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Applying analgesics to feed is a potentially easy method of providing pain-relief to sheep and lambs that undergo painful husbandry procedures. In order for sheep to consume medicated feed it needs to be know if the medication has an adverse odour or flavour that may affect consumption. It is also important to determine if therapeutic concentrations of a non-steroidal anti-inflammatories (NSAIDs) can be achieved when administered to sheep as a feed supplement. Pelleted feed was supplemented with flunixin (4.0mg/kg liveweight) and administered to eight sheep, which they were able to consume over a 12 h period. Blood samples were taken over 48 h and plasma drug concentrations were determined using Ultra High Pressure Liquid Chromatography. The mean time required to reach maximum concentration was 6 ± 1.46 h and ranged from 1 to 12 h. Average maximum plasma concentration was 1.78 ± 0.17µg/mL and ranged from 1.61 to 2.80 µg/mL. The average half-life of flunixin was 7.95 ± 0.77 h and there was a mean retention time of 13.62 ± 1.17 h. Sheep did not show aversiveness to pellets supplemented with flunixin. When consuming medicated feed ad libitum all sheep were able to obtain inferred therapeutic concentrations of flunixin in plasma within 6 h. Provision of flunixin in the feed may provide a practical way to provide pain relief to sheep and lambs following painful husbandry procedures removing the need for multiple injections, reducing handling stress and minimising labour requirements.