To Cindy Sooy: >Is there any danger or side effects associated with Ivermectin use in >breeding ferrets? There are not supposed to be any side effects with the use of ivermectin at recommended dosages in young or pregnant animals. > 1) At what age should you start kits on Ivermectin? Probably around 16 weeks, the same time as they receive their last shots. > 2) Dr. Williams mentioned a dosage of 30mcg/lb once a month, does Ivermectin >come in a standard concentration? No, ivemectin is usually purchased as an injectable preparation for worming horses, at, I believe, 100 mcg/ml. Most vets dilute it out and put it in brown bottles (sunlight can denature it nd cause it to be ineffective.) > 3) Should all my ferrets be tested before I put them on medication? Is the >test the same as for a dog? Adult ferrets should receive an OCCULT heartworm test. Dogs are usually tested by passing blood through a small filter and examining the filter under the microscope fo the presence of larval heartworms, which ciruclate in the peripheral blood. With ferrets, the presence of these wroms is unusual (due to the low numbers of heartworms carried by infected ferrets) so this test is ineffective. However, we can use an occult heartworm test on blood samples from ferrets which tests for small proteins shed by the worms. Young ferrets less than four months do not require testing, as the worms have not had time to establish themselves as adults in the heart, and are still susceptible to the effects of the ivermectin. Bruce H. Williams, DVM Dept. of Veterinary Pathology Chief Pathologist, AccuPath Armed Forces Institute of Pathology [log in to unmask] Washington, D.C. 20306-6000 [log in to unmask] [Posted in FML issue 1222]