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Thirty-five experiments are demonstrated in which high-lactating cows were exposed to abrupt changes from a normal dietary Mg supply to an extremely Mg-poor diet. The preliminary diet was adequate, supplying the cows with about 25 g Mg per day. The experimental feeding was individually calculated, containing 2.55 Mg for maintenance and 0.15 g for each kg of milk. Daily serum mineral analyses showed a pronounced hypomagnesaemia in all 35 experiments within 2 to 18 days. In 5 experiments there was a simultaneous fall in serum Ga, and the cows collapsed in tetany. The other 30 cases remained clinically healthy in spite of the low serum Mg level as long as the diet was given unchanged. In 25 cases these already hypomagnesaemic cows were exposed to a relatively high oral supplementation of Na(2)HPO(4),Na(2)SO(4) or both. In 9 cases the supply led to pronounced tetanic convulsions, in 4 cases a subtetanic state was observed, and in 4 cases the cows showed borderline symptoms, i.e., they reacted clinically as well as analytically immediately after the supply was given, but no attacks appeared, and the cows recovered as soon as normal fodder was given. In 8 cases the cows did not react to the “trigger” doses at all. The experiments are discussed and the reactions compared with those observed when high-lactating cows are let out on tetany-prone, (NH(4))(2)SO(4)-dressed pastures. The conclusion is drawn that a high Mg content in the diet prior to a Mg-deficient diet has little, if any, influence on the tendency to precipitate tetany. Considerable decreases in content, or availability, of dietary Mg always lead to decreases in serum Mg. Occasionally, under special unfavourable circumstances, when the drop in serum Mg is extraordinary rapid, the serum Ca level may drop as well and tetany occur without further stressing elements. In most cases, however, the results seem to support the suggestion that tetanic couvulsions are not conditioned entirely by the reduced availability of Mg but are to a great extent dependent upon the serum Ca-reducing effect of co-operating, so-called trigger compounds, simultaneously present in the diet. In this connection the addition of Na(2)HPO(4) and Na(2)SO(4) to the Mg-poor diet has been studied and found to confirm the suggestion made in earlier papers (Ender et al 1957; Dishington 1965) that the high content of Na, K, P, and S found in (NH(4))(2)SO(4)-dressed pasture grass seems to play a prominent part in making this grass tetany-prone.

Suckling mice are serviceable in many virological experiments because they are sensitive to various virus species. Simpson & Groupé (2) succeeded in adapting the Beaudette strain of infectious bronchitis virus (IBV) to suckling mice, using the intracerebral route of inoculation. A study of the properties of a Finnish strain of infectious bronchitis virus (IBV(F)) has been published recently (1). It successfully established the intracerebral adaptation of IBV(F) to suckling mice. The suckling mice were 100 % sensitive to this virus strain up to an age of 12 days. Symptoms of the central nervous system with a typical clearly discernible gibbosity in the vertebral column were elicited after an incubation period of 2—3 days, and the animals died 3—4 days after the inoculation. Parallelly with IBV(F), transmission experiments with other IBV strains were carried out. The present paper is a report on the results of these experiments.

Background At least 3% of children spend some of their childhood in public care and, as a group, have poor outcomes across a range of education, employment, health and social care outcomes. Research, using social care or government datasets, has identified a number of risk factors associated with children entering public care but the utility of risk factors in clinical practice is not established. This paper uses routine primary health care data to see if risk factors for children entering public care can be identified in clinical practice. Methods A nested case control methodology using routine primary care data from the United Kingdom. Health service use data were extracted for the 12 months before the case child entered public care and compared with 12 months of data for four control mother child pairs per case pair, matched on the age and sex of the child and the general practice. Exposures of interest were developed from a systematic review of the literature on risk factors associated with children entering public care. Results Conditional logistic regression was used to investigate the combined effect of more than one exposure of interest. Maternal mental illness (OR 2.51, 95% CI 1.55-4.05), maternal age at birth of the child, socio-economic status (5th quintile vs. 1st quintile OR 7.14, 95% CI 2.92-17.4), maternal drug use (OR 28.8, 95% CI 2.29-363), non attendance at appointments (OR 2.42, 95% CI 1.42-4.14), child mental illness (OR 2.65, 95% CI 1.42-4.96) and child admission to hospital (OR 3.31, 95% CI 1.21-9.02) were all significantly associated with children entering public care. Maternal use of primary care contraception services was negatively associated with children entering public care (OR 0.52, 95% CI 0.31-0.87). Conclusions Differences in health service use can be identified from routine primary care data in mother child pairs where children enter public care after controlling for maternal age and socio-economic status. The interaction between different risk factors needs testing in a cumulative risk model using longitudinal datasets.

In n previous report dealing with the pathology of bovine fascio-liasis the author described an unknown cell type in the epithelium of bile ducts. The histological and histochemical investigations published in this paper suggest that the cell may be considered a globule leukocyte. Globule leukocytes are rare in uninfected livers but are occurring in abundance in main bile ducts of cattle with spontaneous fascioliasis and also in small perilobular ducts in dicrocoeliasis. Liver fluke infection causes an increase in the population of subepithelial mast cells. Mast cell and globule leukocyte present similarities In their cytochemical properties. However, at low pH toluldinc blue shows a stronger but Alcian blue a weaker affinity for mast cells than for globule leukocytes.