A process for the manufacture of semi-plastic soft chewable veterinary pharmaceutical unit doses containing 4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalenecarboxamide (afoxolaner) using a rotary moulding machine to achieve uniform shape and active ingredient content, and the semi-plastic soft chewable veterinary pharmaceutical dosage units obtained by this process.