Avaliaçâo da patogenicidade de Erysipelothrix sp. Strain 2 em modelo de embrião de galinha

Abstract

The genus Erysipelothrix sp are gram-positive rods responsible for an infectious disease, which can affect humans and wild, domestic animals. This work aimed to evaluate the changes that the Erysipelothrix sp strain 2 (ES2) may induce in chicken embryo's experimental model. In the evaluation of the pathogenicity of the microorganism, embryonated chicken eggs were inoculated with two strains (number 6 and 7) – characterized and sequenced – which were isolated during an outbreak between March 2014 and February 2015. On the 10th day of embryonic development, the concentrations of 1 and 3 log CFU/embryo were applied in the allantoic pathway. At 17 days of incubation, the embryos were weighed and their macroscopic characteristics were evaluated. The results of this experimental model showed that the concentration of 1 log CFU of strains 6 and 7 did not change the difference in embryo weight in relation to the negative control. Embryonic mortality rates were shown to be increased, the most significant being the concentration with 3 log CFU. Embryos inoculated with 3 log CFU of strain 7 showed lesions in the pelvic limbs, which did not occur in embryos with strain 6 at the same concentration. Furthermore, there were no differences in terms of pathogenicity between the strains. Therefore, strains 6 and 7 can be used in tests with born animals in order to better understand the pathogenicity of the disease.