Synonyms

Anaplasmosis

Name of the disease in English

Anaplasmosis

The disease in brief

Anaplasma marginale is an infectious agent that causes this disease characterized by anemia, jaundice; it exists everywhere on earth, but with big differences: Enzootic in tropical regions, sporadic in our temperate zones, it loses its apparent importance there because it is often much rarer, or even unknown to many practitioners. It is more important in the southern zone of the EU, Mediterranean-Portugal and it should be considered that it exists everywhere in France.It has therefore been classified as a notifiable disease given the risks of its spread in the future.

This blood infection is transmitted by ticks (Dermacentor, Boophilus, Rhipicephalus, Argas) and biting flies such as Tabanus. Transmission by injection, surgical instruments, embryo transfer fluids is possible. Young animals do not develop the disease, which only appears after the age of 3 years, in naïve cattle; the disease can appear after a transfer of naïve cattle to an infected area or after the introduction of infected cattle into a healthy herd. Health certificates are essential for imports from an infected area.

Clinic & diagnosis

The disease may be suspected if pale to pale yellow vaginal or conjunctival mucous membranes are observed combined with:

-Fever, in the pasture

-Or normal urine, or sausage-shaped droppings, or a constipated and slaughtered cow.

Typical sign of the disease

No description

Pictures

See below

Diagnostic formulas

No description

Differential diagnosis

Theileriosis T.buffeli N45

-Mycoplasma weynyonii (Infection with) N33

–Poisoning by cabbages, onions, garlic N24

-Babesiosis-Mixed infection-Anaplasma / and / or Theileria buffeli- / OR M.Wenyonii N9

Confirm a suspicion?

Confirmation is made by taking a peripheral blood sample from a vein in the ear to take a blood smear. Anemia and elements are observed in the laboratory. punctate on the periphery of 10 to 50% red blood cells. PCR diagnosis is more sensitive and provides guarantees of specificity. Any well-founded suspicion must be reported to the DSV.

Prognosis and treatment

Treatment is with tetracycline 0.6-1g/100kg; a single dose cures, or two doses but the bovine remains a carrier. To sterilize a bovine it is necessary to switch to tetracycline 2g/100kg 2 to 4 injections one week apart.

-Imidocarb (0.3g/100kg) can be used.

- A transfusion is useful if the anemia is severe. The prognosis is reserved because the lethality is high in tropical areas.

Prevention

Any well-founded suspicion must be reported to the DSV. It is the authority that decides on the measures to be taken in such cases. In Switzerland, in 2002, the authorities had 300 cows from a herd where 2 cows had confirmed the disease slaughtered.

In enzootic zones, prevention is difficult and does not aim at eradication, which is considered impossible:

-Hygienic precautions during injections, surgery

-Vaccination with a problem of choice of killed/live vaccine.

-Tick control

-Treat clinical cases

References

Veterinary Medicine-Pocket companion -9th Edition BLOOD DC-page 447