The RSPCA should be encouraging improvements rather than "giving the industry a kicking", said the NFU's chief dairy advisor, Hayley Campbell-Gibbons, in the wake of the a statement this week on the charity's website.
Its assertion that the UK's Holstein-Friesian cow herd, which makes up the majority of the UK's dairy population, was suffering serious health problems due to inbreeding, was misleading, she added.
The Holstein breed had brought massive benefits to dairy farmers and had transformed the industry, agreed chairman of the NFU's dairy board, Gwyn Jones.
"They're not to be derided as some disease-ridden inbred machine."
However, the RSPCA insisted in the statement that the issue needed to be addressed. "We are urging retailers, farmers and consumers to all take responsibility for tackling the serious welfare concerns facing the dairy cow," it said, warning that inbreeding increased the likelihood of diseases such as bovine viral diarrhoea and leptospirosis.
If it was not addressed, the Holstein could lose the ability to produce milk at all by 2045, it claimed, citing University of Nottingham research.
However, the chairman of the Royal Association of British Dairy Farmers, Lyndon Edwards, disputed the RSPCA's comments.
"I think it's probably being blown out of proportion," he said. "I haven't seen the percentage of lameness they're talking about."
Dairy industry standards were already high and 95% of dairy farmers operated under the Assured Dairy Farm scheme, Gibbons claimed.
The Farm Animal Welfare Council, meanwhile, said it was conducting research on how dairy cow welfare had progressed since 1997 and hoped to publish its findings in the summer.