title: Influence of test duration on the sensitivity of the two-bottle choice test.
abstract: The long-term two-bottle choice test is commonly used as a simple screen to examine the acceptance of taste solutions by rodents. As part of an investigation of factors influencing the sensitivity of the two-bottle choice test, we determined the extent to which test duration influenced test sensitivity. C57BL6/J and 129X1/SvJ mice received four series of eight two-bottle tests, with each test lasting 1, 2, 4 or 6 days. Each series involved sequential tests with water, 2 mM saccharin, 5 and 50 mM citric acid, 30 and 300 micro M quinine hydrochloride, 75 mM NaCl and 10% ethanol. There were significant differences between the strains in intake of saccharin, 5 and 50 mM citric acid, NaCl and ethanol in 4 and 6 day tests, but only saccharin and ethanol in 2 day tests, and 5 mM citric acid and ethanol in 1 day tests. To compare the sensitivity of the tests, we developed an analytical approach based on the comparison of deviations of individual 129X1/SvJ mice from the C57BL6/J strain mean. Our results suggest that to discriminate between strains or treatments when using 'standard' laboratory conditions and methods, 1 day tests are generally inadequate and 2 day tests are useful only if large effects are anticipated. Tests lasting 4 or 6 days are more sensitive, but conducting 6 day tests provides little additional benefit and sometimes is detrimental relative to conducting 4 day tests.
authors.affiliation: Monell Chemical Senses Center, 3500 Market St., Philadelphia, PA 19104, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Tordoff
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Bachmanov
mesh_terms: D000818:Animals; D002755:Choice Behavior; D019343:Citric Acid; D000431:Ethanol; D005518:Food Preferences / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D011803:Quinine; D012439:Saccharin; D012965:Sodium Chloride; D013045:Species Specificity; D013649:Taste / Q000502:physiology*; D013997:Time Factors; D014867:Water
chemical_list: D014867:Water; D019343:Citric Acid; D000431:Ethanol; D012965:Sodium Chloride; D011803:Quinine; D012439:Saccharin