Diagnosis of Brachyspira pilosicoli, Brachyspira hyodysenteriae and Brachyspira intermedia in hens and laying hens in the western region of Paraná through bacterial isolation and identification in qPCR

Abstract

ABSTRACT: Bacteria of the genus Brachyspira can cause enteric diseases in poultry causing a decrease in productivity. The occurrence of this disease in chickens has already been verified in countries such as Australia, Italy, and the United States, but in Brazil, until now, epidemiological studies about Brachyspira sp. frequency were only carried out on pig farms. The objective of this study was to evaluate the presence of bacteria of the genus Brachyspira sp. through isolation and confirmation of the species Brachyspira pilosicoli, Brachyspira hyodysenteriae and Brachyspira intermedia using the qPCR technique. Samples from 110 hens aged from 35 to 82 weeks were collected, 40 were from commercial egg farms and 70 were from laying hens matrices. For the first evaluation, bacterial isolation was performed from the feces. Positive samples were submitted to qPCR to identify the three species proposed. Cecum fragments of the birds were collected and fixed in formaldehyde for histological evaluation and counting of goblet cells. Of the 110 samples, 48 characteristic isolates of Brachyspira (43.6%) were obtained and of these in qPCR 13 identified as B. hyodysenteriae (11.8%) and 5 all from the same farm as Brachyspira intermedia (4.5%), 2 samples were positive for both agents (1.8%) and 28 were not characterized by qPCR (25.5%). None histopathological lesions were observed in the chicken cecum and no significant statistical difference was noticed in the count of goblet cells of the positive hens. It can be evidenced by the occurrence of Brachyspira sp. in laying farms and hens in Brazil, with special relevance to Brachyspira intermedia that can be potentially pathogenic for these animals.