'In the sun they'd cook': is the US south-west getting too hot for farm animals?

As temperatures rise, farmers are being forced to adapt, experimenting with new breeds and cooling methods

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South-west of Phoenix, Arizona, in the hottest desert in North America, Beth and Tim Wilson use sprinklers to cool their 300 pigs. Nearby, the Adams Natural Meats bison ranch employs shaders and misters. North of the city, chicken farmer Dave Jordan says he cannot put his 10,000 birds out to pasture.

If they were out in the sun, they would just get cooked."