It's caused by the bacterium Mycobacterium bovis (M bovis), which can also lead to disease in many other mammals, including badgers.

Badgers can carry bTB and are able to transmit the disease to cattle.

The Queen guitarist has been a vocal animal rights activist for many years and leading calls for an end to badger culling.

His latest comments on the issue come after addressing an audience of farmers, vets and academics at Aberystwyth University in West Wales.

Badger culling has already been prohibited in Wales but the practice continues in parts of England.

Animal welfare organisation, the Save Me Trust, was set up by Sir Brian in 2010.

Its aim is to give wild animals a voice by addressing issues such as ending badger culling.

Sir Brian said he wanted to "find out the truth" about the relationship between cows and badgers in relation to bovine TB.

He has vowed to "fight" the disease alongside the farming community.

The National Farmers' Union has announced a strategy to eradicate bovine TB by 2038.

The policy currently enforced by governments in Westminster, Cardiff and Edinburgh is one of testing and removing cows with TB.

If a cow tests positive for bovine TB during a skin test, it is removed from the farm and sent to be slaughtered.

Scotland has been officially TB-free since 2009, meaning a low and stable incidence has been maintained there since then.

Bovine TB can affect nearly all organs and most often causes lesions to occur made up of bacteria known as Mycobacterium bovis.

According to the Royal Society of Biology, badgers are one of several mammals that can become infected by M bovis.

Infected and infectious badgers are generally asymptomatic and rarely show signs of bovine TB.

They shed M bovis through urine, faeces, phlegm and discharge from bite-wounds, the society says.

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Sir Brian has been supporting work at Gatcombe Farm, South Devon, to turn an infected farm into a TB-free zone.

"I am hoping my work will pave the way for a better understanding between the various stakeholders in the fight against bovine TB, and will eventually lead to a better life for farmers, cows, and badgers in the UK," he said.

"It is clear that Aberystwyth University is doing very important research in this field, and their work deserves support from all involved so that the scientific research on this disease can continue apace."