A treatment device 1, in particular to be swallowed by animals to treat intestinal parasites and worms, includes a plurality of discrete solid treatment devices 2, 3, 4, each in the form of a mini-bolus with a head 6 and a tail 7 shaped so that each mini-bolus can be partially nested together with adjacent boluses when the boluses are linked together by a flexible material 5 so that the treatment device forms a single articulated object that can be articulated in a plurality of different orientations. The boluses can be held together by a string passing through a hole through the body of each bolus or a tape along the sides of the boluses.
