Effect of long term supplementation with Lippia spp. extract on meat quality parameters in heavy pigs

In the recent year, considerable attention has been focused on the improvement of meat quality parameters. The general trend towards the reduction of synthetic substances since the restriction in 2006 of the use of antibiotic has increased the interest in studying natural substances. The aim of the study was to investigate the effects of long term dietary supplementation in pig with plant extract (PE) from Lippia spp., titrated in verbascoside (5 mg/kg feed), from weaning to slaughter on growth performances, nutritional profile and meat quality parameters. Eighteen pigs of initial live weight (LW) of 23.6 kg were assigned to two experimental groups: the first fed a basal diet (CON) and the second one fed a basal diet supplemented with hydroalcoholic plant extract (PE) from Lippia spp. for 7 months. At slaughter (169.8 kg LW), the Longissimus dorsi (LD) muscle was sampled from all pigs (N = 18), vacuum packaged and stored at – 20 °C for 14 days until physical and chemical analyses. The data were analysed by one way Analysis of Variance (ANOVA) using SPSS (IBM - SSPS Statistics 24). Dietary supplementation with PE did not affect growth performance, carcass traits, colour and pH of LD. Muscle drip loss was slightly higher (P=0.068) in CON group than in pigs fed with PE (3.42% vs 2.93%, respectively). In addition, the total losses was lower (P<0.05) in LD muscle from pigs fed PE than controls (17.82% vs 19.2%, respectively). Dietary PE supplementation decreased (P< 0.05) cholesterol content of meat (57.8 mg/100g vs 51.0 mg/100g). Dietary PE was not able to influence intramuscular collagen amount and hydroxylysylpyridinoline (HLP) concentration but the collagen stability (moles of HLP/mole of collagen) resulted higher (P< 0.05) in LD from pigs fed PE than controls (0.167 mol/mol vs 0.132 mol/mol respectively). The present data showed that dietary supplementation with Lippia spp. is able to improve both technological and nutritional quality of LD muscle. This dietary supplementation is able to enhance nutritional quality of pork, decreasing the cholesterol content. Future studies are required to clarify the optimal length and dosage of dietary supplementation in heavy pigs in order to verify the plant extract efficacy in dry cured products.