Eperythrozoonosis (Mycoplasma ovis)
By Dr Mackie Hobson BSc(Agric),BVSc

1. Diseases

Eperythrozoonosis in sheep in South Africa is well known. Mycoplasma ovis  (Eperythrozoon ovis) may play a role in the ill-thrift syndrome in sheep and goats, particularly in the Eastern Cape Province of South Africa.

What is Eperythrozoonosis?

Mycoplasma ovis, previously called Eperythrozoon ovis, is a blood parasite (thought to be a rickettsia) primary of sheep that causes anaemia, jaundice and ill-thrift.

What are the clinical signs?

The majority of sheep and goats don’t show signs of disease.

• ill-thrift
• anaemia (pale gums)
• jaundice (yellow gums)
• dark red urine
• death (particularly following a stress event such).

How is Eperythrozoonosis spread?

Eperythrozoonosis is spread by the transfer of infected red blood cells from one animal to another. Outbreaks may occur 4–6 weeks after marking, ear tags, vaccination, shearing or mosquitoes and midges.

How is Eperythrozoonosis diagnosed?

Lab testing- serology and blood smears.

Treatment

• Tetracyclines
• Animals that recover naturally will develop immunity.
• Don’t move animals during an outbreak (for a period of 4–6 weeks).- usually have recovered from the disease.

Prevention

• Hygiene during tagging, vaccination and shearing.
• Control biting insects such as flies and mosquitoes.