Resumen

ROSMAR, V. et al. Patogenicity Changes of Eimeria acervulina in Presence of Aflatoxin B₁ in Broiler Chickens. Rev.Fac. de Ciencias Veterinarias [online]. 2005, vol.46, n.2, pp.61-73. ISSN 0258-6576.

With the purpose of studying the effects of the Aflatoxin B₁ (AFB₁), Eimeria acervulina, and its combination, was performed a study on broilers following  a design of treatments factorial type 3² totally randomized; with two factors: AFB₁ levels with non detectables levels, 20 and 200 mg/kg and E. acervulina with oocysts levels of 0, 250.000 and 500.000. The study included a total of 216 birds, during 5 weeks. Feed was contaminated with an AFB₁ standard, and desired levels were verified with Aflatest^® inmmunoaffinity technique. Each replica was feeded ad libitum. On the fourth week of age chickens were inoculated with E. acervulina. At the fifth week necropsy was performed and samples were collected for histopathological and parasitological studies. The apposition smears of E. acervulina resulted positive for the treatments where there was coccidia infection. The histologic studies for E. acervulina evidenced the effects of the two levels of treatment on the duodenum. When the two variables are present two situations are presented. At the level of 20 mg/kg of AFB₁ there was an increase in the pathogenicity for E. acervulina for both treatments. On the other hand at the level of 200 mg/kg of AFB₁, due to epithelial erosion effect on the intestinal villi, there was a decrease of the pathogenicity for the two treatments of E. acervulina. As for the effects on the weight gain it did not evidence statistically significant interaction between the two variables; but there was influence of the two levels of AFB₁ as with the two treatments of E. acervulina, producing a statistically significant of decrease in comparison with control treatment.   In conclusión there is evidence that  a level of 20 mg/kg of AFB₁ appears to make more susceptible the duodenum to E. acervulina infection. As long as the level of 200 mg/kg of AFB₁, it seems to decrease the pathogenicity of E. acervulina. There is no interaction between AFB₁ and E. acervulina on the weigth gain of chickens.

Palabras clave : Broiler chickens; aflatoxins; pathogenicity; Eimeria acervulina.