1998/05/01 by E. Pérez, E. Perez, O. Gonzalez +8 · 2 citations
Immunology and Microbiology · Agricultural and Biological Sciences · #Toxoplasma gondii Research Studies #Agriculture and Farm Safety #Vector-Borne Animal Diseases
paper · doi:10.1136/vr.142.19.520
NEOSPOROSIS has recently been recognised as a major cause of \nabortion in dairy cattle worldwide (Barr and others 1990, Duff \nand Otter 1994, Boulton and others 1995). The disease is caused \nby the protozoan parasite, Neospora caninum, which is closely \nrelated to Toxoplasma gondii (Dubey and Lindsay 1993).Consequently, it may have a life cycle similar to T gondii, which \nis transmitted by ingestion of oocysts in the faeces of a definitive \nhost or by oral or nasal exposure to tachyzoites or oral exposure to bradyzoites (Thurmond and others 1997). For N caninum, however, \nvertical transmission is the major mode of transmission \n(Anderson and others 1997). \nIn Costa Rica, a retrospective study (1987 to 1993) on 23 dairy \nfarms located in a tropical cloud forest ecosystem (Holdrige 1987) \nfound an overall abortion rate of 7-6 per cent (515 abortions out of \n6741 animals calving). Consequently, a prospective study on the \nsame herds was planqed to determine the principal aetiological \nagents associated with abortion.