TOXOPLASMA-GONDII INFECTION IN SHEEP AND CATTLE

Toxoplasma gondii is a protozoan parasite that can infect all warm-blo oded animals. Sheep and cattle show different susceptibilities to T. g ondii infection. Primary infection in pregnant sheep can result in abo rtion or the birth of weak lambs but they are then protected against f urther challenge by the development of an effective immunity. Cattle o n the other hand can be readily infected, but abortion or perinatal mo rtality have not been recorded. The evidence suggests that cattle deve lop a more effective immune response to T. gondii infection than sheep . Potential mechanisms to explain these differences are discussed in t his paper.