Duration of performance tests for growth rate, feed intake and feed efficiency in four biological types of beef cattle

Residual metabolizable energy intake and its association with diet and test duration

“…The absence of large fluctuations in rank correlations observed in the 100% alfalfa, 100% fenugreek, 70% alfalfa + 30% barley grain, and 70% fenugreek + 30% barley grain diets further suggests that there are no major changes in the ranking of animals with respect to RMEI values within the diets 1997). The results of our study support the work of Archer et al (1997) and Archer and Bergh (2000) who suggested that a 70-84 d period was adequate to evaluate RMEI with no loss in end-of-test accuracy in bulls of different biological types.…”

“…Since RMEI is moderately heritable (0.35 < h 2 < 0.49), it has been used as a criterion to select breeding stock in tests that have facilities to record individual feed intakes. Testing periods of between 70 and 150 d have been reported in the literature (Archer and Bergh 2000;Liu et al 2000). A 140-d test is considered an industry standard for testing bulls for rate of gain in North America (Liu Abbreviations: ADG, average daily gain; ALF, alfalfa; DMI, dry matter intake; FEN, fenugreek; LSM, least square mean; RFI, residual feed intake; RMEI, residual metablolizable energy intake 291 and Makarechian 1993;Archer et al 1997), but Archer et al (1997 and Archer and Bergh (2000) suggested that a 70-d test was adequate to get an accurate measure of RMEI in sires of British breeds and other biological types fed standard test station diets.…”

“…Australian studies have shown that as marked differences in feeding patterns exist between Bos taurus and Bos indicus in the same feedlot (Robinson et al 1997), differences between breeds required to obtain reliable estimates of feed intake may exist (Archer et al 1997). However, in a subsequent study Archer and Bergh (2000) concluded that there is little evidence to suggest that differences exist between genotypes in the duration of performance tests required to accurately measure traits such as RMEI. Our study indicates that with respect to the accuracy of RMEI prediction, the duration of the test may also depend on the type of diet provided.…”

Analysis of Feed Intake of Individually Fed Beef Bulls Using Random Regression Models

“…Feed intakes were recorded every week during the test period of 84 d following a pretest adjustment period of 28 d (Archer and Bergh, 2000).…”

Input saving possibilities and practices contributing to more efficient beef production in Sweden

“…One may question whether the benefits (lower feed costs) derived from grazing cancel out the extra labour costs, and thus decrease farm costs overall while leaving production unchanged. Archer and Bergh (2000) and Bostad et al (2011) concluded that providing feed for animals is a major expense for beef production enterprises. For Swedish farms specializing in beef production, the marginal contribution of the production materials (mostly feedstuff) is twice the marginal contribution of the labour use .…”