Evaluation of biochemical parameters and genetic markers for association with meat tenderness in South African feedlot cattle
Agricultural Research Council of South Africa, Private Bag X2, Irene, 0062, South Africa; Department of Animal and Wildlife Science, University of Pretoria, South Africa; US Meat Animal Research Centre, ARS, USDA, P.O. Box 166, Spur 18-D, NE 68933-0166, United States; IEH Laboratories, Consulting Group, 15300 Bothell Way NE, Lake Forest Pk., WA 98155, United States
A large proportion of South African feedlot cattle are crossbreds of Brahman (BrX, Bos indicus), and Simmental (SiX, Bos taurus). A sample of 20 grain fed bulls from each of these crossbreeds was used to compare meat quality with that of the small frame indigenous Nguni (NgX, Sanga) by evaluating a variety of biochemical and genetic parameters previously shown to be associated with meat tenderness. Shear force values were generally high (5.6 kg average at 14 days post mortem), with SiX animals higher than BrX or NgX (P = 0.051) despite higher calpastatin:calpain ratio in BrX (P < 0.05). Calpain activity and cold shortening were both correlated with tenderness for all classes. The sample size was too small to accurately estimate genotypic effects of previously published markers in the CAST and CAPN1 genes, but the allele frequencies suggest that only modest progress would be possible in these South African crossbreds using these markers. © 2009 Elsevier Ltd.
Animalia; Bos; Bos indicus; Bos taurus; Sanga