Predicting voluntary intake on medium quality roughages

Author: J.P. Pienaar, C.Z. Roux, P.J.K. Morgan and L. Grattarola
Year: 1980
Issue: 2
Volume: 10
Page: 215 - 225

A first order model for predicting voluntary intake was applied to sheep fed roughages differing in quality. Important variables identified in this study were the rumen capacity of the animals, the first order rate constant for fermentation of the diet, the solubility of the diets and the insoluble fermentable fraction of the diet. The first order rate constants for the outflow of fermentable and unfermentable organic matter from the rumen were found to be the same irrespective of the diet. Using estimates of these variables obtained from cannulated sheep, the intakes of intact sheep fed the same diets wen: predicted. Results medicated that a relatively unbiased estimate of voluntary feed intake on diets, including a legume and grass of widely different qualities, were obtained with another group of sheep using this method. Predicted mean intake was 665,9 g/day whilst actual mean intake amounted to 666,5 g/day. The standard error of the predicted means was 4,90 g/day.

Keywords:
Read article