Veterinary microbiology最新文献

{"title":"Diagnosis of Mycobacterium leprae in free-living animals in a hyperendemic area in Brazil","authors":"Beatriz Silva Nogueira ,&nbsp;Maerle Oliveira Maia ,&nbsp;Fernanda Harumi Maruyama ,&nbsp;Thaís Rabelo dos Santos-Doni ,&nbsp;Edson Moleta Colodel ,&nbsp;Richard de Campos Pacheco ,&nbsp;Luciano Nakazato ,&nbsp;Valéria Dutra","doi":"10.1016/j.vetmic.2025.110408","DOIUrl":"10.1016/j.vetmic.2025.110408","url":null,"abstract":"<div><div><em>Mycobacterium leprae</em> (<em>M. leprae</em>) is a globally distributed intracellular pathogen that causes human leprosy. For many years, <em>M. leprae</em> has been considered a human-only pathogen. However, the discovery of infected armadillos (<em>Dasypus novemcinctus</em>) has led to studies into its presence in animals. Many questions regarding leprosy remain unanswered, such as the epidemiological role of the environment and animals in maintaining of the disease. Thus, the objective of this study was to identify <em>M. leprae</em> in wild animals in Brazil. Samples from 105 wild animals of different species were analyzed using polymerase chain reaction of the RLEP region to detect <em>M. leprae</em> in biological samples. <em>M. leprae</em> was detected in 13 samples (12.3 %) from animals in the orders Artiodactyla, Carnivora, Cingulata, Pilosa, Primates and Rodentia. Eight samples were sequenced and they had 100 % identity to microorganisms of the same species. This study identified different species of wild animals infected with <em>M. leprae</em> in a region hyperendemic for leprosy, demonstrating that these animals may play important roles in the epidemiology and in maintaining the disease.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110408"},"PeriodicalIF":2.4,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143075726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recombinant nanobody expressed by transgenic chimeric chickens eliminated vertical transmission of avian leukosis virus subgroup J","authors":"Jiahua Liang ,&nbsp;Ke Qin ,&nbsp;Ning Xiao ,&nbsp;Yingying Zhao ,&nbsp;Ruiying Han ,&nbsp;Jinhan Wang ,&nbsp;Jiahan Liu ,&nbsp;Huicheng Lu ,&nbsp;Xiaoli Wang ,&nbsp;Fuxian Yu ,&nbsp;Xiaochuan Tang","doi":"10.1016/j.vetmic.2025.110407","DOIUrl":"10.1016/j.vetmic.2025.110407","url":null,"abstract":"<div><div>Because of the vertical transmission of avian leukosis virus subgroup J (ALV-J), control of ALV-J in breed of chicken is still a serious issue. Blocking vertical transmission using antibodies is a potential strategy, but its high cost limits its application. We artificially designed recombinant nanobody (Nb) and efficiently expressed and secreted them in three primary chicken cells cultured in vitro by adenovirus delivery. We found that secreted the Nb could reduce the infection of cells by ALV-J. Moreover, we prepared transgenic chimeric chickens expressing Nb and found that the Nb reduced the infection and vertical transmission of ALV-J to chickens. In particular, transgenic chimeric hens expressing high concentration of the Nb eliminated vertical transmission of the virus. Collectively, current study provides new avenues for the control of ALV-J transmission.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110407"},"PeriodicalIF":2.4,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143053586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of foot-and-mouth disease virus on memory T and B cell populations in swine","authors":"Wei Zhao ,&nbsp;Jia Su ,&nbsp;Qinghong Xue ,&nbsp;Jie Gao ,&nbsp;Hongxu Bai ,&nbsp;Yueyi Gao ,&nbsp;Xiaochun Chen ,&nbsp;Weijie Liu ,&nbsp;Dongdong Liu ,&nbsp;Guohua Wang ,&nbsp;Xiangmei Zhou","doi":"10.1016/j.vetmic.2025.110406","DOIUrl":"10.1016/j.vetmic.2025.110406","url":null,"abstract":"<div><div>Foot-and-mouth disease virus (FMDV) is a highly contagious picornavirus that poses a serious threat to the global livestock industry. This study aimed to investigate the impact of FMDV infection on the memory immune response in pigs and to analyze the role of type II interferon (IFN-γ) in this process. By comparing pigs artificially infected with FMDV and those vaccinated with inactivated FMDV vaccine, we found that FMDV infection significantly suppressed the development of memory T helper (Th) and B cell populations, affecting the memory immune response. Further experiments showed that pretreatment with IFN-γ could counteract the immunosuppression caused by FMDV, and this counteraction was achieved by promoting the expression of three transcription factors: T-bet, Eomes, and Bcl-6. Our findings emphasize the key role of IFN-γ in regulating the host's immune response to FMDV infection and provide new scientific evidence for the development of effective FMDV vaccines.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110406"},"PeriodicalIF":2.4,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143145620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiological surveillance of myxoma virus in European hares (Lepus europaeus) in the Iberian Peninsula: First evidence of infection by the emerging ha-MYXV","authors":"Beatriz Cardoso ,&nbsp;Sabrina Castro-Scholten ,&nbsp;Roser Velarde ,&nbsp;Salvador Rejón-Segura ,&nbsp;Remigio Martínez ,&nbsp;Ana M. Lopes ,&nbsp;Lorena Pereira ,&nbsp;Kevin P. Dalton ,&nbsp;Andrea Menéndez-Manjón ,&nbsp;Josep Estruch ,&nbsp;Vanesa Alzaga ,&nbsp;Jacinto Román ,&nbsp;Juan José Luque-Larena ,&nbsp;François Mougeot ,&nbsp;Carlos Rouco ,&nbsp;Ignacio García-Bocanegra","doi":"10.1016/j.vetmic.2025.110405","DOIUrl":"10.1016/j.vetmic.2025.110405","url":null,"abstract":"<div><div>We investigated the circulation of myxoma viruses (MYXV) in European hare (<em>Lepus europaeus</em>) populations from Spain. A total of 140 individuals were sampled through passive and active surveillance from 2018 to 2024. Myxoma virus DNA was confirmed in two out of 114 (1.8 %, CI 95 %=0.2–6.2) hares analysed by PCR. One was infected with the classic MYXV strain, and the other with the recombinant ha-MYXV strain. This is the first report of ha-MYXV infection in a European hare. A commercial indirect ELISA detected antibodies against MYXV in 3.2 % (4/126; CI 95 %=0.9–7.9) of animals tested. Both molecular and serological results suggest occasional transmissions of MYXV from sympatric European rabbits (<em>Oryctolagus cuniculus</em>) and/or Iberian hares (<em>Lepus granatensis</em>) to European hares. These sporadic infections appear to be scattered across time and space, predominantly in areas where lagomorph species overlap. Because European hares appear to be immunologically naïve to MYXV, another recombination event could have a significant impact on populations, similar to what occurred with Iberian hares. This study highlights the importance of enhancing our understanding of MYXV epidemiology in wild lagomorph species through large-scale monitoring efforts.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110405"},"PeriodicalIF":2.4,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143075727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recombinant probiotic Escherichia coli delivers the polymeric protein of swine influenza virus for protection","authors":"Jin-Mei Sun,&nbsp;Wen-Qiang Zhang,&nbsp;Yan-Jin Li,&nbsp;Tian-Kui Guo,&nbsp;Rong-Rong Zhang,&nbsp;Yong-Lei Yang,&nbsp;Ying Zhao,&nbsp;Ling-Jiao Yu,&nbsp;Chun-Wei Shi,&nbsp;Gui-Lian Yang,&nbsp;Hai-Bin Huang,&nbsp;Yan-Long Jiang,&nbsp;Jian-Zhong Wang,&nbsp;Xin Cao,&nbsp;Nan Wang,&nbsp;Yan Zeng,&nbsp;Wen-Tao Yang,&nbsp;Chun-Feng Wang","doi":"10.1016/j.vetmic.2025.110401","DOIUrl":"10.1016/j.vetmic.2025.110401","url":null,"abstract":"<div><div>Swine influenza virus invades the host through the respiratory mucosa, which severely restricts the development of the pig breeding industry. To construct monomeric and trimeric vaccines, we developed recombinant <em>Escherichia coli</em> Nissle 1917 (EcN) strains that express the receptor binding site (RBS) of the hemagglutinin (HA) antigen from H1N1 swine influenza virus. After the mucosal immunization of mice, we found that probiotics activated CD40 and CD86 in DCs and increased the levels of IL-4 and IFN-γ secretion by T cells. Furthermore, the probiotics improved the function of the mucosal immune system, increased the level of SIgA, level of IgG and number of B220⁺IgA⁺, and activated germinal center B cells. The challenge experiment revealed that the probiotics alleviated weight loss, reduced pathological injury to the lungs, and protected the mice from virus infection. We also observed that the serum neutralizing antibodies of immunized piglets significantly increased, which reduced the shedding frequency of swine influenza virus in the nose of the piglets and reduced the pathological damage by activating the T cell immune response in infected piglets. Thus, the constructed probiotics are promising candidates for effective non-traditional swine influenza vaccines.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110401"},"PeriodicalIF":2.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of UPWr_E124 phage cocktail for effective reduction of avian pathogenic Escherichia coli in mice and broiler chickens","authors":"David Sáez Moreno ,&nbsp;Maciej Kuczkowski ,&nbsp;Paweł Korzeniowski ,&nbsp;Krzysztof Grzymajło ,&nbsp;Anna Woźniak-Biel ,&nbsp;Paulina Śliwka ,&nbsp;Anita Rywińska ,&nbsp;Marta Kuźmińska-Bajor","doi":"10.1016/j.vetmic.2025.110398","DOIUrl":"10.1016/j.vetmic.2025.110398","url":null,"abstract":"<div><div>Avian pathogenic <em>Escherichia coli</em> (APEC) is the main causative agent of colibacillosis, causing poultry respiratory infections, mortality and economic loss. APEC poses a serious threat to public health and food safety due to its multi-drug resistance and capacity to form biofilms. Bacteriophages (phages) have emerged as an alternative to antibiotics. To cure APEC-infected chickens, a cocktail consisting of UPWr_E1, UPWr_E2 and UPWr_E4 APEC-specific phages was developed and tested. In this study, we documented the maintenance of their activity in neutralized simulated gastric fluid (SGF) conditions and the efficiency of the UPWr_E124 phage cocktail in inhibiting APEC in biofilm structures on chicken breast meat surfaces. Further, we evaluated the efficacy of the UPWr_E124 phage cocktail against APEC <em>in vivo</em> in murine and chicken infection models. In experimentally infected mice, we evaluated the intraperitoneal and gastric gavage administrations of phages. The study revealed that gastric administration of phages reduced bacterial levels in the respiratory system. Moreover, we tested the UPWr_E124 phage cocktail in a chicken model of infection, where phages effectively reduced the number of APEC in the lungs, bursa of Fabricius and blood. These results suggest that the UPWr_E124 phage cocktail could be a potential treatment for colibacillosis in the poultry industry.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110398"},"PeriodicalIF":2.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143068236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natural infection and diversity of hemotropic mycoplasmas in free-ranging Geoffroy’s cat (Leopardus geoffroyi) and margay cat (Leopardus wiedii) populations in Southern Brazil","authors":"Ugo Araújo Souza ,&nbsp;Laura Berger ,&nbsp;Renata Fagundes-Moreira ,&nbsp;Vinícius Baggio-Souza ,&nbsp;Adeyldes Reis ,&nbsp;Rafaela Mallmann-Bohn ,&nbsp;Aline Girotto-Soares ,&nbsp;Felipe Bortolotto Peters ,&nbsp;Marina Ochoa Favarini ,&nbsp;Ana Paula M. Albano ,&nbsp;Silvia Resende Terra ,&nbsp;Anelise Webster ,&nbsp;Bruno Dall’Agnol ,&nbsp;Bruno Albuquerque de Almeida ,&nbsp;Tatiane Campos Trigo ,&nbsp;Stella de Faria Valle ,&nbsp;Flávia Pereira Tirelli ,&nbsp;José Reck ,&nbsp;João Fabio Soares","doi":"10.1016/j.vetmic.2025.110396","DOIUrl":"10.1016/j.vetmic.2025.110396","url":null,"abstract":"<div><div>Hemoplasma infection significantly impacts felines health, yet there is a research gap regarding free-ranging wild small felids. Therefore, this study aimed to investigate the occurrence of hemoplasma in <em>Leopardus geoffroyi</em> and <em>Leopardus wiedii</em> in southern Brazil. For this purpose, we conducted molecular research for <em>Mycoplasma</em> spp. based on the 16S rRNA gene in 79 blood samples from captured wild felids. When positive, the samples were submitted to species-specific reactions for <em>Mycoplasma haemofelis</em> (<em>Mhf</em>), ‘<em>Candidatus</em> Mycoplasma haemominutum’ (<em>C</em>Mhm), and ‘<em>Candidatus</em> Mycoplasma turicensis’ (<em>C</em>Mt). A total of 39/79 samples were positive for at least one species of hemoplasma. The frequencies found by hemoplasma species were: 39.2 % (31/79) for <em>Mhf</em>, 17.7 % (14/79) for <em>C</em>Mhm, and 20.2 % (16/79) for <em>C</em>Mt. Factors such as species, sex, age, pelage, capture season, ectoparasite presence, and co-infection with another <em>Mycoplasma</em> were not associated with hemoplasma infection. This study provides the first evidence of circulating hemotropic mycoplasmas in free-living <em>L. geoffroyi</em> and <em>L. wiedii</em> in southern Brazil.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110396"},"PeriodicalIF":2.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wall teichoic acid glycosylation of bovine-associated Staphylococcus aureus strains","authors":"Catharina E. Exel ,&nbsp;Sara M. Tamminga ,&nbsp;Sandra Man-Bovenkerk ,&nbsp;A. Robin Temming ,&nbsp;Astrid Hendriks ,&nbsp;Mirlin Spaninks ,&nbsp;Nina M. van Sorge ,&nbsp;Lindert Benedictus","doi":"10.1016/j.vetmic.2025.110403","DOIUrl":"10.1016/j.vetmic.2025.110403","url":null,"abstract":"<div><div><em>Staphylococcus aureus</em> (<em>S. aureus</em>) is one of the major causes of bovine mastitis, a disease with detrimental effects on health and wellbeing. Current control measures are costly, laborious and not always effective in eradicating <em>S. aureus</em>. The cell wall-linked polysaccharide wall teichoic acid (WTA) is highly immunogenic in humans and is considered as a prospective vaccine antigen based on promising pre-clinical studies in animals. WTA consist of polymerized ribitol-phosphate backbone that is modified with N-acetylglucosamine (GlcNAc) moieties in different configurations by the glycosyltransferases TarS (β−1,4-GlcNAc), TarM (α−1,4-GlcNAc) and TarP (β−1,3-GlcNAc). This study aimed to characterize the presence and genetic variation in <em>tarS</em>, <em>tarM</em> and <em>tarP</em> in bovine-associated <em>S. aureus</em> strains and how this impacts WTA-glycoprofile. Bioinformatic analyses of a whole genome sequence database consisting of 1047 <em>S. aureus</em>, 10 <em>S. schweitzeri,</em> and 6 <em>S. argenteus</em> strains showed that over 99<em>%</em> of strains contained <em>tarS</em>, 34 % also contained <em>tarM</em>, while 5 % of the strains encoded <em>tarP</em> in addition to <em>tarS.</em> The distribution of WTA-glycosyltransferase genes was similar to what has been reported for human-associated <em>S. aureus</em> strains. Phenotypic analysis of WTA glycosylation by flow cytometry corroborated with <em>tarS/tarM/tarP</em> gene presence. The WTA glycoprofile was variable between bovine-associated strains and the levels and ratios of GlcNAcylation were affected by growth conditions. Interestingly, a divergent <em>tarM</em> allele was present in strains of clonal complexes (CC) 49 and the mastitis-associated CC151, but its function was similar to canonical <em>tarM</em>. In conclusion, we demonstrated that bovine-associated <em>S. aureus</em> strains show similar variation in WTA GlcNAc decoration as human <em>S. aureus</em> strains, despite the presence of a divergent <em>tarM</em> allele.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110403"},"PeriodicalIF":2.4,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143024739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BTG3 inhibits porcine epidemic diarrhea virus replication by promoting viral S2 protein degradation through the autophagy and proteasome pathways","authors":"Qingxiao Zhu ,&nbsp;Tian Liu ,&nbsp;Wenzhen Qin ,&nbsp;Xinyu Yang ,&nbsp;Wu Tong ,&nbsp;Hai Yu ,&nbsp;Hao Zheng ,&nbsp;Guangzhi Tong ,&nbsp;Tongling Shan ,&nbsp;Yu Zhang ,&nbsp;Xuelan Liu ,&nbsp;Ning Kong","doi":"10.1016/j.vetmic.2025.110402","DOIUrl":"10.1016/j.vetmic.2025.110402","url":null,"abstract":"<div><div>BTG3, which belongs to the BTG/Tob gene family, is involved in various physiological processes. Infection with porcine epidemic diarrhea virus (PEDV), an alphacoronavirus, is associated with high mortality rates among piglets, contributing to major economic losses. This study elucidated a novel mechanism through which BTG3 suppresses PEDV replication. Endogenous BTG3 protein expression was upregulated in PEDV-infected host cells. PEDV replication was suppressed upon BTG3 overexpression but enhanced upon BTG3 knockdown. Additionally, BTG3 inhibited viral proliferation by targeting and degrading the S2 subunit of the PEDV spike (S) protein through both autophagy and proteasome pathways. BTG3 interacted and co-localized with the S2 protein, promoting S2 protein degradation through the recruitment of the cargo receptor NDP52 and the E3 ubiquitin ligase MARCHF8. In summary, this study elucidated a novel antiviral mechanism in which the host BTG3 targeted the viral S2 protein to inhibit PEDV proliferation through autophagy and proteasome pathways. These findings indicate that BTG3 is a potential novel target for the prevention and control of PEDV.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110402"},"PeriodicalIF":2.4,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143024733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced virulence of Acinetobacter johnsonii at low temperatures induces acute immune response and systemic infection in American bullfrogs (Aquarana catesbeiana)","authors":"Han Lin ,&nbsp;Jingyang Sun ,&nbsp;Hua Li ,&nbsp;Kesong Chen ,&nbsp;Zhendong Qin ,&nbsp;Biao Jiang ,&nbsp;Wei Li ,&nbsp;Qing Wang ,&nbsp;Youlu Su ,&nbsp;Li Lin ,&nbsp;Chun Liu","doi":"10.1016/j.vetmic.2025.110404","DOIUrl":"10.1016/j.vetmic.2025.110404","url":null,"abstract":"<div><div><em>Acinetobacter johnsonii</em> is a denitrifying bacterium commonly used as an environmental probiotic in wastewater treatment. However, research on its potential pathogenicity to animals is limited. During an epidemiological survey conducted from 2022 to 2024 at bullfrog farms in Guangdong Province, China, multiple strains were isolated from diseased bullfrogs during the low-temperature season. Three representative strains were selected for virulence testing, which showed high virulence to bullfrogs. Molecular identification confirmed these strains as <em>A. johnsonii</em>. One strain was named NW220314S and chosen for further study. Artificial infection through different routes revealed that the mortality rate of bullfrogs infected with this strain was higher at 15°C compared to 28°C. Additionally, the expression of at least 11 virulence genes was significantly higher at 15°C. Pathological examinations of bullfrogs infected with <em>A. johnsonii</em> showed systemic infection with extensive infiltration of inflammatory factors in organs, muscles, and skin. Immune-related gene expression analysis indicated a rapid and intense inflammatory response in bullfrogs post-infection. Our findings uncovered the novel phenomenon of the pathogenicity of <em>A. johnsonii</em> in bullfrogs under low-temperature conditions, warning of the potential threat of A. johnsonii to amphibian populations and the risks associated with its use in various environmental applications.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"302 ","pages":"Article 110404"},"PeriodicalIF":2.4,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143060884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}