Clinical and pathological findings of Babesia infection in dogs

The clinical and pathological findings of Babesia infection in 32 dogs in northern Australia are presented. Eleven different breed types were represented from 6 localities in north Queensland and one locality in northern Western Australia. Twenty three (72%) were males. Babesia-infected dogs were grouped by the degree of haematological disturbance and clinical severity: Acute babesiosis (25/32), all pups with severe haemolytic anaemia; subclinical carriers (5/32) with non-specific malaise, characterised haematologically by a normal erythrogram but marked leucopenia; chronic anaemia, observed in 2 adult dogs. Pups were azotaemic (serum urea greater than 6.6 mmol/l) and had elevated serum bilirubin levels (20.8 to 48.5 mmol/l). Total serum protein was usually within the normal range. Pups that died were also hypoglycaemic and severely hyperkalaemic (K+ greater than 10 mmol/l). Low parasitaemias in routine blood smears complicated diagnosis but smears made from ear or toe capillaries, or after haematocrit concentration, greatly enhanced finding parasitised cells. At necropsy, pallor and jaundice were the most consistent observations. Haemoglobinuric nephrosis, an active reticulo-endothelial system and capillaries packed with large numbers of infected erythrocytes were the main histopathological findings. A combination of imidocarb dipropionate at 5 mg/kg body weight, given intramuscularly, with fluid therapy and blood transfusion was the most successful treatment.     

OPTIMAL INTERPOLATION AND ISARITHMIC MAPPING OF SOIL PROPERTIES III CHANGING DRIFT AND UNIVERSAL KRIGING

Universal kriging is a form of interpolation that takes account of local trends in data when minimizing the error associated with estimation. The presence of such trends, or drifts as they are known, is identified qualitatively, and their form found quantitatively by structural analysis, which simultaneously estimates semi-variances of the differences between the drift and actual data. The resulting semi-variograms are then used for the interpolation. The method was applied to measurements of electrical resistivity made in the soil at 1 m intervals at Bekesbourne, Kent. Analysis showed that the data could be adequately represented as a series of linear drifts over distances of 4 m to 8 m and with negligible nugget variance. Semi-variances of residuals from the drift were computed, and used to krige missing values and so complete an isarithmic map of the site. The method is by no means universally applicable in soil survey, mainly because of the large nugget variances usually encountered. These effectively prevent any distinction between constant and changing drift. They arise in part because measurements are made on small widely separated volumes of soil. Universal kriging is likely to be profitable only where measurements are made on contiguous volumes of soil or after substantial bulking.     

Intracellular study of recurrent facilitation

Recurrent facilitation in the cat's spinal cord has been studied in deep peroneal and quadriceps motoneurons with the use of intracellular recording. The presence of facilitation was indicated by several criteria, among them increased firing index of the cells or decreased latency of firing. In many, but not all, facilitated cells the conditioning volley caused a small visible depolarization. Subthreshold synaptic potentials were frequently increased in magnitude by the conditioning volley, which also increased the effectiveness of a stimulus applied through the microelectrode. Facilitation was found in a large percentage of the motoneurons investigated and was clearly able to bring about pronounced changes in the excitability and firing behavior of these cells.