The effects of desalivation by duct ligation or salivary gland extirpation on taste preference in rats

Abstract

Albino rats were desalivated by either duct ligation or extirpation of the major salivary glands. The preference tests consisted of a choice between two cups containing a solid diet or between two bottles containing solutions. The flavour additives were quinine sulphate or NaCl. Rats normally have a slight preference for salt diets and show a clear aversion for bitter tastes. Short-term testing of the desalivated rats started 4 days after surgery and longterm testing at 104 days. Each test group consisted of 6–9 rats and the same number of controls. The proportion of flavoured food or fluid selected relative to total intake was analysed statistically. Both duct-ligated and gland-extirpated rats were hypogeusic to quinine- and NaCl-containing solutions. Neither the mode of desalivation nor the time factor played a role in the acceptance of the quinine- or NaCl-flavoured solutions. Presentation of the same taste stimuli in either a liquid or solid medium resulted in different taste response of the desalivated rats. The texture qualities of the diet were of greater importance in acceptance of food than taste per se.