Gestational nutrient restriction under extensive grazing conditions: Effects on muscle characteristics and meat quality in heavy lambs.

We evaluated maternal undernutrition effects induced by a lower natural pasture allowance (gestation days 30-143) on histological-biochemical and meat traits in muscles Semitendinosus, cranial Gluteobiceps and Supraspinatus from 200-day old male and female lambs. Maternal undernutrition increased oxidative and reduced glycolytic fibers in all muscles (P ≤ 0.01). Maternal undernutrition reduced the diameter of glycolytic fibers in the cranial Gluteobiceps of exclusively female lambs (P = 0.05) and reduced the diameter of oxidative fibers in the Supraspinatus of exclusively male lambs (P = 0.02). Maternal undernutrition increased lipid content in the Supraspinatus of females (P = 0.001), reduced lactate content (P = 0.03) and WB shear force (P = 0.02) in the Semitendinosus of females, and increased cooking losses in the Semitendinosus of males (P = 0.0069). In conclusion, gestational nutrient restriction induced fetal programming effects on muscle characteristics of lambs. Moreover, our study demonstrates that maternal undernutrition influences muscle and meat characteristics in a sex and muscle-dependent way.