By organizing the BVDzero Award, the BVDzero team aims to encourage to search for both clinical and sub-clinical cases of BVD in cattle herds. We believe that the BVDzero Award will help to increase the awareness of BVD and, as a result, help to reduce its impact on the cattle industry.
The Award sponsor, Boehringer Ingelheim Vetmedica GmbH, has provided a total prize of 15,000€ for the top 10 clinical cases entered. Any person involved in the cattle industry is eligible for participation. Areas of expertise include, but are not limited to, research, diagnostics, animal science, veterinary practice, production veterinary medicine, cattle production and animal health & welfare.
The Hidden Risks of the Show Ring
A dairy farm in South Wales with a current Bovine Viral Diarrhoea (BVD) free status, after BVDv PCR testing the whole herd, had one positive and one suspect animal at the annual 5 animal youngstock screening for BVD antibodies. There was one positive animal in the previous screen a year before. Those positive results in young animals created confusion regarding the origin of the BVD infection in a free herd. Therefore, further investigation of the farm activities and the animal movements was necessary and revealed that the positive animal had been out of the farm for three cattle shows and for a total duration of three months, consequently, the animal became infected with BVD while being away from the farm and could transfer it back into the free herd.
The Cost of Not Vaccinating
Bovine viral diarrhoea is a worldwide disease of cattle of economic and welfare significance. It can be controlled and has been eradicated in several countries already. The virus generally causes a short-term infection. Clinical signs include fever, respiratory signs, drop in milk production, diarrhoea, embryonic death, abortion and occasionally death. These animals are only Transiently Infected (TI) – as they recover from the infection virus shedding stops. However, infection during the first third of pregnancy results in the unborn calf becoming Persistently Infected (PI) as the calf's immune system will fail to recognise the virus as something foreign and the virus remains active in the calf throughout its life. The PI calf's immune function is damaged permanently leaving it more susceptible other diseases e.g. pneumonia. Most PIs fail to thrive and die between 6 and 24 months. They either succumb to other disease or the BVD virus changes (mutates) and the animal develops Mucosal disease. This is invariably fatal. PIs continual shedding of virus is the main source of infection to other cattle.
Many studies have indicated a positive cost benefit analysis favouring control and eradication of BVD. Control of the disease instead relies on a combination of identification and euthanasia of PIs and vaccination. The main risks for BVD entering a herd are the movement of livestock (including boundary contact), personal and equipment.
BVD ‘Stamp It Out’ – The impact on 150 farms in North West England
The new BVD ‘Stamp It Out’ scheme gave opportunity for 150 farms in North West England to ascertain their current BVD status. 32 (21%) of farms showed evidence of active BVD infection and 34 cattle were identified as persistently infected with BVD virus. The scheme gave a significant boost to BVDFree England and had a positive impact on the number of farms vaccinating for BVD and using BVD ear tags.
Like mother, like (grand)daughter
A call from a small hobby beef farmer was received on our veterinary practice. The oldest of his four cows suffered from progressive diarrhea. The appetite decreased slowly while the diarrhea increased in the last two weeks. Only his oldest cow (7 years old) had clinical signs at this moment.
The farmer keeps his cattle as a hobby and for grazing his pastures during summertime. The farm is extensive and consists of two adult blonde‘d Aquitaine cows, one 6 months old calf (3 generations) and a Norman cow. The ‘granny’ blonde ‘d Aquitaine has been purchased as 2 year old cow. The ‘mommy’ and calf are both born on the farm. The farm had a history of Mycobacterium paratuberculosis before the ‘granny’ arrived on the farm. The farm did not participate in health programs for infectious diseases.
When something very fishy is going on… An unexpected case of BVD
A dairy farm with an average of 50 Prim’ Holstein and a few Normandy cows, managed single-handedly by the farmer, and a milk quota of 336,000 litres. The farm is rather well kept; a barn with straw bedding and no apparent problems. Nevertheless, three abortions were noted in the previous months. Serological tests for Brucellosis, BVD and Neosporosis were all negative. Q-fever serological tests all came back positive. PCR analysis on tank milk confirmed the passage of Coxiella burnetii in the herd.
With regard to BVD, biennial analyses showed no circulation of the virus in the dairy herd.