[Comparative studies of climatic factors effecting the performance of cattle in different climatic zones of Egypt]

In continuation of previous analogous studies on climatic factors influencing the performance of cattle in Northern Egypt (climate types III4a/IV: etesian climate of the Mediterranean type) the present investigation deals with the temperature and humidity for Southern Egypt (climate type III1; arid, subtropical desert climate) and classifies them according to the physiological tolerability ranges set up for cattle. In Northern Egypt (Maryut) 23.8% of the temperatures were beyond the optimum and physiologically still tolerable range (0 to 24 degrees C) and were thus in the intolerable range; 45.8% were within the optimum tolerability range. In Southern Egypt (El Menia) 46.7% were within the intolerable range and only 25.7% in the optimum range (5 to 18 degrees C). The relative humidity values had 21.9% within the optimum range and 63.9% in the intolerable range in the North; in the South 22.9% were within the optimum and 55.5% in the intolerable range.