Pig classes at the Great Yorkshire Show were cancelled for the first time in the event's 161-year history when a pig showing signs of swine dysentry was identified at the Royal Norfolk Show two weeks previously.

The Great Yorkshire Show at Harrogate, had accepted entries of 354 pigs from 70 exhibitors, with the decision made to cancel the section last weekend as a matter of precaution while tests were done on the identified pig which had previously been shown at several other events. Tests carried out on the pig showing signs of illness have however since proved negative.

Although not a notifiable disease, swine dysentery can be a severe disease with a profound economic impact and while mortality is generally not high, feed conversion rates and evenness of growth are severely affected. The cost of this together with medication to limit clinical signs can easily be in the range of £10-£15 per pig produced.

Easily spread, the decision was made to cancel all classes, which included the prestigious Pig of The Year competition which takes place every year at the Harrogate event. A decision is still to be made as to whether this is to be rescheduled to another event in the near future.

A statement from the show organisers said: "Animal welfare is paramount and any potential risk to our exhibitors’ animals has to be taken very seriously which is why we took the difficult decision to cancel pig classes at this year’s Great Yorkshire Show.

The British Pig Association and the National Pig Association fully supported the decision and stressed the importance of biosecurity in all aspects of pig production and pig keeping.

Mandy Nevel, head of animal science at AHDB said: “Based on the circumstances, this is a responsible precautionary step and we are in agreement with the decision made.

“I would also like to remind all pig keepers, especially those attending shows, of the Significant Diseases Charter, and encourage them to sign up to help protect all our pigs. The charter plays an important role in sharing information quickly in the event of an outbreak of a disease including swine dysentery or Porcine Epidemic Diarrhoea (PEDv) which are a priority at the moment.

“The faster we can take action in the event of a disease outbreak, the faster we can stop it spreading.”