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

8GUIdE FOR ThE CARE ANd USE OF LAbORATORy ANIMALStemperature. The physical environment of the secondary enclosure, such asa room, constitutes the macroenironment.Water QualityThe composition of the water (water quality) is essential to aquatic animalwell-being, although other factors that affect terrestrial microenvironmentsare also relevant. Water quality parameters and life support systemsfor aquatic animals will vary with the species, life stage, the total biomasssupported, and the animals’ intended use (Blaustein et al. 1999; Fisher2000; Gresens 2004; Overstreet et al. 2000; Schultz and Dawson 2003).The success and adequacy of the system depend on its ability to match thelaboratory habitat to the natural history of the species (Godfrey and Sanders2004; Green 2002; Lawrence 2007; Spence et al. 2008).Characteristics of the water that may affect its appropriateness includetemperature, pH, alkalinity, nitrogen waste products (ammonia, nitrite,and nitrate), phosphorus, chlorine/bromine, oxidation-reduction potential,conductivity/salinity, hardness (osmolality/dissolved minerals), dissolvedoxygen, total gas pressure, ion and metal content, and the establishedmicrobial ecology of the tank. Water quality parameters can directly affectanimal well-being; different classes, species, and ages in a species may havedifferent water quality needs and sensitivities to changes in water qualityparameters.Routine measurement of various water characteristics (water qualitytesting) is essential for stable husbandry. Standards for acceptable waterquality, appropriate parameters to test, and testing frequency should beidentified at the institutional level and/or in individual animal use protocolsdepending on the size of the aquatic program. Staff managing aquatic systemsneed to be trained in biologically relevant aspects of water chemistry,how water quality parameters may affect animal health and well-being,how to monitor water quality results, and how water quality may affect lifesupport system function (e.g., biologic filtration).The specific parameters and frequency of testing vary widely (dependingon the species, life stage, system, and other factors), from continuousmonitoring to infrequent spot checks. Recently established systems and/orpopulations, or changes in husbandry procedures, may require more frequentassessment as the system ecology stabilizes; stable environments mayrequire less frequent testing. Toxins from system components, particularlyin newly constructed systems, may require special consideration such asleaching of chemicals from construction materials, concrete, joint compounds,and sealants (DeTolla et al. 1995; Nickum et al. 2004). Chlorineand chloramines used to disinfect water for human consumption or todisinfect equipment are toxic to fish and amphibians and must be removed