Journal of Comparative Pathology最新文献

{"title":"Cardiac pathology associated with hypertension and chronic kidney disease in aged cats","authors":"Zara Flora ,&nbsp;Pak K. Tang ,&nbsp;Ken Smith ,&nbsp;Jonathan Elliott","doi":"10.1016/j.jcpa.2024.11.006","DOIUrl":"10.1016/j.jcpa.2024.11.006","url":null,"abstract":"<div><div>Hypertension is a common condition in older cats, often secondary to chronic kidney disease (CKD). Although the heart is one of the organs damaged by hypertension, the pathology of the feline hypertensive (HT) heart has been poorly studied. The aim of this retrospective study was to describe the gross and microscopic pathology of hearts obtained from cats at post-mortem examination and to compare cats diagnosed with hypertension with cats of similar age and kidney function for which antihypertensive treatment was not deemed clinically necessary. Hearts from 32 cats were examined‒18 from HT and 14 from normotensive (NT) cats. The prevalence of CKD was 72.2% vs. 78.6% in the HT and NT groups, respectively. The time-averaged blood pressure over the longitudinal follow-up from diagnosis was significantly higher in the HT group compared with the NT group (153.4 ± 20.8 vs. 133.9 ± 19.3 mmHg; <em>P</em> = 0.0106), respectively. HT cats, when compared with NT cats, had a thicker left ventricular free wall (7.67 [5.45–9.29] vs. 5.07 [4.72–7.16] mm; <em>P</em> = 0.001) and interventricular septum (6.92 [6.26–7.56] vs. 4.96 [4.15–6.46] mm; <em>P</em> = 0.008) and higher ventricular weight as a percentage of body weight (0.34 [0.29–0.36] vs. 0.28 [0.21–0.31]%; <em>P</em> = 0.02), respectively. Myocardial fibrosis was present in 72% of cases with no significant difference in the prevalence (<em>P</em> = 0.45) or score (<em>P</em> = 0.81) between the HT (1 [0.75–2]; 77.8% scoring one or above) and NT cats (1 [0–2]; 64.3% scoring one or above). Similarly, the population prevalence of myocyte hypertrophy, myofibre disarray and microvascular change was 71.9%, 50% and 43.7%, respectively, and did not differ significantly between groups. These results suggest that age-related cardiac pathology, exacerbated by azotaemic CKD, in cats is very common. The role that hypertension plays in mediating these pathological changes is uncertain.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"216 ","pages":"Pages 40-49"},"PeriodicalIF":0.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142927307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Cellular pathophysiology of Leptospira interrogans infection in canine testicular tissue: role of the TLR4/NF-kB/JNK pathway","authors":"İsmail Bolat ,&nbsp;Merve Bolat ,&nbsp;Metin Kiliçlioğlu ,&nbsp;Serkan Yıldırım ,&nbsp;Yavuz S. Sağlam ,&nbsp;Selim Çomaklı ,&nbsp;Berrah Gözegir","doi":"10.1016/j.jcpa.2024.11.001","DOIUrl":"10.1016/j.jcpa.2024.11.001","url":null,"abstract":"<div><div>Leptospirosis is a prevalent zoonotic disease in dogs. Although it is known that leptospires are primarily harboured in kidney tissues of dogs, it has been reported that they also infect testicular tissue. <em>Leptospira interrogans</em> causes various lesions in canine testicular tissues; however, the pathogenesis has not been clearly explained. In this study, 20 canine testicular tissue samples infected with <em>L. interrogans</em> were investigated for evidence of oxidative DNA damage, inflammation, apoptosis and autophagy. Ten samples of canine testicular tissue that were negative for <em>L. interrogans</em> were used as a positive control group. All tissues were examined by histopathological, immunohistochemistry (IHC) and immunofluorescence (IF) methods. Histopathological examination revealed that testicular tissues infected with <em>L. interrogans</em> had inflammation and oedema, and degeneration and necrosis of spermatocytes. In cases of severe disease, enzyme-linked immunosorbent assay, reverse transcriptase polymer chain reaction and IHC and IF indicated significant increases in levels of TLR4, NF-kB, IL-1β, TNF-α, 8-OHdG, JNK1/3, caspase-8, caspase-3, LC3A and LC3B but lower levels in milder cases. These results indicate that <em>L. interrogans</em> stimulated the immune system through the TLR4/NF-kB/JNK pathway in dog testicular tissues, leading to inflammation and apoptosis. The infection also caused oxidative DNA damage and autophagy.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"216 ","pages":"Pages 10-19"},"PeriodicalIF":0.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142807358","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}

{"title":"Morphometry, cellular characterization and temporal evolution of granulomas induced by aluminium oxyhydroxide in sheep","authors":"Ana Rodríguez-Largo ,&nbsp;Álex Gómez ,&nbsp;Estela Pérez ,&nbsp;Ricardo de Miguel ,&nbsp;Irati Moncayola ,&nbsp;Lucia Biagini ,&nbsp;Giacomo Rossi ,&nbsp;Ignacio de Blas ,&nbsp;Antonio Fernández ,&nbsp;Marta Pérez ,&nbsp;Idoia Glaria ,&nbsp;Ramsés Reina ,&nbsp;Lluís Luján","doi":"10.1016/j.jcpa.2024.11.002","DOIUrl":"10.1016/j.jcpa.2024.11.002","url":null,"abstract":"<div><div>Persistent subcutaneous granulomas form at the injection site following administration of aluminium oxyhydroxide (AlOOH), a widely used vaccine adjuvant. Small ruminant lentiviruses (SRLVs) can infect macrophages within granulomas induced by commercial AlOOH-based vaccines in sheep. The entry of SRLVs into target cells involves the mannose receptor (<em>MR</em>), while catalytic polypeptide-like 3 protein containing Z1 domain (<em>A3Z1</em>) is considered a restriction factor for lentiviral replication. The objective of this study was to investigate the temporal evolution of AlOOH-induced post-vaccination granulomas in sheep experimentally infected with SRLVs. Twenty-four male lambs underwent two identical vaccination protocols and were challenged with SRLVs. Granulomas were detected in vaccinated groups only and progressively decreased in size. At post-mortem examination, 91.3% of the granulomas were recovered. Fistulas were present in granulomas following the second vaccination protocol. Central necrosis was present in 58.0% of granulomas and was associated with the vaccine used. Orthokeratotic keratin was seen within granulomas in 47.1% of the lambs. Considering all granulomas studied, significantly higher expression of <em>MR</em> was found compared with <em>A3Z1</em>. Differences in <em>MR</em> expression were related to the type of vaccine and the time since vaccination. <em>A3Z1</em> expression was upregulated in granulomas from the infected groups. Macrophage polarization may influence SRLV infection of granulomas. While SRLV infection does not influence the architecture of post-vaccination granulomas, it may modulate their immune microenvironment. Further studies are needed to elucidate the complex interactions between AlOOH-induced granulomas and SRLV infection in sheep.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"216 ","pages":"Pages 1-9"},"PeriodicalIF":0.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142794604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Anatomopathological characterization of hepatic lesions of feline infectious peritonitis in cats","authors":"Fernanda G. Cony,&nbsp;Vanessa C. Pereira,&nbsp;Mônica Slaviero,&nbsp;Rafael P. Lima,&nbsp;Lucas T. de Castro,&nbsp;José T.R. de Moraes,&nbsp;João M.G. Aliardi,&nbsp;David Driemeier,&nbsp;Luciana Sonne,&nbsp;Welden Panziera,&nbsp;Saulo P. Pavarini","doi":"10.1016/j.jcpa.2024.10.003","DOIUrl":"10.1016/j.jcpa.2024.10.003","url":null,"abstract":"<div><div>Feline infectious peritonitis (FIP) is one of the most important infectious diseases and a significant cause of death in cats. While the pathology of FIP has been well documented, there is little information on the hepatic lesions. The aim of this study was to characterize the macroscopic, microscopic and immunohistochemical patterns of the liver lesions in cats with FIP. A retrospective study was conducted on 131 cats with FIP, of which 59 had histological inflammatory lesions in the liver and were immunopositive for feline coronavirus. Four major gross patterns were defined: perihepatitis (21/59); nodular with perihepatitis (18/59); nodular multifocal (13/59); and diffuse (7/59). Four histological patterns were observed: (1) random pyogranulomas; (2) random multifocal to coalescent caseous necrosis surrounded by pyogranulomatous inflammatory infiltrate, fibrin and cellular debris; (3) perihepatitis; and (4) random multifocal to coalescent caseous necrosis surrounded by neutrophils, macrophages, lymphocytes and plasma cells. Most cats had more than one histological pattern. FIP virus antigen was detected in macrophages in the pyogranulomas and around the necrotic areas. The diagnosis of FIP remains challenging, especially in cats without effusion. The liver can be considered a suitable site for biopsy when feasible.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 59-65"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621426","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}

{"title":"Spontaneous ependymoma in a free-ranging juvenile black-horned capuchin (Sapajus nigritus)","authors":"Carolina Fontana ,&nbsp;Amália Ferronato ,&nbsp;Vinicius Dahm ,&nbsp;Marina M. Berón ,&nbsp;Stacy Wu ,&nbsp;Ronaldo J. Piccoli ,&nbsp;Anderson L. de Carvalho ,&nbsp;Aline de Marco Viott","doi":"10.1016/j.jcpa.2024.10.004","DOIUrl":"10.1016/j.jcpa.2024.10.004","url":null,"abstract":"<div><div>A young free-ranging black-horned capuchin (<em>Sapajus nigritus</em>) with a history of ataxia, anisocoria, diminished threat and pupil reflexes and increased cranial circumference was referred for evaluation to the Medicine and Wildlife Conservation Section, Federal University of Paraná, Paraná, Brazil. Due to the clinical presentation and radiographic findings of hydrocephalus, euthanasia was performed. Necropsy revealed a dark red mass (1.5 × 1.8 cm) in the region of the third ventricle and marked dilation of the lateral ventricles. Histopathological findings were characterized by proliferation of ciliated round cells with eosinophilic cytoplasm, as well as the formation of ependymal rosettes and pseudorosettes. In some areas the cells contained brown cytoplasmic pigment, which stained with Fontana-Masson. The neoplastic cells were immunoreactive for glial fibrillary acidic protein and negative for pancytokeratin. Considering the anatomopathological and immunohistochemical findings, the diagnosis was ependymoma grade II with melanocytic features, which is the first report of this neoplasm in any member of the genus <em>Sapajus</em>.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 66-70"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142643980","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}

{"title":"Forensic wound age estimation in dog tissue correlated with newly formed collagen fibres: a retrospective study","authors":"Monika Hilbe ,&nbsp;Titus Sydler ,&nbsp;Leoni Hugentobler ,&nbsp;Oliver Heller ,&nbsp;Tanja Stadler ,&nbsp;Jasmin Kuratli","doi":"10.1016/j.jcpa.2024.10.006","DOIUrl":"10.1016/j.jcpa.2024.10.006","url":null,"abstract":"<div><div>Parameters for wound age estimation are essential in forensic pathology but difficult to assess. With this retrospective study, wound age parameters in canine skin wounds were assessed with archive material of known age. Haematoxylin and eosin (HE) staining as standard, Prussian blue, Van Gieson (VG) and multiple other special stains were used as well as various immunohistochemistry (IHC) tests. Collagen fibre formation examination included HE staining but also immunolabelling for elastin and collagen I. Collagen fibre formation was further assessed by polarization in HE and VG. HE staining, erythrophagocytosis and presence of haemoglobin decay products in the Prussian blue stained-slides proved to be useful tools in wound age estimation in the early phase of wound repair of less than 5 days. The earliest detection of newly formed collagen was possible in 5-day-old wounds with HE and VG staining. Collagen I reactivity by IHC was weak at this time point, moderate to strong in the lesions older than 10 days and up to 30 days and strong in the lesions older than 3 months. Very slight polarization of collagen fibres was observed at 6 days, becoming stronger in wound lesions of 10–14 days and up to 30 days and reaching the same intensity as normal tissue in a 3-month-old lesion. The morphology of newly formed collagen fibres, utilizing HE and VG staining and polarization as well as collagen I IHC, which proved to be the most important parameters, correlated with distinguishable time points in the available cases of known wound age.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 81-90"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142707433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Uveal iridophoroma in a betta fish (Betta splendens)","authors":"Lisa Crevoiserat ,&nbsp;Nina Katzenstein ,&nbsp;Elise E.B. LaDouceur","doi":"10.1016/j.jcpa.2024.09.006","DOIUrl":"10.1016/j.jcpa.2024.09.006","url":null,"abstract":"<div><div>Chromatophoromas are neoplasms arising from pigment cells in vertebrates. Iridophoromas are a type of chromatophoroma that are reported in several teleost species. There are multiple case reports of this diagnosis in betta fish (<em>Betta splendens</em>), but all previously reported cases originated from the skin. This is the first report of an intra-ocular iridophoroma. An adult betta fish had buphthalmia of the right eye and enucleation was performed. The fish survived surgery but was found dead 2 days later. The eye and entire body were examined histologically, and the right eye was also examined ultrastructurally. Histologically, the uveal tract of the right eye was unilaterally and markedly expanded by a neoplasm that expanded and obliterated the iris and choroid and regionally invaded the cornea and sclera. The neoplasm was composed of spindle cells that contained pale green, birefringent, crystalline granules (iridophores). Transmission electron microscopy revealed that neoplastic cells contained a single elongated nucleus and one or more thin cytoplasmic bundles of reflecting plates that were oriented parallel to the basal lamina, further confirming the diagnosis of iridophoroma. This is the first reported case of an iridophoroma arising from the uveal tract. Most cases of iridophoromas and other chromatophoromas in fish are reported as benign. However, there are no established histological criteria of malignancy in these neoplasms. Despite the bland cellular morphology, most reported cases of iridophoromas and other chromatophoromas in bettas (including this case) had substantial tissue invasion and/or destruction. This suggests that iridophoromas and chromatophoromas in bettas may have local invasion, consistent with malignancy, despite bland cytological features.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 71-75"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142647982","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}

{"title":"Hyperkeratotic gastritis in two-toed sloths (Choloepus didactylus) from wildlife rescue","authors":"Washington A. Pereira ,&nbsp;David F. Conga ,&nbsp;Antônio M. Costa ,&nbsp;Adriana C. Jaques ,&nbsp;Alexsandro P. Damasceno ,&nbsp;Samara C. Loura ,&nbsp;Pedro H. Portela ,&nbsp;Andressa B. Menezes ,&nbsp;Ana S. Ribeiro","doi":"10.1016/j.jcpa.2024.10.002","DOIUrl":"10.1016/j.jcpa.2024.10.002","url":null,"abstract":"<div><div>Xenarthran mammals of the suborder Folivora are arboreal species that feed mainly on leaves and <em>Cecropia</em> spp, an abundant plant in the Brazilian Amazon region, is favoured. The stomach of sloths represents 20–30% of their body weight and is adapted to gastric fermentation of plant material. These anatomical and physiological adaptations can be altered by many factors when confined to captivity, which favours fatal gastric conditions. The objective of this study was to describe the gastric anatomopathological lesions in three two-toed sloths (<em>Choloepus didactylus</em>) from a wildlife rescue centre. Necropsy revealed wide variation in the thickness of the gastric mucosa, with large areas having a papilliform appearance. Histologically, hyperkeratinization of the stratified squamous epithelium of the aglandular gastric region and infiltration of lymphocytic and plasmacytic cells were seen. The histopathological diagnosis was chronic hyperkeratotic gastritis, which has not previously been reported in sloths. Repeated exposure to dietary antigens, drugs, chemicals, toxins or infectious agents can initiate allergic or immune-mediated responses that can ultimately lead to chronic gastritis in these animals.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 55-58"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621428","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}

{"title":"Amyloid-producing ameloblastoma of the maxilla in a 17-year-old cynomolgus macaque (Macaca fascicularis)","authors":"Caitlin M. Culligan ,&nbsp;Brian G. Murphy ,&nbsp;Andrew N. Cartoceti ,&nbsp;Elise E.B. LaDouceur","doi":"10.1016/j.jcpa.2024.10.005","DOIUrl":"10.1016/j.jcpa.2024.10.005","url":null,"abstract":"<div><div>Amyloid-producing ameloblastomas (APAs) are a histological variant of ameloblastoma in which the neoplastic odontogenic epithelial cells are associated with the production of amyloid. This jaw-associated entity has been only rarely described in animals and purportedly does not exist in humans. This report is the first description of an APA in a primate. A 17-year-old, male, captive cynomolgus macaque (<em>Macaca fascicularis</em>) had a slowly growing mass on the left rostral maxillary region that involved the bone. The mass was first seen in 2022 associated with the left maxillary canine tooth (203) and regrew after incomplete excision and extraction of the affected canine tooth. Additional excision was performed in 2024, at which time the mass was 3.8 cm in diameter, roughly spherical, tan and hard. Histologically, the mass was composed of packets, cords, anastomosing trabeculae and plexiform ribbons of odontogenic epithelial cells embedded in abundant fibrovascular stroma. Packets of epithelial cells surrounded an abundant, apical, congophilic amyloid matrix that was variably mineralized. Odontogenic epithelium was immunoreactive to cytokeratin AE1/AE3 and had no immunoreactivity for vimentin. These findings are diagnostic for APA. This is the first report of APA in any primate, human or non-human, raising the question of whether this entity can occur in humans.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 76-80"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142707432","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}

{"title":"Spontaneous soft tissue tumours in aged mouse lemurs (Microcebus spp)","authors":"Martina Bleyer ,&nbsp;Ute Radespiel ,&nbsp;Annette Klein ,&nbsp;Annika Kollikowski ,&nbsp;Philipp Ströbel ,&nbsp;Kerstin Mätz-Rensing ,&nbsp;Eva Gruber-Dujardin","doi":"10.1016/j.jcpa.2024.10.001","DOIUrl":"10.1016/j.jcpa.2024.10.001","url":null,"abstract":"<div><div>Mouse lemurs (<em>Microcebus</em> spp) are small Madagascan strepsirrhine primates increasingly used as an animal model in ageing research. During a period of 10 years, neoplastic disease occurred in 47 grey (<em>Microcebus murinus</em>) and Goodman's (<em>Microcebus lehilahtsara</em>) mouse lemurs from a captive colony in Germany. Approximately half of these tumours appeared histologically as soft tissue tumours (STTs) with a significantly higher proportion of STTs in Goodman's mouse lemurs (87.5%) compared with grey mouse lemurs (38.5%) (<em>P</em> ≤0.025). Most STTs grew subcutaneously in old or senile animals and were commonly located on the trunk, less often on the head and rarely at visceral sites. The majority of STTs were of fibrous or myofibroblastic origin, followed by undifferentiated pleomorphic sarcomas and extraskeletal chondro-osseous neoplasia. Histological grading of malignant STTs revealed all but one as grade II or III, with more than 60% being grade III. Female mouse lemurs of both species were affected significantly more often by grade II and III tumours than males (<em>P</em> = 0.0412). This study gives a comprehensive overview of the spectrum of mesenchymal neoplastic disease in mouse lemurs and highlights some histomorphological characteristics of spontaneous STTs in this small non-human primate species.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"215 ","pages":"Pages 47-54"},"PeriodicalIF":0.8,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621430","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}