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1. Figure 1. Effect of Temperature and Humidity on Poultry Heat Stress 100 75 Relative Humidity, % 50 Danger high mortality Moderate stress High stress 25 Cool Comfort 0 20 25 30 35 40 45 50 Temperature, ° C

2. Figure 2. Energy and Heat Flow in Poultry Convection and radiant heat Evaporation heat loss from respiration Radiant heat Energy in feed Water intake (temperature important) Growth Activity Metabolic heat Conduction heat loss to litter and concrete Excreta heat and energy (loss of bicarbonate and potassium

3. Figure 3. Effect of Respiration Rate and Time on Stress 6 5 NORMAL 4 High Stress Hours Stress High Mortality 3 2 1 0 20 100 120 140 160 180 200 220 Respiration Rate (breaths/min)

4. Figure 4. Effect of Heat Stress on FCR in Broilers Time Temp RH days °C % FCR Exp 1 21-42 24 30 1.97 21-42 23-38 30-20 2.16 Exp 2 32-46 22 40 1.96 32-46 27-32 70-50 2.57

5. 350 Average $124 Exp 2 $182 Exp 1 $66 300 Average $106 Exp 1 $56 Exp 2 $156 250 Average $88.38 Exp 2 $130 Exp 1 $47 200 Average $70.70 Exp 1 $38 Exp 2 $104 Average $53 150 Exp 1 $28 Exp 2 $78 0 50 100 150 200 Savings per 1,000 birds, $ Figure 5. Economics of Heat Stress in Broilers Savings, heat stress vs normal temperature at various feed costs Average Feed cost $/MT

6. Figure 6. Open Broiler House with Concrete Floor bird mesh White or reflective roof E 3 m min N S 35 °min W insulation 2.75 m grass bird mesh and roll down plastic curtains 1.75 m concrete floor 12 m max drain

7. Figure 7. Open Broiler House with Slat Floors bird mesh white or reflective roof E 3 m min 35 °min N S W insulation bamboo or wood slat floor with 2.5 cm solid and 1 cm open 2.75 m gap to prevent rat entry bird mesh and roll down plastic curtains 1.75 m 12 m max 1.75 m metal rat guards sloping earth drain cement footings treated timber supports stairs or ramp