Research note: sodium and potassium chloride drinking water supplementation effects on acid-base balance and plasma corticosterone in broilers reared in thermoneutral and heat-distressed environments

One experiment utilizing 188 Vantress X Arbor Acres broilers was conducted to evaluate the effects of isomolar KCl (.5%) and NaCl (.39%) drinking water supplementation on venous pH, PO2, PCO2, HCO3(-), hematocrit, and plasma corticosterone as well as rectal temperature and water consumption of broilers reared in heat-distressed and thermoneutral environments. Birds were allotted at 5 wk posthatch into either a thermoneutral (TN; 24 C) or cycling temperature (24 to 35 C) environmental chamber. Heat-distressed (HD) controls had elevated (P.05) body temperature (42.9 versus 41.7 C) and PO2 (144.5 versus 108.4 mm Hg). Blood pH, PCO2, and HCO3(-) (P.1) were not affected by high ambient temperature, but hematocrit (31 versus 32%) for HD controls was reduced (P .1) plasma corticosterone but KCl reduced (P.05) its concentration during heat distress and increased (P.05) bird survivability as compared with heat-distressed controls. The data reported herein suggests that KCl and to a lesser extent NaCl reduces HD consequences by a mechanism as yet undefined