Diseases of aquatic organisms最新文献

Evaluation of Candidatus Xenohaliotis californiensis (CXc) and its associated phage pCXc in black abalone of Baja California, Mexico. 墨西哥下加利福尼亚州黑鲍鱼中加利福尼亚候选菌（CXc）及其伴生噬菌体pCXc的鉴定。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-07-17 DOI: 10.3354/dao03860

Casandra Delgadillo-Anguiano, Fabiola Lafarga-De la Cruz, Julio Lorda, Carmen E Vargas-Peralta, Gabriela Montaño-Moctezuma, Beatriz Ibarra-Macías, Rodrigo Beas-Luna, Alicia Abadía-Cardoso

{"title":"Evaluation of Candidatus Xenohaliotis californiensis (CXc) and its associated phage pCXc in black abalone of Baja California, Mexico.","authors":"Casandra Delgadillo-Anguiano, Fabiola Lafarga-De la Cruz, Julio Lorda, Carmen E Vargas-Peralta, Gabriela Montaño-Moctezuma, Beatriz Ibarra-Macías, Rodrigo Beas-Luna, Alicia Abadía-Cardoso","doi":"10.3354/dao03860","DOIUrl":"https://doi.org/10.3354/dao03860","url":null,"abstract":"Black abalone Haliotis cracherodii from California, USA, and Baja California, Mexico, have faced massive population declines for more than 30 yr. The main factors contributing to these declines have been overfishing, pollution, climate change, and lethal diseases, such as withering syndrome, caused by the intracellular bacterium Candidatus Xenohaliotis californiensis (CXc). In recent years, the presence of an associated bacteriophage, pCXc, infecting CXc was detected and reported in some abalone species from California and Baja California. In the present study, 199 black abalone fecal samples from 14 sites along the Baja California coast were analyzed for the presence of CXc and pCXc DNA. The overall prevalence of bacteria and phage-infected bacteria was 44 and 38%, respectively. We found significant differences in the relationship between the prevalence and the mean lengths of abalone throughout the study area. This result is probably due to differences in the size-frequency distribution between sampling zones. The only site where we found a relationship between prevalence and length was in Isla Todos Santos. We did not see a relationship between abalone density and the prevalence of the bacteria and the phage. Additionally, we found a positive but non-significant correlation in prevalence between CXc and pCXc. This study is the first to detect the presence of pCXc DNA in wild populations of black abalone of Baja California.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"163 ","pages":"25-38"},"PeriodicalIF":1.1,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Host-consumed resources increase pathogen load of endoparasites more than integument-infecting parasites. 宿主消耗的资源比被膜感染的寄生虫更能增加内寄生虫的病原体负荷。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-07-17 DOI: 10.3354/dao03861

Brin J Shayhorn, Chloe T Ramsay, Kristi Medina, Erin L Sauer, Jason R Rohr

{"title":"Host-consumed resources increase pathogen load of endoparasites more than integument-infecting parasites.","authors":"Brin J Shayhorn, Chloe T Ramsay, Kristi Medina, Erin L Sauer, Jason R Rohr","doi":"10.3354/dao03861","DOIUrl":"https://doi.org/10.3354/dao03861","url":null,"abstract":"Pathogens use host resources for replication. Consequently, pathogen traits, such as where they infect a host, might allow pathogens to capitalize on host-consumed nutrients before the host. For instance, parasites with short generation times in the host gut or blood might benefit more from host-consumed resources than the host, whereas parasites in or on the host integument (e.g. skin, cuticle, exoskeleton), such as ectoparasites, might benefit less from host-consumed resources than the host. Thus, it is unclear whether increased food consumption by hosts should reduce or amplify pathogen levels. We conducted experiments on Cuban treefrogs Osteopilus septentrionalis to test how food availability affects infection levels of ranavirus and the fungal pathogen Batrachochytrium dendrobatidis (Bd), which are both associated with mass die-offs of amphibians. Given that ranavirus is an endoparasite with a much shorter generation time than the skin-infecting Bd, we postulated that ranavirus might be able to capitalize on host-consumed resources more quickly than Bd. Hence, we hypothesized that increased food availability to hosts might reduce Bd infections more than ranavirus infections. As predicted, augmenting food access decreased Bd infection intensity but increased ranavirus infection intensity. Future work should assess whether pathogen traits, such as generation time and where they infect hosts, generally affect whether food resources more positively benefit hosts or pathogens.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"163 ","pages":"39-47"},"PeriodicalIF":1.1,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low abnormality rate shows the tentacular armature to be a reliable morphological character in trypanorhynch cestode taxonomy. 低异常率表明触手枢椎是一种可靠的锥体分类特征。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-07-17 DOI: 10.3354/dao03857

Harry W Palm, Eva Jakob, Xaver Neitemeier-Duventester, Mohammad Haseli

{"title":"Low abnormality rate shows the tentacular armature to be a reliable morphological character in trypanorhynch cestode taxonomy.","authors":"Harry W Palm, Eva Jakob, Xaver Neitemeier-Duventester, Mohammad Haseli","doi":"10.3354/dao03857","DOIUrl":"https://doi.org/10.3354/dao03857","url":null,"abstract":"A total of 4193 specimens with everted tentacles of the trypanorhynch cestode Mixonybelinia lepturi obtained from Gempylus serpens and Trichiurus lepturus were examined in order to identify abnormalities in hook shape and armature pattern. The abnormality rate of the tentacular hooks and armature was 0.09%, ranging from changed hook direction and slight changes of single hook shapes to completely altered hooks and armature patterns. In a single case, the armature pattern could not be assigned to any existing trypanorhynch family. The observed malformations were classified in 5 categories and 9 types, a categorization also to be used as a standard for other trypanorhynchs. The low abnormality rate demonstrates high reliability of tentacular hooks and armature patterns as taxonomic characters in trypanorhynch systematics, confirming that trypanorhynch larvae have identical tentacular armatures compared with their adults. Considering the low rate of abnormality, the role of environmental factors in causing the unsymmetrical changes on originally symmetrical tentacles is probably weak. Therefore, a genetic origin seems to be more probable. Such phenotypic armature variations may cause transfer of worms to new attachment sites within the same host or into a new host species, where new tentacular armatures with increased fitness are eventually formed by natural selection under the model of micro-allopatric speciation. The finding of an abnormal tentacle that unites hollow and solid hooks together with completely altered hook shapes and armature patterns is good evidence in demonstrating the ancient origin of different hook shapes and the evolutionary changes of armature patterns.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"163 ","pages":"49-62"},"PeriodicalIF":1.1,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erysipelothrix in Cook Inlet, Alaska, USA: an emerging bacterial pathogen of the endangered Cook Inlet beluga whale. 美国阿拉斯加州库克湾的丹毒：濒危的库克湾白鲸的一种新出现的细菌病原体。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-07-03 DOI: 10.3354/dao03859

Natalie Rouse, Kathy Burek Huntington, Caroline E C Goertz, Natalie Hunter, Sreejith Radhakrishnan, Taya Forde

引用次数: 0

Poorly differentiated neuroendocrine tumor and vertebral anomalies in a stranded Franciscana dolphin Pontoporia blainvillei. 一只搁浅的Franciscana dolphin Pontoporia blainvillei的低分化神经内分泌肿瘤和椎体异常。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-07-03 DOI: 10.3354/dao03858

Angélica M Sánchez-Sarmiento, Natalia C C A Fernandes, Raquel B Ferioli, Rodrigo A Ressio, Rode P Gomes, Gabrielle F P S Gagliotti, Hugo Gallo-Neto, Carla B Barbosa

{"title":"Poorly differentiated neuroendocrine tumor and vertebral anomalies in a stranded Franciscana dolphin Pontoporia blainvillei.","authors":"Angélica M Sánchez-Sarmiento, Natalia C C A Fernandes, Raquel B Ferioli, Rodrigo A Ressio, Rode P Gomes, Gabrielle F P S Gagliotti, Hugo Gallo-Neto, Carla B Barbosa","doi":"10.3354/dao03858","DOIUrl":"10.3354/dao03858","url":null,"abstract":"The Franciscana dolphin Pontoporia blainvillei is one of the most endangered cetaceans in the South Atlantic Ocean, primarily threatened due to bycatch. Knowledge regarding the natural causes of mortality and morbidity in this species is still limited. An adult female P. blainvillei that died as a result of bycatch was found stranded on the north coast of São Paulo, Brazil. At necropsy, a multi-cavitary tumor (~10.8 × 10.1 cm, 431 g) was found on the left adrenal gland, and on cut section, the tumor was hemorrhagic and necrotic. On histopathology, the tumor presented anaplastic characteristics including moderate anisocytosis and anisokaryosis, homogeneous and finely stippled chromatin, and nucleoli sometimes evident. Occasional binucleations and atypical giant cells were observed. The tumor was immunoreactive for chromogranin A and negative/not immunoreactive for Factor VIII, CD31, pan-cytokeratin AE1/AE3, vimentin, CD56, and synaptophysin, suggesting a poorly differentiated neuroendocrine tumor (NET). A moderate deviation of the lumbar spine (lordosis), lumbar ankylosing spondylosis, and thoracolumbar and caudal spine discopathy were confirmed via post-mortem radiographs. The vertebral anomalies and NET contribute to the knowledge of natural diseases of this endangered dolphin species.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"163 ","pages":"17-24"},"PeriodicalIF":1.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144552498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nutritional steatitis (yellow fat disease) in cultured silver catfish Rhamdia quelen associated with rancid feed. 与腐臭饲料有关的养殖银鲶营养性脂肪炎（黄脂肪病）。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-06-19 DOI: 10.3354/dao03856

Germán Alberto Coscelli, Cecilia Casabonne, Francisco Gauna, Marcia Samardich, Esteban Morón-Alcain, Fabricio Andrés Vigliano

{"title":"Nutritional steatitis (yellow fat disease) in cultured silver catfish Rhamdia quelen associated with rancid feed.","authors":"Germán Alberto Coscelli, Cecilia Casabonne, Francisco Gauna, Marcia Samardich, Esteban Morón-Alcain, Fabricio Andrés Vigliano","doi":"10.3354/dao03856","DOIUrl":"https://doi.org/10.3354/dao03856","url":null,"abstract":"Nutritional steatitis (yellow fat disease) caused by vitamin E (vitE) deficiency is typically associated with diets high in unsaturated fatty acids or/and low levels of vitE. This work describes, for the first time, an outbreak of nutritional steatitis in cultured silver catfish Rhamdia quelen in Argentina. Necropsy, histopathology, bacteriology and molecular studies of the affected fish were performed. In addition, peroxide level and vitE concentration of the fish feed were measured. Affected specimens had firm, yellowish-brown dermo-hypodermal nodules located in the adipose fin and dorsal region of the body. Histologically, lesions consisted of fat necrosis and multifocal granulomatous lobular steatitis, primarily affecting the subcutaneous and intermuscular adipose tissue, and occasionally, the coelomic fat. Feed analyses revealed a high peroxide value (41.2 mEq kg-1), indicative of rancid feed, and a low concentration of vitE (2.7 IU kg-1). In this case, fish had been fed rancid food with an inadequate value of vitE, leading to the development of nutritional steatitis caused by vitE deficiency.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"162 ","pages":"135-141"},"PeriodicalIF":1.1,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144324708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bonamia exitiosa: the cause of bonamiasis in native oysters Ostrea angasi in Australia in 2015. 2015年澳大利亚本地牡蛎Ostrea angasi的博纳米亚病。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-06-05 DOI: 10.3354/dao03853

Tracey L Bradley, Peter G Mohr, John D Humphrey, Nicholas J G Moody, David Cummins, Joanne Slater, Mark St J Crane

{"title":"Bonamia exitiosa: the cause of bonamiasis in native oysters Ostrea angasi in Australia in 2015.","authors":"Tracey L Bradley, Peter G Mohr, John D Humphrey, Nicholas J G Moody, David Cummins, Joanne Slater, Mark St J Crane","doi":"10.3354/dao03853","DOIUrl":"https://doi.org/10.3354/dao03853","url":null,"abstract":"Bonamiasis, caused by haplosporidian parasites Bonamia spp., is an infectious disease prevalent in 'flat' oysters internationally. Bonamia was first detected in Australian native oysters Ostrea angasi in Victorian waters in the early 1990s and caused mass mortalities in this pilot industry. The species identity of Bonamia at that time was unclear and no attempts were made to unequivocally resolve it. Interest in O. angasi culture was renewed in 2010 alongside a small-scale bonamiasis surveillance programme, given previous experience with the parasite. Basic data on culture methods, epidemiology and pathology are presented from 2011 until the epizootic that destroyed most of the stock at the major aquaculture site in 2015. At that time, a comprehensive phylogenetic analysis of the relationship between the cause of this epizootic and other Bonamia spp. internationally demonstrated >98% homology to B. exitiosa. Moreover, the report on Perkinsus olseni is the first in O. angasi. The presumed incidental finding of the more recently identified P. beihaiensis is the first for any mollusc species in Australia.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"162 ","pages":"99-113"},"PeriodicalIF":1.1,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144224608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gastric perforation associated with feather ingestion in American shad Alosa sapidissima housed in a multispecies habitat. 在多物种栖息地中饲养的美洲沙鱼的胃穿孔与羽毛摄食有关。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-06-05 DOI: 10.3354/dao03854

Benjamin Balducchi, Stéphane Lair, Charlotte E Day

{"title":"Gastric perforation associated with feather ingestion in American shad Alosa sapidissima housed in a multispecies habitat.","authors":"Benjamin Balducchi, Stéphane Lair, Charlotte E Day","doi":"10.3354/dao03854","DOIUrl":"https://doi.org/10.3354/dao03854","url":null,"abstract":"Pathological conditions associated with feather ingestion have rarely been reported in any species and not previously in fish. From 2013 to 2024, 87 American shad Alosa sapidissima collected from the wild for display purposes were housed in a multispecies habitat within a zoological facility, alongside various fish, invertebrate and bird species from the St. Lawrence Estuary (Quebec, Canada) ecozone. Since 2013, 81 of the 87 shad either died or were euthanized due to health issues, and macroscopic examinations were performed on 36 of these. Bird feathers were present within the gastric lumen in 12 of the 36 fish and were associated with penetrating perforations of the gastric wall with gross evidence of peritonitis in 11 of the 12 cases. Histopathologic examinations were performed in 7 of the affected fish and in 6 revealed the presence of transmural, focally extensive granulomatous infiltration of the gastric wall, centered on foreign bodies morphologically characteristic of feather shafts and barbs. Significant comorbidities included trauma (n = 18) and systemic Ichthyophonus infection associated with granulomatous reaction, which was considered a potential contributory cause of morbidity and mortality in at least 2 fish, including 1 with gastric feather perforation. Incidental encysted anisakid nematodes within the coelomic cavity, intestines and liver were also observed (n = 3). Eight of the affected fish were underconditioned, suggestive of chronic morbidity. This case series indicates that American shad are prone to ingesting bird feathers and highlights a previously unreported health issue associated with keeping this species in mixed exhibits with birds.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"162 ","pages":"115-122"},"PeriodicalIF":1.1,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144224610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Causes of death in Magellanic penguins Spheniscus magellanicus in southern Brazil. 巴西南部麦哲伦企鹅的死亡原因

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-06-05 DOI: 10.3354/dao03855

Jacqueline Raiter, Igor R Santos, Carolina B Brunner, Bianca S de Cecco, Derek B de Amorim, Marcele B Bandinelli, Welden Panziera, Saulo P Pavarini, David Driemeier, Luciana Sonne

{"title":"Causes of death in Magellanic penguins Spheniscus magellanicus in southern Brazil.","authors":"Jacqueline Raiter, Igor R Santos, Carolina B Brunner, Bianca S de Cecco, Derek B de Amorim, Marcele B Bandinelli, Welden Panziera, Saulo P Pavarini, David Driemeier, Luciana Sonne","doi":"10.3354/dao03855","DOIUrl":"https://doi.org/10.3354/dao03855","url":null,"abstract":"Magellanic penguins Spheniscus magellanicus are seasonal migratory seabirds. During the migratory period, these penguins are observed mainly in the seas of Argentina, Uruguay, and Brazil. Studies on mortality events in the species are limited, particularly those comparing free-ranging and captive penguins. This study describes the causes of death and pathological findings in Magellanic penguins using necropsy records from a retrospective study (2011-2021). Records from 164 penguins were analyzed, comprising 95 in captivity, 68 free-ranging, and 1 of undetermined origin. Non-infectious diseases (n = 104) were predominant in free-ranging penguins and included starvation (n = 49), suspected drowning (n = 27), hypothermia secondary to oil pollution (n = 25), trauma (n = 2), and intestinal obstruction (n = 1). Infectious/inflammatory diseases (n = 23) were most frequent among captive populations, including cases of malaria (n = 9), aspergillosis (n = 7), other mycotic infections (n = 3), bacterial infection (n = 2), protozoal meningoencephalitis (n = 1), and granulomatous air sacculitis of unknown origin (n = 1). Juvenile penguins constituted most cases in both non-infectious and infectious categories. There were 37 cases of undetermined diagnoses. Gastrointestinal parasitosis, cutaneous lesions, and pulmonary edema were the main secondary pathologic findings. These results enhance our understanding of the diseases affecting the Magellanic penguins and provide valuable insights for the conservation and maintenance of free-ranging and captive penguins.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"162 ","pages":"123-133"},"PeriodicalIF":1.1,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144224609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Histological progression and bacterial load dynamics of Renibacterium salmoninarum in Chinook salmon Oncorhynchus tshawytscha. 奇努克鲑鱼体内沙门氏菌的组织学进展和细菌负荷动态。

IF 1.1 4区农林科学

Diseases of aquatic organisms Pub Date : 2025-05-22 DOI: 10.3354/dao03852

Riley E Dils, Tawni B R Firestone, Paula A Schaffer, Dana L Winkelman, Eric R Fetherman

{"title":"Histological progression and bacterial load dynamics of Renibacterium salmoninarum in Chinook salmon Oncorhynchus tshawytscha.","authors":"Riley E Dils, Tawni B R Firestone, Paula A Schaffer, Dana L Winkelman, Eric R Fetherman","doi":"10.3354/dao03852","DOIUrl":"https://doi.org/10.3354/dao03852","url":null,"abstract":"Renibacterium salmoninarum, the cause of bacterial kidney disease (BKD), severely impacts salmonid populations. Much of our understanding of the BKD pathology in salmonids comes from evaluating fatal infections in wild populations or spawning Pacific Northwest salmonids. Our study investigated the histological progression and bacterial load dynamics of R. salmoninarum infection in Chinook salmon following intraperitoneal injection to enhance understanding of the disease's dynamics. Seventy presmolt salmon were injected with the ATCC-33209 isolate of R. salmoninarum and monitored over 10 wk. Histological signs of disease were observed in spleen and liver tissues at 1 wk post-injection and in kidney tissues at 4 wk post-injection, with signs of disease increasing over time. Additionally, histopathological analysis revealed splenic and hepatic capsulitis (coelomitis), individual hepatocyte necrosis, progressive granulomatous hepatitis, splenitis, and nephritis with necrosis. Gram staining confirmed the presence of Gram-positive bacteria within macrophages and extracellularly in infected tissues. Quantitative PCR revealed significant increases in bacterial loads in both kidney and liver tissues over the study period, with higher bacterial loads observed in the kidney tissue. Bacterial load was strongly correlated with disease stage, with peak bacterial burdens coinciding with the most severe histological changes. Our study provides a comprehensive account of R. salmoninarum infection and disease progression in Chinook salmon after intraperitoneal injection.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"162 ","pages":"85-97"},"PeriodicalIF":1.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0