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Cold Winter Climates
encompasses both the physical environment for example, prevailing climate, soils, forage species and
the management environment for example, timing of breeding cycle, supplementary nutrition, health,
husbandry practices. In contrast to the long-term nature of genetic change, management decisions afecting
the animal or herd’s current environment can have an immediate impact on productivity.
A sound understanding of the actions available to beef managers to address any preventable environmental
limitations is therefore essential in challenging environments such as the cold winter climates of the
northern hemisphere.
Inherent genetic traits and the overall living environment ultimately interact in very complex ways to determine
the physical appearance and production of beef cattle. A successful beef breeding enterprise must understand,
and where possible inluence these interactions in order to produce their ‘ideal’ animal.
5.2. The Role of Genetics
Genetics afect the ability of the beef enterprise to achieve its deined production goals. For breeding enterprises,
important production traits are fertility, calving ease and milk supply. For steer production, important production
traits include growth rate, muscling and carcase quality. As little genetic information is available for most
commercial females, it is through the selection and use of appropriate bulls that most deliberate genetic gain is
made in a breeding herd.
Over its working life, a single sire has a much greater inluence than a single cow on the rate of herd genetic
improvement. For example a cow might produce 7 to 9 calves in her lifetime while a bull may produce more
than 100 calves over his life.
An important consideration when selecting sires for use in a breeding program is that introduced bulls or semen
be unrelated, or very distantly related, to current and previously used sires in the herd.
Inbreeding can lead to reduced animal performance and an increased susceptibility to some genetic
disorders. This is most likely to occur with widespread and continued use of a limited number of sires in an
artiicial insemination program. This situation is not uncommon in central Asia, and enterprises importing
Australian heifers will need to ensure they use sires that provide genetic diversity to the herd as the herd age
structure matures.
5.2.1. Selecting the Most Appropriate Breed
Many beef cattle breeds exist throughout the world, each with particular characteristics that make it successful in
its place of origin. While considerable genetic diversity exists within all breeds, the general characteristics of each
breed as a whole provide a base for determining what breed or combination of breeds might be best suited
to any individual enterprise. Put simply, the environment the animals live in and the market to be supplied are
the major determinants of the most appropriate breed of cattle to use. The basic characteristics of the most
common beef breeds are: • British breed cattle e.g. Angus, Hereford, Shorthorn
are best adapted to temperate, Mediterranean and Continental environments, and are early maturing,
perform well on moderate nutrition, have high fertility and good eating quality carcases
• European breeds e.g. Charolais, Limousin, beef Simmental grow faster, have more muscle and
mature at a later age. They require more feed than British breeds to lay down adequate fat
• Bos indicus breeds e.g. Brahman, Santa Gertrudis are best adapted to tropical environments, and have
high survivability under poor nutrition, and excellent parasite resistance
• Dairy breeds e.g. Holstein, dairy Simmental can be crossbred with British breeds to produce specialist
vealer producing cows and these require good nutrition to achieve their production potential
• Composite breeds are a combination of two or more breeds bred together until they reach a stable
biological type. The breeds used will determine the biological type, its potential productivity, and
nutritional requirements to achieve it • Crossbreeding within a herd can make better use of
breed selection by combining breeds with diferent strengths e.g. fertility of British breeds combined
with muscling and growth of European breeds or with the environmental adaptation of local breeds.
The progeny from these animals will also exhibit hybrid vigour, signiicantly lifting performance
further.
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Beef Breeder MANUAL
Most young beef heifers imported from Australia to cold climate countries will be British breeds. These breeds
are well adapted to the central Asian climate, produce high eating quality beef, and there is a large international
herd from which to select pedigree animals. Imported heifers will most likely form the foundation of purebred
herds, but some may become part of a crossbreeding program with local breeds commonly dual-purpose
dairy and beef animals.
5.2.2. Crossbreeding
