Characteristics of meat and muscle fibers of Nellore cattle finished on feedlot and in pasture

• Grant number: 11/23728-4
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2012
• End date: April 30, 2014
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: Roberto de Oliveira Roça
• Grantee: Roberto de Oliveira Roça
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The meat quality is influenced by factors such as feeding and production system, which are associated with the type of muscle fiber. The objective is to evaluate the effect of food supplementation on pasture linked to the termination in feedlot and pasture on the commercial cuts yield, the meat and skeletal muscle fiber characteristics of Nellore cattle. 96 Nellore no castrated male cattle will be used, at 14 months old and initial live weight of 271 kg, distributed in 4 x 2 factorial scheme, with four supplementation strategies in the rearing period (mineral salt, 0.1% protein, 0.3% protein/energetic and 0.7% energetic of LW) and two finishing systems in the final phase (pasture and confinement). At the end of the experiment, all the animals will be slaughtered when they reach the medium weight of 520kg. Part of the Longissimus dorsi will be collected in order to establish some qualitative parameters of meat such as color, pH, shear force, weight loss by cooking, centesimal composition and fatty acids profile. Samples of the Semitendinosus and Longissimus dorsi will be obtained to analyze the muscle fibers, the fiber morphology will be evaluated and the myosin isoforms of types I and II heavy chain will be quantified by electrophoresis over polyacrylamide gel. The experiment will be carried out in a completely random design in a 4 x 2 factorial. (AU)