Toxoplasmosis can cause abortions in sheep and goats

Small ruminant herds generally have a two to five percent abortion rate. Any percentage above this is a serious problem.

Toxoplasmosis is caused by the Toxoplasma gondii microorganism. It is a common cause of infectious abortion in sheep and goats, other animals and humans. Cats can be carriers of T. gondii, but typically only shed the organism when they are first infected. Cats often defecate and bury their feces in the hay and food storage areas of barns. Animals can become infected by ingesting food or water contaminated by these feces.

T. gondii enters the bloodstream of the ewe/doe and spreads to other tissues. In pregnant animals, T. gondii can invade and multiply in the placenta and pass to the fetus, causing fetal death, fetal mummification (where the animal reabsorbs the fetal fluid), stillbirth or the birth of weak kids/lambs. In some cases, the pregnancy can progress normally. Abortions from this microorganism occur mainly in the last trimester of pregnancy and may occur in animals of all ages and in successive pregnancies. To confirm the diagnosis of toxoplasmosis both the fetus and the placenta should be submitted to a diagnostic laboratory.

Humans can be infected by T. gondii by ingesting improperly cooked meat or unpasteurized milk from animals with toxoplasmosis. Pregnant women can also contract Toxoplasmosis and should not be exposed to direct contact with does kidding or ewes lambing or clothing or boots that may have been in contact with birthing fluids. Toxoplasmosis can result in miscarriage in women so pregnant women should take extreme caution at lambing or kidding time.

If toxoplasmosis is the cause of abortion in a herd, a veterinarian should be consulted. Feeding decoquinate (2 mg/kg bw/day) or monensin (15-30 mg/head/day) throughout pregnancy may reduce the abortion rate in a herd with a history of toxoplasmosis. Sulfonamides are used to treat toxoplasmosis in goats. Clindamycin (12.5 mg/kg, IM, BID for 3 weeks) is also recommended. There is no vaccine available in the U.S. for toxoplasmosis.

Many of these drugs are not licensed for use in goats and may only be used on the advice of a veterinarian. Good management practices can also help control toxoplasmosis. Pregnant females should not be exposed to infected cat feces so it may be necessary to limit the cat population in the barn where pregnant doe/ewes are housed or feed is stored.

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