Comparison of three methods of thiamine supplementation by measurement of urinary thiamine excretion in sheep.

The relative efficacy of thiamine supplementation to sheep by injection, subcutaneous implant and orally administered protected thiamine bolus was compared in two experiments using a grass and hay ration and a ration containing bracken rhizomes to induce thiamine deficiency. In both experiments, urinary excretion of thiamine was significantly higher in supplemented sheep than in the controls, and in sheep supplemented by injection than in sheep supplemented by implant or protected boluses. Thiamine excretion was lower in sheep fed the ration containing bracken rhizomes than in sheep fed the grass ration.

A fodder mycotoxicosis of ruminants caused by contamination of a distillery by-product with Aspergillus clavatus.

Cattle and sheep, grazed successively on the same pasture and given the same supplementary feeding, developed ataxia and several animals became recumbent. Three cattle died within two weeks and the worst affected sheep were killed for laboratory examination. The supplementary diet which consisted largely of a distillery by-product, malt culms, was submitted for mycological examination and fed to two housed lambs. Aspergillus clavatus was cultured from the culms, and both the affected sheep and the housed lambs showed cerebrospinal degenerative changes. The clinical signs and neuropathology were closely similar to a mycotoxicosis, attributed to A clavatus, which is seen infrequently in cattle in France, Bulgaria, South Africa and China.

Papovavirus-like infection in budgerigars (Melopsittacus undulatus).

Outbreaks of a disease in two budgerigar aviaries caused 20% and 53% mortality respectively in recently hatched chicks during the 1985 breeding season. Clinical signs were first observed at 5 to 7 days of age. In most birds darkening of the normal skin colour was followed by death in 2 to 10 days. In individual nests all or part of a hatch could be affected. Occasional survivors had abnormal plumage. Few gross lesions were found at post-mortem examination. Histologically, many large basophilic intranuclear inclusions were present in multifocal degenerative lesions throughout the epidermis, kidney, heart, brain and other tissues. These inclusions were shown by transmission electron microscopy to contain numerous virus particles which, on direct examination, had a .diameter of 46 to 56 nm and a papovavirus-like morphology. These outbreaks were considered to be cases of budgerigar fledgling disease, a syndrome that has been reported in other countries but not previously described in Great Britain.

A farm investigation into swayback in a herd of goats and the result of administration of copper needles.

Clinical, biochemical and pathological findings led to a diagnosis of swayback in a herd of goats. Trace element values in soil, pasture and supplementary feed were measured, and copper oxide needles administered to the adult goats. This form of treatment had a more limited effect in these goats than is reported in sheep.

Prevalence of herpesvirus infection in British red deer and investigations of further disease outbreaks.

A serological survey of the prevalence of a new herpesvirus isolated from red deer (Cervus elaphus), tentatively designated herpesvirus of Cervidae type 1 (HVC-1), has shown that the virus is widespread in free-living and farmed red deer. Neutralising antibodies were detected in hill deer culled at three different locations in the north of Scotland, in farmed deer on five of eight Scottish farms and in four of 12 groups of English farmed or park deer. Fifty-eight of 145 (40 per cent) hill deer, 67 of 203 (33 per cent) Scottish farmed deer and 26 of 172 (14 per cent) English deer had antibody, the overall prevalence being 29 per cent. Further outbreaks of ocular disease in farmed red deer calves caused by HVC-1 were investigated. Deer sent to an auction from one farm were found after sale to have been incubating the disease and it was thus spread to seven deer farms. Despite a high incidence of clinical disease in the calves from the original farm, few in-contact deer showed clinical signs.

Salmonella montevideo infection in sheep and cattle in Scotland, 1970-81.

Outbreaks of abortion associated with infection by Salmonella montevideo have affected sheep in the east, especially the south-east, of Scotland each year since 1972. Disease in the north and north-east was usually less severe. Between 1 January 1970 and 31 December 1981, a total of 67 incidents affecting sheep were reported by veterinary laboratories to the Communicable Diseases (Scotland) Unit, 87% of which presented during the main lambing months of February, March and April. Twenty-one episodes of bovine infection were also recorded over the same period, 17 of which involved single animals only, usually an aborted cow or a scouring calf. Despite intensive investigations, neither the origin nor the mode of spread of S. montevideo infection among sheep and cattle in Scotland have been established with any certainty, although there has been considerable evidence indicating the role of scavenging wild birds, particularly seagulls, as vectors transmitting infection to other farms in the same district. Also largely unexplained are the differences in the epidemiology and clinical pattern of disease in the south-east compared to the north and north-east, while sheep in the west of Scotland have remained virtually unaffected throughout.