brucellosis in dogs: a comparison of brucella infection in herding and stray dogs in iran (tehran and west azerbaijan)

Brucellosis is one of the five most common bacterial zoonotic diseases worldwide, including in iran. although brucella canis is the known cause of brucellosis in dogs, infections with brucella abortus, brucella melitensis, and brucella suis have also been reported. the presence of non-specific brucella species in dogs may make them a potential reservoir for the main hosts of these species. this study investigated brucella’s presence in stray and herding dogs and compared their contamination. blood samples were collected from 156 dogs, including 60 stray dogs from tehran province and 96 herding dogs from some villages in west azarbaijan azerbaijan province, iran, in contact with cattle and sheep herds. then the level of contamination was evaluated using the rose bengal plate test (rbpt), wright, and polymerase chain reaction (pcr) tests and compared. brucella was found in 66 (42.3%) samples through rose bengal, 16 samples through wright (10.2%), and 1 (0.006%) sample through pcr methods. the herding dogs were more infected than the stray dogs. the higher contamination levels in the herding dogs compared to the stray dogs may be due to their close contact with farm animals, which are natural reservoirs of bacteria. this study confirmed the possibility of brucella transmission from cattle and sheep to dogs and possibly to humans, as well as confirming the role of dogs in the dissemination of disease to cattle and sheep.