Internal medicine ruminants
Research domains
Our education is continuously adjusted based on recent publications. The treatment methods are always supported by the results of expert research. This team is currently conducting research in the following areas.
Respiratory diseases in veal calves
Infectious diseases of the respiratory organs (bovine respiratory disease (BRD)) is one of the most common diseases in calves worldwide, leading to enormous economic losses. Moreover, BRD is the most important indication for the use of antibiotics in calves. In a first series of studies in the veal calves sector, Mycoplasma bovis and the bovine viral diarrhea virus were identified as the most common pathogens. For practical and financial reasons antibiotic treatment for BRD is mostly immediately deployed without prior sampling. In view of a responsible use of antibiotics, it is preferable to have disposition of diagnostical techniques, validated to account for medication on the group level. These group diagnostics are, together with the identification of risk factors for BRD, especially in veal calves, the subject of further research for this team.
The use of antibiotics in veal calves
In recent years use of antibiotics in consumer animals is criticised ever more because of the possible role it plays in the development of resistant bacteria in humans. Antibiotics are frequently being strategically deployed to prevent disease, especially in intensive sectors like industrial poultry, pork and veal calves. A major epidemiological study in cooperation with Animal Welfare Flanders studied use of antibiotics in veal calves. Besides this, the causes for disease and mortality were mapped.
The resulting phd-thesis confirmed that the use of antibiotics in the veal calves sector between 2007 and 2010 was indeed excessively high and that the most important indication for the use of antibiotics were infectious diseases of the respiratory organs. This information helped identify various management measures that could help the sector to decrease the use of antibiotics at short notice without decreasing animal welfare or production. In follow up projects various preventive measures and therapeutic protocols will be tested in order to help the Flemish veal calves farming to evolve towards a more sustainable production method with less antibiotics.
Bovine neonatal pancytopenia
Since 2008 everywhere in Belgium calves of various races showed dermal hemorrhaging in the age between 10 and 14 days. 90 % of these calves died in spite of various treatments. This ‘new disease’ was studied in the research department and clinically, pathologically and epidemiologically described. All animals showed a total destruction of the bone marrow, which caused problems with coagulation of the blood and loss of any resilience. It became clear that there was a connection between the intake of colostrum and a certain vaccination against the bovine viral diarrhea virus. Further research in collaboration with the laboratory for immunology (UGent) showed that the blood of the mother animal contains antibodies that act against the white blood cells of the calves. In the meantime a definite link with this vaccination was internationally confirmed and it was taken off market. The disease is now found only sporadically.
Clostridium-enterotoxemia
Enterotoxaemia is an important cause of acute mortality in milk suckling, well growing calves. The disease is very acute (death in only a few hours), which is why the calves are often found dead. The symptoms are severe colic, bloated abdomen, shock and/or bloody diarrhea. Because of the acute development, treatment is mostly impossible. The disease is caused by, among others, the alpha-toxin produced by the bacteria Clostridium perfringens. Certain feed patterns could encourage the growth and production of the toxin. Typical are the red intestines seen during autopsy and hemorrhaging and necrosis of the tips of the intestinal villi during an histological examination.
At the moment there is a study going on in the research department that has as a goal the development of an effective preventive program based on feed management, vaccination and prebiotics.
Neurology
At this moment research is performed for the utility of the magnetic motore evoked potential test (MMEP-test) in calves.
With the magnetic motor evoked potential test (MMEP-test), is a painless test which can be performed on the unsedated calf, it is possible to stimulate the brain through the scalp (Fig. 1) which then provokes a muscle activity in the 4 legs. The amplitude and the duration of this stimulation can be printed on a graph.
The purpose of the study is to describe normal reference values for healthy calves.
Electromyography (EMG) is a technique for recording the electrical activity in muscle by a machine. The electrical activity becomes audible and visible by the use of an electromyograph. With some muscle disorders these signals become abnormal.