The high complexity of the oral microbiota of healthy dogs and the close exposure of humans to companion animals represent a risk of the transmission of potential zoonotic microorganisms to humans, especially through dog bites, including multidrug-resistant ones. Nonetheless, a limited number of comprehensive studies have focused on the diversity of the microorganisms that inhabit the oral cavities of healthy dogs, particularly based on modern molecular techniques. We investigated bacterial and fungal organisms in the oral cavities of 100 healthy dogs based on a combination of conventional and selective microbiological culture, mass spectrometry (MALDI-TOF MS), and next-generation sequencing. In addition, in vitro antimicrobial susceptibility patterns of isolates and mecA resistance gene were assessed. A total of 213 bacteria and 20 fungi were isolated. Staphylococcus pseudintermedius (40/100 = 40%), α-hemolytic Streptococcus (37/100 = 37%), and Pasteurella stomatis (22/100 = 22%) were the most prevalent bacteria diagnosed by microbiological culture and MALDI-TOF MS, whereas Aspergillus (10/100 = 10%) was the most common fungi identified. Based on next-generation sequencing of selected 20 sampled dogs, Porphyromonas (32.5%), Moraxella (16.3%), Fusobacterium (12.8%), Conchiformibius (9.5%), Bergeyella (5%), Campylobacter (3.8%), and Capnocytophaga (3.4%) genera were prevalent. A high multidrug resistance rate was observed in Staphylococcus pseudintermedius isolates, particularly to azithromycin (19/19 = 100%), penicillin (15/19 = 78.9%), and sulfamethoxazole/trimethoprim (15/19 = 78.9%). In addition, the mecA resistance gene was detected in 6.1% (3/49) of coagulase-positive staphylococci. Here, we highlight the microbial complexity of the oral mucosa of healthy dogs, including potential zoonotic microorganisms and multidrug-resistant bacteria, contributing with the investigation of the microbiota and antimicrobial resistance patterns of the microorganisms that inhabit the oral cavity of healthy dogs.

Rhodococcus equi is a well‐recognized Gram‐positive intracellular facultative bacterium that is opportunistic in nature, which causes pyogranulomatous infections in humans and multiple host animals. The pathogenicity of the microorganism has been attributed to the presence of plasmid‐encoded virulence‐associated proteins (Vap). To date, three host‐associated virulence plasmid types of R. equi have been identified as follows: the circular pVAPA and pVAPB, related, respectively, to equine and porcine isolates, and a recently described linear pVAPN plasmid associated with bovine strains, although these three types are found in human isolates. Recent phylogenomic studies support the evidence that human R. equi infection is zoonotically acquired. Nevertheless, data regarding distribution and prevalence of the host‐adapted virulence plasmid types of R. equi isolated from meat animals are scarce or unnoticed. Here, the three host‐associated virulence plasmid types (pVAPA, pVAPB, and pVAPN) were investigated in 154 R. equi isolates recovered from lymph nodes of cattle with lymphadenitis (n = 31), faeces of cattle without enteric signs (n = 49), as well as different clinical specimens from human patients (n = 74). The analysis of virulence profile of 74 R. equi from humans revealed six (8.1%) isolates pVAPB (type 8), two (2.7%) pVAPN, and one (1.3%) pVAPB (type 11), all of which were from lung samples from people living with HIV/AIDS. From the lymph node samples of cattle, 41.9% (13 of 31) isolates revealed pVAPN type, whereas all isolates from faecal samples were negative for three host‐associated types. Here, recently described bovine‐associated pVAPN type was detected in R. equi isolates recovered from the lungs of people living with HIV/AIDS and lymph nodes from slaughtered cattle intended for human consumption; a finding that represents a public health concern, mainly in countries where undercooked or raw meat are traditionally consumed.

Tetanus is characterized by high case fatality rates in horses. Comprehensive case series studies involving equine tetanus from different geographic areas enable the evaluation of prognosis, efficacy of treatment, and control measures. We retrospectively investigated some selected epidemiological data (breed, age, gender, use of the horses, history of vaccination, seasonality, presence of wound/history of surgical procedures, clinical outcomes) and main clinical aspects (clinical signs, incubation period, length of hospitalization, and period between onset signs and hospitalization) in 70 cases of equine tetanus over 1990-2015, with emphasis in the association between these data and the clinical outcomes. High mortality rate (72.9%) was observed in this study. Forty (57.1%) horses presented history of wounds or surgical procedures related with tetanus, represented mainly by lesions in the hind limbs (42.5%), front limbs (15.0%), umbilical infections (7.1%), castration (4.3%), and face wounds (4.3%). Hyperesthesia, limb spasticity, cervical stiffness, tetanic spasms, and restriction of jaw movement were the main consistent clinical signs. Besides no statistical association, all the horses with umbilical infections, wounds in face, prolonged recumbency, sweating, dysphagia/aphagia died, and together with delay between onset of first clinical signs and prompt veterinary assistance (< 5 days) were considered indicative of poor prognosis; whereas there was a significant association (p=0.001) between survival and length of hospitalization > 7 days, seemed as an evidence of good prognosis. The high mortality rate of tetanus, even in horses under specific treatment, highlight the need for early diagnosis, prompt veterinary assistance, and establishment of prophylatic measures in equine farms.