PNNL

Abstract

Hematologic recovery, body weight, and behavior were assessed following serial blood collection in 10-14-week-old C57BL/6 mice. Male and female mice (5-11 mice for pilot groups, 23-35 mice for full study groups) had either 15%, 20%, or 25% total blood volume (TBV) collected once weekly for 6 weeks. The weights of all animals recovered or increased from one collection to the next with the exception of the 25% TBV male pilot group. The behavior of all animals appeared normal throughout the study with the exception of the 25% TBV male pilot group. Erythrogram value changes from baseline were analyzed at each weekly blood collection time point, and recovery was defined as the return of mean hemoglobin (Hgb) values to within 2 SD of mean baseline values. According to this definition, mice in the 15% TBV male group, and 15%, 20%, and 25% TBV female groups recovered. To support the statistical definition of recovery, comparisons were made to human anemia categories to assess the clinical relevance of the Hgb values. Based on these data, we conclude that female mice can have up to 25% TBV collected once weekly for six weeks and male mice can have up to 15% TBV collected once weekly for six weeks without producing weight loss, behavioral changes, or clinically significant anemia.