Humans have been breeding domesticated animals for specific characteristics for many years. This process, known as selective breeding, involves humans selecting animals with desirable traits and mating them together to produce offspring with more desirable traits. To achieve genetic progress (also known as genetic improvement and genetic gain), in each generation, only those with the most desirable traits would be allowed to reproduce.
Selective breeding in cattle
Humans have created more than 250 breeds of domestic cattle from a population of common ancestors. Broadly, these can be split into:
- Dairy breeds: selectively bred for milk production (both quantity and quality).
The most common dairy breed in Australia is the Holstein Friesian. Other examples include Jerseys, Brown Swiss, Ayrshire, Illawarra and Aussie Reds. - Beef breeds: selectively bred for meat production.
Broadly, these can be further identified as:- Bos taurus: including British (e.g. Angus, Hereford) or European (e.g. Simmental, Charolais) types. These breeds are typically adapted to temperate environments (e.g. wooly winter coat, cold tolerant).
- Bos indicus breeds (e.g. Brahman). These breeds are typically adapted to tropical environments (e.g. large ears, dewlaps, thin coats, heat and tick tolerant etc).
Key message
Specific characteristics in animals can be achieved through selectively breeding parents, so that progeny are produced with the more desirable characteristics.