The presence of contaminated animals in wildlife rehabilitation centers poses a threat for both animals and humans that come into contact with them or the contaminated environment. The aim of this study was to assess the presence of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), as well as studying the biofilm formation capacity of these isolates, Yersinia enterocolitica, Salmonella enterica and Campylobacter spp. in wild animals from a rehabilitation center. During a two-year period, feces were collected from animals that were admitted to a wildlife rehabilitation center (n=324 samples). The pathogens were isolated from 51 (15.7%) animals of different species of mammals, birds and reptiles. Forty isolates (12.3%) were identified as S. aureus, of these, 32 (9.9%) were identified as MRSA and 72.5% were able to form biofilm. Y. enterocolitica was found in five mammals (5.1%), three reptiles (21.43%) and two birds (0.94%). Salmonella and Campylobacter were isolated from one bird each (0.67% and 0.67%, respectively). A wide diversity of animal species in rehabilitation centers, including birds, mammals and reptiles, can carry MRSA and enterobacteria of one health concern and eliminate in the feces. The presence of these pathogens in the gastrointestinal tract of wild animals admitted to a wildlife rehabilitation center shows the importance of microbiological monitoring of animals at the time of their admission and reinforces the need for specific hygienic-sanitary care.

Senecavirus A (SVA) is a picornavirus that is endemic in swine, causing a vesicular disease clinically indistinguishable from other vesicular diseases, like foot-and-mouth disease. The widespread viral circulation, constant evolution, and economic losses caused to the swine industry emphasize the need for measures to control the agent. In this study, we evaluated the immunogenicity of a whole-virus-inactivated vaccine using a representative contemporary Brazilian SVA strain in Balb/ByJ mice. The animals were vaccinated with two doses by an intramuscular route. The humoral response induced by the vaccination was evaluated by an in-house ELISA assay for IgG detection. The cellular response was assessed by flow cytometry after in vitro SVA stimulation in splenocyte cultures from vaccinated and non-vaccinated groups. Protection against SVA was assessed in the experimental groups following an oral challenge with the homologous virus. The vaccination induced high levels of IgG antibodies and the proliferation of CD45R/B220⁺sIgM⁺, CD3e⁺CD69⁺, and CD3e⁺CD4⁺CD44⁺CD62L⁻ cells. These results indicate the immunogenicity and safety of the vaccine formulation in a murine model and the induction of humoral and cellular response against SVA.

Fowl adenoviruses (FAdVs) are important pathogens affecting poultry worldwide. Different serotypes cause distinct disease syndromes in domestic chickens, including gizzard erosions (GE), inclusion body hepatitis (IBH), and hepatitis-hydropericardium syndrome (HHS). Despite the economic impact, the evaluation of pathogenicity and genomic features of Brazilian isolates has not yet been assessed. This study aimed to investigate the pathogenic characteristics and whole-genome features of two FAdV Brazilian isolates, BRMSA3762 (FAdV-1) and BRMSA3761 (FAdV-11). For this, pathogenicity was evaluated through inoculation of day-old specific-pathogen-free chickens and embryos. Infected birds were macroscopically and histologically examined in trachea, heart, proventriculus, gizzard, liver, pancreas, duodenum, kidney, and bursa of Fabricius. Also, we analyzed viral distribution in tissues and cloacal virus shedding through real-time PCR. Furthermore, whole-genome sequencing enabled phylogenetic reconstruction and recombination analyses. Results revealed that FAdV-1 was pathogenic, causing severe erosions in the gizzard and a slight alteration in the heart tissue, while FAdV-11 exhibited higher virulence and affected several tissues, including pancreas, liver, gizzard, bursa, and heart. Both viruses were detected in all tissues 8 days post-inoculation, and viral excretion through cloaca occurred throughout the entire experimental period. Differences were established in viral titers, with FAdV-11 demonstrating a higher viral load in tissues and cloacal shedding. In addition, both isolates demonstrated to be pathogenic in SPF chicken embryos. Genomic analysis revealed that BRMSA3762 clustered with sequences from other countries in the Americas, showing no evidence of recombination. Surprisingly, BRMSA3761 clustered with sequences isolated in Europe and the Middle East and was identified as a putative recombinant showing a genetic arrangement closely related to Iranian and Lebanese sequences. Collectively, our findings provide important insights into the pathogenicity of Brazilian fowl adenovirus isolates and contribute to the current understanding of their genetic diversity.