Genetic Improvement of Beef Cattle

Abstract

Systems that produce beef are quite heterogeneous, involving different breed types, widely differing environments, a range of market demands and considerable production derived from dairy industries. This contrasts with the pig and poultry industries where there are generally few decision makers, well-directed pursuit of goals and much less variation in production systems, the environment and, in most cases, the market. In major temperate beef-producing countries such as the USA, Canada, parts of South America, New Zealand and parts of Australia, beef production is based on extensively grazed or ranched cows, mainly of pure British beef breeds like the Hereford, Angus and Shorthorn, or crosses of these breeds. In some of these countries, like the USA, Canada and parts of Australia, this extensive pre-weaning regime is usually followed by a more intensive finishing period in feedlots. The extensive nature of many production systems, and the widespread use of crossbred animals in the commercial sector of most beef industries means that performance recording and genetic improvement are usually concentrated in a relatively small sector of the population.