ABSTRACT
Un tercio de la población mundial poseen anticuerpos contra Toxoplasma gondii. El hombre se infecta a través de los esporozoitos provenientes de las heces de los gatos que contaminan la tierra, frutas, verduras y al agua; de los bradizoitos presentes en carnes que lo infectan cuando la consume poco cocinada o por su manipulación y por trofozoitos circulantes durante la fase hematógena en el hombre, infecta al feto a través de la placenta y a individuos seronegativos por órganos sólidos trasplantados o transfundidos con elementos formes de la sangre; son los llamados grupos de riesgos los más vulnerables a desarrollar formas graves de esta enfermedad que los puede conducir a la muerte. Estudios resientes corroboran la relación de esta infección con trastornos neurosiquiatricos, en particular con la esquizofrenia, así como su relación con accidentes de tránsito en conductores seropositivos; es de gran importancia tener presente las formas de adquirir la enfermedad y las medidas de precaución sobre todo cuando se ha demostrado que nunca se ha padecido la enfermedad.
One third of the world population have antibodies against Toxoplasma gondii. Human beings may be infected by sporozoites from cat faeces contaminating the ground, fruits, vegetables and water, by bradyzoites present in insufficiently cooked or improperly manipulated meat, or by trophozoites circulating during the hematogenous phase. Fetuses may be infected through the placenta, and seronegative individuals by solid organs transplanted or transfused with formed elements of the blood. These are the risk groups most prone to develop serious, life-threatening forms of the disease. Recent studies confirm the relationship of this infection to neuropsychiatric disorders, particularly schizophrenia, as well as its relationship to traffic accidents among seropositive drivers. It is paramount to bear in mind the ways in which the disease may be acquired and the corresponding prevention measures, especially for persons who have never had the disease.
ABSTRACT
Hematological parameters were evaluated in broilers immunized and challenged with Eimeria tenella. Broiler chickens of Hubbard strain, females, coccidian-free, were kept in wire cages and inoculated on the third day. The experiment was designed to include five sorts of treatment with three replicates each. T1 was the negative control group, T2 received 500 attenuated sporulated oocysts by gavage, T3 was the positive control, T4 received 50 µg of sporozoite protein + Quil A vaccine, and T5 received Quil A without sporozoite protein + PBS, the last two through nasal route on days 0, 7, and 21. On the 31st day, all treatments were challenged with homologous virulent strain of E. tenella in the dose of 8.0 × 10(4) oocysts, with the exception of T1. One week later, blood sampling, lesion scores, and cecal oocyst count were carried out. The parasitological parameters showed statistical significance (p < 0.05) and there was no damage to the hematological parameters of birds (p > 0.05) by ANOVA test. The correlations suggest that the blood parameters were impaired by effects of the parasite on tissue, showing levels of hemorrhage and/or hydration.
Foram avaliados os parâmetros hematológicos em frangos de corte imunizados e desafiados com Eimeria tenella. Pintos de corte fêmeas da linhagem Hubbard, livres de coccídios, foram mantidos em baterias metálicas e inoculados no terceiro dia. O experimento foi delineado por cinco tratamentos com três repetições cada, sendo: T1 controle negativo, T2 recebeu 500 oocistos esporulados atenuados via oral, T3 controle positivo, T4 recebeu vacina contendo 50 µg de proteínas de esporozoítos + Quil A e T5 recebeu Quil A + PBS, sendo os dois últimos por via nasal nos dias 0, 7 e 21. No dia 31, todos os tratamentos foram desafiados com cepa virulenta homóloga de E. tenella na dose de 8,0 × 10(4) oocistos, exceto T1. Uma semana depois, foi realizada amostragem de sangue, escore de lesão e contagem de oocistos cecais. Os parâmetros parasitológicos apresentaram significância estatística (p < 0,05), sem que causassem prejuízos aos parâmetros hematológicos das aves (p > 0,05), pelo teste ANOVA. As correlações sugerem que os parâmetros sanguíneos foram afetados pelos efeitos do parasita no tecido, apresentando níveis de hemorragia e/ou hidratação.