Enzymes Activity of Local and Exotic Hens in Response to Seasonal Changes in Environmental Temperature of Saudi Arabia

This study was carried out to evaluate the physiological responses, in terms of enzymes activity, of local Saudi and exotic layers to seasonal variation in ambient temperatures. Three breeds of layers represented by Saudi Local (SL), Naked Neck (NN) and White Leghorn (WL) were used in this study. Estimation of alkaline phosphatase, creatine kinase, lactic acid dehydrogenase and aspartate amino transferase enzymes was performed according to the procedure listed by AOAC (2000). Result of the study indicated asignificant breed * period interaction was found only in creatine kinase. However, alkaline phosphatase, lactic dehydrogenase and aspartate amino transferase were affected by breed of the birds. Likewise, seasonal variations in temperature (effect of period) had a significant effect on lactic dehydrogenase and aspartate amino transferase enzymes. It was concluded based on this study and the biological responses of the birds to the seasonal variation in the temperature that naked neck birds can perform efficiently in areas where hot climate prevailed such as in Saudi Arabia.