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Effect of feed texture, meal frequency and pre-slaughter fasting on carcass and meat quality, and urinary cortisol in pigs.

Agriculture and Agri-Food Canada, Dairy and Swine Research and Development Centre, P.O. Box 90, 2000 College Street, Sherbrooke, Que., Canada J1M 1Z3.
Meat Science (Impact Factor: 2.23). 12/2006; 74(4):697-703. DOI: 10.1016/j.meatsci.2006.05.023
Source: PubMed

ABSTRACT Carcass and meat quality traits, and urinary cortisol variation was studied in 96 barrows assigned to the following treatments: feed texture (FT; mash vs. pellets), meal frequency (MF; 2 vs. 5 meals per day) and fasting time (F; 4, 14 and 24h) according to a 2×2×3 factorial design. Pigs fed mash, receiving feed five times a day and fasted for 24h before slaughter had lower carcass dressing yield (P<0.001). A higher (P<0.05) bruise score was found on carcasses from pigs fasted for 14 and 24h and fed either pelleted or mashed feed five times per day. The pH(u) value in the Longissimus muscle increased (P<0.05) with increasing fasting time, whereas in the Adductor muscle it was higher (P<0.05) in pigs fed with pellets in two meals per day and fasted for 24h. Urinary cortisol tended to be higher in pigs fasted for 14h compared to those fasted for 4 (P=0.10) and 24h (P=0.06). The results of this study show a significant influence of pellet feeding on carcass yield in fasted pigs, while the effects of pre-slaughter fasting time on meat quality traits were limited.

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