Acquired syringomyelia in a dog.

Acquired syringomyelia was diagnosed in an 11-year-old Fox Terrier with progressive paresis in the left pelvic limb. Myelography and magnetic resonance imaging confirmed an intramedullary lesion involving the left dorsolateral portion of the spinal cord at the level of L-2 and L-3 vertebrae. Clinical signs improved after surgical syringotomy. Microscopic evaluation of a biopsy specimen from the cyst wall did not establish a definitive histologic diagnosis. The cyst was decreased in size on magnetic resonance imaging 7 months later.     

Characterization of ovine strains of Mycobacterium paratuberculosis by restriction endonuclease analysis and DNA hybridization.

Restriction endonuclease analysis and DNA hybridization revealed five ovine strains of Mycobacterium paratuberculosis from South Africa had identical DNA patterns to an ovine strain from Canada. Genetically this strain type has features in common with the two major groups of M. paratuberculosis.     

Humoral recognition of lipopolysaccharide core antigens of gram-negative bacteria in neonatal swine

Serologic recognition of common lipopolysaccharide core antigens has been related to enhanced resistance to gram-negative bacterial disease in several species. Class-specific titers (IgG, IgM) were determined by direct ELISA, using intact Escherichia coli (J5) as a plate antigen. Serum samples were obtained from 224 neonatal swine between the ages of 36 and 60 hours. The mean (+/- SEM) log10 IgG titer against gram-negative core antigens was 1:1,713 +/- 0.4718 and the mean log10 IgM titer was 1:202 +/- 0.5644. The IgG titer was directly related with litter size, birth weight, and serum total IgG concentration; IgM titer was directly related with dam parity and serum total IgG concentration.     

Protection of chickens from Newcastle and Marek's diseases with a recombinant herpesvirus of turkeys vaccine expressing the Newcastle disease virus fusion protein.

Recombinant strains of herpesvirus of turkeys (HVT) were constructed that contain either the fusion protein gene or the hemagglutinin-neuraminidase gene of Newcastle disease virus (NDV) inserted into a nonessential gene of HVT. Expression of the NDV antigens was regulated from a strong promoter element derived from the Rous sarcoma virus long terminal repeat. Recombinant HVT strains were stable and fully infectious in cell culture and in chickens. Chickens receiving a single intra-abdominal inoculation at 1 day of age with recombinant HVT expressing the NDV fusion protein had an immunological response and were protected (> 90%) against lethal intramuscular challenge at 28 days of age with the neurotropic velogenic NDV strain Texas GB. Recombinant HVT expressing the NDV hemagglutinin-neuraminidase provided partial protection (47%) against the same challenge. Chickens vaccinated with recombinant HVT vaccines had low levels of protection against NDV replication in the trachea when challenged ocularly. Recombinant HVT vaccines and the parent HVT strain provided similar levels of protection to chickens challenged with the very virulent RB1B strain of Marek's disease virus, indicating that insertion of foreign sequences into the HVT genome did not compromise the ability of HVT to protect against Marek's disease.     

Pyrenophora japonica occurring on barley in South Africa

A Pyrenophora teleomorph was recently found on barley stubble in South Africa. Single-ascospore isolates, mated on water agar containing sterile pieces of barley stubble, produced the teleomorph within 12 months of incubation at 15°C in the dark. Based on morphological characteristics and symptom expression on barley plants, the teleomorph is ascribed to P. japonica (anamorph Drechslera tuberosa ). This is the first report describing the occurrence of the teleomorph of D. tuberosa in South Africa.     

Unilateral arytenoid lateralisation and extra-luminal polypropylene ring prostheses for correction of tracheal collapse in the dog

The surgical repair of tracheal collapse in 25 dogs is described. The initial presenting signs included coughing, dyspnoea, gagging, retching, exercise intolerance, cyanosis and collapse. Diagnosis was based upon the clinical signs, plain radiography and tracheal endoscopy. The collapse was corrected by the application of a number of extraluminal polypropylene prosthetic rings applied to the affected trachea. Additionally, a left arytenoid lateralisation was also performed. The perioperative complication rate was approximately 4 per cent, while the success rate was 75 per cent. The technique reduces the likelihood of catastrophic postoperative complications associated with iatrogenic laryngeal paralysis which is a possible complication of placement of extraluminal tracheal support devices.     

Neurological Manifestations of Niemann-Pick Disease Type C in Cats

Seven Domestic shorthair cats with a lysosomal storage disorder analogous to human Niemann-Pick disease type C, from a breeding colony were studied to characterize the neurological manifestations of this disorder. Affected cats were identified by means of liver biopsies at 4 to 6 weeks of age. Neurological examinations were performed at 2 week intervals from the onset of clinical signs. All cats displayed signs referrable to the cerebellum, with a subtle intention tremor noticed initially at 8 to 12 weeks of age; the disease was rapidly progressive. The tremor became more pronounced, menace response was lost, and severe dysmetria and ataxia developed. Three cats also had signs referrable to other areas of the central nervous system. Cats died or were euthanized between 12 and 43 weeks of age. Pathological findings included accumulation of substrate within neurons throughout the central nervous system, and axonal spheroid formation. The clinical and pathological findings in these cats are comparable to those in the human form of the disease.