The Influence of Different Ambient Temperatures on the Body Temperature, Body Weight and Weight of Some Endocrine Glands of Male Chicks

Abstract

Less developed (14-day old) and well developed chicks (28-day old) in thermoregulatory ability were exposed to the ambient temperatures of 5, 20, and 35°C for 11 days in order to study the influence of these treatments on the body temperature, body weight and weight of some endocrine glands. The results obtained were as follows.
1) When 14-day old chicks were exposed to 5°C, 9 out of 49 chicks in total of four replicated experiments were died within the first 4 days following the exposure.
2) When 14-day old chicks were employed, the average body weights of the treated birds were heavier in the following order, 20°C>35°C>5°C, while in the case of 28-day old chicks the order was found to be 20°C>5°C>35°C.
3) When 14-day old chicks were employed, a treatment at 5°C resulted in lowered body temperature as compared to 20°C and 35°C groups. On the other hand, the treatment of 28-day old chicks at 35°C led to higher body temperature in average than those of 5°C and 20°C groups.
4) There was no significant difference in pituitary weight after any treatments, while a significant decrease in thyroid weight following treatment at 35°C was found with both ages of chicks(14- and 28-day old) when compared to 5°C and 20°C. A significant decrease in thyroid weight was also observed with 28-day old chicks on the fourth day after treatment at 35°C.
For the adrenal weight it resulted heavier in the following order, 5°C>20°C>35°C with a significant difference in 5°C.