Angry French farmers are calling for more protests over the government-backed slaughter of cattle herds affected by so-called Lumpy Skin Disease (LSD).

On Thursday, there were clashes between riot police and demonstrators in the southern Ariège department after vets were called in to destroy potentially contaminated cattle.

Elsewhere in the south, farmers have dumped manure outside government buildings and blocked roads. The offices of several environmentalist groups were ransacked in the Charente-Maritime department.

LSD is a highly contagious bovine disease transmitted mainly by fly-bites, with symptoms including fever, mucal discharge, and skin nodules.

Though mainly non-fatal, it can severely affect milk production, rendering the cows unsaleable.

The disease arrived in Europe from Africa about ten years ago, with France's first outbreak occurring in the Alps in June that disrupted the Tour de France cycle race.

The government's policy of slaughtering entire herds where a single animal has been infected has faced significant opposition from two out of the three main farmers' unions, the Confédération Rurale and Confédération Paysanne, who argue that a combination of selective culling and vaccination would suffice.

Most veterinarians, however, contend that without distinguishing between healthy and asymptomatic infected animals, mass slaughters are necessary. As of now, approximately 110 LSD outbreaks have been reported in France, resulting in the slaughter of around 3,000 animals.

The French government is concerned that ongoing protests could escalate further among an agricultural community increasingly threatened by EU regulations and international competition. A large protest is scheduled in Brussels next week coinciding with an EU summit, amidst wider agricultural crises impacting various sectors such as wine and poultry farming.

Furthermore, there is significant apprehension about an upcoming EU free-trade agreement with South American nations, which farmers fear could flood France with cheaper food imports produced under weaker standards.