not account for faculty time spent on IACUC activities. In addition to the costs of faculty time on the IACUC, there are the known costs of administrative staff to support the IACUC functions and the unknown costs of faculty time spent in completing protocols. A National Institutes of Health study of regulatory burden (NIH 1999) cited six major categories of regulatory issues: redundancy of program and facility inspections; different annual reports required by the Office of Laboratory Animal Welfare (OLAW), the US Department of Agriculture (USDA), and the Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC); USDA requirements that do not allow for professional judgment; significant differences between OLAW and USDA requirements; inconsistent interpretation of regulations and policies by oversight groups; and complexity of regulations governing the import and movement of nonhuman primates. NIH did not estimate the cost of those issues, but addressing them should result in savings of time and money.

Of institutions that replied to the 1999 ARS, 48 reported costs of supporting the IACUC of $0-$301,000. Larger institutions (group 3) spent more on IACUC support, had programs for monitoring use of animals in research in addition to semiannual inspections, and had more faculty and staff serving on IACUCs; but the cost of compliance as a percentage of research dollars received was generally higher for small programs. The proposal to require USDA to regulate use of rats, mice, and birds in research will probably increase the regulatory burden, particularly for smaller institutions.

Many factors will contribute to increased mouse use over the next few years: the genome project and functional genomics, interinstitutional transfer of various mouse lines, conditional and tissue-specific mutations, chemical and viral mutagenesis, creation of therapeutic models, and in vivo gene-transfer experiments. In light of those factors, many institutions are projecting at least a threefold increase over 5 years. Other species—such as rat, rabbit, pig, and nonhuman primate—might become models in gene transfer experiments. In addition, growth in the use of aquatic species—including Xenopus frogs, zebrafish, and other fishes—is likely. Such projected increases require construction or renovation of new space, a portion of which must be flexible to accommodate nonrodent species.