Comparisons of body composition and energy utilization between Merino and fixed halfbred (Border Leicester × Merino) wethers

Abstract

Merino and halfbred weaner sheep were fed ad libitum for 6 months and food intake recorded; some animals of each breed were given a roughage-concentrate mixture and others were given a wholly roughage diet. The chemical composition of the body was determined from time to time.

The halfbred animals ate more of each diet and grew faster than the Mennos. The Merinos became progressively fatter, weight for weight, than the halfbreds; fatness was not affected by diet per se. There was no detectable difference between the breeds in energetic efficiency.

Prediction of the energy content of the body from tritiated water space measured in vivo gave similar results to carcass analysis.