In accordance with the guidelines of WAAVP, 10, 25, 28, three fecal samples were examined by microscopic examination after zinc sulfate centrifugation to determine the presence of Giardia cysts 3 days before administering the drugs, as well as the day that treatments were administered Day 0 and on days 5, 7, 9, 11, 14, 18, 25 1 1 100 cysts per slide; 2 100 300 cysts per slide; 3 300 500 cysts per slide; 4 TNTC too numerous to count per 10 objective field 30, 31 how to buy cialis