Genetic Variation in Adaptive Traits of Cattle in North Australia

Adaptation to environmental stressors is of particular importance for cattle breeders in tropical regions of northern Australia. Various studies have estimated the genetic parameters for adaptive traits measured in northern Australian cattle herds, but most were specific to regions and breeds. The current study assesses adaptability measures of both Brahman and Composite cattle (n=2071) raised in four distinct environments of northern Australia. Heritabilities for tick score, worm egg count, buffalo-fly lesion score, rectal temperature, coat score, flight time, navel score and colour score ranged from 0.12 to 0.70. The heritability of most traits indicated potential to genetically improve these traits in both Composite and Brahman populations.