Use of a Molasses-based Liquid Feed Supplement to Deliver Ivermectin to Cattle to Control Ectoparasites

摘要

Two different dosages of ivermectin (25 ppm and 100ppm) were used to medicate a liquid molasses feed supplement for free-choice consumption by cattle. Calves that fed on supplement medicated at 25 ppm with ivermectin had a 14 day mean consumption of 0.62 ± 0.07 kg supplement/animal/day producing an average dose of 15.5 mg of ivermectin per calf The mean ivermectin level in serum for the 25 ppm rate was 15.7 ± 2.6 ppb for days 8 - 14 of the study, and the peak average ivermectin blood serum level was 20 ± 8.8 ppb on the fifteenth day, one day after the last day of treatment. Calves that fed on supplement medicated at 100 ppm ivermectin had a 14 day mean consumption of 0.63 ± 0.14 kg supplement/ animal/day, producing an average daily dose of 63 mgof ivermectin per calf The peak average ivermectin blood serum level for the 100 ppm rate was 85.6 ± 23.6 ppb on the tenth day of treatment; and for days 8-14 of the trial the mean ivermectin blood serum level was 76.7 ± 6.2 ppb. Seven days after termination of the study, no ivermectin was detected in the serum of cattle treated at the 25 ppm rate, while cattle treated at the 100 ppm rate still had ivermectin detectable at 14 ppb. Fourteen days after termination of treatment, no ivermectin was detected in the serum of cattle treated at the 100 ppm rate. An ivermectin blood serum level of > 10 ppb is known to control biting flies and ticks on cattle, suggesting that use of a molasses-based liquid feed supplement as a delivery method for systemicallyactive drugs could be beneficial to the USD A-APHIS-VS Cattle Fever Tick Eradication Program.on cattle, suggesting that use of a molasses-based liquid feed supplement as a delivery method for systemically active drugs could be beneficial to the USDA-APHIS-VS Cattle Fever Tick Eradication Program.