Worm exposure levels in dairy herds revealed
A study into stomach worm exposure in dairy cows has indicated high levels in 68% of UK herds. According to the test guidelines, this will have "probable sub-clinical effects on health and production".
Between September 2011 and March 2012, 449 milk samples were submitted by SQP animal health advisers and dairy vets, all of which were analysed independently.
Stomach worm (Ostertagia ostertagi) is the species identified most often in dairy cows, which is known to suppress appetite, claims vet Andrew Montgomery.
He said: "Numerous trials have found a yield response to worming treatment, typically in the region of 1kg per cow per day.
"At 25 per litre, this would be worth £76 per cow over a 305-day lactation, or about £16,500 per year in a typical 200 cow herd. Some trials have also identified improvements in reproductive performance although this remains to be proven absolutely."
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