Dietary resveratrol supplementation improves meat quality of finishing pigs through changing muscle fiber characteristics and antioxidative status

Highlights

• Impact of resveratrol on meat quality of finishing pigs was studied.

• Resveratrol improved pH_24 h and color in m. longissimus dorsi, while decreased shear force and drip loss.

• Resveratrol induced a shift toward more oxidative muscle fibers.

• Resveratrol increased muscle antioxidative capacity.

Abstract

This study investigated the effects of resveratrol (0, 300, 600 mg/kg) on meat quality, muscle fiber characteristics and antioxidative capacity of finishing pigs. The results showed that resveratrol not only increased m. longissimus dorsi (LM) pH_24 h, a*, crude protein and myoglobin content but also decreased L*_24 h, shear force, drip loss, glycolytic potential, as well as backfat depth, LM lactate dehydrogenase activity and mRNA level. Meanwhile, LM total antioxidative capacity, glutathione peroxidase activity and its mRNA level were increased by resveratrol, while malonaldehyde content was decreased. In addition, resveratrol increased myosin heavy chain (MyHC)IIa mRNA level and decreased MyHCIIb mRNA level, along with decreased myofiber cross-sectional area. In conclusion, these results suggest that resveratrol is an effective feed additive to improve pork quality, and the underlying mechanism may be partly due to the changed muscle fiber characteristics and antioxidative capacity induced by resveratrol.

Introduction

As consumer demand for high quality meat is increasing, meat producers should consistently produce and supply meat that is safe, healthy and tasty for consumers to ensure continued development of meat industry. Unfortunately, intensive selection for greater growth rate and lean percentage has led to deterioration in meat quality of pig (Lefaucheur, Ecolan, Plantard, & Gueguen, 2002). However, it is well known that many nutrients have profound impacts on meat quality. Therefore, there is increasing interest in improving pork quality through dietary supplementation with certain nutrients, for example selenium (Zhan, Wang, Zhao, Li, & Xu, 2007), arginine (Ma et al., 2010) and vitamin E (Monahan et al., 1994).

Resveratrol (RES) is known as a natural polyphenol, which is found in various plants, including grape skin, pomegranate and herbal medicines. Numerous studies have investigated its biological activity, which includes antioxidative activities (Baur and Sinclair, 2006, Zhu et al., 2014), life-prolonging effect (Baur et al., 2006), and energy metabolism regulation effect (Lagouge et al., 2006, Timmers et al., 2011). Additionally, RES can induce a muscle fiber type transition toward more oxidative muscle fibers (Lagouge et al., 2006, Price et al., 2012).

It is commonly reported that muscle fiber characteristics (Joo et al., 2013, Kim et al., 2013) and antioxidative capacity (Jiang et al., 2009, Ma et al., 2010, Zhan et al., 2007) are related with many aspects of meat quality that are represented by postmortem (p.m.) pH, water holding capacity, drip loss, meat color, etc. To the best of our knowledge, there was no relevant research that was conducted to test whether RES treatment can change pork quality and, if so, whether muscle fiber characteristics or/and antioxidative capacity can be changed by Res, which may mediate the process. In view of the foregoing, we hypothesized that dietary RES supplementation may change meat quality traits of finishing pigs through influencing muscle antioxidative capacity and/or muscle fiber characteristics. The present study was conducted to test this hypothesis.