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Why Performance Test? Understanding BreedPlan How to use EBV’s
Why Performance Test?
Performance testing has been incorporated into
the breeding program at Cudgegong Park through the Murray Grey Group Breedplan, with emphasis being placed on the genetic characteristics that produce efficient cattle.
Reproduction
is a complex trait that has more influence on profitability than any other factor. Cows which fail to conceive over a restricted joining period or to calve satisfactorily are ruthlessly assessed, and culled. Early growth of the calf is directly related to the
milking ability
of the dam. A cow’s relative mothering ability is revealed on weighing her calf at approximately 7 months (200 days) and adjusting this weight to account for her age and the age of the calf. Assessing the production efficiency of this cow requires a compromise between her mature weight, milking ability and fertility.
Throughout the nest year the
cattle are on their post weaning test (to 400 days). The Ability of a beast to gain rapidly is highly heritable and has strong bearing on its efficiency in converting grass into beef. These yearling bulls and
heifers are raised on pastures, without supplementary feeding to ensure that they are selected for conversion efficiency, not appetite - as would be the case on a full feed diet. An animal that grows faster than its
mates expends a lower proportion of its food intake maintaining itself and more is available for muscle development. At the end of this test period, approximately 18 months (600 days), all stock are weighed,
measured and visually assessed for breed type, structural soundness and confirmation.
A bull’s fertility
during paddock mating can be assessed by measuring serving capacity, testicle size, and at approximately 18 months (600 days).
Serving capacity is an excellent indication of
sexual indication during paddock mating. Those bulls with low scores are not offered for sale. High pregnancy rates are attributed to the use of bulls with large testicles, s scrotal size is directly related to
daily sperm production. Bulls with scrotal circumferences less than 33cms at 18 months are culled. semen quality can be determined by manual palpation of the testes. Firm springy testes produce good quality semen,
while soft spongy testes tend to be undesirable and low producers of semen.
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