The partial replacement of full-fat soyabean meal in diets for early-weaned pigs with algae or sunflower oil cake meal. Three starter diets for early-weaned pigs, (weaned at an age of 21 days) were fed ad libitum for 26 days to 72 piglets. The control diet contained only full-fat soyabean meal as the basic protein source. Sunflower oilcake meal and drum-dried algae were included at a 10% level in the other two diets. The diets were formulated to contain 18% protein, 1,1% lysine and 14,5 MJ DE/kg on an air-dry basis. The growth and feed utilization of the piglets fed the algae-containing diet was highly significantly less efficient than that of piglets fed the sunflower oilcake containing diet.