At the same time you buy your microscope be sure to get some slides and cover slips. Many online companies, including greatscopes.com sell kits that include an eyedropper which will come in handy. You can wash and reuse slides and cover slips many times if you are careful with them. Be sure to rinse with distilled water so they are sparkling clean.
You might enjoy purchasing a few prepared specimens that you can use to practice looking through your microscope. These specimens can also be educational for your youngsters.
You will need a small vial that holds about 12cc of liquid and is narrower than a cover slip for floating the fecal sample. Your veterinarian uses a special fecal vial for dog and cat samples and you can usually buy one from them. Be sure to tell them that you only want the vial, you are going to do your own exam, so they don't charge you for a full fecal test. You can clean and reuse them.
Finally it will help to have a good book that has clear photographs of parasite eggs so you can identify what you see in the microscope. Veterinary Parasitology by William J. Foreyt has good photos and covers life cycles and treatments for parasites found in most species of domestic animals.
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