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The northern Australian beef industry, a snapshot. 2. Breeding herd performance and management

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AUSTRALIAN JOURNAL OF EXPERIMENTAL AGRICULTURE
卷 45, 期 9, 页码 1075-1091

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CSIRO PUBLISHING
DOI: 10.1071/EA03097

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Breeding herd performance and husbandry were surveyed on 375 northern Australian beef properties in 8 regions during 1996 and 1997. Mean branding rates ranged from 62.6% in the Northern Territory to 77.1% in the Maranoa South West regions of Queensland with considerable variation within regional herds. The proportion of herds using controlled mating was highest in the Central Coastal, Central Highlands and Maranoa South West. Mean mating period across all regions varied from 5.6 to 11.8 months. Calving was seasonal with peak activity in the August-December period. Calving commenced earlier in the south (August) than it did in northern regions (September-November). Rainfall influenced the timing of commencement of calving and peak calving activity. The use of pregnancy testing was widespread but selective and often not all females were pregnancy tested. About 97% of properties used weaning strategies with a peak in calf weaning in April-July, and a minor peak in September-October. Although mean weaner ages were similar across regions (5.9-6.9 months), mean weaner liveweight varied markedly with weaners in the more northern regions being lightest (<190 kg) while those in southern regions tended to be >200 kg. Culling criteria for cows and heifers focused on temperament, conformation and reproductive failure; age was also important for cows with a common culling age of 10 years. Bulls were more commonly culled at 7-8 years of age. In addition to age, bulls were culled for physical defects, reproductive problems, temperament and poor quality/performing calves. Four to 5 criteria were commonly used to select bulls. Structural soundness and temperament ranked highest followed by conformation, weight for age, Breedplan and colour. Producers using Breedplan tended to use structural soundness and temperament also as selection criteria. The results suggest that producers associated increasing turn-off weight or decreasing turn-off age more with pasture improvement than with bulls of higher genetic merit for growth. Supplementation of the breeding herd increased in the last half of the calendar year. Supplements containing molasses, urea, phosphate source, salt, and sulphate of ammonia were the most commonly supplied supplementary nutrients. Vaccination for botulism was quite common (>30% of regional survey groups) in all regions except Central Coastal and Maranoa South West regions of Queensland. Comparisons with previous surveys show that there have been marked improvements in breeding herd performance and management over an extended period. The results are discussed in relation to scientific developments over the last 2 decades and future development of the northern Australian beef industry.

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