CRC 'Regional Combinations' project — effects of genetics and growth paths on beef production and meat quality: experimental design, methods and measurements.

Abstract

As a component of the second term of the Cooperative Research Centre (CRC) for Cattle and Beef Quality, a project to further test and validate the effects of varying nutritional growth paths pre-finishing and slaughter on cattle of varying genetic potential for meat yield and eating quality was designed and implemented. This project, ‘Regional Combinations’, was a multi-site experiment, using Bos taurus cattle generated at 4 locations across southern Australia. The design of imposing different growth paths between weaning and finishing on cattle with specific genetic potential is common across sites. Treatment and interaction effects on beef production and meat quality were examined within and across sites. This paper describes the experimental designs, generation of experimental cattle at the various sites and the measurements, collection and storage of the data for multi-site analyses.

Performance of steer progeny of sires differing in genetic potential for fatness and meat yield following post-weaning growth at different rates. 1. Growth and live-animal composition

“…Subsequently, the project known as 'Regional Combinations', on which we report here, was conducted to extend the previous findings by examining sire carcass types with potential for more extreme production and carcass characteristics while imposing a variety of regional-specific growth and finishing regimens in beef production systems in different environments across southern Australia. The design for this multisite experiment was described by McKiernan et al (2005). Preliminary results from the various sites have been previously reported by Wilkins et al (2002Wilkins et al ( , 2004, Tudor et al (2004), Graham et al (2005), McKiernan et al (2006) and Irwin et al (2006).…”

“…The overall design and methodology covering all sites in the Regional Combinations project were described by McKiernan et al (2005). Further details specific to our experiment (NSW site) now follow.…”

“…Where possible the sires within each group were also chosen to represent a range of growth EBV (400-day weight). A complete list of the 43 individual sires used here, as well as those at the other Regional Combinations sites, was given by McKiernan et al (2005). Many of the sires were used across sites to provide the genetic links for combining sites in an analysis to be reported in a later paper.…”

Effects of growth path, sire type, calving time and sex on growth and carcass characteristics of beef cattle in the agricultural area of Western Australia

“…The details of the progeny and the production systems from both the autumn (AC, March-April) or winter (WC, June-July) calving cows has been described by Read et al (2004) and McKiernan et al (2005). Approximately equal numbers of weaned steers and heifers from each of the AC and WC progeny groups were selected for raising to a liveweight suitable for the Western Australian domestic market at Vasse Research Station (115.24E, 33.43S) over 3 years .…”

Comparação entre medidas ultra-sônicas e da carcaça na predição da composição corporal em bovinos: estimativas do peso e da porcentagem dos cortes comerciais do traseiro

“…Segundo McKiernan et al (2005), o rendimento dos cortes desossados constitui um importante componente no desenho de modelos de programas de melhoramento genético para mérito de carcaça de bovinos. Segundo Hamlin et al (1995), a variação nas características biológicas economicamente importantes é grande e está sob alto grau de controle genético.…”