Oral Group Medication in Pig Production: Characterising Medicated Feed and Drinking Water Systems

Despite common use of oral group medication in pig rearing, the homogeneity, stability and carry-over of frequently used medicinal products in feed and drinking water are largely unknown. Therefore, a field study was performed on 52 Belgian pig farms, characterising preparation and administration of medicinal products via these systems, and farmers' user experiences with medicated feed and medicated drinking water. The study showed that medicated drinking water is more commonly used than medicated feed, since 90.4 per cent of the farms sometimes use medicated drinking water and 69.2 per cent of the farms sometimes use medicated feed. The drinking water quality is evaluated at least once a year on only 30.7 per cent of the farms. Separate pipelines for medicated and non-medicated circuits were not present in any of the farms using medicated feed and in 27.7 per cent of the farms using medicated drinking water. With drinking water medication, 63.5 per cent of the farmers reported encountering practical problems, often related to solubility issues and precipitation of the active compounds. In contrast, medicated feed is bought ready-to-use from the feed manufacturer in 68.2 per cent of the cases, thus reducing the number of practical problems experienced by the farmer. This study shows room for improvement of oral group treatment, developing appropriate pharmaceutical formulations for drinking water medication, quality control of drinking water, using separate pipeline circuits, and cleaning and disinfecting protocols.