EFFECTS OF SALINE ACCLIMATION AND CECAL LIGATION ON BODY-WATER AND WATER FLUX IN MALE AND FEMALE PEKIN DUCKS

Total body water, mean daily water flux, and plasma ionic and osmotic concentrations were determined in sham-operated and cecally ligated male and female Pekin ducks, Anas platyrhynchos, drinking fresh water and after acclimation to 0.3 M NaCl. Body mass, hematocrit, plasma sodium concentration, and osmolality were unaffected by saline acclimation or cecal ligation. Total body water of ducks acclimated to fresh water was about 63% of body mass and increased to 73% of body mass in all groups acclimated to 0.3 M NaCl except ligated females. Mean daily water flux of male and female ducks acclimated to fresh water was the same and was not affected by cecal ligation. Drinking 0.3 M NaCl increased mean daily water flux by 70% in both sham-operated male (P < 0.05) and female ducks (P < 0.01), and 135% (P < 0.001) in cecally ligated males, but did not affect cecally ligated females. Thus, following saline acclimation, mean daily water flux was greater (P < 0.05) in cecally ligated males than in females.