COSTA, F. T. R.; http://lattes.cnpq.br/9298681983539273; COSTA, Flávia Teresa Ribeiro da.
Abstract:
The Toxoplasma gondii is a protozoan of the Apicomplexa Phylum, having the
domestic cat (Felis catus domesticus) as its main definitive host. Known as one of the
most biologically successful agents among parasites, it has the capacity to infect more
than 200 different species, in addition to being responsible for causing one of the most
impacting zoonoses already described in the literature and for the occurrence of serious
reproductive disorders in domestic animals, especially in sheep. This dissertation
consists of two chapters: Chapter I entitled Evaluation of vertical transmission of T.
gondii in sheep naturally infected in the semiarid region of Brazil. In this article, we
sought to evaluate vertical transmission, through the presence of T. gondii
Immunoglobulin G (IgG) in naturally infected sheep, 55 sheep matrices were
monitored, of which 54.5% (30/55) demonstrated positivity in the Indirect
Immunofluorescence Reaction (RIFI). The mothers generated 41 puppies (58.6%) from
positive mothers and 29 puppies (41.4%) from negative mothers. The rate of vertical
transmission was 13.3% (4/30) of the deliveries of seropositive sheep, among which one
of the seropositive lambs had a titre of 16,384, the highest being found in this study.
The titers of mothers who generated seropositive puppies ranged from 128 to 8,192 and
no transmission was observed when the mothers had a titration of 64. Detection of anti-
T antibodies. gondii in conceptos indicated that vertical transmission is an important
means of transferring and maintaining agents in sheep herds in the Brazilian semiarid
region. In Chapter II entitled Systematic review and meta-analysis of the rate of vertical
transmission of T. gondii in sheep, the objective was to carry out a systematic review
with a meta-analysis to assess the rate of vertical transmission of T.gondii in sheep.
Nine studies were identified that involved studies of natural and experimental infection.
Six of the nine studies used the Indirect Immunofluorescent Antibody Test (IFAT) to
make the diagnosis. Most used two or more techniques to obtain the results. Through
meta-analysis, a high rate of vertical transmission of 66% was found. The significant
heterogeneity found is related to the different designs of the research and the lack of
standardization of diagnostic methods, demonstrating the need to carry out new works
aimed at vertical transmission in sheep and diagnostic standardization. These results
reveal that vertical transmission is an important agent transmission route. Thus, more
studies involving this theme clarifying aspects that are not yet clarified in the literature,
are necessary.