Impact of Heat Stress on Meat Quality and Antioxidant Markers in Iberian Pigs

Heat stress is associated with impaired meat quality and disruption of redox balance. This study investigated the effect of chronic exposure to high temperature on meat quality and antioxidant markers of muscles (longissimus lumborum and gluteus medius) of growing Iberian pigs. Twenty-four pure Iberian pigs were allocated during 28 days to one of three treatments (n = 8/treatment): thermoneutral conditions (20 degrees C) and ad libitum feeding (TN), heat stress conditions (30 degrees C) and ad libitum feeding (HS) and thermoneutral and pair-fed with HS (TN-pf). Muscles of the HS group had greater intramuscular fat content than the TN-pf group and higher Zn levels than TN and TN-pf, whereas differences on fatty acid composition were negligible. Heat exposure did not affect pH, color coordinates of redness (a*) and yellowness (b*) and MDA values but had a positive influence on lightness and drip losses. Moreover, chronic heat stress stimulated the activity of antioxidant defenses SOD, CAT and GPx. The statistical factor analysis adequately classified the muscles studied, but was unable to differentiate samples according with treatments. Findings of the present study support an adaptive response of the Iberian pig to high temperatures and show the high Iberian meat quality even under adverse climate situations.

Automated summary

This study investigated the effects of chronic exposure to high temperature on meat quality and antioxidant markers of muscles in growing Iberian pigs. The results showed that heat exposure had significant impacts on intramuscular fat content, zinc levels, and antioxidant enzyme activities, while pH, color coordinates, and fatty acid composition were not significantly affected. The findings suggest an adaptive response of Iberian pigs to high temperatures and highlight the high meat quality of Iberian pigs even under adverse climate conditions.