PURPOSE: To prepare a feed having high feeding ratio from rye, by adding salt water to rye, conditioning the mixture, mixing with acetic acid diluted with water, conditioning, preheating and steaming the mixture, pressing with a roll, cooling, and mixing with other feed materials.

CONSTITUTION: The stock tank 1, the selector 2, the first stirring mixer 5 furnished with the salt water tank 3 through the pump 4, the first conditioning tank 7 having a heating device 6 such as steam heater in the tank, the second stirring mixer 5' furnished with the acetic acid solution tank 8 through the pump 4', and the second conditioning tank 7' are arranged in series and connected with a conveyor. The tank 7' is connected with the preheating tank 9 and the steam ejector 11 connected with the hot steam generator 10, in series. The rolling mill 14 to press the raw material with the smooth roller 12 and the cogged roller 13 is connected with the steam ejector 11, and the cooling regulator 16 having a cooling fan 15 is connected with the rolling mill 14. Further, the intermediate storage tank 17, the mixer 18, the product tank 19, the packaging machine 20, etc. are connected therewith.