Strategies to reduce variation in Xenopus regeneration studies.

In this study, we present strategies for experimental design that minimize variation in Xenopus hindlimb regeneration results. We have standardized our laboratory culture conditions for older stage Xenopus tadpoles. We have established a normal tadpole growth curve for our laboratory and characterized normal tadpole behaviors in an effort to eliminate abnormal tadpoles from our experiments. We have used large sample sizes and statistical analysis to establish normal regeneration performances for seven amputation planes in stages 55-57 tadpole hindlimbs. We have demonstrated that regeneration performance of abnormal tadpoles is significantly different than that of normal tadpoles. We have examined the kinetics of ossification in developing Xenopus hindlimbs, and have found that increasing ossification rates and rates of regeneration decline are inversely correlated.