design: Intact salivary glands (SG) from partially fed Amblyomma americanum adult females feeding on rabbits were collected at different stages during the blood feeding and stored in RNAlater solution. Ticks were grouped by weight, the average weight of the group 3 is 24.7 mg. RNA extraction was performed with the AllPrep DNA/RNA/Protein Mini Kit (QIAGEN) according to manufacturer`s specifications.