Development of an in vitro / in vivo correlation method to assess the efficiency of oral drug release from oral medications in swine - Phase 1b: Restoring drug release

Project 21-05 - Dr. Jerome del Castillo

Dr. Jerome del Castillo, University de Montreal 
Canadian pork producers use medicated feeds to combat disease and improve performance of swine herds. In the initial phase of our research project, we demonstrated that feedstuff-drug premix interactions significantly obstruct the in vitro release of dietary chlortetracycline and lincomycin. Relative to the pure drug premixes, the premix-fortified feedstuffs released between 80% and 40% of their drug content, depending on the water-holding capacity (WHC) of the tested feedstuffs. Noteworthy, ground corn and soybean meal created the greatest obstacle to the release of both dietary drugs. We hypothesize that this obstacle to drug release is additive when these feed-grade drug premixes are added to mixtures of feedstuffs, implying that we can increase their release by partly replacing the corn or soybean meal with alternative feedstuffs that increasingly are used in swine nutrition, or by using some feed additives that dissociate the drug-feedstuff complexes. By expanding the range of tested feedstuffs, we will verify the reliability of WHC as an indicator of the obstacle to the release of these dietary drugs. Hence, the WHC of feedstuffs should help refining the formulation of porcine medicated feeds to preserve the therapeutic efficacy of the dietary drugs for which the pork producers are paying.