Effects of outdoor rearing and potato mixed silage feeding on the behavior, growth, meat quality and muscle fiber characteristics in finishing pigs

To elucidate effects of different rearing environments (indoor rearing vs. outdoor rearing) and diets (commercial diet vs. potato mixed silage) on behavior, growth, meat quality and muscle fiber characteristics in finishing pigs, 32 pigs (WL·D) were divided equally into four groups (2×2 factorial design). Pigs were fattened until the average BW of each group reached 105 kg. Resting behavior was fewer in pigs treated with potato mixed silage and outdoors than those with a commercial diet and indoors (P < 0.01). BW gain during the fattening period was lower in pigs with potato mixed silage and outdoors than in pigs with a commercial diet and indoors (P < 0.01). Outdoor reared pigs had thinner back fat and longer carcass length than those reared indoors (P < 0.01). Loin meat of pigs fed potato mixed silage had significantly higher fat content and lower shear stress than that of pigs fed a commercial diet (P < 0.01). There were no differences in muscle fiber distribution of type-I (slow-twitch) between the groups, but type-IIA (fast-twitch oxidative) showed higher distribution in pigs with potato mixed silage and outdoors than pigs with a commercial diet and indoors. In conclusion, although the outdoor rearing and feeding with potato mixed silage resulted in lower productivity, it was to produce different quality meat and muscle fiber characteristics from the current conventional rearing management system with commercial diet indoors. Therefore, it is suggested that the pig management systems examined in this study could be a way to produce acceptable quality pork to meet consumer needs.