Weather: The very cold and often harsh weather is set to last well into next week. Air and more importantly soil temperatures have dropped considerably from their peak in late March.
Soil temperatures are now around 6-7°C, which is a bit below normal for the time of year, and, as air temperatures are set to dip again, I would expect soil temperatures to follow. grass growth rates are still good at over 30kg/day for the past week.
However, average growth rates are set to drop over the coming week to just over 20kg/day. To put this in context, average growth rates were just over 8kg/day for this week in 2018, so it’s all relative.
Never waste a good crisis. There is lots of grass available on most farms. The best thing farmers can do now is to clean out the farm and set it up to grow quality grass into May and June. In practice, this means letting average farm cover drop to 500kg to 550kg/ha before going in with heavy supplement such as silage. Hopefully the weather will have changed by the time the cover is at that point and so the supplement won’t be needed.
If your demand is 50kg/day and growth is 25kg/day then average farm cover will drop by 25kg/day. So if the average farm cover is at 750kg/ha today, then it will be 575kg/ha in one week’s time. This would put the farm in a great position for when the weather does change.
Diet: Pre-grazing yields in the second rotation are generally low enough at 1,000 to 1,300kg covers. When combined with relatively high meal feeding rates of 4kg/cow/day or above, it could cause some dietary issues. Make sure cows graze down tight so they are increasing the fibre content of the diet. Some farmers are alternating between first- and second-rotation grass by day and night in order to keep more fibre in the diet.
If grass is tight (grazing covers of 1,000kg) then going in with some long fibre such as high-quality bale silage might be better than feeding a lot more meal. Bringing cows in for silage for an hour or so before milking can generally supply about 2kg of silage dry matter per cow. Make sure there is enough feed space for all cows if supplementing with silage.
Calves: The oldest calves should be fit for weaning at this stage. By right, Holstein Friesian calves should be close to 100kg liveweight before being weaned off milk. Some farmers practise the early weaning approach whereby calves are put onto a high-meal diet pre- and post-weaning. They get meal ad-lib after weaning and are weaned off meal when they hit 100kg liveweight. These calves should have access to good-quality grass to increase the protein in the diet.
The weather, particularly in the northern half of the country, has been very harsh on any calves turned out to grass. Make sure calves that are outdoors have plenty of shelter. Shelter is critical from the northerly and easterly winds. Wean calves gradually, over the space of a week or so and try to avoid weaning and turning out to grass at the same time as this can be a big shock to the system.