The past week has been typical weather for May – nice sunny periods with some showers.
The image below shows the heat stress situation for grazing cows on our monitor farm in Berkshire.
The sunny afternoons push the index up into the yellow Moderate zone on most days and on Tuesday and Sunday up further into the High risk zone.
Cows will be feeling the effect of the heat – especially if they have no shade. Their behaviour will change as they seek out shade, water demands will increase and cluster into ‘camps’. Feed intake will drop in the heat of the afternoon so it is important they have ample grazing available in the long, cooler evenings.
At present the DHLI index drops away at night and the cooler period allows cows to shed any heat load that built up during the day. Heat load does not accumulate so impact on production will be limited.