Body water turnover in cattle with parasitic gastroenteritis

Total body water turnover and total body water volume in normal and severely parasitized cattle were studied with tritium labeled water. The parasitized cattle were all Hereford feeders which had acquired infections with Ostertagia ostertagi , Trichostrongylus axei , and Cooperia spp. while on permanent pasture. During the water turnover studies all animals had free access to feed and water. In one group of parasitized animals, an anthelmintic was used in order to determine the turnover rate of body water during convalescence. Analysis of results revealed the following: (1) The mean total body water volume in parasitized animals was 78 ± 1.08 per cent of the body weight. This represents an increase of 8 to 15 per cent over that found in normal animals of similar age. (2) The mean turnover rate (pool fraction per day) of body water in normal animals was 0.223 ± 0.043, while that of parasitized cattle was 0.110 ± 0.005. (3) After therapy the turnover rate in parasitized cattle began to increase within two to five days. Between 20 and 30 days after treatment the mean turnover rate was 0.158 ± 0.011. The reduced turnover rate of body water, assuming a steady state, reveals that in one group of parasitized animals the mean daily water flux was only 13.4 liters, whereas in normal animals having a comparable total body water volume the mean daily flux would have been 27.2 liters.