Veterinary Research Forum

Abstract Pasteurella multocida and Mannheimia haemolytica are significant bacteria of respiratory tract infections in cattle. Identifying whether these bacteria are commensal or pathogenic is crucial for understanding their role in predisposing calves to respiratory tract infections. This study aimed to determine the prevalence and pathogenic characteristics of P. multocida and M. haemolytica in nasal swab samples of clinically healthy calves in Konya, Turkey, and to assess antibiotic resistance profiles. Using conventional culture methods, 5 samples (1.67%) from 4 different farms were positive for P. multocida and 3 samples (1%) were positive for M. haemolytica. PCR of nasal swab samples yielded P. multocida positivity in 17 (5.67%) samples and M. haemolytica positivity in 13 (4.33%), including all culture-positive samples. While all P. multocida isolates were atypical for the capsule, 18% of the PCR-positive samples were L2, 70% L3A, and 12% L8 serotypes. The ompA, omp87, hghA, and tbpA genes were the most prevalent, while the presence of other virulence genes varied. High rates of ampicillin/cloxacillin (100%) and streptomycin (80%) resistance were observed among the isolates. The rates of serotypes A1 and A6 in M. haemolytica PCR-positive samples were 53.85% and 46.15%, respectively. The ssa-1 gene was detected in 33.33% of the isolates. Moderate resistance to trimethoprim/sulfamethoxazole, streptomycin, and neomycin (66.67%) was recorded. The findings revealed the presence of P. multocida and M. haemolytica with various virulence characteristics and antimicrobial resistance profiles in the nasal microbiota of healthy calves, providing novel insights that could inform improved herd management, disease control, and treatment strategies.

Abstract The Q fever is a zoonotic bacterial infection caused by an obligate intra-cellular bacterium, Coxiella burnetii. Members of the Canidae family (Mammalia), including dogs and foxes, are potential reservoirs of C. burnetii, which has a wide host range from mammals and birds to arthropods (primarily ticks). Infected dogs can transmit the disease to other animals and humans. This study aimed to investigate the presence of C. burnetii in dogs and ticks collected from infested dogs in the Kars, Ardahan, and Iğdir provinces of Türkiye by serological and molecular methods. Three hundred canine serum samples were analyzed for phase I and phase II C. burnetii antibodies using indirect enzyme-linked immunosorbent assay. Whole blood samples (n = 300) from the dogs sampled for sera and 184 ticks randomly collected from these dogs were also analyzed for C. burnetii with touch-down polymerase chain reaction. The ticks were classified according to the taxonomic characteristics. In result, 107 tick DNA samples collected from individual females and pooled males were evaluated. The C. burnetii was detected in 3.73% (of the tick samples. However, C. burnetii was not detected in any of the canine blood samples by polymerase chain reaction. Out of the 300 dogs, 18.33% presented antibodies against C. burnetii in their blood serum. When assessed for location, C. burnetii seropositivity was found to be significantly high especially in the Northeastern Anatolia region (18.33%). Study data highlighted the zoonotic risk of ticks, demonstrating that ticks on dogs can carry C. burnetii.