Bovine tuberculosis and Johne’s Disease can devastate a herd if they are allowed to spread, but identifying infected animals at an early stage is problematic. Most traditional diagnostics rely on the immune response that only develops when the disease has progressed through the body.
Actiphage is a new phage-based blood test that can detect the presence of live mycobacteria, releasing its microbial DNA for identification. This enables the rapid diagnosis and the potential to manage the disease, reducing the loss of animals.
Johne’s Disease in goats and sheep
Milk from goats and sheep is a growing market – in demand for drinking and for yoghurt and cheese making – with approximately 110,000 milking goats and 20-30,000 milking sheep now dotted across the UK.
The true prevalence of TB and Johne’s in goats and sheep is unknown. Yet the outbreak of TB in a herd of goats can spread extremely quickly. It is thought they develop thin-walled lesions that are prone to bursting – unlike the granulomatous reactions, formed in cattle when trying to eliminate the infection. This can lead to whole goat herds being culled, with a devastating economic and emotional outcome for producers.
Johne’s Disease is an incurable bacterial, infectious disease that affects the intestines. Symptoms can include include weight loss and lethargy as well as diarrhoea.
Most existing TB and Johne’s tests, rely on an animal’s immune response, which develops only as the disease progresses. Actiphage is able detect live infection from a single milk or blood sample within hours, offering an early warning system that enables improved disease control.
TB in alpacas
South American camelids, including llamas and alpacas, are susceptible to M. bovis and can develop lesions and clinical signs of TB.
A small number of cases of TB are reported in camelid herds each year in Great Britain, some of these incidents have been quite severe, leading to loss of the herd and have occurred mainly in higher bTB incidence areas.
Testing available for both farm animals and exotics
The Actiphage test has the ability to identify TB and other mycobacterial diseases in animals before clinical symptoms of infection are observed.
It can detect with high specificity the presence of any mycobacteria in animal blood within 6 hours in comparison to culturing mycobacteria, which can take up to 12 weeks.
The technology has been successfully applied to blood samples from 17 different species so far, including alpacas, deer, goats and badgers as well as exotic animals such as lions, giraffes and camels.
Trials have confirmed PBD Biotech’s assay can detect live mycobacteria in blood or milk samples at very high sensitivity, of less than 10 mycobacterial cells per ml of sample.