FTA cards are a good source of storing DNA molecule. yes you can extract DNA from them. this link would give you more insight. https://www.gelifesciences.com/gehcls_images/GELS/Related%20Content/Files/1392818611307/litdoc28982222_20140311044843.pdf
Thanke BAYODE. It was really useful protocol. I have tried using chelex but the PCR still did not work. I am not sure if the robustness of oocysts can permit for the matrix to disrupt it or not?