During microbial assessment of cow milk cheese products in the city of Ilorin, Nigeria, a Listeria -like isolate was detected that could not be assigned to any known species. Whole-genome sequence analyses against all currently known 26 Listeria species confirmed that this isolate constitutes a new taxon within the genus Listeria , with highest similarity to Listeria costaricensis (average nucleotide identity blast of 82.66%, in silico DNA–DNA hybridization of 28.3%). Phenotypically, it differs from L. costaricensis by the inability to ferment sucrose, l-fucose and starch. The absence of haemolysis and Listeria pathogenic islands suggest that this novel species is not pathogenic for humans and animals. The name Listeria ilorinensis sp. nov. is proposed, with the type strain CLIP 2019/01311T (=CIP 111875T=DSM 111566T).

Inflammation is frequent at the site of injection in turkeys vaccinated with various commercial fowl cholera bacterins. Seven commercial and three laboratory bacterins were compared in 12week-old turkeys as to extent and severity of irritation with 3 routes of injection: subcutaneous, intradermal, and intramuscular. Commercial fowl cholera bacterins, particularly those with paraffin oil as the adjuvant, varied greatly in the irritation produced. The amount appeared consistent with the bacterin or adjuvant and somewhat independent of route of injection. The reaction to selected bacterins was comparable in 4-week-old turkeys to that in 12-weekolds. The reaction was usually less severe at 15 days postinjection than at 5 days. The intradermal route gave the most consistent results, probably because less bacterin diffused from the injection site, yet the amount of reaction was still not sufficiently consistent to be used quantitatively. Reaction to a given bacterin or adjuvant varied the most with the subcutaneous route.

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Background: Non-typhoidal Salmonella are major foodborne pathogens, posing serious challenges to public health and food safety worldwide. Salmonellosis in humans is commonly associated with the consumption of contaminated food, water, and direct contact with infected animals. This study aimed to characterize the distribution, diversity, virulence genotypes and antibiotic resistance of Salmonella enterica subsp. enterica serovar Nigeria, isolated from farm animals in north central Nigeria.Results: We recovered 9 different S. enterica ser. Nigeria isolates from our sampling, eight from pig and one from chicken. The antimicrobial susceptibility testing against 15 antimicrobial agents showed variable resistance profiles. Whole genome sequence (WGS) analysis revealed that all 9 isolates contained a single mutation parC (T57S) substitution in addition to qnrB19, expected to confer decreased susceptibility to ciprofloxacin and tet(A) expected to confer resistance to tetracycline. Furthermore, two plasmid targets were also detected in all the strains, Col(pHAD28) and IncQ1. MLST analysis showed that all 9 isolates exhibited only one sequence type, (ST-4911) irrespective of the source of isolation. A SNP-based phylogeny indicates that the 9 isolates are highly related and lack other close relatives in the pathogen detection database.Forty core (housekeeping) and accessory virulence genes were identified from different virulence loci including Salmonella Pathogenicity Islands, virulence associated plasmids (pSV), chromosomes and fimbriae. Conclusion: This study provided valuable information on the resistance determinants, virulence genes, phenotypic resistance profiles, plasmids and multilocus sequence typing (MLST) of Salmonella Nigeria from food animals by WGS. Highlighting the significance of poultry and pig to the spread and emergence of Salmonella Nigeria in this region of Nigeria, therefore, there is the need for consumer's education and enlightenments on the importance of proper handling and preparation of food, this will reduce the potential risk of transmission of this pathogen.

Poultry salmonellosis caused by Salmonella enterica is one of the most important bacterial diseases posing serious challenges to poultry production and human health worldwide. This study investigated the occurrence, serotypes, multilocus sequence types (MLSTs), antimicrobial resistance, plasmids, and 12 selected virulence genes of non-typhoidal Salmonella from poultry layer farms using whole-genome sequencing (WGS) methods. Two hundred cloaca swab samples were aseptically collected from four commercial poultry farms (layers) and transferred in sterile universal bottles on ice to the laboratory for analysis. Presumptive Salmonella isolates were detected with selective media and conventional biochemical tests. Serovars were confirmed by serotyping using the slide agglutination and Seqsero methods. Seven samples were positive for Salmonella consisting of Salmonella Typhimurium (S. Typhimurium) (n = 4), S. Albany (n = 2), and S. Agama with an occurrence rate of 3.5 % (7/200). Overall, 3 isolates showed the parC mutation expected not to cause resistance. Similarly, one S. Typhimurium isolate carried plasmid replicons of IncFIB(S)/IncFII(S) type without antimicrobial resistance genes. Three sequence types (STs); 19 (S. Typhimurium), 5317 (S. Albany), and 467 (S. Agama) were obtained. Salmonella Agama harboured 12 virulence genes, while S. Typhimurium and S. Albany harboured 11 virulence genes each. This study highlights the importance of S. Typhimurium, S. Albany, and S. Agama as major pathogens associated with poultry farms in Ilorin, north-central Nigeria. It equally provided baseline information on the serovar distribution, STs, resistance and the virulence gene profiles of all the serovars. Therefore, chickens can serve as a potential source of Salmonella transmission to humans, and this constitutes a potential health risk to the human population. Hence, there is a need for a specific Salmonella control program to be instituted as part of a national food safety strategy.