The experiment was carried out for 28 days from August to September 2007 to investigate the efficacy of Ivermectin and Neem plants against ectoparasites in calves. Effect of Ivermectin and Neem plants on certain blood parameters hemoglobin (Hb), packed cell volume (PCV), total leukocyte count (TEC) and erythrocyte sedimentation rate (ESR) were studied in calves. A total of 15 calves were examined for the presence of ticks by physical examination and were divided into three equal groups as, Group A (infected control group), Group B (treated with Neem) and Group C (treated with Ivermectin). The therapeutic efficacy of Ivermectin was 100% against ectoparasites in calves on day 7, 14, 21 and 28 after the treatment of Ivermectin. Ivermectin and Neem showed significant effectiveness at 7th, 14th, 21st and 28th day of post treatment. The effects on TEC, Hb level was increased significantly at 7th, 14th and 28th day of treatment and PCV level was increased significantly on 28th day of treatment. On the other hand indigenous medicinal plant Neem leaves shown the efficacy of 68% at day 28 and body weight of Ivermectin and Neem treated calves also increased. All the calves after Ivermectin injection and Neem spray remained healthy, no adverse effect and calves appetite increased, growth and coat color improved rapidly.