Compartir
Título
Placental thrombosis in acute phase abortions during experimental Toxoplasma gondii infection in sheep
Autor
Facultad/Centro
Área de conocimiento
Datos de la obra
Veterinary Research, 2014, 29, 45
Fecha
2014
Abstract
After oral administration of ewes during mid gestation with 2000 freshly prepared sporulated oocysts of T. gondii
isolate M4, abortions occurred between days 7 and 11 in 91.6% of pregnant and infected ewes. Afterwards, a
further infection was carried out at late gestation in another group of sheep with 500 sporulated oocysts. Abortions
happened again between days 9 and 11 post infection (pi) in 58.3% of the infected ewes. Classically, abortions in
natural and experimental ovine toxoplasmosis usually occur one month after infection. Few experimental studies
have reported the so-called acute phase abortions as early as 7 to 14 days after oral inoculation of oocysts, and
pyrexia was proposed to be responsible for abortion, although the underline mechanism was not elucidated. In the
present study, all placentas analysed from ewes suffering acute phase abortions showed infarcts and thrombosis in
the caruncullar villi of the placentomes and ischemic lesions (periventricular leukomalacia) in the brain of some
foetuses. The parasite was identified by PCR in samples from some placentomes of only one sheep, and no antigen
was detected by immunohistochemical labelling. These findings suggest that the vascular lesions found in the
placenta, and the consequent hypoxic damage to the foetus, could be associated to the occurrence of acute phase
abortions. Although the pathogenesis of these lesions remains to be determined, the infectious dose or virulence
of the isolate may play a role in their development
Materia
Peer review
SI
URI
Collections
- Untitled [2808]