More than 3,100 vocational qualifications, which also include fish husbandry and travel and tourism and are currently regarded as equivalent to GCSEs, are to be cut out of school league tables because they have caused "perverse incentives" for schools to count them towards their results, ministers said.

The changes follow last year's government-backed review of the vocational training system by Professor Alison Wolf, who said performance tables encouraged schools to offer "inadequate qualifications".

But Charlie Mullins, who contributed to the Wolf report and is founder of Pimlico Plumbers, countered that vocational qualifications, which helped to boost economic growth, should be measured.

He also called for the coalition government to place greater focus on traditional trades such as plumbing, building and carpentry in order to alleviate the current skills shortage in such sectors.

"The very fact that fish breeding and traditional skills like wood- and metal-working have been conflated into the same category of vocational skills just goes to show how we’ve ended up with poorly skilled young people. If schools want to count vocational courses in their league tables, they should have to be in the traditional trades that will actually help make an impact on youth unemployment," Mullins said.

He added that the vocational education system had "become rotten and so entrenched that it has taken a huge amount of bravery, firstly from Professor Wolf, and now the education secretary, Michael Gove, to attack the system".