ChileanJAR

The effect of sex performance in growing-finishing pigs was analysed. Productive measurements, as average daily gain, food intake, feed efficiency, carcass lenght, loin lenght, backfat and carcass yield, were compared in 144 crossbred pigs (Hipor x Landrace x Large White), distributed in four treatments and three replications. The treatments were: Castrated males and gilts (control); Intact males; Castrated males; and Gilts. The experimental diets were adjusted to recommendations and the animals were fed ad libitum. Sex constituted a significant source of variation for the mayority of the measurements made. Average daily gains were significantly higher, during finishing period, in males (castrated or boars) than the control and the gilts (P<0.05). Intact males had less feed consumption than the other treatments (P<0.01) and also were 13% more efficient in feed conversion than the castrated (P<0.0001). Carcass and loin lenghts were not different among the experimental groups; but there was a significant difference in the averages of backfat. The intact males and the gilts presented the lower values (3.03y; 2.45z; 32.7x and 2.99y, respectively) (P<0.0001). On the other hand, intact males has the lowest arcass yield (P<0.0001). It was concluded that the pork producing systems with intact males are beneficial, in terms of the productive efficiency but also in carcass characteristics.