Spotty liver disease (SLD) affects free-range laying hens, leading to mortality and reduced egg production. Campylobacter species, including Campylobacter hepaticus, have been associated with SLD cases worldwide. However, the cause of SLD-like lesions found in broilers in Japan still remains unclear. The present study aimed to investigate the involvement of Campylobacter spp. in broiler SLD by conducting microbiological, molecular biological, serological, histopathological, and immunohistopathological examinations using specimens of liver, bile, cecum, and serum from SLD-like and non-SLD chickens. C. jejuni was predominantly isolated and detected in approximately 40% of both non-SLD livers and SLD-like livers, with no significant difference between them. However, C. hepaticus was neither isolated nor detected in this study. Gross and histopathology revealed multifocal necrotizing hepatitis, suppurative granulomatous hepatitis, and cholangiohepatitis. Hepatitis stages are classified as no hepatitis, subclinical, acute, and chronic hepatitis. C. jejuni was more frequently present in acute-stage SLD-like livers, and high IgG antibody levels were noted in both subclinical and SLD-like-affected chickens, indicating C. jejuni infection. Immunohistochemical examination also supported these findings. The findings suggest that C. hepaticus was not involved in SLD-like in broilers in Japan, but C. jejuni translocation from the intestines to the liver may be a contributing factor.

Spotty liver disease (SLD) affects free-range laying hens, leading to mortality and reduced egg production. Campylobacter species, including a novel strain, Campylobacter hepaticus, have been associated with SLD cases worldwide. However, the cause of SLD like lesions found in broilers in Japan is still remains unclear. The present study aimed to investigate the involvement of Cam-pylobacter spp. in broiler SLD by conducting microbiological, molecular, serological, histopatho-logical, and immunohistopathological examinations using specimens of liver, bile, cecum, and serum from SLD-like and non-SLD chickens. C. jejuni was predominantly isolated and detected in approximately 40% of both non-SLD livers and SLD-like livers, with no significant difference between them. While C. hepaticus was neither isolated nor detected in this study. Gross and his-topathology revealed multifocal necrotizing hepatitis, suppurative granulomatous hepatitis, and cholangiohepatitis. Hepatitis stages classified as no hepatitis, subclinical, acute, and chronic hepatitis. C. jejuni was more frequently present in acute-stage SLD-like livers, and high IgG an-tibody levels were noted in both subclinical and SLD-like-affected chickens, indicating C. jejuni infection. Immunohistochemical also supported these findings. The findings suggest that C. he-paticus was not involved in SLD-like in broilers in Japan, but C. jejuni translocation from the in-testines to the liver may be a contributing factor.

Akahoya is a volcanic soil rich in alumina, primarily deposited in Kyushu, Japan. We have found that Akahoya adsorbs bacteria in the water surrounding cattle grazing areas, suggesting a potential for environmental purification. This study investigated the spectrum of microorganisms adsorbed by Akahoya using a column filled with Akahoya through which a suspension of microorganisms was passed. Shirasu soil, another volcanic soil with a different chemical composition, was used as a control. Akahoya effectively adsorbed a diverse range of microorganisms including Escherichia coli , Campylobacter jejuni , Vibrio parahaemolyticus , Salmonella Enteritidis, Staphylococcus aureus , Clostridium perfringens , spores of Bacillus subtilis and Bacillus anthracis , severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), murine norovirus, and avian influenza virus (H3N2), whereas Shirasu soil did not adsorb any of the organisms examined. Moreover, bacteria naturally present in river water, such as aerobic bacteria, total coliforms, and Enterobacteriaceae as indicators of river contamination, as well as E. coli added artificially to sterilized river water, were reduced to below the detection limit (<1 CFU/mL) after being passed through Akahoya. Additionally, the number of viable E. coli continued to decrease after contact with Akahoya for 1 month, suggesting bactericidal effects. Notably, the adsorption of E. coli to Akahoya was influenced by the concentration of phosphate and the pH of the suspension due to the interaction between the surface phosphorylation of organisms and Al ₂ O ₃ , the major chemical component of Akahoya. The present results demonstrate the remarkable ability of Akahoya to remove phosphate and microbes, suggesting that Akahoya could be used for water purification processes. IMPORTANCE: Although a safe and sufficient water supply is essential for the maintenance of hygienic conditions, a major challenge is to develop a comprehensive effective, sustainable, and cost-effective technological approach for the treatment and purification of contaminated water. In this study, we demonstrated that a novel volcanic soil, Akahoya, which has unlimited availability, is a highly effective adsorbent for a wide range of bacterial and viral pathogens, suggesting its potential as a sustainable resource for this purpose. It was suggested that the adsorption of microorganisms on Akahoya was mediated by phosphate groups present on the surface structures of microorganisms, which bind to the alumina component of Akahoya according to the phosphate concentration and pH of the liquid phase. The present findings highlight the exceptional ability of Akahoya to eliminate or reduce phosphate and microorganisms effectively in water purification processes, thus contributing to the development of efficient and sustainable solutions for addressing water pollution challenges.