Background and Aim: Contamination of meat with Salmonella could result in food-borne disease outbreaks among the consumers. However, there is a dearth of data assessing the presence of Salmonella in beef in Anambra State. Therefore, this study determined the prevalence and antimicrobial susceptibility of Salmonella in beef and slaughter/processing facilities in Kwata slaughterhouse. Materials and Methods: Swab samples (200) randomly collected were cultured for the isolation of Salmonella and the isolates subjected to antimicrobial susceptibility test. Data obtained were analyzed using t-test and analysis of variance with p< 0.05 considered statistically significant. Results: Of the 200 samples cultured, 33.5% (67/200) yielded Salmonella isolates. The mean Salmonella load (colony-forming unit [CFU]/cm2) for different contact surfaces (before and after contact with carcasses) was as follows: Slaughter floor, 1.1×1010±1.1×106a and 1.0×1010±1.1×106b; display table, 1.1×1010±11.1×106a and 1.0×1010±1.1×106b; washing bucket 1.01×1010±1.0×106a and 0.8×1010±0.1×106b; knife, 1.1×1010±1.10×106a and 1×1010±1.0×106b; boot, 1.1×1010±1.0×106a and 1.0×1010±1.10×106b; file, 1.1×1010±1.0×106a and 1.0×1010±0.1×106b; and wheelbarrow, 1.1×1010±1.0×106a and 1.01×1010±0.11×106b. Salmonella counts decreased significantly (p<0.05) in the presented order from slaughter floor to wheelbarrow after contact with carcasses. On the other hand, there was a significant (p<0.05) increase in washing water Salmonella counts before and after (0.7×1010±0.10×106a and 1.0×1010±1.0×106b CFU/100 ml) carcasses wash. To each of the antimicrobials tested, the percentage of the 67 isolates found resistant was as follows: ciprofloxacin, 25.4%; ofloxacin, 27%; ceftriaxone, 35.8%; amoxicillin/clavulanic acid, 88.1%; chloramphenicol, 59.7%; gentamicin, 34.3%; streptomycin, 49.3%; nalidixic acid, 49.3%; trimethoprim/sulfamethoxazole, 76%; nitrofurantoin, 89.6%; and ampicillin, 100%. Conclusion: Antimicrobial-resistant Salmonella were isolated from beef and slaughter/processing facilities in Anambra State. This underscores the need for a coordinated one health approach for the improvement of hygienic standard during slaughter/processing in the slaughterhouse surveyed, to limit meat contamination and hence safeguard human health.

The aim of this study was to investigate some biochemical and tissue changes associated with Salmonella gallinarum infection in laying hens (LHs), and the complicities of oxidative stress (OS). Fifty LHs were assigned to two groups of 25 LHs infected with S. gallinarum (10⁹ cfu*mL⁻¹ of S. gallinarum) and 25 uninfected controls. Biochemical assays and histopathology were carried out following standard procedures. There was a significant loss of body weight, drop in egg production, as well as 28% mortality in the infected group. Serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and superoxide dismutase (SOD) activities, as well as serum total protein, globulin, total cholesterol, total bilirubin, uric acid, creatinine and malondialdehyde (MDA) levels were significantly higher, whereas serum albumin levels were significantly lower in infected LHs. There were inflammatory, degenerative and necrotic changes observed in the affected organs. Considering the significant elevation in MDA levels coupled with elevated SOD activity in the infected LHs, OS may play a significant role in the pathology of fowl typhoid and may suggest a possible treatment of infected layers with antioxidants.

Background: Staphylococcus aureus is a major zoonotic and foodborne pathogen with substantial One Health implications, yet its prevalence, resistance, and virulence potential within the aquaculture sector in Nigeria remains poorly characterized. Objectives: To supplement existing information, this current study investigated the prevalence, clonal distribution, antimicrobial resistance, and virulence gene profiles of S. aureus isolates from fish, fish water, and occupationally exposed fish handlers in Anambra State, Southeast Nigeria. Methods: A total of 607 samples—comprising 465 surface swabs from raw and processed fish, 36 fish water samples, and 106 nasal swabs from fish handlers—were processed using selective culture, biochemical tests, antimicrobial susceptibility testing, DNA microarray analysis, spa typing, and SCCmec typing. Results: S. aureus was recovered from 16.5% (100/607) of the samples. Fourteen (14%) isolates were methicillin-resistant (MRSA), harboring mecA and SCCmec types IV and V, with a combined MRSA prevalence of 2.3%. Multidrug resistance was observed in 52.2% of isolates (mean Multiple Antimicrobial Resistance index: 0.23), with 19 resistance genes spanning nine antimicrobial classes—including heavy metal and biocide resistance. Twenty-eight spa types across 13 clonal complexes (CCs) were identified, with CC1, CC5, and CC8 predominating. The detection of shared spa types between fish and handlers indicates potential cross-contamination. Detected virulence genes included those for accessory gene regulators (agrI-IV), Pantone–Valentine leucocidin (lukFS-PV), toxic shock syndrome (tsst-1), hemolysins (hla, hlb, hld/hlIII, hlgA), biofilm formation (icaA, icaD), immune evasion (chp, scn, sak), enterotoxins (sea, seb, sec, sed, egc, and others), exfoliative toxins (etA, etB), epidermal cells differentiation (edinA, edinB), and capsular types (cap5, cap8). Conclusions: This study reveals that the aquaculture sector in Southeast Nigeria serves as a significant reservoir of genetically diverse, multidrug-resistant S. aureus strains with robust virulence profiles. These findings highlight the necessity of integrated One Health surveillance and targeted interventions addressing antimicrobial use and hygiene practices within aquatic food systems.

The effect of experimental Salmonella Gallinarum infection on the serum biochemistry of young pullets was assessed, and correlation was made with lesions in the target organs. 50 young pullets, at 7 weeks of age, were randomly assigned to 25 pullets infected orally with Salmonella Gallinarum (109 Salmonella Gallinarum colony forming units/mL) and 25 uninfected controls. Serum biochemical parameters were assayed following standard procedures, and selected body organs were processed for histopathology. There was a significant (p < .01) loss of body weight and an overall mortality of 36% in the infected pullets. The mean serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activities, as well as serum total protein, globulin, total cholesterol, total bilirubin, uric acid, and creatinine levels, were significantly (p < .05) higher in the infected pullets. Conversely, the mean serum albumin level was significantly (p < .05) lower in the infected pullets than the uninfected controls. Serum malondialdehyde levels, glutathione peroxidase, superoxide dismutase, and catalase activities of the infected pullets were significantly (p < .05) higher when compared with the controls. There were inflammatory, degenerative and necrotic changes observed in the affected organs. Some of the assayed basic biochemical parameters correlated strongly and significantly with malondialdehyde. It was concluded that infection of pullets with Salmonella Gallinarum caused significant alterations in serum biochemistry, induced oxidative stress, and by extension, inflammatory, degenerative and necrotic changes in the body organs. An association was established between glutathione peroxidase, superoxide dismutase, and catalase, which have antioxidant functions, and improved weight gain coupled with self-recovery. This finding underscores the need for the use of antioxidants in the therapeutic interventions during Salmonella Gallinarum infection of chickens.Cite this article as: Okafor, S., Ihedioha, J., & Ezema, W. (2025). Experimental salmonella gallinarum infection in young pullets: Correlation of serum biochemistry with organ pathology. Acta Veterinaria Eurasia, 51, 0090, doi: 10.5152/actavet.2025.24090v