Veterinary Pathology最新文献

{"title":"Massive branchial henneguyosis of catfish: A distinct, myxozoan-induced gill disease caused by severe interlamellar <i>Henneguya exilis</i> infection in catfish aquaculture.","authors":"Justin M Stilwell, Matt J Griffin, John H Leary, Lester H Khoo, Alvin C Camus","doi":"10.1177/03009858241259181","DOIUrl":"10.1177/03009858241259181","url":null,"abstract":"<p><p>Proliferative gill disease (PGD), caused by the myxozoan <i>Henneguya ictaluri</i>, has been the most notorious parasitic gill disease in the US catfish aquaculture industry. In 2019, an unusual gill disease caused by massive burdens of another myxozoan, <i>Henneguya exilis</i>, was described in channel (<i>Ictalurus punctatus</i>) × blue (<i>Ictalurus furcatus</i>) hybrid catfish. Targeted metagenomic sequencing and <i>in situ</i> hybridization (ISH) were used to differentiate these conditions by comparing myxozoan communities involved in lesion development and disease pathogenesis between massive <i>H. exilis</i> infections and PGD cases. Thirty ethanol-fixed gill holobranchs from 7 cases of massive <i>H. exilis</i> infection in hybrid catfish were subjected to targeted amplicon sequencing of the <i>18S rRNA</i> gene and compared to a targeted metagenomic data set previously generated from clinical PGD case submissions. Furthermore, serial sections of 14 formalin-fixed gill holobranchs (2 per case) were analyzed by RNAscope duplex chromogenic ISH assays targeting 8 different myxozoan species. Targeted metagenomic and ISH data were concordant, indicating myxozoan community compositions significantly differ between PGD and massive branchial henneguyosis. Although PGD cases often consist of mixed species infections, massive branchial henneguyosis consisted of nearly pure <i>H. exilis</i> infections. Still, <i>H. ictaluri</i> was identified by ISH in association with infrequent PGD lesions, suggesting coinfections occur, and some cases of massive branchial henneguyosis may contain concurrent PGD lesions contributing to morbidity. These findings establish a case definition for a putative emerging, myxozoan-induced gill disease of farm-raised catfish with a proposed condition name of massive branchial henneguyosis of catfish (MBHC).</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"965-972"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141306958","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":"Effects of fixation and demineralization on histomorphology and DNA amplification of canine bone marrow.","authors":"Gabriella M L Diamantino, Janet Beeler-Marfisi, Robert A Foster, William Sears, Alice Defarges, William Vernau, Dorothee Bienzle","doi":"10.1177/03009858241257920","DOIUrl":"10.1177/03009858241257920","url":null,"abstract":"<p><p>Fixation and demineralization protocols for bone marrow (BM) across diagnostic laboratories are not standardized. How different protocols affect histomorphology and DNA amplification is incompletely understood. In this study, 2 fixatives and 3 demineralization methods were tested on canine BM samples. Twenty replicate sternal samples obtained within 24 hours of death were fixed overnight in either acetic acid-zinc-formalin (AZF) or 10% neutral-buffered formalin (NBF) and demineralized with formic acid for 12 hours. Another 53 samples were fixed in AZF and demineralized with hydrochloric acid for 1-hour, formic acid for 12 hours, or ethylenediamine tetraacetic acid (EDTA) for 24 hours. Histologic sections were scored by 4 raters as of insufficient, marginal, good, or excellent quality. In addition, DNA samples extracted from sections treated with the different fixation and demineralization methods were amplified with 3 sets of primers to conserved regions of <i>T cell receptor gamma</i> and <i>immunoglobulin heavy chain</i> genes. Amplification efficiency was graded based on review of capillary electrophoretograms. There was no significant difference in the histomorphology scores of sections fixed in AZF or NBF. However, EDTA-based demineralization yielded higher histomorphology scores than demineralization with hydrochloric or formic acid, whereas formic acid resulted in higher scores than hydrochloric acid. Demineralization with EDTA yielded DNA amplification in 29 of 36 (81%) samples, whereas demineralization with either acid yielded amplification in only 2 of 72 (3%) samples. Although slightly more time-consuming and labor-intensive, tissue demineralization with EDTA results in superior morphology and is critical for polymerase chain reaction (PCR) amplification with the DNA extraction method described in this article.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"943-951"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11538782/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141263000","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":"Letters or not, here we come! A communal perspective on credentials needed for a productive career in veterinary pathology.","authors":"Ingrid D Pardo, Ingeborg M Langohr, Phaedra Cole, Sue E Knoblaugh, Richard Luong, Keith Mansfield, Andres Mejia, Emily Meseck, Andrew D Miller, Kelley Penraat, Angela Pillatzki, Brad Bolon","doi":"10.1177/03009858241269926","DOIUrl":"10.1177/03009858241269926","url":null,"abstract":"<p><p>Veterinary pathology credentials serve as a concise means attesting to educational attainments and experiences indicating a readiness for professional practice. Given the cost, time, and stress associated with obtaining different qualifications, pathologists must consider what credentials enhance their readiness. In this commentary, the authors describe how their various degrees and certifications have facilitated their individual and organizational success. The minimum credentials for proficient veterinary pathology practice are a veterinary medical degree (DVM or equivalent) and advanced pathology training (residency and/or on-the-job \"apprenticeship\") ideally culminating in board certification in pathology (American College of Veterinary Pathologists [ACVP] diplomate status or equivalent). Graduate degrees (MS, PhD, MPH, etc) and/or other qualifications in allied biomedical fields (eg, board certification in internal medicine, laboratory animal medicine, poultry medicine, preventive medicine, or toxicology) may improve employability by affirming specialty knowledge in another complementary discipline. The authors note that pathology positions may be obtained without a long list of degrees or certifications, and that more credentials may provide occupational flexibility for some employers. However, a good work ethic, experience in the field, ability to adapt to changes, job satisfaction, good attitude, and demonstrated productivity are also important, and indeed, they are often the paramount criteria for career success as a veterinary pathologist.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"870-873"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142005363","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":"<i>Helicosporidium</i> sp. infection in a California kingsnake (<i>Lampropeltis californiae</i>): Spillover of a pathogen of invertebrates to a vertebrate host.","authors":"Javier Asin, April L Childress, Eva Dervas, Michael M Garner, Francisco A Uzal, James F X Wellehan, Eileen E Henderson, Anibal G Armien","doi":"10.1177/03009858241259179","DOIUrl":"10.1177/03009858241259179","url":null,"abstract":"<p><p><i>Helicosporidium</i> is a genus of nonphotosynthetic, green algae in the family <i>Chlorellaceae</i>, closely related to <i>Prototheca</i>. It is a known pathogen of invertebrates, and its occurrence in vertebrates has not been documented. A captive, 10-month-old, male, albino California kingsnake (<i>Lampropeltis californiae</i>) was submitted for necropsy. Gross examination revealed hemorrhagic laryngitis and a red mottled liver. Histologically, intravascular, intramonocytic/macrophagic and extracellular, eukaryotic organisms were observed in all tissues. These organisms stained positive with Grocott-Gomori methenamine silver and periodic acid-Schiff and were variably acid-fast and gram-positive. Ultrastructural analysis revealed approximately 4 µm vegetative multiplication forms and cysts with 3 parallel ovoid cells and a helically coiled filamentous cell. A polymerase chain reaction with primers targeting <i>Prototheca</i>, amplicon sequencing, and Bayesian phylogenetic analysis confirmed it clustered within <i>Helicosporidium</i> sp. with 100% posterior probability. The genus <i>Helicosporidium</i> was found to nest within the genus <i>Prototheca</i>, forming a clade with <i>Prototheca wickerhamii</i> with 80% posterior probability.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"978-982"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11538780/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141331903","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":"Histopathologic evaluation system of African swine fever in wild boar infected with high (Arm07) and low virulence (Lv17/WB/Riel) isolates.","authors":"Néstor Porras, José M Sánchez-Vizcaíno, José Á Barasona, Alberto Gómez-Buendía, Estefanía Cadenas-Fernández, Antonio Rodríguez-Bertos","doi":"10.1177/03009858241266944","DOIUrl":"10.1177/03009858241266944","url":null,"abstract":"<p><p>To understand the clinicopathological forms of African swine fever (ASF) in wild boar, it is crucial to possess a basic knowledge of the biological characteristics of the currently circulating ASF virus isolates. The aim of this work is to establish an accurate and comprehensive histopathologic grading system to standardize the assessment of the ASF lesions in wild boar. The study evaluated the differences between animals infected with a high virulence genotype II isolate (Arm07) (HVI) through intramuscular (IM) (n = 6) and contact-infected (n = 12) routes, alongside those orally infected with a low virulence isolate (Lv17/WB/Riel) (LVI) (n = 6). The assessment included clinical (CS), macroscopic (MS), and histopathologic (HS) scores, as well as viral loads in blood and tissues by real-time quantitative polymerase chain reaction (qPCR). Tissues examined included skin, lymph nodes, bone marrow, palatine tonsil, lungs, spleen, liver, kidneys, thymus, heart, adrenal glands, pancreas, urinary bladder, brain, and gastrointestinal and reproductive tracts. The HVI group exhibited a 100% mortality rate with elevated CS, MS, and HS values. Animals infected by contact (CS = 12; MS = 58.5; HS = 112) and those intramuscularly infected (CS = 14.8; MS = 47; HS = 104) demonstrated similar values, indicating that the route of infection does not decisively influence the severity of clinical and pathological signs. The LVI group showed a 0% mortality rate, an inconspicuous clinical form, minimal lesions (CS = 0; MS = 12; HS = 29), and a lower viral load. Histopathologic evaluation has proven valuable in advancing our comprehension of ASF pathogenesis in wild boar and paves the groundwork for further research investigating protective mechanisms in vaccinated animals.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"928-942"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141793625","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":"Comparative and experimental pathology of passaged Newcastle disease virus isolates in ducks.","authors":"Sohta Hishikawa, Yuji Sunden, Aoi Imamura, Chiharu Hidaka, Hiroshi Ito, Toshihiro Ito, Takehito Morita","doi":"10.1177/03009858241286817","DOIUrl":"https://doi.org/10.1177/03009858241286817","url":null,"abstract":"<p><p>Although waterfowl are less susceptible to Newcastle disease (ND) virus (NDV) infection compared with chickens and turkeys, lethal ND in waterfowl has been sporadically reported. Factors underlying the high pathogenicity of certain NDV strains in waterfowl remain unclear. In ducks, the NDV 9a5b isolate shows low pathogenicity while the d5a20b isolate shows high pathogenicity. This study aimed to identify the definitive lesions that led to the lethal virulence of d5a20b by comparing the histopathology of 9a5b- or d5a20b-inoculated ducks in order to elucidate lesions related to the enhanced pathogenicity of certain NDV strains in ducks. Herein, 7-day-old ducks were intranasally inoculated with either 9a5b or d5a20b NDV strains. The neurological signs were more severe in the d5a20b-inoculated group than in the 9a5b-inoculated group. Ducks in the d5a20b-inoculated group exhibited more severe lymphoid depletion in immune organs than those in the 9a5b-inoculated group, which may have caused an immunosuppressive state in the d5a20b-inoculated ducks. Ducks in the d5a20b-inoculated group had more severe nonsuppurative encephalitis with increased NDV nucleoprotein than those in the 9a5b-inoculated group. Additionally, pancreatic necrosis, with intralesional NDV nucleoprotein, was more severe in the d5a20b-inoculated group than in the 9a5b-inoculated group. Our results showed that the immune organs, brain, and pancreas were significant targets of the NDV d5a20b infection in ducks.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"3009858241286817"},"PeriodicalIF":2.3,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142475926","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":"Artificial intelligence can be trained to predict <i>c-KIT</i>-11 mutational status of canine mast cell tumors from hematoxylin and eosin-stained histological slides.","authors":"Chloé Puget, Jonathan Ganz, Julian Ostermaier, Thomas Conrad, Eda Parlak, Christof A Bertram, Matti Kiupel, Katharina Breininger, Marc Aubreville, Robert Klopfleisch","doi":"10.1177/03009858241286806","DOIUrl":"https://doi.org/10.1177/03009858241286806","url":null,"abstract":"<p><p>Numerous prognostic factors are currently assessed histologically and immunohistochemically in canine mast cell tumors (MCTs) to evaluate clinical behavior. In addition, polymerase chain reaction (PCR) is often performed to detect internal tandem duplication (ITD) mutations in exon 11 of the <i>c-KIT</i> gene (<i>c-KIT</i>-11-ITD) to predict the therapeutic response to tyrosine kinase inhibitors. This project aimed at training deep learning models (DLMs) to identify MCTs with <i>c-KIT</i>-11-ITD solely based on morphology. Hematoxylin and eosin (HE) stained slides of 368 cutaneous, subcutaneous, and mucocutaneous MCTs (195 with ITD and 173 without) were stained consecutively in 2 different laboratories and scanned with 3 different slide scanners. This resulted in 6 data sets (stain-scanner variations representing diagnostic institutions) of whole-slide images. DLMs were trained with single and mixed data sets and their performances were assessed under stain-scanner variations (domain shifts). The DLM correctly classified HE slides according to their <i>c-KIT</i>-11-ITD status in up to 87% of cases with a 0.90 sensitivity and a 0.83 specificity. A relevant performance drop could be observed when the stain-scanner combination of training and test data set differed. Multi-institutional data sets improved the average accuracy but did not reach the maximum accuracy of algorithms trained and tested on the same stain-scanner variant (ie, intra-institutional). In summary, DLM-based morphological examination can predict <i>c-KIT</i>-11-ITD with high accuracy in canine MCTs in HE slides. However, staining protocol and scanner type influence accuracy. Larger data sets of scans from different laboratories and scanners may lead to more robust DLMs to identify c-<i>KIT</i> mutations in HE slides.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"3009858241286806"},"PeriodicalIF":2.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142475924","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":"Artificial intelligence-based quantification of lymphocytes in feline small intestinal biopsies.","authors":"Judit M Wulcan, Paula R Giaretta, Sai Fingerhood, Simone de Brot, Esther E V Crouch, Tatiana Wolf, Maria Isabel Casanova, Pedro R Ruivo, Pompei Bolfa, Nicolás Streitenberger, Christof A Bertram, Taryn A Donovan, Michael Kevin Keel, Peter F Moore, Stefan M Keller","doi":"10.1177/03009858241286828","DOIUrl":"https://doi.org/10.1177/03009858241286828","url":null,"abstract":"<p><p>Feline chronic enteropathy is a poorly defined condition of older cats that encompasses chronic enteritis to low-grade intestinal lymphoma. The histological evaluation of lymphocyte numbers and distribution in small intestinal biopsies is crucial for classification and grading. However, conventional histological methods for lymphocyte quantification have low interobserver agreement, resulting in low diagnostic reliability. This study aimed to develop and validate an artificial intelligence (AI) model to detect intraepithelial and lamina propria lymphocytes in hematoxylin and eosin-stained small intestinal biopsies from cats. The median sensitivity, positive predictive value, and F1 score of the AI model compared with the majority opinion of 11 veterinary anatomic pathologists, were 100% (interquartile range [IQR] 67%-100%), 57% (IQR 38%-83%), and 67% (IQR 43%-80%) for intraepithelial lymphocytes, and 89% (IQR 71%-100%), 67% (IQR 50%-82%), and 70% (IQR 43%-80%) for lamina propria lymphocytes, respectively. Errors included false negatives in whole-slide images with faded stain and false positives in misidentifying enterocyte nuclei. Semiquantitative grading at the whole-slide level showed low interobserver agreement among pathologists, underscoring the need for a reproducible quantitative approach. While semiquantitative grade and AI-derived lymphocyte counts correlated positively, the AI-derived lymphocyte counts overlapped between different grades. Our AI model, when supervised by a pathologist, offers a reproducible, objective, and quantitative assessment of feline intestinal lymphocytes at the whole-slide level, and has the potential to enhance diagnostic accuracy and consistency for feline chronic enteropathy.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"3009858241286828"},"PeriodicalIF":2.3,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142475925","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":"A novel missense variant in the <i>RELN</i> gene in sheep with lissencephaly and cerebellar hypoplasia.","authors":"Leah K Manning, Emily Winkenwerder, Louise Baskind, Katie L M Eager, Cali E Willet, Ben Porebski, Brendon A O'Rourke, Imke Tammen, Marina Gimeno, Pedro Pinczowski","doi":"10.1177/03009858241283501","DOIUrl":"https://doi.org/10.1177/03009858241283501","url":null,"abstract":"<p><p>Lissencephaly and cerebellar hypoplasia (LCH) represents a spectrum of congenital developmental malformations of the cerebral cortex and cerebellum, mostly occurring as inherited conditions caused by variants in an increasingly recognized number of genes. LCH has been identified in three Dorset-cross lambs with congenital neurological signs in Australia. Lambs were unable to walk and had reduced vision, and one lamb developed a hypermetric gait and intention tremors. Grossly, the lambs had diffuse pachygyria with reduction in white matter, mild bilateral ventriculomegaly of the lateral ventricles, and a markedly hypoplastic cerebellum. Histologically, there was disorganization of neurons within the cerebral cortex and hippocampus. The cerebellar vermis had disorganized, thin, and hypocellular gray matter with frequent ectopic Purkinje cells, while identifiable folia were largely absent within the hemispheres. Luxol fast blue stain and glial fibrillary acidic protein, neuronal nuclear protein, synaptophysin, and neuron-specific enolase immunohistochemistry confirmed the thickened, disorganized cerebral cortical gray matter and reduced white matter. Within the cerebellum, immunohistochemistry demonstrated marked dysplasia. Whole-genome sequencing analysis and prediction of variant effects identified a missense variant of interest in the candidate gene <i>reelin</i> (<i>RELN</i>; NC_040255.1:g.50288685C>T; NM_001306121.1:c.7088G>A; NP_001293050.1:p.(R2363H)) with a deleterious Sorting Intolerant from Tolerant (SIFT) score. Sanger sequencing identified that the variant segregated with LCH disease in the 3 affected individuals, their sire, and 6 unaffected flock members. The NP_001293050.1: p.(R2363H) substitution is predicted to decrease the stability of the protein (ΔΔG = -1.55 kcal/mol). Pathological and genetic findings are consistent with previously described phenotypes of <i>RELN</i> variants in Churra sheep, dogs, and humans.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"3009858241283501"},"PeriodicalIF":2.3,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142475923","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":"Encephalomyelitis and serositis caused by <i>Chlamydia pecorum</i> in buffalo calves from Brazil.","authors":"Larissa L de Souza, Saulo P Pavarini, Marcele B Bandinelli, Nicole Borel, Rayane C Pupin, Carlos A N Ramos, Ricardo A A Lemos, Danilo C Gomes","doi":"10.1177/03009858241288116","DOIUrl":"https://doi.org/10.1177/03009858241288116","url":null,"abstract":"<p><p><i>Chlamydia pecorum</i> causes subclinical infections in cattle, but sporadic, bovine encephalomyelitis cases have been reported in calves and documented in two instances in European buffalo. An outbreak of <i>Chlamydia pecorum</i>-induced encephalomyelitis and serositis occurred in 3-month-old buffalo calves from Brazil. Initially presenting with pelvic limb incoordination, the calves progressed to lateral recumbency, depression, and death. Necropsies of two calves revealed encephalomyelomalacia, fibrin deposition on the external surface of the pericardium (case 1) and pleural and pericardial fibrosis (case 2). Microscopically, a multifocal to coalescing, necrotizing, neutrophilic and lymphocytic meningoencephalomyelitis with fibrinoid vasculitis and thrombosis was present. Anti-<i>Chlamydia</i> antibody labeling was demonstrated by immunohistochemistry. Bacteriological examination yielded no pathogenic bacteria in the brain or lungs. <i>Chlamydia pecorum</i> was confirmed by PCR. This work describes the gross, histopathological, microbiological, and molecular findings in two cases from an outbreak of <i>Chlamydia pecorum</i>-induced disease in buffalo calves.</p>","PeriodicalId":23513,"journal":{"name":"Veterinary Pathology","volume":" ","pages":"3009858241288116"},"PeriodicalIF":2.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142401464","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}