How to sort out the picky eaters
Derek Casey looks at a Dutch solution to the problem of cows ‘feed sorting’ their winter rations
AWELL-KNOWN phenomenon on many farms during winter is the way in which cows move their noses through the feed in order to try and extract the tastiest feed.
Known as ‘feed sorting’, the process is costly and unwanted because it can leave valuable feed components wasted on the ground and lead to lower feed efficiency, ruminal acidosis and reduced dry matter intake. But is there any way of stopping cows from sorting their food at the barrier?
Dutch dairy farmers and father and son partnership Bert and Robert Versteeg think they have found a way to minimise feed sorting.
Last year, the Versteeg’s feed consultant pointed out that sorting behaviour by their cows could be reduced further despite their already good yield of 27kg of milk per cow per day. Bert Versteeg explained: “The feed looked well mixed to me, but a consultant visiting our farm was not satisfied.”
One of the consultant’s recommendations was a change in the loading order of the different feed ingredients.
The rations Bert gives his cows consist of pressed pulp, two different concentrates, grass silage and maize.
He drives his 10-year-old 18 m3 Solomix mixer feeder wagon along the concentrate silos and silage pits as part of his daily routine for loading.
The order in which the various feed components were loaded was mainly determined by the logistic organisation of the farmyard and by habit. The concentrate silos are next to the shed where the mixer feeder wagon is stored, so Bert logically started by loading the relatively fine concentrate and then drove from the shed towards the grass and maize pits.
Water was added between the concentrate and the silage to make the components stick together. The feed consultant’s assessment showed that the grass silage did not separate well and therefore did not mix properly when added to the rations as the final component.
The loading order was changed so that instead of loading the concentrate first, Bert now starts by adding the grass. He explained: “I first load the grass silage and then add one third of the maize.
“I mix that for about 15 minutes and I then add water and concentrate.” Loading the mixing tub with the textured grass and a little maize first makes it easier for the two augers to process the compact feed and for the auger knives to do their job.
“The finer concentrate components are not added until the grass has been cut and separated properly. All the mixing takes about half an hour. The new loading order makes it a lot easier to mix the rations and also requires less tractor power.
The auger knives were also considered. Both augers had five short knives.
One short knife at the bottom of the auger has now been replaced by a long knife, which loosens the compacted grass for easier mixing.
The use of the counter knives was not recommended for this ration. The counter knives are sometimes recommended to create back pressure in the mixing vessel to better cut the feed, but the benefits of counter knives are highly dependent on the type of roughage.
It is advisable to use counter knives for long shapes, such as round bales, but they may have the opposite effect on relatively compact roughage types.
With a few small adjustments, the Versteeg rations are now much better mixed and the cows are showing less sorting behaviour.
Bert added: “After three months, we can certainly say that the recommendations are having a positive effect on the selection behaviour and production. As well as loading order, the quality of the knives is very important and replacing them regularly can make a huge difference.”
AFTER THREE MONTHS THERE IS A DEFINITE IMPROVEMENT IN SELECTION BEHAVIOUR AND PRODUCTION
A well-mixed ration prevents the cows from feed sorting their winter rations