W. R. Kelly

Effects of the intravenous administration of Clostridium perfringens type D epsilon toxin on young goats and lambs.

Young goats (n = 18) and lambs (n = 10) were compared in respect of the effects of Clostridium perfringens type D epsilon toxin. Toxin produced neurological signs within 0.5-3 h of intravenous injection in (1) all of six kids given doses of 250, 185 or 120 mouse lethal doses 50% (MLD50)/kg body weight, (2) two of the three kids given 60 MLD50/kg, and (3) all of five lambs given 250 or 120 MLD50/kg. Six kids and three lambs given 45, 30 or 15 MLD50/kg, one lamb given 60 MLD50/kg, and three kids and one lamb given saline (controls) all remained clinically normal. Gross post-mortem changes were observed only in the kids and lambs that showed clinical signs. In the kids these changes consisted of severe acute interstitial and alveolar oedema of the lungs. However, only two out of five lambs that presented clinical signs showed pulmonary oedema. No histological changes were observed in the brain of any of the kids inoculated with epsilon toxin. In the brain of four out of the five lambs given doses of 120 or 250 MLD50/kg, there were histological lesions consisting of perivascular proteinaceous oedema and haemorrhages. These results show that kids and lambs are equally susceptible to the intravenous injection of epsilon toxin, but that they differ in the histological response of the central nervous system to the toxin.

Spontaneous lymphoid neoplasia in the koala (Phascolarctos cinereus)

Thirteen cases of lymphoid neoplasia were examined in koalas from New South Wales and Queensland. Haematological and biochemical data were collected from 2 cases while all were subjected to detailed necropsies. Affected koalas were adults of both sexes and the disease had a variable time course. The 2 koalas examined haematologically were leukaemic. On a morphological basis, 5 cases were classified as multicentric, 7 cases as abdominal (but not necessarily with alimentary tract involvement) and one case as solitary. In most cases, the neoplastic cells appeared to be either lymphoblasts or prolymphocytes.

Skin cancer and papillomaviruses in cattle

We examined proliferative lesions on the sun-exposed, unpigmented skin of 13 cattle. Ages of animals at first examination ranged from 4 to 15 years, and 4 were observed for from one to 3 years, during which time progression to malignancy occurred in 2 of them. Early lesions consisted of keratin scales and horns; histology showed underlying acanthosis and hyperkeratosis. Advanced lesions were either squamous cell carcinomas or basaloid tumours with sebaceous and/or squamous differentiation; some were locally invasive but no metastases were found in the 6 animals that were available for necropsy. All 3 types of lesion could occur on the same animal. In early lesions from 11 of 12 animals, there was evidence for the presence of papillomavirus, either virions or viral DNA, the latter detected by gel electrophoresis and/or molecular hybridization. Viral DNA was also detected in 3 basaloid tumours and 2 squamous cell carcinomas from 4 animals. The DNA bound to a probe of bovine papillomavirus type 1 DNA under conditions of low stringency. We suggest that both infection with papillomavirus and exposure to sunlight, possibly in conjunction with other factors such as a period of photosensitization, are involved in the production of this spectrum of proliferative lesions, which bear some resemblance to human skin cancer.

Mortierella wolfii isolated from the liver of a cow in Australia

Genetic basis of epilepsy in the Bernese mountain dog THE pedigrees of4005 Bernese mountain dogs were analysed; they included five subpopulations containing 50 epileptic dogs from 13 generations. Thirty-one of these dogs were male, and 49 of them suffered generalised seizures of the grand-mal type with a well defined prodromal and postictal phase. Thirty-one of the affected dogs had had their first seizures at between one and three years of age, and the age at first seizure was significantly lower in the dogs with affected parents than in those with healthy parents. There was no correlation between the inbreeding coefficient and either the age at first seizure or the rate of incidence of the seizures. The results of the pedigree analyses and a binomial test support the hypothesis that idiopathic epilepsy in the Bernese mountain dog has a polygenic, recessive mode of inheritance. KATHMANN, I., JAGGY, A., BUSATO, A., BARTSCHI, M. & GAILLARD, C. (1999) Journal ofSmall Animal Practice 40, 319 Ultrasonography of the normal stifle of cattle BY using 7-5 MHz linear or convex and 5 MHz sector transducers, the homogeneously echogenic patellar and collateral ligaments, the combined tendon of the long digital extensor and peroneus tertius muscle, the popliteus tendon, the anechoic articular cartilage of the femoral trochlea, the echogenic menisci and the hyperechoic bone surfaces of the stifle region of 18 healthy cattle were imaged successfully. The boundaries of the joint pouches became partially identifiable only when there were small amounts of anechoic fluid in the medial and lateral femorotibial joint pouches. The paper provides reference data for ultrasonographic studies of stifle disorders in cattle. KOFLER, J. (1999) Veterinary Journal 158, 21 The Veterinary Record, August 28, 1999 261