Serum complement activity and serum enzymes in rats after a subcutaneous injection of toxin prepared from Pasteurella multocida type D

Toxin produced by Pasteurella multocida type D was investigated for its effect on serum complement and serum biochemistry in rats. Rats were given a sublethal single subcutaneous injection of D toxin equivalent to 0.2 microgram/kg of body weight. Serum obtained 1, 3, 5 and 7 days post-treatment was tested for complement activity, total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). Serum complement titers were significantly elevated (P less than 0.05) at all times after injection of toxin compared to rats injected with diluent and tested at the same intervals. Bilirubin was decreased but both control and D toxin-treated rats had low concentrations of bilirubin in their sera. The other biochemical constituents measured had no consistent pattern that would indicate liver damage in the rats.     

Exposure of rabbits to spores of Aspergillus fumigatus or Penicillium sp: survival of fungi and microscopic changes in the respiratory and gastrointestinal tracts.

Rabbits were exposed to spores of Aspergillus fumigatus by 1 of 2 routes: exposure to aerosols of dry spores or introduction of liquid suspensions of spores directly into the stomach. Rabbits also were exposed to aerosols containing spores of a Penicillium sp. Cultural and microscopic examinations of tissues from the respiratory and gastrointestinal tracts indicated fungi were distributed throughout the gastrointestinal tract of the rabbits within 1 hour after exposure to aerosols of A fumigatus or Penicillum spores. Viable A fumigatus and Penicillium were detected in lung tissues of rabbits for 2 or 3 weeks after inhalation of spores. Aspergillus fumigatus was isolated from the gastrointestinal tract no more than 1 week after aerosol exposure, and Penicillium, not beyond 48 hours. However, when large numbers of A fumigatus spores were introduced directly into the stomach, fungi were isolated from tissues for as long as 16 days after exposure even though the intestinal contents were negative 4 to 7 days after introduction of spores. Tests for precipitating antibody were negative, with one exception, among 26 rabbits surviving for 2 weeks or more. Microscopic changes were more pronounced in rabbits exposed to spores of A fumigatus than in rabbits exposed to Penicillium spores.