Zinc oxide is the metal zinc that has been oxidized. The chemical formula is ZnO, 1 zinc atom and 1 oxygen atom held together by an ionic bond. Zinc oxide does occur in nature as the mineral zincite, but it is quite rare and commercially unavailable.
I have done a few stool samples in my time and have always just stored them in the fridge, until the next day to take them into the docs. Good luck hun I hope they get it sorted.
In otherwise healthy people, symptoms should go away in 2 to 5 days, but they may last for 1 to 2 weeks. People who have been treated for salmonella may continue to shed the bacteria in their stool for months to a year after the infection.