger rib eye areas (P = 0.05) than the males. Crossbred Poland China × Yorkshire–Lacombe (P × Y–Lc) had heavier and fatter carcasses (P = 0.05) than crossbred Poland China × Yorkshire–Landrace (P × Y–Ld). However, rib eye area and dressing percentage were superior (P = 0.05) for the P × Y–Lc cross.