Outbreaks of tick-borne disease cases in Santa Catarina, Brazil are known, but the presence of the pathogen DNA has never been determined. In this study, the first survey of Anaplasma marginale, Babesia bigemina, and Babesia bovis DNA on blood samples of 33 cattle from an outbreak in Ponte Alta Municipality, Santa Catarina, Brazil, has been carried out. A multiplex PCR detected 54.5% of animals were co-infected with 2 or 3 parasites, while 24.2% were infected with only 1 species. The most prevalent agent was B. bigemina (63.6%) followed by A. marginale (60.6%). This is the first report of tick-borne disease pathogens obtained by DNA analysis in Southern Brazil.

This study aimed to determine the prevalence of three common hemoparasites (Anaplasma marginale, Babesia bovis and Babesia bigemina) in cattle from 16 counties in the Campos de Lages region, Santa Catarina state, Brazil, and the factors affecting disease occurrence. The study population consisted of 257 clinically healthy animals from 21 rural farms. Bovine blood samples were collected by jugular venipuncture. DNA was extracted from whole blood by the phenol/ chloroform method. Genomic DNA extracted from blood samples was subjected to Multiplex PCR for screening of B. bovis, B. bigemina, and A. marginale using specific primers. Prevalences of A. marginale, B. bigemina, and B. bovis were 27%, 16%, and 29%, respectively. Mixed infection was observed in 17.5% of samples. The most frequent was Babesia bovis and Babesia bigemina in 6.62% of samples. A. marginale infection rates were statistically correlated with age groups of cattle. The infections detected in the study population were considered to be subclinical, based on the presence pathogen DNA and absence of clinical symptoms. Seasonality of the pathogens resulted in various degrees of infection, related to the age of the animals and the season. The Campos de Lages region is characterized by enzootic instability for these pathogens because of its climatic and geographic features.

Infectious arthritis or tenosynovitis in broiler and breeder chickens results in major loss of productivity because of reduced growth and downgrading at processing plants. The most common causative agents of avian infectious arthritis are the bacterium Mycoplasma synoviae and avian reoviruses (ARVs) (family Reoviridae, genus Orthoreovirus). In this study, we evaluated the occurrence of these two pathogens in arthritis or tenosynovitis lesions of broilers and breeder flocks in southern Brazil using molecular detection. Tissue sections from tibiotarsal joints with visible lesions from 719 broilers and 505 breeders were analysed using pathogen-specific polymerase chain reaction (PCR) assays. In breeders, 41.2% (n = 296) of lesions were positive for M. synoviae, 26.4% (n = 190) were positive for ARV, while co-infection was present in 12.2% (n = 88) of the samples. In broilers, 20.8% (n = 105) of lesions were positive for M. synoviae, 11.9% (n = 60) for ARV and 7.7% (n = 39) of these cases were positive for both pathogens. Post-mortem examination revealed lesions with varying degrees of gross pathological severity. Histopathological examination showed intense, diffuse lymphohistiocytic inflammatory infiltrates with heterophil accumulation, primarily in the synovial capsule and digital flexor tendon, in all samples. Improved strategies for early detection and control of these major avian pathogens are highly desirable for preventing the spread of infection and reducing economic losses in the poultry industry.

No abstract