Guide for the Care and Use of Laboratory Animals - Office of ...

6GUIdE FOR ThE CARE ANd USE OF LAbORATORy ANIMALSdate of inoculations, history of surgical procedures and postoperative care,information on experimental use, and necropsy findings where applicable.Basic demographic information and clinical histories enhance the valueof individual animals for both breeding and research and should be readilyaccessible to investigators, veterinary staff, and animal care staff.breeding, Genetics, and Nomenclature Genetic characteristics are importantwith regard to the selection and management of animals for use inbreeding colonies and in biomedical research (see Appendix A). Pedigreeinformation allows appropriate selection of breeding pairs and of experimentalanimals that are unrelated or of known relatedness.Outbred animals are widely used in biomedical research. Foundingpopulations should be large enough to ensure the long-term genetic heterogeneityof breeding colonies. To facilitate direct comparison of researchdata derived from outbred animals, genetic management techniques shouldbe used to maintain genetic variability and equalize founder representations(Hartl 2000; Lacy 1989; Poiley 1960; Williams-Blangero 1991). Geneticvariability can be monitored with computer simulations, biochemical markers,DNA markers and sequencing, immunologic markers, or quantitativegenetic analyses of physiologic variables (MacCluer et al. 1986; Williams-Blangero 1993).Inbred strains of various species, especially rodents, have been developedto address specific research needs (Festing 1979; Gill 1980). Wheninbred animals or their F1 progeny are used, it is important to periodicallymonitor genetic authenticity (Festing 1982; Hedrich 1990); several methodsof monitoring have been developed that use immunologic, biochemical,and molecular techniques (Cramer 1983; Festing 2002; Groen 1977; Hoffmanet al. 1980; Russell et al. 1993). Appropriate management systems(Green 1981; Kempthorne 1957) should be designed to minimize geneticcontamination resulting from mutation and mismating.Genetically modified animals (GMAs) represent an increasingly largeproportion of animals used in research and require special considerationin their population management. Integrated or altered genes can interactwith species or strain-specific genes, other genetic manipulations, andenvironmental factors, in part as a function of site of integration, so eachGMA line can be considered a unique resource. Care should be taken topreserve such resources through standard genetic management procedures,including maintenance of detailed pedigree records and genetic monitoringto verify the presence and zygosity of transgenes and other geneticmodifications (Conner 2005). Cryopreservation of fertilized embryos, ova,ovaries, or spermatozoa should also be considered as a safeguard againstalterations in transgenes over time or accidental loss of GMA lines (Conner2002; Liu et al. 2009).