Five dogs used for Pavlovian experiments on gastric secretion in the Physiology Department, Imperial Institute of Experimental Medicine, St Petersburg in 1904. Ivan Petrovic Pavlov is best know for his work on conditioned reflexes, in which he conditioned dogs to salivate in anticipation of food by ringing a bell each meal time (Pavlovs dog). This discovery occurred whilst he investigated the link between salivation and digestion using dogs. This physiological research is what earned him a Nobel prize.