Breed Cross Comparisons of Beef Cow Productivity Relative to Winter Feed Inputs

Abstract

Winter feed energy inputs (Meal digestible energy) were measured over a period of approximately 147 d in each of four successive years for two herds of mature beef cows. Each herd, one located at Brandon, Manitoba and one at Manyberries, Alberta, included 10 breed crosses, the Hereford × Angus (HA), which served as a control, and nine crosses produced by mating Charolais (C), Simmental (S) and Limousin (L) sires with Angus (A), Hereford (H) and Shorthorn (N) dams. The feed data for analysis represented a total of 2,994 cow years. Cow weight was used for estimating daily feed allowances with feed inputs increased during periods of extreme cold, increased as deemed necessary to maintain cow condition and (or) weight and increased during the final two months of pregnancy. Cow efficiency was estimated as Meal digestible energy per cow/average weight (kg) of calf weaned in all breeding seasons prior to the change in winter management required for measurement of feed consumption. Winter feed inputs at Manyberries averaged 16% higher than at Brandon. Winter weight gains, approximately equivalent to the products of conception, were recorded at both locations. Manyberries cows had much lower fat levels at the start of the winter feeding period and, despite substantially higher feed inputs, recorded substantial winter losses in average fat. The Brandon herd, with higher conception rates, lower calf mortality and higher weaning weights, averaged 16% above Manyberries in lifetime productivity and 47% better in cow efficiency. Breed cross rankings for winter feed energy inputs were Cx>Sx>Lx>HA at both locations and closely mirrored differences in average cow weights. Most breed crosses, including the six Cx and Sx ranked well above the HA in productivity. For cow efficiency, the HA was approximately 8% more efficient than the CH and LA at Brandon and the LH at Manyberries while the Sx at both locations and the Cx at Manyberries were more efficient than the HA. Copyright © 1987. American Society of Animal Science . Copyright 1987 by American Society of Animal Science.