Epizootic haemorrhagic disease (EHD) has a strong impact on the milk production of an infected cow, first experiences in France show.
“While a cow is infected, it can lose almost the totality of its milk production. According to our specialists, the duration of the disease can be up to a month but recovering its productivity to the level of before the infection appears to be more complex,” says Christine Gocianski, economic analyst at the French technical institute for the livestock sector, Idele.
The effects of an EHD infection also vary significantly. “Some cows can be sick without showing any symptoms at all. In other cases, they have fever and show a lack of appetite, lesions or lameness.” Idele also found in the field that mortality appears to be higher than the 1% of infected cows which was earlier reported.
The total number of EHD cases in France is still rapidly increasing, with the department of agriculture in Paris reporting over 3,300 infected premises as of 20 November. The first case in France was only discovered on 21 September.
The cattle disease has now spread as far north as the Vendée region near Brittany, with the 150km protection zones currently at less than 500km from the border with Belgium. The discovery of a case in the Vendée also means the disease has made a jump of over 100km from previously infected areas.
In many French regions or departments, the situation on the ground is even more complicated because of the presence of both EHD and Bluetongue. According to the latest figures of the ministry, France has around 1,500 cases of Bluetongue serotype 8.
“The French livestock sector has to fight both those threats at the same time; that kind of co-infection is unique in the world,” agricultural magazine Web-agri states. That situation is currently happening in the very southwest of the country, in departments like Haute-Garonne or Pyrénées-Atlantiques, which borders Spain.
“That makes the job of a vet in the field far more complicated,” Emmanuel Garin of the organisation for animal health GDS France recently said at a conference. “When you have reports of animal diseases one week after another, you tend to think that it’s the same disease. But bearing in mind the spread of both EHD and Bluetongue, some doubt is certainly justified. The problems are even worse because both diseases show more or less similar symptoms.”