@conference {40389,
	title = {Computer Applications: Meeting the information needs of a business},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {52},
	year = {1992},
	month = {Jan},
	pages = {107-110},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Direct selection for 13-month live weight in NZ Angus cattle for  15 years has resulted in 17\% heavier yearlings and 12\% heavier adults  when compared with unselected control animals. The mean daily food  intake of growth-selected bulls is higher on a per head basis but is  similar when adjusted for differences in live weight. The objective of  this paper is to model the efficiency of a breeding cow herd, including  replacements, derived from selected and control lines. The index of  efficiency used is weight of calf weaned per unit weight of winter feed  required. Published performance data from the 2 herds are used to  quantify calf output and feed requirements are based on published growth  patterns in the 2 herds.   Our analyses show that, for the same winter feed requirement, the  selected herd when compared with the control herd would have: 88 vs 100  cows wintered; 65 vs 72 calves weaned, and mean calf weaning weight  would be 174 vs 158 kg per head. Efficiency was estimated to be 99.8 vs  100 units. Theses results indicate that while selection for yearling  weight has resulted in heavier calves and breeding cows, the calculated  extra winter feed costs associated with the heavier selected herd makes  them no more efficient than the randomly bred control herd. For the  selected herd to be more efficient, either a reproductive advantage well  in excess of the 3 percent point advantage achieved would be required,  or the metabolic efficiency of the selected cows would need to increase.  In economic terms, the selected herd may be more efficient than the  control herd for 2 reasons. Firstly, since herd size is lower, total  herd costs are likely to be lower. Secondly, if a premium exists for  heavier calves, the calves from the selected herd are likely to be worth  more per head.  },
	issn = {1176-5283},
	author = {Abell W}
}
