▁to ▁the ▁first ▁signs ▁of ▁disease ▁( pre pat ent ▁period ) ▁is ▁ 1 2 – 1 4 ▁days . ▁ ▁O oc yst s ▁can ▁be ▁observed ▁in ▁a ▁mic ros cope ▁as ▁a ▁colour less , ▁single - layer ed ▁wall ▁with ▁no ▁mic rop yle ▁with ▁a ▁size ▁of ▁ 1 5 – 2 2 ▁ µ m ▁x ▁ 1 3 – 1 8 ▁ µ m ▁and ▁having ▁a ▁subs pher ical , ▁sub ov oid ▁or ▁elli ptic ▁shape . ▁ ▁Di agn osis ▁The ▁in fection ▁status ▁of ▁an ▁animal ▁is ▁evaluated ▁by ▁exam ining ▁the ▁o oc yst s ▁using ▁different ▁fl ot ation ▁methods , ▁usually ▁by ▁counting ▁the ▁o oc yst s ▁under ▁a ▁light ▁mic ros cope ▁and ▁ident ifying ▁the ▁species ▁of ▁the ▁E imer ia ▁based ▁on ▁morph ology . ▁When ▁evalu ating ▁if ▁the ▁animal ▁is ▁having ▁e imer ios is , ▁due ▁to ▁in fection ▁with ▁E . ▁zu ern ii ▁( e imer ios is ) ▁or ▁other ▁path ogen ic ▁E imer ia ▁species , ▁four ▁things ▁are ▁taken ▁into ▁account : ▁age ▁of ▁the ▁animal , ▁presence ▁of ▁a ▁path ogen ic ▁E imer ia ▁species , ▁in fection ▁intensity ▁( o oc yst s ▁per ▁gram ▁fa ec es ), ▁and ▁presence ▁of ▁sympt oms ▁( di arr he a , ▁blood ▁in ▁the ▁fa ec es ). ▁ ▁Ep ide mi ology ▁Environment al ▁factors ▁can ▁influence ▁how ▁fast ▁new ▁o oc