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Each year, an estimated 12,000 cows are injured by ingesting litter that has entered their feed. Another four thousand cows die as a result of hardware disease. Wageningen University and Research Centre looked into the effects of litter, concluding that hardware disease costs dairy farmers approximately EUR 14 million each year in medical treatment, death and reduced milk production.* However, there is a solution many dairy farmers are not aware of: magnets in the diet feeder.
Farmer Pim Lenferink knows first hand that magnets can prevent a great deal of injury. Last year he started using a mixer feeder with auger magnets for his 135 dairy cows. He was not aware of this product until his dealer explained he could place magnets on the augers. It was a purchase he definitely does not regret. He shows his 'harvest' on the kitchen table, picking out the most striking objects. His collection includes nails, barbed wire and screws along with other, sometime undefinable metal objects. Some have extremely sharp edges and are as long as a ballpoint pen. It is clear that these objects could most certainly injure a cow. "Within a month we collected around thirty objects", explains Pim Lenferink. "Every day we find sharp metal objects on the magnet. We were so impressed that we immediately installed a magnet on the second auger."
Birds could be the culprits
How these metal objects enter the feed is shrouded in mystery. Pim: "They could be thrown by school children or passing motorists. But we have also heard that crows pick up these types of objects to build their nests and then drop them because they're too heavy. Whatever it is, this collection certainly gives you something to think about."
You can't know what you don't see
Lenferink believes dairy farmers who claim not to have any issues with metal objects in the ration may be somewhat naive. "I also didn't know what the results would be. But I cannot imagine that other farmers are able to filter out all the sharp objects when preparing silage. After all, you can't know what you don't see. People often think they will find sharp objects in grass silage, but what about the by-products and the hay and straw bales?"
Last year, a TMR feed audit was organised on Lenferink's farm that was attended by many farmers from the surrounding area. That afternoon, they had the chance to see the mixer feeder wagon and the magnets in action. One of those inspired by what he saw that afternoon was a fellow farmer, who also had magnets installed in his self-loading mixer feeder wagon. The harvest after one year: A large cookie tin filled with sharp objects.
The advantages outweigh the amount spent
Lenferink made a striking discovery just recently. The magnets were covered with a thick layer of metal grit – extremely small particles of metal, most probably from a batch of purchased concentrate feed. Pim: "This doesn't immediately cause damage, but it shouldn't be in there. We would never have been able to retrieve it without the magnet. That just goes to show how important the magnets are. As far as I am concerned, this should be a standard feature of every mixer feeder wagon. It would save a great deal of animal suffering, and the advantages significantly outweigh the amount spent."
Trioliet offers three types of magnet:
1. Auger magnets
2. Magnet rods for a cross conveyor belt or chain
3. Magnet strip on the discharge chute near a side discharge door
The magnets can be retrofitted. Would you like to hear more about the options?
* Source: Student research: Cows dead after ingesting litter. Author: Albert Sikkema. Resource provided by Wageningen University and Research Centre, 28 February 2018. resource.wur.nl/nl/wetenschap/show/Studentenonderzoek-koeien-dood-door-zwerfafval.htm