Estimation of food intake of sheep grazing green pasture when no free water is available

Two experiments were made to measure the dry-matter intake of grazing sheep. Three groups of five ewes grazed three plots of young barley. The mean daily dry-matter intake per ewe from each group was estimated from the water turnover which was measured by the tritium dilution technique. The mean intake was also estimated by the double sampling technique for measuring standing crops. The mean estimate of one technique was within the standard deviation of the mean estimate of the other. The difference between the mean estimates from each technique did not exceed 18 %. It is concluded that water turnover could be useful for the measurement of the intakes of animals grazing green pastures.