Avaliação da transmissão vertical de toxoplasma gondii em ovinos.

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.