Veterinary Pathology Research Articles

Image challenge in Veterinary Pathology, answers: Fungal diseases

Image challenge in <i>Veterinary Pathology</i>, answers: Fungal diseases

Pathological Changes and Sodium Rhodizonate Test as Tools for Investigating Gunshot Wounds in Veterinary Forensic Pathology.

Gunshot wound morphology and gunshot residues (GSRs) evaluation have been poorly investigated in veterinary forensic pathology. The aims of the present study were to assess the gunshot wound morphology in animals and evaluate the detectability of lead deriving from GSRs using colorimetric techniques. To these aims, cadavers were divided into four different groups. Group A comprised eight animals who died from firearm-related injuries, while groups B and C included dog limbs shot using different shooting ranges; group D comprised dog limbs stabbed with a screwdriver. Morphological analysis was performed on all entry gunshot wounds. Lead residues were investigated using a Bullet Hole Testing Kit (BTK) and Rhodizonate Sodium histochemical staining (NaR-s). Gunshot wounds in group A showed an abrasion ring associated with hemorrhages and tissue necrosis. Groups B and C showed injuries related to the shooting range. NaR-s showed positive results in both animals that died from gunshot wounds and experimentally shot limbs. However, the number of positive cases and the pattern of lead distribution varied with the shooting range. Positive results by BTK were limited to close-contact shots in group B limbs. Our results suggest that both pathological examination and NaR tests represent valid tools for investigating gunshot wounds in veterinary pathology.

Radiographic, computed tomographic, and histologic characteristics of bone for clinically normal laying hens in a free-range housing system.

Laying hens are increasingly being kept in backyard flocks and considered family pets; however, diagnostic imaging characteristics of bone for clinically normal backyard hens are currently limited. This prospective, descriptive study was to describe radiographic, computed tomographic, and histologic characteristics of bone for a group of clinically normal laying hens housed in conditions comparable to those of backyard flocks. Sixteen 60-week-old Lohmann Brown laying hens were included. Hens were housed in a free-range unit with outdoor access at a university research and teaching farm. Hens were defined as clinically normal by the farm manager and a veterinary researcher in laying hen behavior and welfare. Findings from the horizontal beam, left lateral, sternal radiographs (n=16), postmortem, and whole-body CT scans (n=4) were recorded by a veterinary radiologist and a research technician. Histologic findings for sternal, femoral, and tibiotarsal bone samples (n=5) were recorded by a veterinary pathologist. The most frequent radiographic findings for the sternal carina (keel bone) were smoothly marginated concave deviations of the ventral margin and caudal section fractures. Multiple punctate mineral opacities (PMOs) were present in radiographs and CT images for all hens and were involved in the sternal carina and multiple other bones in the axial and appendicular skeleton. No bone abnormalities were identified in any histologic sections where PMOs were radiographically detected. Authors propose that PMOs are normal radiographic and CT findings in the bones of mature, laying hens and may represent temporary calcium reservoirs formed during osteoclastic activities.

Dynamics of Feline Sporotrichosis in Espírito Santo, Brazil: Impact of Urbanisation.

Sporotrichosis is a chronic infectious mycosis caused by traumatic implantation of Sporothrix spp., which poses a significant challenge to public health because of its zoonotic nature. It affects humans and other animals, particularly cats. This study investigated epidemiological trends and spatial distribution of feline sporotrichosis in Espírito Santo between 2017 and 2022. This study collected diagnostic data on sporotrichosis from the Veterinary Pathology Laboratory and Center for Infectious Diseases in Espírito Santo from 2017 to 2022. Statistical analyses were performed using STATA and spatial analyses were performed using ArcGIS software to create maps and identify hotspots. Kernel density estimation and directional mean statistics were applied to visualise the disease concentration and transmission trends. The results showed a significant increase in feline sporotrichosis cases in Espírito Santo from 2017 to 2022, with hotspots identified in urban and densely populated areas. Anchieta, Aracruz and Vila Velha reported the highest numbers of cases. Spatial analysis indicated a spread towards the central and northern coastal regions. This study highlights the growing threat of feline sporotrichosis in Espírito Santo, Brazil, particularly in densely populated urban areas. This underscores the urgent need for comprehensive public health strategies that address urbanisation, human-animal interactions and managing stray cat populations. Effective control measures and enhanced surveillance are crucial to mitigate the spread of this zoonotic disease. Importantly, this study provides valuable insights into the epidemiology of sporotrichosis in Brazil and offers a framework for other regions identified as emerging hotspots that face similar challenges.

Genomic and fitness consequences of a near-extinction event in the northern elephant seal.

Understanding the genetic and fitness consequences of anthropogenic bottlenecks is crucial for biodiversity conservation. However, studies of bottlenecked populations combining genomic approaches with fitness data are rare. Theory predicts that severe bottlenecks deplete genetic diversity, exacerbate inbreeding depression and decrease population viability. However, actual outcomes are complex and depend on how a species' unique demography affects its genetic load. We used population genetic and veterinary pathology data, demographic modelling, whole-genome resequencing and forward genetic simulations to investigate the genomic and fitness consequences of a near-extinction event in the northern elephant seal. We found no evidence of inbreeding depression within the contemporary population for key fitness components, including body mass, blubber thickness and susceptibility to parasites and disease. However, we detected a genomic signature of a recent extreme bottleneck (effective population size = 6; 95% confidence interval = 5.0-7.5) that will have purged much of the genetic load, potentially leading to the lack of observed inbreeding depression in our study. Our results further suggest that deleterious genetic variation strongly impacted the post-bottleneck population dynamics of the northern elephant seal. Our study provides comprehensive empirical insights into the intricate dynamics underlying species-specific responses to anthropogenic bottlenecks.

Diagnostic challenge in veterinary pathology: Otitis in a humanized NOG-EXL mouse

Diagnostic challenge in veterinary pathology: Otitis in a humanized NOG-EXL mouse

Exploring the Epidemiology of Melanocytic Tumors in Canine and Feline Populations: A Comprehensive Analysis of Diagnostic Records from a Single Pathology Institution in Italy.

MTs are prevalent in dogs, representing the most frequent oral malignancy, compared to cats, in which ocular melanomas predominate. This study investigates the canine and feline MT epidemiology (2005-2024) of cases submitted to the Veterinary Pathology Service (University of Perugia). Among the canine neoplasms, 845 (4%) were melanocytic: 329 (39%) melanocytomas; 512 (61%) melanomas. Of these, 485 (57%) were cutaneous (4% of canine cutaneous neoplasms), 193 (23%) were oral (50% of oral canine neoplasms), and 104 (12%) were mucocutaneous. The average age of affected dogs was 10 years. Older dogs were more likely to have melanomas compared to melanocytomas (p < 0.001). There were 60 (1%) feline MTs: 6 (10%) melanocytomas; 53 (88%) melanomas. Of these, 29 (48%) were cutaneous (1% of feline cutaneous tumors), 18 (30%) were ocular, and 9 (15%) were oral (22% of feline oral tumors). The average age of affected cats was 11 years. In dogs, mucocutaneous melanomas were more common compared to cutaneous ones (p < 0.05); oral melanomas were more common compared to all other sites (p < 0.001). In cats, ocular melanomas were more common compared to cutaneous ones (p < 0.05). Our study provides the MT prevalence in a selected canine and feline population, revealing MT epidemiological patterns, highlighting species-specific differences in the tumor prevalence, localization, and age distribution.

Image challenge in Veterinary Pathology, answers: Pulmonary diseases.

Image challenge in Veterinary Pathology, answers: Pulmonary diseases.

Letters or not, here we come! A communal perspective on credentials needed for a productive career in veterinary pathology.

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.

Incidence of Intra-abdominal Adhesions Following Intraperitoneal Injection of Hemostatic Products in Rabbits.

Definitive management of non-compressible intra-abdominal hemorrhage (NCIAH) currently requires a surgeon and operating room capable of performing damage control surgery. In a wartime scenario or a geographically remote environment, these may not be readily available. In this study, we sought to test the safety of 2 emerging injectable hemostatic agents (CounterFlow and Fast Onset Abdominal Management, or FOAM, poloxamer component) versus normal saline control over a prolonged monitoring duration following administration by a non-surgical provider. The Institutional Animal Care and Use Committee approved all research conducted in this study. We randomized male New Zealand white rabbits into 2 monitoring cohorts of 24 hours and 2 weeks. Each cohort contained 3 treatment groups (n = 4 rabbits/group): CounterFlow, the testable poloxamer component of FOAM, and normal saline control. We injected each treatment intraperitoneally in the left lower abdominal quadrant. Doses were 15 mL/kg for CounterFlow, 6.3 mL/kg for the poloxamer component of FOAM, and 15 mL/kg for normal saline. We conducted all injections under isoflurane anesthesia monitored by trained veterinary staff. Animals were euthanized at each cohort end point, and a veterinary pathologist blinded to treatment type performed necropsy. The primary outcome was incidence of intra-abdominal adhesions at necropsy. Quantitatively, adhesions when present were graded by the veterinary pathologist on a 1 to 4 scale, where "1" represented adhesions involving from 1 to 25% of the examined abdomen, "2" represented from 26 to 50%, "3" represented from 51 to 75%, and "4" represented from 76 to 100%. Qualitatively, adhesions present were graded by degree ("1" = minimal, "2" = mild, "3" = moderate, and "4" = severe) and chronicity ("1" = acute, "2" = subacute, and "3" = chronic). We also drew d-dimer blood values and measured body weights for each animal. Statistical analysis included either repeated measures 2-way ANOVA or a mixed-effects model (in the case of missing data) with Geisser-Greenhouse correction. We adjusted multiple comparisons using Tukey statistical hypothesis tests. In the 2-week cohort, 3 CounterFlow animals showed adhesions judged to be "1" quantitatively. Qualitatively, 2 of these were assessed as "1" for degree of adhesions and the other demonstrated a "2." On the chronicity of adhesions scale, 1 animal demonstrated a "2" and 2 demonstrated a "3." No animals in other groups (FOAM and control) demonstrated adhesions. CounterFlow-treated animals showed a statistically significant rise in d-dimer values in the 24-hour cohort only. In the 2-week cohort, CounterFlow-treated animals showed a decrease in body weight at 24 hours after injection but returned to their baseline (normal) body weights at 7 days. Findings from this study demonstrate that the tested ingredients of FOAM poloxamer component are safe for intraperitoneal injection and hold potential for further study directed toward prehospital non-compressible intra-abdominal hemorrhage management by non-surgical providers. Although CounterFlow produced abdominal adhesions in 3 of 4 rabbits in the 2-week cohort, these were determined to be "minimal" or "mild" in degree.

Ronald John Roberts.

A veterinary pathologist, author, editor, teacher and mentor to many young vets and fish health professionals; he was a talented veterinarian who applied veterinary science to aquaculture.

Histopathological and Immunohistochemical Studies on Endocrine Glands of Dogs with Special Emphasis on the Immunoexpression of β-cells of the Pancreas

The aim of this study to evaluate the histopathological, histochemical and immunohistochemical changes of the endocrine glands namely, thyroid, pancreas and adrenal gland in dogs submitted to routine necropsy. A total number of 45 endocrine samples were collected from 15 carcasses of dogs received at Department of Veterinary Pathology, Madras Veterinary College, Chennai- 600 007 were chosen for the present study, namely thyroid, pancreas and adrenal gland. The tissue samples were collected in 10% neutral buffered formalin. Tissues were processed after 48 hours as per recommended procedure and 3 µm thickness sections were made and stained with haematoxylin and eosin for histopathological evaluation. The special stains like Masson’s trichrome and Picrosirius red were used to assess the extent of replacement with collagen fibers. Immunohistochmical protocol was followed as per the manufactured recommendation (Pathnsitu, USA).The histopathological changes recorded in the pancreas included vacuolar changes (2/15), necrosis (2/15), periductular fibrosis (1/15), perivascular fibrosis (1/15), congestion (5/15), hemorrhages (3/15) and inflammatory changes (1/15) while in the adrenal glands included diffuse cortical hyperplasia (4/15) succeeded by nodular hyperplasia (3/15), adrenalitis (2/15), hyperaemia (2/15), hemorrhages (1/15) and atrophy (1/15). Histopathological examination of thyroid revealed atrophy of follicles suggesting thyroiditis (3/15), presence of follicular epithelial cells which were found separated from the basement membrane with cellular debris in the lumen indicating necrosis (2/15) and presence of large cystic gaps with eosinophilic proteinaceous material consistent with cystadenoma(2/15). The remaining samples showed hemorrhages (2/15), perivascular fibrosis (1/15) and congestion (2/15). However no histological alterations were noticed in 3 cases (3/15). Immunohistochemistry revealed that pancytokeratin was expressed by all epithelial cells including ducts. The expression of insulin was noticed in all the cases indicating that no reduction of â cells in all the above said pathological conditions.

Endoparasites of rabbits and hares.

Nematode, cestode, protozoan, microsporidian, and pentastomid parasites affect domesticated and wild rabbits, hares, and jackrabbits of the genera Brachylagus, Lepus, Oryctolagus, Pentalagus, and Sylvilagus. Some endoparasite infections are of limited or no significance, whereas others have potentially profound consequences. Accurate identification of endoparasites of rabbits, hares, and jackrabbits is an important facet of the work of veterinary pathologists engaged in lagomorph pathology. Here I review endoparasites from the pathologist's perspective, focusing on pathogenesis, lesions, and implications of infection. Stomach nematodes Graphidium strigosum and Obeliscoides cuniculi are infrequently pathogenic but may cause gastritis and gastric mucosal thickening. Nematodes Passalurus ambiguus, Protostrongylus spp., Trichostrongylus spp., and Trichuris spp. are rarely associated with disease. Adult Capillaria hepatica (syn. Calodium hepaticum) nematodes and non-embryonated eggs cause granulomatous hepatitis in wild Oryctolagus cuniculus and Lepus europaeus, resulting in multifocal, off-white, hepatic lesions, which may be misdiagnosed as hepatic eimeriosis. When the rabbit is an intermediate host for carnivore cestodes, the space-occupying effects of Cysticercus pisiformis and Coenurus serialis may have pathologic consequences. Eimeria stiedai is a major cause of white-spotted liver in O. cuniculus, particularly in juveniles. Enteric coccidiosis is a noteworthy cause of unthriftiness in young animals, and frequently manifests as diarrhea with grossly appreciable multifocal off-white intestinal lesions. O. cuniculus is the natural host for the zoonotic microsporidian Encephalitozoon cuniculi. Infection may be acute and focused mainly on the kidneys, or it may follow a chronic disease course, frequently with neurologic lesions. A latent carrier status may also develop.

Prevalence of bovine respiratory viruses in cattle calves in Kangra district of Himachal Pradesh

Respiratory diseases causing pneumonia are the 2nd leading cause of mortality in bovine calves and are primarily caused by viral pathogens. The present study was undertaken in cattle calves under twelve months of age for detecting four respiratory viruses, viz. bovine herpes virus-1 (BoHV-1), bovine viral diarrhoea virus (BVDV), bovine respiratory syncytial virus (BRSV), and bovine parainfluenza virus type 3 (BPI3), using a commercially available multiscreen antigen ELISA kit. A total of 30 cattle calves necropsied at the Department of Veterinary Pathology, DGCN COVAS, CSKHPKV, Palampur, from June 2021 to June 2022 were screened. The samples of lung tissues and nasal turbinates were collected and stored at –20°C until further processing. The collected tissue samples were homogenised and processed as per the standard protocol. Among the 30 necropsied samples, BoHV-1 and BRSV were detected in 17/30 (56.67%) samples, BPI3 was detected in 14/30 (46.67%) samples, and BVDV was detected in 8/30 (26.67%) samples. 5/30 (16.67%) samples were found positive for all four viruses. Moreover, three viruses were concurrently detected in 4/30 samples (13.33%), and two viruses were present in 10/30 samples (33.33%). Additionally, a single virus was detected in 4/30 samples (13.33%). In conclusion, the present investigation reveals the substantial presence of respiratory viruses in the respiratory tract of cattle calves. The result indicates a complex pattern of co-infections of different viruses, emphasising the need for effective surveillance and management strategies to address the diverse viral dynamics affecting bovine respiratory health.

A brief history of the American College of Veterinary Pathologists (2009-2024).

A brief history of the American College of Veterinary Pathologists (2009-2024).

Deep Learning-based Modeling for Preclinical Drug Safety Assessment.

In drug development, assessing the toxicity of candidate compounds is crucial for successfully transitioning from preclinical research to early-stage clinical trials. Drug safety is typically assessed using animal models with a manual histopathological examination of tissue sections to characterize the dose-response relationship of the compound - a time-intensive process prone to inter-observer variability and predominantly involving tedious review of cases without abnormalities. Artificial intelligence (AI) methods in pathology hold promise to accelerate this assessment and enhance reproducibility and objectivity. Here, we introduce TRACE, a model designed for toxicologic liver histopathology assessment capable of tackling a range of diagnostic tasks across multiple scales, including situations where labeled data is limited. TRACE was trained on 15 million histopathology images extracted from 46,734 digitized tissue sections from 157 preclinical studies conducted on Rattus norvegicus. We show that TRACE can perform various downstream toxicology tasks spanning histopathological response assessment, lesion severity scoring, morphological retrieval, and automatic dose-response characterization. In an independent reader study, TRACE was evaluated alongside ten board-certified veterinary pathologists and achieved higher concordance with the consensus opinion than the average of the pathologists. Our study represents a substantial leap over existing computational models in toxicology by offering the first framework for accelerating and automating toxicological pathology assessment, promoting significant progress with faster, more consistent, and reliable diagnostic processes.

Necropsy as an Important Diagnostic Step in Veterinary Pathology: The Past, Present, and Future Perspectives

Necropsy as an Important Diagnostic Step in Veterinary Pathology: The Past, Present, and Future Perspectives

Histopathological and Immunohistochemical Studies of a Spontaneous Case of Pulmonary Adenomatosis in an Adult Ram: A Case Report

Aim: The present study aimed to describe histopathological findings and immunohistochemical expression of proliferating cell nuclear antigen (PCNA) in a spontaneous case of pulmonary adenomatosis in an adult ram. Case Presentation: A carcass of an adult ram was presented for necropsy in the Post-mortem Hall of the Department of Veterinary Pathology, College of Veterinary Sciences of the Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar with a history of respiratory distress. A detailed necropsy was performed. The tracheal mucosa showed mild congestion. The lungs were pale and firm in consistency. On histopathological examination, nasal turbinate and trachea both showed the vascular changes along with mild infiltration of mononuclear cells. The sections of lungs revealed pulmonary adenocarcinoma characterized by the presence of cuboidal to low columnar epithelial cells forming acinar or papillary-like structures in the parenchyma and surrounded by the normal alveoli. Areas of necrosis along with infiltration of mononuclear cells were also evident. An Immunohistochemical study of the lung sections revealed mild to moderate immunopositive reactivity for the PCNA in the nuclei of neoplastic cells of adenocarcinoma. It indicated the proliferative activity of neoplastic cells. Conclusion: Based on histopathological examination, the present case was diagnosed as pulmonary adenomatosis. PCNA expression indicated the presence of actively proliferating neoplastic cells.

Preclinical evaluation of transaxial intraputaminal trajectory for enhanced distribution of grafted cells in Parkinson's disease.

The objective of this study was to develop and evaluate the feasibility and safety of a novel transaxial surgical approach for the delivery of human induced pluripotent stem cell-derived dopaminergic neuroprogenitor cells (DANPCs) into the putamen nucleus using nonhuman primates and surgical techniques and tools relevant to human clinical translation. Nine immunosuppressed, unlesioned adult cynomolgus macaques (4 females, 5 males) received intraputaminal injections of vehicle or DANPCs (0.9 × 105 to 1.1 × 105 cells/µL) under real-time intraoperative MRI guidance. The infusates were combined with 1-mM gadoteridol (for intraoperative MRI visualization) and delivered via two tracks per hemisphere (ventral and dorsal) using a transaxial approach. The total volumes of infusion were 25 µL and 50 µL for the right and left putamen, respectively (infusion rate 2.5 µL/min). Animals were evaluated with a battery of clinical and behavioral outcome measures and euthanized 7 or 30 days postsurgery; full necropsies were performed by a board-certified veterinary pathologist. Brain tissues were collected and processed for immunohistochemistry, including against the human-specific marker STEM121. The optimized surgical technique and tools produced successful targeting of the putamen via the transaxial approach. Intraoperative MR images confirmed on-target intraputaminal injections in all animals. All animals survived to scheduled termination without clinical evidence of neurological deficits. The first 4 animals to undergo surgery had mild brain swelling noted at the end of surgery, of which 3 had transient reduced vision; administration of mannitol therapy and reduced intravenous fluid during the surgical procedure addressed these complications. Immunostaining against STEM121 confirmed the presence of grafted cells along the injection track within the targeted putamen area of DANPC-treated animals. All adverse histological findings were limited in scope and consistent with surgical manipulation, injection procedure, and postsurgical inflammatory response to the mechanical disruption caused by the cannula insertion. The delivery system, injection procedure, and DANPCs were well tolerated in all animals. Prevention of mild brain swelling by mannitol dosing and reduction of intravenous fluids during surgery allowed visual effects to be avoided. The results of the study established that this novel transaxial approach can be used to correctly and safely target cell injections to the postcommissural putamen and support clinical investigation.

A Severe Clinical Case of Theileriosis with Terminal Wasting in Adult Cattle: A Veterinary Clinical and Pathology Case Report

This veterinary clinical and pathology case report describes a severe clinical case of theileriosis in adult cattle with prolonged recumbency and terminal wasting because of complications due to chronic theileriosis in two adult (2-year-old) Jersey-Friesian Cross. The case was referred to the large animal clinic of the University Veterinary Hospital (UVH), Faculty of Veterinary Medicine, Universiti Putra Malaysia (UPM). The animals were presented as recumbent, dull, depressed, hypothermic, dehydrated, and cachexic. There were poor responses of the patients to fluid therapy and non-steroidal anti-inflammatory treatments, and they both died within 24 hrs of clinical presentation. Haematology (complete blood count and serum biochemistry) results revealed haemoconcentration and faecal examinations were negative for liver fluke infestation and blood smear examination was positive for intraerythrocytic piroplasms of Theileria (0.01% parasitaemia). Post-mortem examination further revealed advanced cachexia, generalised serous atrophy of fat, hepatomegaly, hepatic congestion, pulmonary congestion, and pulmonary oedema. Histological findings revealed atrophy of the hepatic cord, hepatic congestion, splenic hemosiderosis, pulmonary oedema and congestion. The clinicopathological findings supported an aetiological diagnosis of a severe clinical case of Theileriosis with terminal wasting because of complications due to chronic Theileriosis infection.