Associations Among Measures of Economic Efficiency

Abstract

First lactation production, feed consumption, and body weights of 425 Holstein cows were studied to evaluate associations among several measures of economic efficiency, 4% fat-corrected milk yield, income over feed cost, feed efficiency, and feed cost per 100 pounds milk. Two milk prices ($4 and $6 per 100 pounds) and one milk fat price differential (8¢ per .1%) were employed. Four feed price combinations between high and low prices of grain and forage were used to compute feed cost, feed cost per 100 pounds milk, and income over feed cost. High and low grain prices were $85 and $50 per ton (2,000 pounds). High and low forage prices were ($50, $60, $13) and ($30, $40, $9) where dollars within the parentheses represent prices per ton of alfalfa hay, alfalfa pellets, and corn silage.Mean income over feed cost, averaged over feed prices, was $232 per cow greater for high milk price than for low. High grain price was less detrimental to income over feed cost than was high forage price.Body weight was related positively to feed cost and feed cost per 100 pounds milk, but negatively related to income over feed cost. The regression of income over feed cost on body weight was curvilinear with a maximum at about 530 kg body weight or 50 kg below the herd average. Heifers may be bred to calve earlier and at smaller body size than is the practice in this herd.Milk price, feed price, and milk yield were the most important factors affecting income over feed cost, accounting for 60.0, 12.3, and 19.1% of the variation. Feed price and fat-corrected milk yield accounted for 76.7 and 9.0% of the variation in feed cost.Cows calving in January to March had both the highest feed cost and income over feed cost per cow whereas calving in July to September was marked by the lowest feed cost and income over feed cost.Within price-group correlations among the different measures of efficiency were high, indicating that the various methods of utilizing feed consumption data give about the same results in comparing different cows.