Taste preferences in the cotton rat (Sigmodon hispidus)

Area of Science:

• Animal Behavior
• Sensory Science
• Mammalian Physiology

Background:

• Rodent taste preferences provide insights into sensory biology and ecological adaptations.
• Comparative data on rodent gustatory perception, particularly for sugars and salts, is often incomplete or contradictory.

Purpose of the Study:

• To investigate the taste preferences of hispid cotton rats (Sigmodon hispidus) for various sugar, salt, and acid solutions.
• To determine optimal concentrations for sugar and salt preferences in this rodent species.
• To explore potential sex-based differences in taste perception.

Main Methods:

• Utilized two-bottle, 48-hour drinking tests to measure fluid intake.
• Assessed preferences across five sugar types (fructose, glucose, sucrose, maltose, lactose) at varying concentrations (0.005-1.0 M).
• Evaluated preferences for three salt types (KCl, MgSO4, NaCl) and two acids across a range of concentrations (0.005-1.0 M for salts, 1.5-4.0 pH for acids).

Main Results:

• Significant concentration-dependent differences in intake were observed for all tested sugars, salts, and acids.
• All sugars were maximally preferred at a concentration of 0.10 M.
• Sodium chloride (NaCl) and potassium chloride (KCl) showed peak preference at 0.005 M, while magnesium sulfate (MgSO4) was maximally preferred at 0.05 M.
• Sex differences in intake were noted for sucrose and NaCl at several concentrations.

Conclusions:

• Hispid cotton rats exhibit specific concentration-dependent preferences for sugars and salts.
• The identified preferred concentrations for sugars and salts may serve as incentive values or reinforcers in future behavioral studies.
• Understanding these gustatory preferences contributes to the broader knowledge of rodent sensory biology and behavior.