Salmonella Typhimurium infection in pigs is characterized by an intense inflammatory response in early infection which seems to dysregulate host physiology including the gut microbiota. Both, changes in host physiology and microbiome composition, must entail modifications within the gut environment. This study analyzes the gut metabolome in early infected pigs (48 hours after infection) and non-infected controls by untargeted metabolomics (LC–QTOF MS/MS and GC–TOF MS), supported with microbiome data (16S rRNA abundance and prediction functional analyses). The metabolomic profile in Salmonella-infected pigs differed from healthy controls in 39 of these metabolites, including eight amino acids, four bile acids and carboxylic acids, three carnitines and sugar derivates, eleven fatty acids and six other compounds. Changes in amino acids abundance and the observed decrease of proteolytic bacteria such as Lactobacillus or Bacteroides could favor the niche colonization by Desulfovibrionaceae. In addition, the decrease in short chain fatty acids and tricarboxylic acids cycle was correlated to a decrease in beneficial bacteria in infected pigs. Interestingly, we observed an increase of bile acids concentration and compounds such as succinic acid or pantothenic acid, which may boost the inflammatory response. Altogether, the results reveal how S. Typhimurium infection alters the gut microbiome composition and prompts changes in the metabolism with a potential interaction between intestinal metabolism and microbiota abundance.

Antibiotic inefficacy in treating bacterial infections is largely studied in the context of developing resistance mechanisms. However, little attention has been paid to combined diseases mechanisms, interspecies pathogenesis and the resulting impact on antimicrobial treatment. This review will consider the co-infections of Salmonella and Schistosoma mansoni. It summarises the protective mechanisms that the pathophysiology of the two infections confer, which leads to an antibiotic protection phenomenon. This review will elucidate the functional characteristics of the gut microbiota in the context of these co-infections, the pathogenicity of these infections in infected mice, and the efficacy of the antibiotics used in treatment of these co-infections over time. Salmonella-Schistosoma interactions and the mechanism for antibiotic protection are not well established. However, antimicrobial drug inefficacy is an existing phenomenon in these co-infections. The treatment of schistosomiasis to ensure the efficacy of antibiotic therapy for bacterial infections should be considered in co-infected patients.

The sustainability of agroecological systems, biodiversity protection, animal welfare and consumer demand for higher-quality products from alternative and extensive farming methods, have reinforced interest in local breeds that are well adapted to low-input environments. However, food safety needs to be safeguarded to reinforce consumer confidence. The aim of this study was to conduct a preliminary investigation on the occurrence of Salmonella spp. in eggshells, hen’s cloaca and litter materials from autochthonous Portuguese laying hens raised in a semi-extensive system for small-scale production. A total of 279 samples were obtained, with 63 samples from the “Preta Lusitânica” breed, and 72 samples each from the remaining autochthonous breeds, namely “Branca”, “Amarela” and “Pedrês Portuguesa”. None (0%) of the samples analyzed were positive for Salmonella spp.. To the best of our knowledge, these are the first results of Salmonella evaluation from hen’s cloaca, eggshells, and litter materials in autochthonous Portuguese chickens, suggesting that a semi-extensive production system can contribute to better food security and a lower risk to public health and the environment.

An outbreak of esophagitis and ingluvitis caused by Salmonella Typhimurium in passerines seized from illegal wildlife trafficking is described. This illegal activity causes stress and leads to lowered immunity in the birds. Additionally, inadequate hygiene conditions predispose the birds to diseases such as salmonellosis. Few studies report the occurrence of Salmonella-induced lesions in the esophagus and crop of wild birds; thus, this study aimed to describe the disease in these species, investigate its presence in the environment, and determine the antimicrobial resistance profile. Three birds of the genus Sporophila were necropsied. In the esophagus and crop, yellowish plaques corresponding to necrosis with bacterial aggregates were observed. Salmonella spp. was isolated from these lesions, with genus confirmation via MALDI-TOF. Environmental samples were collected from the enclosures and cages where the animals were quarantined, and the same bacterium was isolated. In two birds, the serotype S. Typhimurium was identified. Antibiograms performed on the strains from the birds and the environment revealed resistance to antibiotics in the classes of Penicillins, Sulfonamides, Aminoglycosides, Monobactams, Tetracyclines, and first and third-generation Cephalosporins. To the authors' knowledge, this is the first report of this agent causing death in Sporophila due to esophagitis and ingluvitis. It is also the first report of salmonellosis in three species of passerines in Brazil. The study underscores the importance of understanding the pathogens circulating in wild animals, especially within the context of One Health.