To begin, dissolve inhalable environmental pollutants in a 0.9%saline solution. Use a 5%zinc sulfate solution once as it has been shown to cause loss of smell. Using a pipetting gun, administer 10 microliters of the solution into one nostril of the mouse, allowing it to naturally inhale the solution into the nasal cavity.
Remove all chow pellets from the food hopper of the home cage, to carry out food deprivation, 18 to 24 hours before the test. Change the bedding materials for the mice. Take the cage containing the mice to the operating room to rest one hour before the start of the test.
Arrange the operating room during this period. Use transparent PVC standard mice cages marked as A and squirrel cages marked as B for testing. Mark the common cage used to place the mice after the experiment as cage C.Cover cages A and B with three centimeters of bedding material, and measure them with a ruler.
Then arrange the cages side by side, with 0.5 meters between each cage. Next, define the experimental area as a two-meter radius space centered on the cages, with the area beyond two meters designated as the observation area. Keep cage C and cages containing untested mice as far away from the experimental area as possible.
Now, select a position at random in cage B.Bury the food one centimeter below the surface of the bedding and smooth the surface of the bedding. Then place the mouse in cage A for four minutes. At the end of the time, transfer the mouse to cage B and turn on the video device before returning to the observation area.
Stop the video recording when the mouse picks up the food lock with its forepaw. Record the time from contact with the mat at the bottom of cage B until the food is found for each mouse. After the test, put the mouse in cage C and add feed and water.
In the food burial test, mice exposed to zinc sulfate were unable to find food for 240 seconds compared to the control group.