03/12/2025
A good explanation here. Many often only think sulphur is the culprit when in fact itās more likely a lack of fibre in many instances. In order to synthesise B vitamins such as B1 & B12 plus vitamin K, the rumen needs to ruminate & for that to happen effective fibre must be present. Lush growing pasture is NOT effective, āruminatingā fibre.
Wobbly calves? It could be vitamin B1 deficiency ā act fast! šāāļø
Vitamin B1 (Thiamine) deficiency can cause polioencephalomalacia ā which is a very fancy word, but essentially means swelling of the brain. This can show up about this time every season, and itās something to watch out for.
This condition occurs when thiaminase enzymes in the rumen destroy vitamin B1, which is essential for normal brain and nerve function. Without enough B1, calves develop brain swelling and severe neurological symptoms. The problem is often triggered by sudden changes in feed quality or high sulphur levels in water or feed.
Early signs include calves looking wobbly, āstargazingā with their heads up, isolating themselves, stopping eating and drinking, or hanging around water troughs. You might also notice ādonut eyesā which indicates brain swelling and dehydration. If untreated, symptoms progress to blindness, head pressing, circling, trembling, stiff legs, seizures, and eventually collapse or death. These signs can look a bit like pulpy kidney, listeria, or ryegrass staggers. Quick action is critical to turn the issue around!
The problem often appears in weaned calves during early summer, especially after moving from rougher pasture to lush, low-fibre paddocks. Fast weaning off milk and pellets, relocation stress or brassicas in the diet can also trigger it.
Prevention and early intervention is key! Take 10 minutes each day to observe calves for unusual behaviour. If you suspect B1 deficiency, act fast. Contact your vet for vitamin B1 injections and anti-inflammatory treatmentāvitamin B12 will not fix the problem.
Vit B1 Prevention Checklist š
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Transition calves slowly when changing feeds or weaning. You need to transition weaners if going onto very lush fresh pastures or any summer brassica crops.
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Keep calf feed in the diet for 6+ weeks after weaning
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Use a calf feed with good levels of B vitamins (Reliance, NRM and SealesWinslow Calf Max range have a good range of B group vitamins added)
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Check water for high sulphur levels
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Offer some dry long fibre alongside short, lush pastures
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Observe calves daily for unusual behaviour
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Monitor weight gains 2 weeks after weaning and every 4ā6 weeks thereafter
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If symptoms appear use electrolytes immediately - then call your vet for B1 injections and further help