Diagnosis of experimental reinfection by Toxoplasma gondii by bioassay in pregnant goats

• Grant number: 11/01261-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2011
• End date: May 31, 2012
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Alvimar José da Costa
• Grantee: Henrique Meiroz de Souza Almeida
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

The high frequency of carriers of Toxoplasma infection goats, great possibility that these animals were re-infected with Toxoplasma gondii and the lack of literature on reproductive consequences in pregnant goats due to reinfection, motivated the proposed project. Twenty-five goats, one to three years old, serologically negative for T. gondii (IFAT-IgG), will be selected and these 20 will be infected with strain ME-49. The goats will thus be divided into five groups: five females re-infected with oocysts of T. gondii on day 40 of gestation (GI), five re-infected with oocysts of T. gondii at 80 days of gestation (GII), five re-infected with oocysts of T. gondii on day 120 of gestation (GIII), five infected reinoculated not retained as a positive control (GIV) and five females negative for toxoplasmosis, constituting the negative control group (GV). Seven days before the primary infection and will be held weekly clinical and serological (IIF). After reinfection, every three days until the 30th day after re-inoculation and every seven days until the end of pregnancy, and obstetric clinical examination will be conducted. Serum samples will be examined by IFA for antibodies against T. gondii. The bioassay will be performed with tissue samples from goats, aiming to detect parasitism by T. gondii by mouse inoculation. The cubs will be born alive euthanized and their tissues, too, will be examined for T. gondii, using the same technique described above. F tests are applied to treatment effects and Tukey a 5% significance for comparisons between the means and standard treatments. In summary, the objective of this research was to elucidate the importance of reinfection gondii in pregnant goats, but also describe the major pathological consequences resulting from this reinfection, a fact unprecedented in the literature.