Getting man and beast safely through the drought
July is upon us and the drought conditions continue.
Most of the country now has a three-inch to four-inch moisture deficit.
Fodder is unfortunately disappearing rapidly.
But farmers are resourceful and resilient, even in this demanding situation, and many different ways of dealing with the crisis are being implemented successfully.
Drought conditions are particularly serious on dairy farms, where grass growth disappeared over the last three weeks, even with excellent grassland management.
Good grass managers had been wrapping surplus grass and/or grass which had gone to strong and was not suitable to feed to cows for optimum performance.
Unfortunately, after wrapping the surplus, and taking the first cut of silage, we have had a significant reduction in growth rates, with most reporting only 20-25% of normal growth.
As we all know, June and July are difficult months to manage grass in normal conditions, never mind when there’s a heat wave and moisture deficit stress. There is no density or substance to most swards at present, with nothing more than stem and seed head in most paddocks.
One thing is for sure, if you allow dramatic drops in milk yield at the moment, you won’t be getting that milk back for the rest of the year.
Here’s a quick example.
If a 100-cow herd drops three litres per cow due to not getting enough energy from the supplied feed, what are the possible consequences?
We are now in the first week of July, so most cows have 140-150 days left in their lactation.
That equates to 42,000 to 45,000 litres less supplied from that farm. Yes, that milk is not produced for free, but when grass growth and grass quality recover, if the cows are still milking well, then they can produce it predominantly from grass.
The question is, can you afford to let your cows drop off this early in their lactation?
So how are herdowners dealing with the grass deficit?
- Feeding up to 6kg of concentrates in the parlour, and bridging any remaining deficit with silage, while remaining out day and night.
This silage can be fed once per day in the morning or evening. The morning is best, where possible.
Some are feeding this in the paddock by day, where all cows will have access. Many yards don’t have enough head space for a morning snack where all cows would need to eat at the same time.
If feeding 6 kg in the parlour, where possible, feed a bigger proportion in the morning.
- Housing cows by day and supplying anything between 50 and 70% of the total dry matter required indoors.
In intense heat, cows are happier indoors by day and grazing by night.
If cows are in by day in winter accommodation, they will have access to several water troughs, as opposed to the typical one trough per paddock.
This will keep them hydrated and cooler and encourage better appetite to maintain milk yields.
The forage supplied in this scenario is maize silage, whole crop, straw, baled silage, brewers grains, distillers grains, hay, pit silages of previous years, 2018 first cut silage, or zero grazing of either outside heifer blocks or grass intended for the 2018 second cut silage.
While all of these options will do the job of supplementing the remaining supplies of grazed grass on farm, some will need to be managed more carefully than others.
Maize silage, whole crop, brewers and distillers clamps must be well managed so that they do not heat in the current high temperatures.
These materials when heating can easily form moulds and toxins which can cause digestive upsets and scours.
All are excellent energy sources and will complement the scarce grass very well in the current climate.
With recently made bale silage, it is important that it has fermented properly before it is fed.
A high-acid loading during the fermentation process can induce digestive upsets and scouring. Silages in the pit or bales which was made more than three weeks ago are much more stable, and a better option, where possible.
Where zero grazing is bridging the grazing deficit, a few things need to be considered.
Grass mowed in the afternoon will have higher sugar and dry matter content, so it will be more valuable to the cow per kg of fresh weight consumed.
If you are zero grazing grass that was fertilised for second cut silage, what is its nitrogen content like?
Will you be supplying a very high nitrogen grass which could be detrimental to animal performance?
Excess protein in grass has to be processed by the cow before being excreted, this will use up her energy.
Those who have milk urea data from their milk collection can monitor this, to make sure that excessive levels are not being supplied. High blood ureas have been associated with embryo death.
The best option is to get grass tested for nitrogen before feeding it, if you are in any doubt.
Low covers of leafy grass will have very little fibre content, and could potentially run through cows, inducing acidosis if not complemented with a bit of fibre.
Straw, hay or dry bale silage will do this effectively.
This applies to cows that had been earmarked for culling later in the year anyway; surplus breeding heifers; any males that are normally sold in the autumn; and reared heifer calves that will not be required for the milking herd in 2020.
