Effect of genotype and dietary protein level on lamb meat quality

Abstract

This study aimed to evaluate the lamb meat quality of Santa Ines and Dorper x Santa Ines lambs fed 12 or 20% dietary crude protein (CP) level. Twenty four animals were used, with initial weight of 17 ± 1,82kg, individually penned, fed 40% of corn silage and 60% of concentrate and slaughtered at 35 kg of body weight. After carcass cooling, a sample of Longissimus dorsi was removed to determine the chemical composition and the meat quality characteristics. There was no effect for moisture (71,74%), protein (21,43%) and minerals (1,08%), however, Santa Ines lambs showed higher fat content in meat in relation to cross Dorper x Santa Ines when fed 20% of CP (4,43%). The genotype and crude protein level of diet did not affect pH (5,65), cholesterol (28,28mg/100g of meat), water activity (1,002), color (L*: 41,20; a*: 15,62; b*: 5,09), cooking weight loss (35,98%), shear force (1,10kgf/cm2) and water holding capacity of meat (60,18%). The meat of crossbred lambs Dorper x Santa Ines showed less fat when fed 12 and 20% of dietary crude protein and could constitute a marketing tool to promote the meat from this cross. Protein levels evaluated did not affect the quality characteristics of lamb meat, being able to use the lowest level (12%), aiming the formulation of economic diets for producer, since that it also allows satisfactory animal performance.