Johne's Disease (Paratuberculosis)
Bovine viral diarrhoea
Persistent infections, persistent costs
Reduces animal productivity and slaughter value
£16,850 ($22,403) typical losses in 100-head beef herd
Suppresses immune response resulting in secondary infections
Total economic cost of £61 million per year in the UK
Bovine Viral Diarrhoea (BVD) is a highly contagious disease of cattle and among the most significant disease issues facing the cattle industry.
Poorer growth rates and milk yields
Immune suppression resulting in secondary illnesses such as scour, mastitis and lameness
BVD’s symptoms can vary greatly and appear visually similar to other infections. This makes outbreaks difficult to differentiate from other diseases. Though implied in its name, diarrhoea is not a universal symptom.
BVD is caused by a virus of a type similar to classical swine fever, zika, dengue and yellow fever viruses. It is present in most cattle-producing nations. Only in some Scandinavian nations has the strict use of diagnostics and bio-security resulted in the virus being completely eradicated.
BVD virus is spread primarily through nose-to-nose contact with infected animals. The majority of BVD infections occur after birth. These infected animals are less productive but are transiently infected and usually recover within two weeks.
Of more concern than transiently infected animals are those that become infected in the womb following viral transmission from the mother. These animals are persistently infected (PI) and continuously shed copious quantities of virus throughout their lives, routinely infecting other members of the herd. Within infected herds, it is estimated that there are 1 or 2 PI animals for every hundred head of cattle. PI animals are particularly costly if they are introduced into immunologically naïve herds that have not previously encountered the BVD virus. Detection of PI animals using specialist diagnostics is therefore essential for effective herd management.
Other sources of infection include semen from infected bulls, while other species including sheep, goats, swine, alpacas, deer, and camelids are also capable of contracting BVD and spreading disease. Typically, infection of non-cattle species species is believed to originate from infected cattle herds. However, wild animals may still be capable of spreading disease between farms or acting as an infective disease reservoir.
The economic damage of BVD infection can be severe. The UK’s BVD Free England scheme states that calf mortality in BVD-positive herds can be 7.5 times higher than in BVD-free herds, while the incidence of bovine pneumonia can be 28% higher. They also estimate that a 100-head beef herd containing the average of two PI animals suffers average annual losses of £168.50 ($224.03 USD) per cow, or £16,850 ($22,403 USD) for the whole herd. The total economic cost of BVD is estimated at £61 million per year in the UK and €100 million per year in the Republic of Ireland.
BVD infection also plays a role in the emergence of antimicrobial resistance (AMR) in livestock farming, as the weakened immune system of PI animals leads to more bacterial infections. Treating these infections is a significant source of antibiotic usage.
How Biotangents are tackling bovine viral diarrhoea
Prevention of disease outbreaks is the first step in combating BVD. Biotangents' Moduleic Sensing™ VET system will allow the accurate diagnosis of BVD on site, facilitating the certification of the BVD-free status of new animals before their introduction to the herd. This will minimise quarantine time, cost and the risk of BVD outbreaks in herds.
In suspected BVD cases, fast diagnostic decisions are essential to containing the spread of the disease. The rapid results generated by Moduleic Sensing™ VET tests will allow the removal of contagious animals from the herd, preventing further disease spread.
For laboratory sample testing, Moduleic Sensing™ LAB allows PCR-quality testing to be conducted without the cost of equipment or technical complexities. This offers a more cost-effective, high throughput diagnostic solution regardless of laboratory complexity.
Herd management and eradication schemes
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