Aalbert Bussem explains cross ventilation
The ruminant digestion of cattle produces a great deal of heat. Furthermore, additional periods of prolonged heat occur every summer and affect many of the dairy cow's performance parameters. The first signs of increased respiratory rate, decrease in feed intake and shorter lying periods can be seen in high-performance animals as soon as temperatures reach 18⁰C. A respiratory rate of more than 70 breaths[/minute] indicates on its own that the animals are struggling with the heat.
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