Idiopathic focal eosinophilic enteritis associated with ileocaecal and ileal obstruction in a 10-year-old warmblood gelding

A 10-year-old, 600-kg, warmblood gelding was referred due to persistent colic, non-responsive to medical treatment. Diagnostic evaluation revealed abdominal distention, tachycardia and distended small intestines. Preoperative blood testing revealed an increased packed cell volume and normal total white cell count, whereas an abdominocentesis revealed raised peritoneal fluid lactate. Exploratory laparotomy was performed and revealed a circumferential band of thickened tissue and hyperaemia in the distal jejunum, as well as marked wall thickening of the distal ileum and ileocaecal valve, leading to complete luminal obstruction. Due to financial constraints and complications associated with jejuno-caecostomy, the owner requested the horse to be humanely euthanased. Postmortem examination findings revealed a circumferential constriction of the distal ileum and ileocaecal valve. Histopathology of the affected segments was characterised by a large population of eosinophils within the mucosa, submucosa and muscularis layers in conjunction with severe submucosal oedema. A diagnosis of idiopathic focal eosinophilic enteritis was made.https://wileyonlinelibrary.com/journal/vrc2hj2023Companion Animal Clinical StudiesParaclinical Science

Fatal congenital peritoneopericardial diaphragmatic hernia in a sable antelope (Hippotragus niger) calf

Congenital peritoneopericardial diaphragmatic hernia was diagnosed in a 2-week-old sable antelope (Hippotragus niger) calf with subsequent fatal acute heart failure. Histopathological examination of the lung, liver and heart revealed lesions supportive of acute heart failure that consisted of pulmonary oedema, periacinar hepatocellular necrosis and myocardial degeneration and necrosis. The external pressure on the coronary arteries by the liver and abomasum most likely resulted in ischaemic injury of the cardiomyocytes and the resultant acute heart failure.https://wileyonlinelibrary.com/journal/vrc22022-06-13hj2022Centre for Veterinary Wildlife StudiesParaclinical Science

The pathology of the spleen in lethal canine babesiosis caused by Babesia rossi

To provide useful information based on the macropathology, histopathology and immunohistochemical investigation in the spleens of dogs with Babesia rossi infection. Control spleens were collected from four healthy dogs euthanized for welfare reasons. Nine dogs that died naturally because of a mono‐infection with Babesia rossi were selected for the diseased group. One haematoxylin‐and‐eosin–stained section of splenic tissue from each of the infected and control dogs was examined under the light microscope. Immunohistochemical markers were applied to characterize different immunocyte populations. The application of analytic software enabled semi‐quantitative comparison of leucocyte subpopulations. Routine splenic histopathology revealed diffuse intermingling of white and red pulp from infected dogs with a clear loss of distinction between these zones. Immunohistochemistry revealed an increase in the proportion of tissue resident and bone marrow origin macrophages in the infected spleens. Apart from a few remnant lymphocytes within the peri‐arteriolar lymphatic sheaths and follicles, the majority of the immunocytes redistributed to the red pulp, supporting the observation of white and red pulp intermingling. The majority of our findings are in agreement with histomorphological descriptions of the spleen in a variety of noncanid mammalian hosts with lethal malaria or babesiosis.The National Research Foundationhttp://www.wileyonlinelibrary.com/journal/pim2021-03-02hj2021Companion Animal Clinical StudiesParaclinical Science

Isolation of a multidrug-resistant Escherichia coli pathotype Stx2:Cnf1:Cnf2:Eae as a potential cause of hemorrhagic diarrhea and secondary septicemia in a dog

Escherichia coli is a member of the family Enterobacteriaceae and is a commensal in the intestine of many animals as well as humans. Most strains are of low virulence. A dog developed vomiting and hemorrhagic diarrhea after surgery and died despite treatment. Postmortem examination revealed hemorrhagic gastroenteritis and colitis. A multidrug-resistant E. coli, with virulence factors Shiga-toxin–producing gene, stx2, eae gene, and cytotoxic necrotic factors CNF-1 and CNF-2, was isolated from internal organs. E. coli can easily acquire new genes for virulence factors and antimicrobial resistance as demonstrated by this isolate with characteristics of both enterohemorrhagic E. coli and necrotoxigenic E. coli. In addition, the isolate was resistant to all beta-lactam antibiotics tested, as well as to enrofloxacin by a disk diffusion methodology. Broth-based minimum inhibitory concentration analysis confirmed resistance to amoxicillin (>32 μg/mL), enrofloxacin (>32 μg/mL), fosfomycin (>128 μg/mL), and neomycin (>32 μg/mL). The discovery of such strains is a cause for concern given that E. coli can be shared by companion animals and their human owners.https://jvdi.sagepub.comhj2022Paraclinical SciencesVeterinary Tropical Disease

Mortality rates and survival analysis of owned, free-roaming dogs in a resource-limited community, Bushbuckridge, South Africa

Canine rabies can be successfully controlled in dogs through mass vaccination. In populations of free-roaming dogs in resource-limited settings, the maintenance of herd immunity through vaccination is challenged by the high population turnover. Understanding and describing mortality in these populations may therefore assist in the control of rabies. The objective of this study was to determine the rates and causes of mortality in owned, free-roaming dogs in Hluvukani village, Bushbuckridge, South Africa, from May 2014 through July 2015. From the Health and Demographic Surveillance System in Dogs in Hluvukani village, we followed a nested cohort of dogs one year and older over a 12-month period and puppies born to the cohort for 120 days, from May 2014. Deaths were recorded and investigated through verbal autopsy and post-mortem examination. Survival rates from enrolment (adults) or from birth (puppies) were compared using Cox proportional hazard regression models. Of the cohort of 367 adult dogs (203 males and 164 females), 27 died during the follow-up period. The mortality rate was 78 per 1,000 dog-years in the cohort. Adult females had a shorter survival time from enrolment (mean = 341.7 days) compared to adult males (mean = 356 days; p = 0.05). No difference in survival was detected between age groups. Enrolled litters were 62 and 329 enrolled puppies, 135 died before 120 days of age. Mortality in puppies was high with 2,390 deaths per 1,000 dog-years recorded, and a mean survival time of 60 days. No difference in survival was observed between males and females (p = 0.3). In adults and puppies, causes of death were identified as natural (43%), non-natural (53%) and euthanasia (4%). Mortality was low in adult dogs, but very high in the puppies. Despite high population turnover through births and deaths, the vaccination coverage was still sufficient to prevent rabies outbreaks in the village.Poster presented at the University of Pretoria, Faculty of Veterinary Science Faculty Day, August 25, 2016, Pretoria, South Africa.ab201

Sinonasal meningioma in a Siberian tiger (Panthera tigris altaica)

Meningiomas are the most common primary brain tumour in dogs and cats. However, whilst there are numerous reports of extracranial (spinal, orbital and sinonasal) meningiomas in the dog, there have only been a few case reports of spinal meningiomas, and no post-mortem confirmed orbital or sinonasal meningiomas in cats. In this report, a 20-year-old captive tiger (Panthera tigris altaica) with a history of chronic ocular inflammation resulting in enucleation, spontaneously developed tetanic convulsions (epileptic seizures) that over a 2-year period resulted in a gradually worsening condition and the animal was eventually euthanized. At autopsy, a focal, expansile, neoplastic mass was found in the caudal nasal cavity midline, abutting the cribriform plate and slightly compressing the calvarium. Histological analysis revealed nasal turbinates attached to a wellcircumscribed expansile multi-lobular mass consisting of interlacing whorls and streams of neoplastic cells supported by a variably fibrous to microcystic collagenous matrix displaying rare psammoma bodies. The diagnosis was sinonasal transitional meningioma. This is the first report of a captive wild felid with an extracranial meningioma, specifically a tiger with a sinonasal transitional meningioma.The Wellcome Trust.https://www.mdpi.com/journal/vetsciam2023Centre for Veterinary Wildlife StudiesParaclinical Science

The pathology of the spleen in canine babesiosis

The spleen is the largest secondary lymphoid organ in the body and therefore not only does it perform many hematopoietic functions but it also mounts an immunological response to blood-borne antigens. Malaria and babesiosis, both haemoparasitic diseases, reveal many similarities in clinical disease, pathogenesis and post mortem findings and are often compared to one another. Both are protozoan diseases transmitted by mosquitoes and ticks, respectively. Malaria has been more extensively studied than babesiosis. Information regarding the effect of babesiosis on various hosts is limited, particularly with respect to the spleen. The purpose of this study was to investigate the effect of Babesia rossi on the spleen of dogs. We aimed to provide a detailed histomorphological analysis of infected spleens, with the addition of immunohistochemical labelling of leukocyte subsets. One section of splenic tissue from each of 9 Babesia rossi-infected dogs and 4 healthy control dogs was examined under the light microscope. Immunohistochemical markers were applied to infected and control spleens in order to characterise different immunocyte populations. Markers included CD3 (T lymphocytes), CD20 (mature B lymphocytes and normal dog plasma cells), Mum1 (plasma cells), Pax-5 (immature B lymphocytes), Mac387 (monocytes-macrophages of bone marrow origin) and CD204 (resident tissue macrophages). The application of analytic software enabled us to compare leukocyte subpopulations in infected and control spleens in a semi-quantitative manner. Routine histopathology revealed diffuse intermingling of the white and red pulp in Babesia rossi-infected spleens with a clear loss of distinction between these zones. The merging of zones was accentuated by outspoken white pulp dissolution with no discernible germinal centres, mantle or marginal zones. Immunohistochemical labelling revealed a significant increase in the proportion of tissue resident macrophages as well as macrophages of bone marrow origin in the infected spleens. In addition, apart from a few remnant lymphocytes within the peri-arteriolar lymphatic sheaths and follicles, the majority of immunocytes had redistributed to the red pulp, supporting the observation of white and red pulp intermingling. Our study produced novel insights into the pathology of the spleen in canine babesiosis. The majority of our findings are in agreement with histomorphological descriptions of the spleen in a variety of hosts with malaria. The exact causes, consequences and implications for disease pathogenesis require further investigation.Dissertation (M.Med.Vet)--University of Pretoria, 2019.Paraclinical SciencesM.Med.VetUnrestricte

Metastatic extraskeletal myxoid chondrosarcoma in a greater kudu (Tragelaphus strepsiceros)

Extraskeletal myxoid chondrosarcoma was diagnosed on the ventral abdomen of a kudu with metastasis to the omentum and lungs. Histopathological examination of the large (20 cm × 10 cm) primary, multinodular, moderately cellular neoplastic mass was characterised by neoplastic mesenchymal cells arranged in strands and bundles, interspersed by multiple foci of cartilage immersed in a myxoid matrix. The neoplastic cells revealed diffuse vimentin and S100 positivity and the myxoid matrix was positive with Alcian blue. The microscopic examination in addition to the Alcian Blue and immunohistochemistry findings confirmed the diagnosis.http://vetrecordcasereports.bmj.comhj2020Paraclinical Science

Salmonella entericaserovar Typhimurium bacteraemia in a puppy with canine parvoviral enteritis

A 12-week-old female intact, pit bull terrier cross breed puppy presented with vomiting and haemorrhagic diarrhoea. Phagocytosed bacterial rods were observed on peripheral and central blood smears. A commercially available canine parvovirus ELISA test and subsequent electron microscopy for viral particles both tested negative on faecal sampling. The owners declined treatment and the puppy was euthanased. The postmortem revealed enteric necrosis, purulent meningoencephalitis, necropurulent hepatitis and diffuse interstitial pneumonia, with heavy Salmonella enterica serovar Typhimurium growth on blood and tissue culture. The Salmonella species were sensitive to most commonly used antimicrobials including ampicillin. Canine parvovirus enteritis was diagnosed by positive canine parvovirus specific immune-peroxidase staining of intestinal tissue sections. To the authors’ knowledge, this is the first paper to describe canine parvoviral enteritis complicated by a salmonella bacteraemia, and the detection of a bacteraemia on a peripheral blood smear in a live dog.https://bvajournals.onlinelibrary.wiley.com/journal/20526121hj2021Companion Animal Clinical StudiesParaclinical Science