Movement of water within the body of sheep fed at maintenance under thermoneutral conditions.

Abstract

Two mature Border Leicester x Merino wethers were maintained with continuous feeding under thermoneutral conditions. Their water balance was recorded for 2 weeks; at the beginning of each week they were given a dose of tritiated water (TOH) into the pulmonary artery or the rumen and samples were taken from both the pulmonary artery and the rumen. A four-compartment model was developed which simultaneously fitted the balance and tracer data. The half-time of TOH in body water was 6.7 days for one sheep and 7.6 days for the other; TOH space was about 55% of liveweight in both sheep. The bidirectional flux of water between the plasma-accessible compartment and 'bound' intracellular water averag..