A FORMER dairy farmer who has first hand experience of losing his herd to disease has taken up a new challenge to develop the Actiphage blood test for bovine TB and Johne’s Disease.

Jonnie Yewdall has been appointed commercial director at PBD Biotech which recently gained funding to take its Actiphage blood test for bovine TB (bTB) and Johne’s Disease through the validation required for international industry acceptance.

PBD Biotech Limited specialises in the use of novel bacteriophage-based technology in the field of veterinary diagnostics. The company has developed proprietary technology that can be used to detect the presence of mycobacteria such as Mycobacterium bovis (bovine TB) and Mycobacterium avium subsp. paratuberculosis (MAP; Johne’s disease), which are significant causes of loss of profitability in the agricultural industry.

Keen to help other farmers, Jonnie knows other too well the disaster diseases can bring to livestock as he lost a third of his Guernsey herd following a positive bTB test on the family farm in North Devon.

If that wasn’t bad enough further bad news was to follow when the replacement animals began to show signs of Johne’s Disease. That was the final straw for the family as the emotional toil and the ongoing financial loss were too great forcing them to sell the farm.

Jonnie said: “I think that Covid-19 has shown the wider business community what it is like to be a dairy farmer at risk from bTB; you are locked-down and can’t plan or budget.

“I don’t want any farmers to go through what we did, which is why I have joined PBD Biotech. With tools like Actiphage the industry has an opportunity to work together to potentially eradicate these very difficult diseases.”

Actiphage is an extremely specific test, as it detects the DNA from live bacteria in a sample of blood or milk, not just the animal’s immune reaction. It can detect just a few cells which enables farmers to identify carriers of the disease and remove them from the herd before they become spreaders. This was a recent recommendation from the cattle health certification standards regulatory body Checs.

Actiphage has been approved by APHA for use under special conditions, and when used on-farm as part of a disease management programme it has been proven to eradicate bovine TB.

By recently gaining £2.3million of funding, PBD Biotech is now able to take Actiphage through trials to gain OIE (the World Organisation for Animal Health) validation for the test which will enable international acceptance.

Jonnie sees potential for Actiphage to be used as part of a wider disease management programme to enable farmers to eradicate and then maintain a disease-free status on the farm.

He said: “Actiphage is a blood test for live mycobacteria that gives you a simple yes/no answer. When this is authorised for use on the farm, we could use it in parallel with the statutory testing to manage the infection risk, for example isolating inconclusive reactors pending a further skin test.

“It could be used as a ‘pre-movement’ test to check animals before they are introduced into a herd and also as a ‘DIVA’ test to differentiate infected from vaccinated animals, paving the way for the introduction of a vaccination programme,” he added.