By Lloyd Phillips
Dr Shaun Morris, an independent feedlot veterinarian, recently addressed KwaZulu-Natal dairy farmers about the threat and impact of foot-and-mouth disease. He has extensive practical experience in handling the disease, which has spread to the Eastern Cape dairy industry.
During his online presentation, it was clear that Morris wanted his audience to grasp the seriousness of the threat and the consequences of foot-and-mouth disease.
“Foot-and-mouth disease is no longer just your neighbour’s problem. In my opinion, it is now endemic in South Africa,” he told the meeting hosted by the KwaZulu-Natal Milk Producers’ Organisation.
“Although it appears that there is now a low mortality rate from foot-and-mouth disease in beef cattle, it shows very high mortality rates in dairy cattle. One reason for this is that dairy cattle are under high metabolic stress due to the large quantities of milk they produce. This undoubtedly affects their immune system.”
Morris said many dairy farmers have implemented biosecurity measures but they are probably unaware of how intensive management needs to be to prevent foot-and-mouth disease from breaking out in a herd.
While not wanting to cause alarm, Morris gave several examples of how easily foot-and-mouth disease can be unknowingly introduced to or spread by a herd. They included an animal infected with the virus shedding it from every bodily opening and via any bodily fluid and secretion, including semen, ocular fluid and milk.
Worsening the threat is that an animal infected with foot-and-mouth disease can be transmitting the virus to other animals before it starts showing clinical signs of the disease.
“People who have come into contact with infected animals can harbour the virus in their pharynx (throat) for up to two days,” he said, urging the farmers not to go near another farm that has susceptible livestock.
Foot-and-mouth disease can cause significant damage, pain and suffering to the teats and udder of dairy cattle, Morris said. Medications that are usually highly effective in treating conventional mastitis are often ineffective in treating foot-and-mouth-related mastitis. These cows will likely need to be culled.
He warned that once animal health authorities have placed a farm under quarantine, “you have very little further control over your operation. You become merely a pawn in the game of a disease that is entirely managed by the state.”
According to Morris, other potential sources of virus spread and how long it can survive in them include hay or straw (up to 20 weeks), dried manure (up to 15 days in summer), manure sludge (up to six months in winter) and soil (up to three days in summer and 28 days in winter).
“You can provide essential visitors to your farm, including veterinarians, with disposable overalls. Alternatively, for your farm personnel as well, you should set up permanent laundry facilities where they can thoroughly wash and disinfect their work clothes every day. These clothes, including work boots, should stay on the farm,” Morris said.
