Thermoregulatory responses of laying hens under cyclic environmental temperature to intraventricular calcium and sodium.
1. Hens received ICV injections of Ca2+ (1.98 g/100 ml) or Na+ (7.25 g/100 ml) at 28 degrees C and, following acclimation, at 37 or 20 degrees C, respectively. 2. At 28 degrees C (thermoneutrality), rectal temperature rose (P less than 0.05) following Na+ and fell (P less than 0.05) following Ca2+, similar to mammals and broiler chickens. 3. At 37 degrees C, Ca2+-induced hypothermia did not occur; nor did the Na+-associated hyperthermia at 20 degrees C. 4. Acclimation to a high or low temperature may produce an endogenous shift in CSF ion levels that make additional ion administration ineffective in affecting body temperature.
D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D001833:Body Temperature Regulation / Q000187:drug effects*; D002122:Calcium Chloride / Q000008:administration & dosage / Q000494:pharmacology*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D002645:Chickens / Q000502:physiology*; D005260:Female; D007276:Injections, Intraventricular; D010058:Oviposition; D012119:Respiration / Q000187:drug effects; D012965:Sodium Chloride / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
D012965:Sodium Chloride; D002122:Calcium Chloride