Cooling, shed height, and shed orientation affecting dairycows microclimate [electronic resource].

Includes references.

Eight cowsheds were used, the differences between each cowshed are orientation (east-west or north-south), cooling (with or without), and height (5 m or 8 m height). Dry-bulb temperature, relative humidity, dew point, shaded area, air velocity, and maximum temperature were measured inside each shed. The temperature-humidity index (THI) and the shading efficiency were calculated for each cowshed. The trials were conducted using lactating Holstein Friesian cows; twenty cows housed inside each shade structure. Respiration rate, skin temperature, rectal temperature, moreover, the milk production of each cow, and feed intake were measured and recorded throughout the experimental work. Air velocities recorded under the higher sheds were higher than those recorded under the lower sheds which enhance the aeration; consequently, maximum temperatures, and THI recorded under the higher sheds were less than those recorded under the lower sheds. Thereby, increasing shed height enhances dairy cows microclimate under Egyptian conditions (hot climate); consequently, the milk production increases. The best orientation is the east-west orientation, which is preferable for hot climates. The exploitation of cooling has significant effect on microclimate, cooling enhances the ambient environment and provides comfortable zone for dairy cows which achieved high production levels. Keywords: Open Housing, Open Accommodation, Open-Lot Housing, Dairy Cows, Heat Stress, Cowshed, Shade Structure, Height, Low Shades, High Shades, Hot Climate, Orientation, Cooling, Micro-Sprinklers.

Summary in Arabic.

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