Close relationship between equine and human molluscum contagiosum virus demonstrated by in situ hybridisation.

To determine whether the virus responsible for human molluscum contagiosum (MCV) is the causal agent of a similar disease in horses, in situ hybridisations using cloned fragments of human MCV DNA labelled with digoxigenin were carried out on formalin-fixed biopsy sections of lesions from two horses with molluscum contagiosum-like skin lesions. In both instances there was evidence of specific hybridisation of the labelled probe to target DNA in the sections under high stringency conditions, identified by the development of a deep blue-purple stain in the cytoplasm of cells in the stratum spinosum and stratum granulosum of the lesions and the absence of non-specific hybridisation in adjacent non-lesional areas of the epidermis. These results indicate that on the basis of very close homology of their viral DNA sequences, the causative virus of equine molluscum contagiosum is either identical with, or very closely related to, its human equivalent.

The prevalence of intestinal Salmonella infection in horses submitted for necropsy.

Specimens from the ileum, colon and rectum were aseptically collected from 50 consecutive horse carcases submitted for necropsy to the Department of Pathology, Faculty of Veterinary Science, University of Pretoria. These were bacteriologically examined for the presence of Salmonella. Seventeen of these were positive for Salmonella at one or more sites. Serotyping of the isolates revealed a dominance of Salmonella Hayindogo in these horses.

Cardiomyopathy in ostriches (Struthio camelus) due to avocado (Persea americana var. guatemalensis) intoxication.

Nine out of 120 ostriches died from congestive heart failure within 96 h of ingesting avocado leaves and immature fruit in an avocado orchard containing Hass and Fuerte cultivars. Foliage and immature fruit from both cultivars dosed to ostriches (n = 4) and domestic hens (n = 8) resulted in severe cardiomyopathy in all the ostriches. In the hens, which had received a lower dose, milder lesions occurred. Macroscopically the intoxication in ostriches resulted in a severe anasarca of the neck and ventral body. The cardiomyopathy was characterised by degeneration and necrosis of myocytes, a marked infiltration of heterophils and in one case, early fibroplasia.

[Suspected inherited granulocytopathy in four Holstein Friesian calves]. / Verdagte oorerflike granulositopatie in vier Holstein frieskalwers.

Five Holstein Friesian calves varying in age from 7 to 9 weeks old, were suspected of suffering from an inherited granulocytopathy known as bovine leucocyte adhesion deficiency (BLAD). Four of them were examined clinically and at necropsy. The most significant clinical findings were fever, depression, weakness, emaciation, diarrhoea, pseudomembranous gingivitis, loose teeth, respiratory infection and occult blood in the faeces. Significant clinicopathological findings were marked leucocytosis, mainly due to a neutrophilia, hypoalbuminemia, hypogammaglobulinemia, increased alpha- and beta-globulins, elevated alkaline phosphatase enzyme activity, hypoglycaemia, and decreased blood urea concentrations. The necropsy revealed emaciated carcasses, granulomatous to necrotising gingivitis, pseudomembranous to necrotising enteritis with perforations, bronchopneumonia, splenic atrophy, and hypoplasia of the thymus. Histopathological examination supported the macroscopic findings.

Generalised Listeria monocytogenes infection in a dog.

A 6-year-old Doberman bitch was presented for an acute onset of circling, hemiparesis and depression. Clinical examination revealed conjunctivitis, abdominal pain, anaemia, decreased facial sensation, decreased jaw, tongue and pharyngeal tone, decreased conscious proprioception, decreased flexor withdrawal reflexes, and abnormal hemiwalking and hemistanding. Pancytopaenia was evident on haematological evaluation. Bone marrow cytology revealed a bacterial infection. Cerebrospinal fluid analysis was normal. Despite antibiotic treatment, the dog died. On autopsy, widespread multifocal inflammatory lesions were found to be present in the lungs, liver, spleen, meninges, lymph nodes, adrenal glands and kidneys. Listeria monocytogenes was isolated in pure culture from these organs and tissues. Histopathological examination showed numerous gram-positive intracellular rod-shaped bacteria seen in all the above-mentioned organs.

Renal dysplasia in two adult horses: clinical and pathological aspects.

Renal dysplasia is reported in two adult horses in chronic renal failure. Renal dysplasia, complicated by severe interstitial pyelonephritis, was diagnosed on renal biopsy and confirmed on post mortem examination.

Suspected avocado (Persea americana) poisoning in goats.

A herd of 15 Cameroon goats was suspected of having been poisoned by eating leaves of the Fuerte variety of avocado pear (Persea americana). Two of the affected goats were examined clinically, while necropsies were carried out on 3 of the 4 that had died. The most significant clinical findings were tachycardia, hyperpnoea and evidence of lung oedema. At necropsy severe lung oedema, hydrothorax and hydropericardium were present. Severe myocardial degeneration, necrosis and fibrosis were the major histopathological findings.

Encephalitozoon infection in a still-born foal.

A stud Clydesdale foal was still-born near full term. Macroscopic examination revealed a normal placenta, pulmonary atelectasis and faint white mottling of the kidneys. Microscopically there was severe lymphoplasmacytic interstitial nephritis. Numerous organisms resembling Encephalitozoon cuniculi were present in the affected kidneys. The organisms occurred in the areas of inflammation as well as in the renal glomeruli and intracellular cysts in the renal tubular epithelial cells and exhibited Gram positive staining. Ultrastructurally the organisms possessed a polar vacuole and a spiral filament typical of Microsporidia. The organisms were not detected in sections of the other organs examined.

Molluscum contagiosum in a horse.

An adult stallion presented with a severe papular dermatitis of especially the neck, chest and genitalia. A marked scrotal oedema was present. Histopathological examination of skin biopsies, revealed the presence of numerous intracytoplasmic molluscum bodies in areas of focal epidermal hyperplasia. Electron microscopical examination showed the presence of typical pox virions in affected epidermal cells. Attempts at viral isolation were unsuccessful. This is believed to be the first reported case of molluscum contagiosum in a horse in the Republic of South Africa.

Systemic cryptococcosis in a cat.

A three-year-old, castrated, male, domestic cat presented with an antibiotic-resistant rhinitis, generalised lymphadenopathy, and skin nodules distributed over the neck, thorax and abdomen. Cryptococcus neoformans was identified on cytology and histopathology specimens, and cultured from all the specimens submitted. The cat died without antimicrobial therapy being instituted. Systemic cryptococcosis was confirmed on necropsy. Lesions were found in the upper and lower respiratory tracts, skin, subcutis, skeletal musculature, lymph nodes, kidney, eye and brain. This report details a case of systemic cryptococcosis in a cat and gives a review of feline cryptococcosis.

Bronchiolo-alveolar adenocarcinoma in a horse.

A bronchiolo-alveolar adenocarcinoma was diagnosed in the lungs of a horse which was euthanased after protracted respiratory disease and radiological evidence of pulmonary neoplasia. Multifocal, large, firm neoplasms occurred throughout both lungs. Neoplastic lesions were not found elsewhere. Histologically the bronchiolar and alveolar architecture was retained. The cuboidal cells lining neoplastic alveoli had very vacuolated cytoplasm, while some were ciliated. Electron microscopy identified the cells as Type II pneumocytes. Numerous distended myelinoid bodies in the tumour cells accounted for the vacuolated appearance seen by light microscopy. Special stains for fat, mucin, mucopolysaccharides and glycogen failed to elucidate the nature of the substance in these vacuoles.

Nutritional secondary hyperparathyroidism in a lion cub.

A female lion cub about 5 months old from a litter raised artificially in a lion park, was euthanased and necropsied. The history was one of poor growth, lameness, a reluctance to move and skeletal malformations with disproportionately large head and feet. The cub had been fed meat and milk supplemented with calcium and vitamins. All the bones in the body were exceptionally soft and flexible. The long bones, vertebrae and ribs were easily split in half with a knife. The scapulae were deformed and medially curved. The long bones were shorter and thicker in diameter than normal, with very thin cortices. Numerous pathological fractures exhibiting minimal callus formation were present. The ribs were rounded, abnormally curved and very short in comparison to the length of costal cartilages. Radiographically, a marked osteoporosis was observed. Histopathological examination revealed a severe diffuse fibrous osteodystrophy with very little bone present. The osteoid was improperly mineralised and tissue sections for microscopy were cut without any need for prior decalcification. Little space for haemopoietic tissue remained. The lesions were considered consistent with those in animals raised on a diet containing excessive phosphates and low calcium.

Parasitic pneumonia in a dog caused by a lung fluke of the genus Paragonimus.

Post mortem examination of a dog that died after a spell of respiratory distress revealed about 20 randomly distributed cystic lesions in the lungs. Those examined each harboured 2 light-brownish conical flukes approximately 10 mm in length. Histopathological examination of such a lesion revealed the presence of Paragonimus (lung fluke) embedded in it. The parasite had a typical spiny integument as well as other characteristics typical for the genus. Typical pigmented operculated eggs were embedded in the surrounding tissues. The life cycle of the parasite is briefly discussed.

Pathology of canine lentiginosis profusa.

Lentiginosis profusa was diagnosed in 3 pedigree Pugs namely two unrelated parents and their female offspring. Macroscopically the lentigines appeared as black macules up to 10 mm in diameter and occurred especially in the skin of the ventral parts of the body. Skin biopsies revealed localised acanthosis and hyperkeratosis with prominent rete ridges and epidermal hyperpigmentation in the absence of any other significant dermal pathology.

Bacterial myocarditis secondary to parvovirus enteritis in a puppy.

A purulent bacterial myocarditis, secondary to parvovirus enteritis was diagnosed in a 3-month-old St Bernard puppy. The clinical course was of 2 days duration and was characterized by pyrexia, severe vomition, haemorrhagic diarrhoea and dehydration. Post mortem examination revealed a haemorrhagic enteritis and multifocal purulent myocarditis. Histopathological examination proved that the latter was of bacterial origin. It is postulated that this resulted from a bacteraemia secondary to the intestinal lesions caused by parvovirus infection.

Concomitant feline infectious peritonitis and toxoplasmosis in a cheetah (Acinonyx jubatus).

Three wild caught littermate cheetahs succumbed to feline infectious peritonitis (FIP) after being in captivity for approximately 9 weeks. A necropsy and histopathological examination on one revealed typical signs of FIP as well as histopathological lesions in the liver and brain of concomitant toxoplasmosis. Hypochromic anaemia, neutrophilia, lymphopaenia, eosinopaenia and elevations of alpha 2-globulin and gamma-globulin fractions of the blood were present in the one animal examined. These findings together with some clinical signs are reported.

Inanition in a Derby eland due to foreign body abomasitis.

An adult Derby eland bull, Taurotragus derbianus (Grey) kept in captivity showed wasting over a period of 3 months. It died from acute inhalation pneumonia while being transported in an immobilized state. Post mortem examination revealed a chronic ulcerative abomasitis. Histopathologically it was established that the abomasitis resulted from penetration of the mucosa by awns of plant material.

Adenovirus pneumonia in a puppy.

A case of adenovirus pneumonia in a puppy is described. The emphasis is on histopathology where an alveolitis with typical Cowdry type A intranuclear inclusions in macrophages, pneumocytes and bronchiolar epithelial cells were the most significant findings. The literature on the subject is briefly reviewed.