Cycloheximide(Naramycin®), which is commonly used as an agricultural fungicide, was dissolved in distilled water in a concentration of 0.1%. When mice taste the solution, they show abnormal behavior because of the unpleasant taste. They then refuse to drink the solution because of its specific odor.
In our experiment, we withheld water for 48 hrs, then offered two bottles of water, one distilled water only and the other 0.1% Cycloheximide. When the mouse chose the distilled water to drink, the response was rated as correct. When the Cycloheximide solution was chosen, an error was recorded. Ten mice were tested ten times during a 10-minute trial, and the percentages of correct responses were recorded.
1)In the first experiment, there were 79 correct responses in 92 trials(85.9%). In the second and third trial, all l00 responses were correct(100%).
2)One day after nasal irrigation with a 1% aqueous solution of zinc sulphate, the percentage of correct responses dropped significantly to 72.7% an indication of anosmia.
3)Seven days after zinc sulphate treatment, the percentage of correct responses started to increase gradually. Twenty days after treatment, it was 98.5%, indicating recovery of olfactory sensitivity.