A comparison between seasonally mated and continually mated Bos indicus cross heifers on the Barkly Tablelands of the Northern Territory [beef cattle]
1994
Stefani, J.A. (Northern Territory Dept. of Primary Industry and Fisheries, Tennant Creek (Australia). Animal Production Section)
A producer demonstration site was established to compare controlled mating versus uncontrolled mating. There were 257, mostly 1 year old but some 2 year old, Santa Gertrudis heifers randomly selected. These heifers were individually identified and randomly allocated to either a controlled mating group or an uncontrolled mating group. Bulls were introduced in March and removed in September or October in the controlled mating group, compared to bulls being run all year round in the uncontrolled mating group. Reproduction, lactation, condition and weight measurements were recorded. Conception rates averaged 50.7 percent and 56.5 percent for the controlled and uncontrolled mating groups respectively. Branding percentage favoured the controlled mating group at 61.3 percent compared to 55.6 percent for the uncontrolled mating group, however, this difference was not significant. Average conception rates were higher in the uncontrolled mating group, however, branding rates were higher in the controlled mating group. Heifer mortality rates were significantly lower in the control mated herd at 2 percent compared to 8 percent in the uncontrolled mated herd. The cost benefit of controlled mating was significant. Heifer mortality rates over 4 breeding seasons decreased by over 5 percent in the controlled mating group in comparison to the uncontrolled mating group.
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