These drugs as usually formulated so that they can be administered orally (in drench, tablet or in feed form), by injection or percutaneously (as a pour on). In cattle production intraruminal delivary systems or '''rumen boluses''' have been developed. They are capabel of delivering the anthelmintic for periods of over 90 days. There are two types of delivery system. The '''sustained release''' boluses work via a diffusion gradient, osmotic pump or mechanical device and emit the anthelmintic at a constant rate. The '''pulse release''' boluses emit therapeutic doses every three weeks. Oxfenbendazole is currently the only drug that has been formulated in this way. | These drugs as usually formulated so that they can be administered orally (in drench, tablet or in feed form), by injection or percutaneously (as a pour on). In cattle production intraruminal delivary systems or '''rumen boluses''' have been developed. They are capabel of delivering the anthelmintic for periods of over 90 days. There are two types of delivery system. The '''sustained release''' boluses work via a diffusion gradient, osmotic pump or mechanical device and emit the anthelmintic at a constant rate. The '''pulse release''' boluses emit therapeutic doses every three weeks. Oxfenbendazole is currently the only drug that has been formulated in this way. |