Case Awards 2020

Our case takes place in the Nièvre department, in the heart of the Charolais basin. The farm is a breeder-fattener of Charolaise cattle. We will focus on the fattening unit where the respiratory problems appeared. The farmer has a building with 8 pens with straw bedding and a feed fence that can accommodate between 45 and 50 beef calves (approximately 10 -11 months of age when brought in). The conditions of the environment, bedding and feeding were all found to be adequate. There was no overcrowding in the pens or in the barn. The animals come either from a livestock assembly centre or from one of two Nièvre farms, with which the farmer is used to working, and they are gradually introduced into the barn pen by pen. The animals are not reallocated upon entering the barn.

This is a farm with 200 Holstein cows, housed all year round and milked three times a day. Its average lactation yield is 12000 kg. Officially, it is said to be a “closed” herd. However, in fact, it is not totally closed, with allowed transfer of living animals.

A 4-month-old Holstein Friesian male calf was presented to the Veterinary Health Center, Jordan University of Science and Technology for anorexia, respiratory distress and acute diarrhoea. The calf belonged to a small feedlot farm that contains 12 dairy calves used for feedlot purposes. Calves were vaccinated for enterotoxaemia, foot and mouth disease (FMD) and were given ivermectin. They had never been sick before. One of the calves was purchased from the auction market 2 weeks before this calf became sick. The calf became anorexic 7 days before presentation with increased temperature and respiratory rate. It developed watery diarrhoea 2 days later. The diarrhea was watery in colour. At that time, the calf was diagnosed with grain overload and was treated with magnesium sulphate and systemic and oral antibiotics.

Bovine viral diarrhea virus (BVDV) has a significant impact on health, antibiotic use and economics in the rose-veal industry. Nevertheless there hasn’t been a publication of a case that describes the impact of BVD vaccination on health, antibiotic use and economics at a rose veal farm with Bovine viral diarrhea virus circulation in the Netherlands. Because of the national BVD control program for dairy farms in The Netherlands, the number of sentinel animals increases and therefore the chance of a clinical BVD outbreak amongst veal calves. The reason would be an increased number of seronegative calves and co-mingled with persistently infected /transient infected calves onto rose veal calf farms. BVDV is known to be the most frequent isolated virus in relation to bovine respiratory disease (BRD). By reducing BVDV circulation in rose veal herds the incidence of BRD decreases. Therefore, BVD vaccination of veal calves could reduce the impact of BVDV on health and economics at the rose veal calf farm. Through vaccination of rose-veal calves, in the first week of arrival with a live BVDV vaccine (Bovela©, Boehringer Ingelheim) the antibiotic use decreased with 4,88 ADD (animal daily dose) and the mortality decreased with 2,77 %. This resulted in an economic benefit for vaccinated rounds of 5,66€/rose veal calf, compared to rounds that were not vaccinated on the same farm. The average slaughter weight was 1,84 kg less for the vaccinated rounds. If corrected for 1,59 less growing days for the vaccinated rounds the difference in slaughter weight is even smaller. Therefore, this difference is considered not biologically relevant and can be caused by different factors, but it does influence the financial results.

A small, lowland farm identified active Bovine Viral Diarrhoea (BVD) virus on farm through annual surveillance and subsequently identified persistently infected (PI) animals. Signs suggestive of Border Disease (BD) were seen concurrently in the co-located sheep flock which was diagnosed as BVD through blood testing. Control measures for both the cattle and sheep were introduced but signs persisted and a likely reservoir of infection in the sheep flock identified.

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.

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.

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.

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.

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.