Enzootic calcinosis in Toggenburg goats in New Zealand.

CASE HISTORY: Necropsies on Toggenburg goats culled from a small farm in the Manawatu district of New Zealand, performed at Massey University (Palmerston North, NZ) over a period of 29 years (1991-2019), revealed soft tissue mineralisation, particularly of cardiovascular tissues. The farm spans 10 acres and runs between 15 and 30 Toggenburg goats. The goats are predominantly on pasture comprising a variety of types. PATHOLOGICAL FINDINGS: Necropsies were performed on all adult goats (n = 45) that died or were euthanised. Histopathology was performed on 42 goats (93%), of which 33 (73%) included sufficient tissues diagnostically relevant to soft tissue mineralisation. The most significant gross findings were in various arteries, with the aorta most commonly affected, followed by the heart and lungs. The aortic intima showed prominent, multifocal to coalescing, raised, wrinkled, white plaques. Microscopically there were multiphasic lesions of mineralisation, chondroid, and osseous metaplasia in the elastic arteries, aorta, heart and lungs. A lumbar vertebra from one goat had prominent, basophilic, fibrillar, tangled matrix lining Haversian canals and lamellae. LABORATORY FINDINGS: Blood samples were collected from 15 adult goats in the affected herd and from 10 adult Toggenburg goats from an unaffected herd. Samples were collected by jugular venipuncture at 2-month intervals for 12 months (April 2018-March 2019). Concentrations of calcium, phosphorus, 25-hydroxyvitamin D2 and D3 (25OHD2, 25OHD3) in serum were analysed. The concentration of total 25OHD in serum was 34.2 (95% CI = 18.9-49.4) nmol/L (p < 0.001) higher in goats from the affected herd than in goats from the unaffected herd. Serum 25OHD2 concentration was 46.2 (95% CI = 39.2-53.2) nmol/L higher (p < 0.001) in goats from the affected herd compared to the unaffected herd. Serum Ca concentrations in affected goats were 0.101 (95% CI = 0.005-0.196) mmol/L higher (p = 0.039) than unaffected goats, but remained within the reference range. There was no evidence of a difference in serum 25OHD3 and P concentration between the herds. VEGETATION SURVEY: All paddocks on the property were surveyed every 2 months along evenly spaced line transects, and then further traversed perpendicularly to form a grid. No known calcinogenic species were identified. Known plant sources of vitamin D identified on the farm included mushrooms (species not defined), Dactylis glomerata, lichen, pine pollen, and algae. DIAGNOSIS: Soft tissue mineralisation and enzootic calcinosis. CLINICAL RELEVANCE: Veterinarians are alerted to the possibility of either enzootic calcinosis in goats and the potential occurrence of calcinogenic plants in New Zealand; or chronic vitamin D toxicosis of non-plant origin.

White snakeroot poisoning in goats: Variations in toxicity with different plant chemotypes.

Tremetone and possibly other benzofuran ketones are believed to be the toxic compounds in white snakeroot. However, disease has not been reproduced with purified toxins and the concentrations of the benzofuran ketones in white snakeroot populations that cause toxicosis have not been documented. The objectives of this study were to compare the toxicity of seven plant populations, better characterize the clinical and pathologic changes of poisoning, and correlate intoxication with benzofuran ketone content. Four of the seven white snakeroot collections were toxic at the dose and duration used in the study. Affected goats became exercise intolerant, had significant serum enzyme changes and histological lesions in the large appendicular muscles. The incidence and severity of poisoning was not correlated with total doses of tremetone or total benzofuran ketone concentrations suggesting they may not be closely involved in producing toxicity and the possible involvement of an unidentified toxin. The results also demonstrate that white snakeroot populations vary chemically and toxicologically.

Liver biopsy histopathology for diagnosis of Johne's disease in sheep.

Sheep with Johne's disease develop epithelioid macrophage microgranulomas, specific to Mycobacterium avium subsp. paratuberculosis (Map) infection, in the terminal ileum, mesenteric lymph nodes, and organs distant to the alimentary tract such as the liver. The objectives of this study were to determine whether liver pathology was present in ewes affected by Map and whether liver cores provide adequate tissue for this potential diagnostic marker. One hundred and twenty-six adult, low body condition ewes were euthanized, necropsied, and underwent simulated liver biopsy. Ileal lesions typical of Map were found in 60 ewes. Hepatic epithelioid microgranulomas were observed in all ewes with Type 3b (n = 40) and 82% (n = 11) with Type 3c ileal lesions. None were found in ewes unaffected by Map or with Type 1, 2, or 3a ileal lesions. Liver biopsy core samples provided adequate tissue for histopathology with a sensitivity and specificity of 96% (95% confidence interval [CI], 0.87-0.99) and 100% (95% CI, 0.95-1), respectively for detection of types 3b and 3c ileal lesions.

Pathology of Brucella ovis infection in red deer stags (Cervus elaphus).

AIM: To describe the pathology of the reproductive tract of red deer stags with active Brucella ovis infection and in stags in which B. ovis infection had resolved. METHODS: Twenty-three red deer stags of varying history were slaughtered and their epididymides and accessory sex glands examined grossly and by histopathology. At the time of slaughter five of the stags had an active B. ovis infection of 24-55 days duration following exposure to infected rams, 10 stags had been experimentally infected with B. ovis by intravenous inoculation 649 days previously and had developed an active infection but the bacterial infection had resolved at least 308 days prior to slaughter, and eight stags had not been exposed to B. ovis at any time. RESULTS: Of the five stags with an active infection, one had gross enlargement of the epididymides that could be detected by scrotal palpation. Histological lesions in all five stags included mild to severe, predominantly non-suppurative epididymitis, vesiculitis, prostatitis and ampullitis, with neutrophil exudation in associated glandular ducts. Additional lesions in the epididymides were spermatic granulomas and epithelial hyperplasia with intra-epithelial cyst formation. Of the 10 stags in which the bacterial infection had resolved, two had gross enlargement of the epididymides. The histological lesions were similar to those in stags with active infection but were generally milder, with increased periductal scar tissue in the epididymides. The lesions seen in stags resembled those seen in rams with B. ovis infection but they were usually less florid and had fewer plasma cells. No gross abnormalities or histopathological lesions were detected in the non-infected stags. CONCLUSIONS: Only a small percentage of red deer stags infected with B. ovis develop lesions of epididymitis that can be detected by scrotal palpation. Gross and histological lesions of the genital tract of stags associated with B. ovis infection are similar to the lesions seen in rams. Lesions in stags persist for >300 days after the bacterial infection has resolved. CLINICAL RELEVANCE: Brucella ovis infection should be considered when there are gross lesions of epididymitis or histological evidence of inflammation in the epididymides or accessory sex glands of red deer stags. Retrospective diagnosis of B. ovis in stags could be achieved by histological examination of the reproductive organs.

Effect of tissue processing on assessment of endoscopic intestinal biopsies in dogs and cats.

BACKGROUND: Prior studies failed to detect significant association between hypoalbuminemia and small intestinal lesions. HYPOTHESIS: Use of pictorial templates will enhance consistency of interpathologist interpretation and identification of intestinal lesions associated with hypoalbuminemia. ANIMALS: Tissues from 62 dogs and 25 cats examined as clinical cases at 7 referral veterinary practices in 4 countries. METHODS: Retrospective, observational study. Histopathology slides from sequential cases undergoing endoscopic biopsy were examined by 4 pathologists by pictorial templates. Changes for 9 microscopic features were recorded as normal, mild, moderate or severe, and 2- and 4-point scales were tested for consistency of interpretation. Logistic regression models determined odds ratios (OR) of histologic lesions being associated with hypoalbuminemia while kappa statistics determined agreement between pathologists on histologic lesions. RESULTS: There was poor agreement (kappa = -0.013 to 0.3) between pathologists, and institution of origin of slides had effect (kappa = 1.0 for 3 of 4 lesions on slides from Institution 5) on agreement between pathologists on selected histologic features. Using 2 point as opposed to 4-point grading scale increased agreement between pathologists (maximum kappa = 0.69 using 4-point scale versus maximum kappa = 1.0 using 2-point scale). Significant association (P = .019- .04; 95% OR = 3.14-10.84) between lacteal dilation and hypoalbuminemia was found by 3 pathologists. CONCLUSIONS AND CLINICAL IMPORTANCE: Substantial inconsistency between pathologists remains despite use of pictorial template because of differences in slide processing. Distinguishing between mild and moderate lesions might be important source of the disagreement among pathologists.

Large hydatidiform mole: an unusual finding in a calving cow.

CASE HISTORY: A 4-year-old Friesian cow was reported to be having difficulty calving. Palpation by farm staff identified a large mass in the uterus, but no calf. CLINICAL FINDINGS: Veterinary examination per vaginam identified a small calf and a large immobile mass. The calf was delivered by Caesarean section, but the mass could not be extracted during surgery. Biopsying the mass resulted in the loss of a large amount of fluid from it, but it remained immovable; overnight, the mass was expelled per vaginam. Gross and histological examination of the mass showed it to comprise multiple oedematous chorionic villi, prominent stratified trophoblast, undifferentiated sub-trophoblastic mesenchymal tissue that contained adipose tissue, blood vessels and bizarre striated muscle fibres, as well as irregular cisterns in the centre. No recognisable embryonic or fetal tissue was found. DIAGNOSIS: Based on the gross and histological appearance it was concluded the mass was a complete hydatidiform mole. CLINICAL RELEVANCE: This is a rare, poorly understood condition of cattle. This is believed to be the first report in a cow in New Zealand.

Effect of sample quality on the sensitivity of endoscopic biopsy for detecting gastric and duodenal lesions in dogs and cats.

BACKGROUND: The quality of histopathology slides of endoscopic biopsies from different laboratories varies, but the effect of biopsy quality on outcome is unknown. HYPOTHESIS: The ability to demonstrate a histologic lesion in the stomach or duodenum of a dog or cat is affected by the quality of endoscopic biopsy samples submitted. More endoscopic samples are needed to find a lesion in poor-quality tissue specimens. ANIMALS: Tissues from 99 dogs and 51 cats were examined as clinical cases at 8 veterinary institutions or practices in 5 countries. METHODS: Histopathology slides from sequential cases that underwent endoscopic biopsy were submitted by participating institutions. Quality of the histologic section of tissue (inadequate, marginal, adequate), type of lesion (lymphangiectasia, crypt lesion, villus blunting, cellular infiltrate), and severity of lesion (normal, mild, moderate, severe) were determined. Sensitivity of different quality tissue samples for finding different lesions was determined. RESULTS: Fewer samples were required from dogs for diagnosis as the quality of the sample improved from inadequate to marginal to adequate. Duodenal lesions in cats displayed the same trend except for moderate duodenal infiltrates for which quality of tissue sample made no difference. Gastric lesions in dogs and mild gastric lesions in cats had the same trend, whereas the number of tissue samples needed to diagnose moderately severe gastric lesions in cats was not affected by the quality of tissue sample. CONCLUSIONS AND CLINICAL IMPORTANCE: The quality of endoscopically obtained tissue samples has a profound effect on their sensitivity for identifying certain lesions, and there are differences between biopsies of canine and feline tissues.

Acute B-cell lymphoblastic leukaemia in a 5-month-old boar.

CASE HISTORY: A 5-month-old mixed-breed boar presented with lethargy, weakness and anorexia of 1 week's duration. CLINICAL FINDINGS AND DIAGNOSIS: The boar had an elevated heart rate, slow capillary refill time and cyanotic skin over the ears; it was also severely anaemic. A necropsy revealed scattered petechial haemorrhages, small subcapsular white nodules on the kidneys, a nodule in the parenchyma of one testis, creamy-white bone marrow, a preputial diverticulum, and an ulcer of the pars oesophagea of the stomach. Cytology of peripheral blood and bone marrow identified large numbers of lymphoblasts, which were demonstrated using immunocytochemistry to be of B-cell origin. Histological examination of multiple organs also showed lymphoblastic infiltration. DIAGNOSIS: B-cell lymphoblastic leukaemia with secondary infiltration of lymphoid organs, kidneys, testis and preputial skin. CLINICAL RELEVANCE: This is the fi rst known reported case of acute B-cell lymphoblastic leukaemia in swine.

Spirometra erinacei / S. erinaceieuropaei in a feral cat in Manawatu with chronic intermittent diarrhoea.

CASE HISTORY: A feral cat captured in the Manawatu region of New Zealand was treated for worms and fleas, and kept confined in a metabolic cage. It showed good appetite and weight gain but had intermittent watery, yellow diarrhoea. CLINICAL FINDINGS: Clinical examination under sedation was unremarkable and routine blood tests showed no significant abnormalities. The cat was negative for feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Different canned cat foods did not alter the course of the diarrhoea, and the cat was euthanised 6 months after capture. At necropsy, two sections of adult Spirometra tapeworms were found in the jejunum and typical Spirometra eggs were found in colonic contents. Molecular identification of the parasite was undertaken, using the cytochrome-c oxidase subunit-1 gene (cox1) sequence. DIAGNOSIS: Chronic intermittent diarrhoea associated with Spirometra erinacei / S. erinaceieuropaei infection. CLINICAL RELEVANCE: Spirometra has not been reported in New Zealand before but has been associated with gastrointestinal disease in cats in other parts of the world. It requires species targeted treatment to be eliminated effectively, and is zoonotic. Diagnosis could be difficult for clinicians who are not familiar with the parasite and its life cycle.

Splenic haemangiosarcoma with metastasis to the cervical musculature in an aged pony.

CASE HISTORY: An aged pony gelding presented with sudden onset of neck pain, depression and ataxia and weakness of the hindlegs, together with longer-term weight loss. Diagnostic procedures failed to isolate the cause of these signs and, despite symptomatic treatment, the animal's condition deteriorated until it required euthanasia. NECROPSY FINDINGS: Post mortem examination revealed the presence of multiple splenic and hepatic haemangiosarcomata, with metastases to the lung and dorsal cervical muscles overlying C1 and C2 vertebrae. No lesions were present in the spinal cord, spinal column or brain. CONCLUSIONS: The weight loss and neck pain were explicable in terms of the sites and extent of the tumours, although it was unclear how the severe ataxia could have been produced by such lesions.

Food sensitivity in cats with chronic idiopathic gastrointestinal problems.

The objectives of this study were to investigate the prevalence of food sensitivity in cats with chronic idiopathic gastrointestinal problems, to identify the food ingredients responsible, and to characterize the clinical features. Seventy cats that presented for chronic gastrointestinal signs underwent diagnostic investigation. Fifty-five cats had idiopathic problems and were entered into the study. Diagnosis of food sensitivity was made by dietary elimination-challenge studies by using commercial selected-protein diets as the elimination diet. Sixteen (29%) of the 55 cats with chronic idiopathic gastrointestinal problems were diagnosed as food sensitive. The clinical signs of another 11 cats (20%) resolved on the elimination diet but did not recur after challenge with their previous diet. The foods or food ingredients responsible for the clinical signs were dietary staples. Fifty percent of affected cats were sensitive to more than 1 food ingredient. The clinical feature most suggestive of food sensitivity was concurrent occurrence of gastrointestinal and dermatological signs. Weight loss occurred in 11 of the affected cats, and large-bowel diarrhea was more common than small-bowel diarrhea. Assay of serum antigen-specific immunoglobulin E (IgE) had limited value as a screening test, and gastroscopic food sensitivity testing was not helpful. In conclusion, adverse reactions to dietary staples were common in this population of cats, and they responded well to selected-protein diets. Diagnosis requires dietary elimination-challenge trials and cannot be made on the basis of clinical signs, routine clinicopathological data, serum antigen-specific IgE assay, gastroscopic food sensitivity testing, or gastrointestinal biopsy.

Suspected zinc-induced copper deficiency in growing kittens exposed to galvanised iron.

AIM: To investigate the possible causes of fading coat colour and an acquired hind-limb ataxia affecting sixteen 4 to 5-month old kittens in a closed feline colony during 1993 and 1994. METHODS: Records of kittens and litters born in the colony between 1991 and 1997 were analysed. The kittens had been kept from birth until approximately 5 months of age in plastic cages with galvanised iron bar doors. Histopathological sections from 4 of the worst affected ataxic kittens necropsied in 1993 were re-examined. In addition, 6 of the original 16 affected kittens that survived were re-examined as 4 to 5-year old adults, which were moderately ataxic; these cats were then humanely killed for necropsy. RESULTS: In the kittens, clinical signs included lordosis, dysmetria, ataxia of the hind-limbs and fading coat colour; histopathological lesions included Wallerian-type degeneration in the spinal cord, pons and medulla, and neuronal degeneration in the vestibular nuclei and ventral horns of the spinal cord. Analysis of colony data ruled out an inherited disease, and there was no evidence of dietary inadequacy or excess. Similar, though milder, clinical and histopathological changes were noted in the affected adults. CONCLUSIONS: Circumstantial evidence is consistent with a diagnosis of zinc-induced copper deficiency caused by the ingestion of zinc oxide from the galvanised iron bar doors. CLINICAL RELEVANCE: Because of the possibility of zinc-induced copper deficiency, galvanised iron should be avoided when designing and constructing cages for cats in veterinary clinics, pet shops and boarding facilities.

Gastric Ollulanus tricuspis infection identified in captive cheetahs (Acinonyx jubatus) with chronic vomiting.

Gastritis, vomition and weight loss are common in captive cheetahs (Acinonyx jubatus). Gastric spiral bacteria (Helicobacter spp.) and the very small, viviparous nematode Ollulanus tricuspis, a stomach worm of cats, are believed to be important causes. Three sibling cheetahs at Wellington Zoo, New Zealand, developed chronic vomiting, diarrhoea and debility. Their parents were both South African-born. Response to antibacterial treatment was poor. Endoscopic examinations revealed chronic lymphoplasmacytic gastritis and Ollulanus infection. Treatment with oxfendazole and pyrantel embonate resulted in clinical improvement; however, 1 cheetah, which died 7 months later as a result of a ruptured liver due to hepatic amyloidosis, still had Ollulanus worms present in her stomach. Ollulanus tricuspis is a significant cause of gastritis and vomiting in captive cheetahs, lions and tigers, as well as wild cougars and tigers. The parasite has not yet been found in sub-Saharan Africa. Because of the unusual characteristics of this parasite, the literature on its life history and techniques for diagnosis is reviewed.

Black grain eumycetoma (Madurella mycetomatis) in the abdominal cavity of a dog.

A uterine stump granuloma was surgically removed from a sterilized bitch. Histopathology and fungal culture revealed Madurella mycetomatis eumycetoma. Infection may have occurred through a cesarean wound dehiscence. Long-term fluconazole therapy was instituted but failed to arrest and eliminate the infection.

Solitary cervical intra- and extramedullary schwannoma.

A case of solitary cervical intramedullary schwannoma with an extramedullary extension is reported. This case demonstrates the difficulty of radiologic diagnosis of these tumours and the necessity for pre-treatment biopsy.

Fatal disseminated cryptococcosis and concurrent ehrlichiosis in a dog.

Laboratory findings in an adult bull terrier presented with a history of anorexia and weight loss included the following: severe anaemia, leukocytosis, neutrophilia, lymphopaenia, thrombocytopaenia, Ehrlichia canis morulae in monocytes, hypergammaglo-bulinaemia, a bleeding tendency, icterus and proteinuria. In addition, a high Haemobartonella canis parasitaemia, non-encapsulated yeasts on urinalysis and a localised Demodex canis infestation were present. Treatment for ehrlichiosis was initiated but the dog died. Lesions found were a severe cryptococcal granulomatous pneumonia and cryptococcal colonies in the lungs, bronchial lymph nodes, kidneys, liver, spleen, heart, meninges, eyes and thoracic cavity. In addition, hyphal forms resembling Filobasidiella neoformans, the teleomorph of Cryptococcus neoformans, were seen in lung fine needle aspiration smears, impression smears and lung sections. C. neoformans was cultured from urine, lung and liver. Lung and kidney also yielded Salmonella typhimureum. Cortical atrophy with T-cell depletion of lymph nodes as well as splenic lymphoid follicular atrophy, typical of chronic ehrlichiosis-induced cell mediated immunosuppression, could have predisposed to the fatal disseminated cryptococcis.