ANTEMORTEM HANDLING EFFECTS ON THE BEHAVIOR, CARCASS YIELD AND MEAT QUALITY OF MARKET WEIGHT ENTIRE MALE PIGS

The effect of antemortem handling on behaviour, carcass yield and lean meat quality was determined on Lacombe and Yorkshire entire male pigs mixed within breed 24 h prior to slaughter and on entire males and gilts that were not mixed. In the period immediately after repenning (mixing), 40% of all recorded pen activity was observed, while 17% and 10% of the pen activities were recorded at 6 and 12 h after repenning. During the period immediately after transport to the abattoir, 33% of all pen activities were observed. Mixed pigs accounted for 78% of all activity. Yorkshire male pigs were three times as active as Lacombe male pigs during shipping. Thirty-six percent and 14% of the mixed Yorkshire and Lacombe male pigs had moderate skin blemishes, compared with 12% for unmixed Yorkshire male pigs. Moderate skin blemishes were absent in the unmixed Lacombe male and all female pigs. Dressing percentage and carcass shrinkage were unaffected by mixing during shipping. Dressing percentage was 23 g kg higher in female than in male pigs, while male pigs had 20 g kg(-1) greater lean than female pigs. Ultimate pH (48 h) was similar among unmixed pigs (5.53), but higher in mixed Lacombe (5.61) and Yorkshire (5.74) entire male pigs. Based on subjective meat quality evaluation, firm and dry pork was observed in 11% and 43% of the mixed Lacombe and Yorkshire male pigs, but was absent in unmixed male pigs. However, no consistent objective meat quality differences between unmixed male and female pigs were observed. Unmixed entire male pigs had superior carcass composition characteristics, with lean meat quality attributes at least equivalent to those of female pigs (e.g. pH, drip loss, CIE L*, hue angle). Mixing entire male pigs prior to slaughter had marginal but significant effects on carcass blemish scores and meat quality, particularly among Yorkshire pigs. This study suggests entire males, with appropriate antemortem handling, can produce superior carcasses, more efficiently and with pork quality at least equivalent to that of female pigs.