According to Jannie Fourie, National Woolgrowers Association (NWGA) production advisor, it’s important that pregnant women do not come into contact with sheep during lambing time in areas suspected of carrying the disease.
“The disease, also known as Chlamydia abortus bacteria, lives inside the cells of animals and can for a long time cause no symptoms. Should the host animal come under stress bacteria can multiply quickly,” said Fourie.
“Because the bacteria hides inside the cells of animals antibiotics cannot reach it. During multiplication the infected cell burts open and then antibiotics and vaccine will have an effect.” said Fourie.
The disease causes lambs to suffocate inside the uterus because of a shortage of oxygen. It also causes lung infection, blindness in young lambs and weak lambs at birth.
According to Fourie, the farmer must contact a vet as soon as abortion levels increase to above 3% to test for the disease. Pens must be disinfected and bedding and aborted material burnt.
“The clean herd becomes infected through the purchace of carrier animals. These animals may abort, or lamb normally. In both cases germs are scattered into the environment. Ewes and lambs then get these germs in through grazing,” said Fourie.
“Enzootic abortion disease settles chronically in a herd and reproduction losses will occur during every lambing season. Follow a good vaccination programme and vaccinate replacement ewes. Purchase only ewes from herds that are enzootic abortion disease free.
“Vaccines provide safety against abortions and the discharging of bacteria diminishes drastically. Lambs must be vaccinated from the age of five months, ewes must be vaccinated four months before pairing, but not less than four weeks before pairing.”
The extent of the disease is not known, but according to Fourie it has spread throughout the country and therefore it’s important that farmers should be aware of possible outbreaks in their area.