With the on-going poor weather one is tempted to forget about heat stress! However, now we are in the peak of the summer season, the underlying temperatures are all much warmer than earlier in the year. Any slight rise in temperature or a sunny afternoon is enough to push the cows up into heat stress. We saw this towards the end of last week. Whilst it was not true ‘ice cream’ weather it was a bit warmer and also more humid – enough to push many of our farms from their weekly average ‘mild’ heat stress up into ‘moderate’ stress. Milk yields will have been affected as will fertility and standing times (which can lead to lameness problems in 8 – 10 weeks due to solar-ulcers). Predicted weekly average milk yield losses were around 0.5 to 1.0 liters a day but it was twice this on Friday and Saturday.
This week’s weather forecast is for the rain to clear and then a high pressure system will generate several hot days later in the week and it will remain hot and humid into the weekend.