Meat quality of lambs fed phytogenic additives1

Abstract

The study was developed in the Sheep Production Laboratory of the Department of Animal Science, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, SP, Brazil. Thirty-two non-castrated Ile de France lambs weighing 20.0 ± 0.2 kg received 4 diets with a roughage: concentrate ratio of 40: 60. The experimental treatments consisted of D1: corn silage + concentrate; D2: corn silage + concentrate + 30 mg rosemary extract kg body weight1; D3: corn silage + concentrate + 30 mg green tea extract kg body weight-1; and D4: corn silage + concentrate + 30 mg oregano extract kg body weight-1, up to 35.0 ± 0.2 kg body weight. The objectives were to evaluate rib eye area, cholesterol content, lipid oxidation, qualitative parameters, as well as perform sensory analysis, centesimal composition, and fatty acid profile of the meat. The experimental design was completely randomized with four treatments and eight replicates. The treatments were compared by Tukey’s test through the SAS software (Statistical Analysis System Institute [SAS], 2003). Inclusion of phytogenic additives into the diets did not affect the qualitative parameters cholesterol content, lipid oxidation, and centesimal composition (except for protein content, which was lower in D2, 22.57%, compared to D1, 25.62%), as well as meat fatty acid profile (except for C18: 1n7 cis-vaccenic). The use of phytogenic additives provided suitable qualitative parameters. Moreover, despite the well-known positive effect of antioxidants in the diet, phytogenic additive inclusion was ineffective in reducing lipid oxidation in lamb meat. However, further studies with different inclusion percentages should be carried out to find out how to increase shelf life without harming lamb qualitative parameters, especially regarding the sensory analysis.