59Fe utilisation and excretion in anaemia of cattle caused by Pimelea trichostachya intoxication

Experimental chronic Pimelea poisoning, with severe anaemia, was produced in 4 calves by daily oral dose rates of Pimelea trichostachya of between 20 to 60 mg/kg body weight of whole plant. Bone marrow function was studied before and during intoxication using 59Fe to determine plasma iron clearance rates, intraerythrocytic iron incorporation rates and percentage iron uptake, and faecal blood loss was measured before and during intoxication. It was shown that bone marrow activity was neither significantly depressed nor enhanced during intoxication. There was however, evidence of a slight increase in erythrocyte maturation rate. Reticulocytosis was not observed during the development of anaemia, but did occur in 3 of the calves shortly before death.

The pathology and haematological changes in experimental Pimelea spp. poisoning in cattle ("St. George disease")

Six young cattle were intoxicated with either stem or extracts of stem of Pimelea trichostachya or P. continua. Oral dosage with whole plant or alcoholic extracts was shown to reproduce all the clinical and pathological features of the various field syndromes known collectively as "St. George disease". Subacute intoxication resulted from relatively high oral dose rates, of the order of 60 mg of whole stem/kg body weight/day, maintained for about 2 weeks. Diarrhoea, weakness and anaemia were the predominant features of this sundrome. Lower dose rates, regulated according to the severity of diarrhoea, eventually produced signs of circulatory failure (subcutaneous oedema, hydrothorax and cardiac dilatation) in addition to anaemia and diarrhoea. It did not prove easier to produce circulatory failure by intranasal insufflation of powdered plant. Although the bone marrow of most affected calves did not react to the anaemia there was some evidence that erythropoietic tissue was not directly damaged during the intoxication.

The fate of a toxigenic strain of Staphylococcus aureus in vacuum-packaged bacon

Pork was cured by (a) the Wiltshire method and (b) a hygienic sweet cure process. Representative samples of both bacons were inoculated at ;low' density (10(3) organisms/g.) and ;high' density (10(6) organisms/g.) with a toxin-producing strain of Staphylococcus aureus, ;High' and ;low' density samples of both bacons were each stored at 5 degrees C. for 42 days and 15 degrees C. for 21 days.Results indicated that the test organism at high inoculum density grew slowly in both bacons at 5 degrees C. The organism survived at 5 degrees C. in both ;low density' bacons. At 15 degrees C. the test organism grew; growth being more pronounced in the ;hygienic' than in Wiltshire bacon.