Rob Costello and Tom Rowe of Rowe Farm, Whittington, Gloucestershire suddenly witnessed a drop in milk output – something that was later attributed to mycotoxins. Our milk yields were inexplicably dropping and the cows started to scour, says Costello, who milks 180 Holstein Friesian on a high-input/high-output system. “Looking closer, we saw that dry matter intakes (DMI) had fallen by 2pc. Our adviser explained that mycotoxins were the cause and that the slight moulding on the top and shoulders of the clamps was the most likely source of the problem.”