THE EFFECT OF HEAT STRESS ON THE STANDARDS OF ACID BALANCE-THE BASEMENT FLAYING HENS

Abstract

This study was designed to evaluate the effects of heat stress on the stability criteria of acid - base and electrolyte balance of laying hens, as well as assessing the impact of the regionalization on the mentioned criteria. Thirty six white leghorn chickens were used chickens fed balanced diets for production stage, bird were divided into three equal groups. The first group was control while the second group was adapted to 38oC for a period of ten days before the start of the experiment. The third group (non- adopted) was exposed to the temperature of 38oC (two hours per day) for a period of thirty days. The results of the statistical analysis (p ≤ 0.05) to the adaptation have had a significant role in reducing the concentration of adrenocortical hormonal of the group and improve the level of serum hormone glutathaon the heat stress regardless of the adaptation had effect in raising the concentration of potassium ion and reducing calcium ion at the end of the experiment without affecting the level of sodium ion. Heat treatment also reduced the molecular pressure of carbon dioxide in both heat treated groups while the concentration of bicarbonates was elevated in non adapted group at the end of the As well as, the heat treatment in both groups led to lawering the volume of packed cells in both groups. The study concludes that heat stress has negative impact on the standards of the acid - base balance in laying hens and the effect of acclimatization period was limited in alleviating heat stress in chickens.