Five-month oral (diet) toxicity/infectivity study of Bacillus thuringiensis insecticides in sheep.

Bacillus thuringiensis insecticides (Bt) [Dipel (test substance D or Thuricide-HP (test substance T)] were administered in the diet for 5 months to castrated mixed rambouillet/merino sheep (24-34 kg at the beginning of the study) at a dose of 500 mg/kg/day (approximately 10(12) spores per day). No treatment-related effect was seen on weight gain or clinical chemistry parameters nor were significant gross clinical changes observed. Several blood and tissue samples taken just prior to the time the animals were killed or at necropsy were found to be positive for Bt when cultured. Detailed gross and microscopic pathologic examination of the sheep revealed several incidental lesions. However, the only lesion that may have been associated with the treatment was lymphocytic hyperplasia in Peyer's patches seen in the cecum of three sheep and it was not considered to be clinically significant.

Experimental production of arachnoiditis with glove powder contamination during myelography.

Adhesive spinal arachnoiditis is a rare condition of several causes, including complications of myelography. An experiment was conducted to study the effects of surgical glove powder contamination in the cerebrospinal fluid. The subarachnoid space of 45 rabbits was injected with either a suspension of powder from sterile surgical gloves, Pantopaque (iophendylate), or a combination of the two agents. Mild to severe arachnoiditis was produced in 10 of 17 animals injected with the combination of powder and Pantopaque. Only two of 16 rabbits injected with glove powder and one of nine with Pantopaque had more than minimal changes of arachnoiditis. Three rabbits (two injected with glove powder alone and one with both agents) died of meningitis within 1 week of injection. The combination of glove powder and Pantopaque is synergistic in producing arachnoiditis. These results emphasize the importance of meticulous technique in myelography.