This invention provides for, inter alia, oral homogeneous veterinary pastes for the treating, controlling and preventing of endo- and ectoparasite infections in warm-blooded animals or birds, such as horses and household pets. This invention further provides for a process of preparing these veterinary pastes and for a method for increasing the bioavailability of the anthelmintic agent contained in the paste in the warm-blooded animal or bird. The inventive oral homogeneous anthelmintic pastes comprise a first anthelmintic agent, for example, prazequantel and/or pyrantel, and at least one marcrolide anthelmintic compound, a solvent, which dissolves both the first anthelmintic agent and second the macrolide anthelmintic compound, and a thickening agent. The inventive oral homogeneous pastes achieve a better bioavailability of the two active anthelmintic agents than when the two actives are in suspension and not dissolved