| abstract |
A bolus for administration of a substance to an animal, the bolus including An external coating, and A core inside the external coating wherein the core is formed from a plurality of dosage media, wherein each dosage media contains a substance, the bolus characterised in that the dosage media are ordered within the bolus such that the amount of substance released by each dosage media is progressively more than the amount of substance released by the previous dosage media. |