Effects of long-term gentle handling on behavioral responses, production performance, and meat quality of pigs

Abstract

In order to investigate the effect of gentle handling on the behavior, performance, and meat quality of pigs from weaning to slaughter, 144 6-week-old weaned hybrid Min piglets (a native breed) were selected and divided into a handling group (HG: 9 pens × 8 pigs) and a control group (CG: 9 pens × 8 pigs). After 6 weeks of handling, we observed and then evaluated the pigs’ responses to a handler with behavioral scores. Moreover, we measured heart rate and production performance. Three pigs were randomly selected from each of the 18 pens and divided into a handling group (HG: n = 27) and a control group (CG: n = 27), and the HG pigs were given gentle handling until slaughter. Subsequently, we evaluated meat quality and the production performance of six pigs from each group. The results show that AA test (approaching–avoidance test) scores in HG pigs, the number of contacts with the handler and absence of contact with the handler, were significantly higher than in the CG pigs (p < 0.01). The occurrences of avoidance and looking at the handler were lower in the HG than in the CG group (p < 0.01); however, heart rate was not found to be significantly different between the two groups (p = 0.63). No significant difference was found in the average daily gain, average daily feed intake, and feed conversion ratio between the two groups during the two periods (p > 0.05). The b* value was determined 45 min after slaughter, and it was significantly lower in the HG than that in the CG group (p = 0.002). Furthermore, 2 h after slaughter, the L value of the HG group was significantly higher than that of the CG group (p = 0.047), but no difference was observed in carcass quality or other meat quality indicators between the two groups (p > 0.05). The results indicate that gentle handling could reduce pigs’ anxiety and increase their willingness to approach the handler, increasing the intimacy of the pigs and handlers. However, long-term gentle handling had little effect on pig performance, carcass quality, and meat quality.