The hot weather has eased after the weekend. All monitor sites had their hottest days last Sunday and since then many are at very mild levels of heat stress or even back to no heat stress. The average DHLI values show a clear North/South pattern with Scotland being the lowest. However there are other effects. The N Devon site is close to the sea and probably benefits from sea breezes whereas the Berkshire site is on the east side of a valley under a small cliff and the Sussex site is just north of the South Downs.
Over the past few weeks of hot weather cows will have started to acclimatise to the hotter weather. This acclimatisation will slowly wane but if we have another hot spell in the coming weeks they will cope better. An old farmer in Wisconsin once told me that his cows suffered the most in first heat wave – after that they impact was not so great.
