New figures released by Merial Animal Health show that reduced milk yield caused by gutworm is costing UK dairy farmers over £314 million a year.

The data comes from five years of bulk milk tests, known as MOO tests, submitted to the QMMS for diagnosis and which are supported by Merial Animal Health. From 2009 to 2013 inclusive, 790 dairy herds across the UK have been tested and their level of gutworm challenge recorded. The MOO test measures the level of antibodies to gutworm in the milk – to assess the level of challenge to the cows. A ‘high’ result indicates the herd should be treated to remove gutworm.

“With margins ever tighter, a drop in milk yield and subsequent reduction in income is a serious threat to dairy farmers,” said Victoria Hudson, Brand Manager for Merial Animal Health. “Numerous studies have shown that gutworm has a damaging effect on milk production. Treating cows which have been infected with gutworm can increase milk yields by up to 2.6 litres per cow per day - over a 305 day lactation period that really adds up.”

Analysis of the latest figures indicates that on average 88.86% of the UK’s dairy herd are subject to a high gutworm challenge, putting over 1.6 million cows at risk from under-performance and costing farmers over £314 million in lost profit.