Effect of shipping stress on clincopathologic indicators in F344/N rats.

A variety of hematologic, serum chemistry, and cytochrome P450 variables from 20 F344/N rats were measured and analyzed statistically to determine the effects of shipping stress on clinicopathologic indicators. Additionally, whole body, liver, and total kidney weights were recorded and compared. Ten rats were assayed upon receipt (stressed group), and 10 additional rats were held on a wire substrate for 12 days (poststress group) and assayed. Significant differences were detected between the 2 groups in ratio of total kidney weight to body weight, segmented neutrophil count, monocyte count, eosinophil count, and serum cholesterol, serum potassium, serum aspartate transaminase, and serum lactate dehydrogenase values.

Evaluation of the control of Myobia musculi infestations on laboratory mice with permethrin.

The efficacy of permethrin against Myobia musculi (Schrank) (Acari:Myobiidae) infestations on mice was evaluated using four different dose delivery methods. In all methods, an attempt was made to deliver 0.5 mg of active permethrin weekly to each mouse. Successful control was achieved with topical or environmental treatment with 0.25% permethrin dust and by dipping the mice into a 0.6 g/l permethrin emulsion. The use of an emulsion applied to the bedding produced the least satisfactory control. Untreated mice had an average infestation rate of 57.3% throughout the study. No significant differences were seen between treated and untreated groups in either body weight or histopathology of the liver, lung, or kidney.