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Fifteen pregnant, bovine virus diarrhoea-mucosal disease (BVD-MD) antibody-free Jersey heifers were infected experimentally with a mixture of 10 cytopathic strains of BVD-MD virus isolated from cattle in Britain. Each cow was inoculated intramuscularly on gestation day 100 with a high or a low dose of virus grown in primary calf testis tissue cultures. None of the cows showed clinical signs of illness following exposure, but all had seroconverted within six weeks. Six fetuses, including one set of twins, died in utero following infection. Of these five were aborted between days 136 and 154; the sixth one was mummified and still retained at day 300. The remaining 10 fetuses survived to term, but all showed evidence of intrauterine growth retardation with or without gross malformation and/or dysmyelination of the central nervous system. Three were clinically affected with congenital nervous disease. Of the 10 liveborn fetuses, two had specific serum antibodies to BVD-MD. Non-cytopathic BVD-MD virus was recovered from all of the remaining eight. When non-immune cows become infected with BVD-MD virus in mid gestation: transplacental infection of the fetus will probably result; apart from the risk of fetal death, with or without abortion, there is a high probability of fetal mal-development which may not always be clinically obvious; the immunological competence of the fetus may be impaired; congenital infection is likely in a substantial proportion of liveborn calves. About one in 16 bovine fetuses in British herds are estimated to be at risk from BVD-MD virus infection.

A survey of seventeen cases of pancreatic disease seen in cats over a 2 year period is presented. Three were suffering from diabetes mellitus, eleven from pancreatitis, and three had neoplastic lesions. The main clinical findings and post‐mortem details are recorded. The occurrence of chronic and sub‐acute pancreatitis appears more common than reported hitherto.

Abstract.A 4-year-old Canadian holstein bull developed the spastic syndrome, an episodic but progressive disorder causing pelvic limb muscular spasms. A post-mortem study, including morphometry of skeletal muscles and teased peripheral nerve fibers of the pelvic limb, revealed mild type I1 skeletal muscle fiber atrophy and minimal, focal segmental demyelination with remyelination, and axonal degeneration in peripheral nerves. Such alterations are probably incidental or age-associated. Idiopathic muscular cramps is the most probable explanation of the clinical disease and is consistent with the absence of significant morphologic pathologic lesions. Materials and MethodsA Canadian holstein bull, originally imported in 1980 from Canada for artificial insemination use in the United Kingdom, began to show clinical signs when almost 4 years of age. A detailed clinical examination was done when the bull was 4 years 7 months of age, and daily visual inspections were continued until the bull was killed for necropsy 2 months later. Live weight immediately before death was 1,080 kg.The bull was killed by exsanguination following the simultaneous intravenous injection of xylazine (Bayer : Rompun) and etorphine hydrochloride/acepromazine maleate (C-Vet : Large Animal Immobilon). Upon necropsy, peripheral nerves and skeletal muscles identified were sampled from the left side of the carcass (Fig. 1). The brain and spinal cord, with attached complete spinal nerve roots of the left side at segments C7, L4-6, and S,, were fixed in phosphate-buffered, neutral, 10% formalin (BF). Other major organs and selected skeletal tissues were also sampled into BF.Lengths of identified peripheral nerves were dissected and suspended under tension in 2.5% glutaraldehyde in 0.1 M Sorensen's buffer at pH 7.4 and 4 C for 2 hours. Lengths were cut into 1.5 cm segments, and large diameter nerve segments were further subdivided along perineurial planes. Subsequent treatments were to provide isolated single nerve fibers, 1 pm plastic (araldite-embedded), and 5 pm or 10 pm paraffin wax sections.Nerve segments for plastic embedding and teased fiber preparations were removed from 2.5% glutaraldehyde after a further 1-2 hours and stored overnight in 0.1 M Sorensen's buffer. Nerve for teasing was post-fixed in Dalton's fluid" for 2 hours and for storing in araldite resin at -20 c.After thawing, isolated nerve fibers were prepared. l4 Fibers were progressively and unselectively teased by a single operator using straight No. 1 intestinal suture needles. Fifty to 70 individual fibers with at least three consecutive internodes were qualitatively assessed from each nerve. Measurements of internodal length and fiber diameter were made and the results expressed statistically and graphically. l6 Trimmed segments of Nn. femoralis, gluteus cranialis, and tibialis were post-fixed in 1% osmium tetroxide in 0.1 M Sorensen's buffer, routinely dehydrated, and embedded in araldite. Transverse and longitudinal sections were cut at 1 pm and stained with toluidine blue.Bl...

The clinical and pathological features of two lactating ewes with 'kangaroo gait', a locomotory disorder, are described, along with brief details of two further archival cases. Clinical neuropathological signs were consistent with a bilateral radial paresis and pathologically there was a polyneuropathy with preferential severe involvement of radial nerves. Flock incidence of the condition is low and previous experience suggests the clinical disorder is not progressive, recovery occurring at the end of lactation. The cause is unknown.