Farmers perception about availability and utilization of Spirulina (Arthrospira fusiformis) were assessed and its nutritive value compared against reference proteins (soybean and nuge cake). Samples of Spirulina were collected from Arenguade and Chitu lakes of rift valley of Ethiopia. A survey was conducted on purposively selected 100 households (HH) living around the Lakes which are located in Gerbicha and Labu subuqa districts of Debre Zeit town and west Arsi zone, respectively. Chemical composition and in vitro dry matter digestibility (IVDMD) and total gas volume (TGV) of feed samples were determined. Respondents of both districts are not aware of Spirulina as animal feed. Spirulina was available during dry season in Arenguade and whole year in Chitu. The highest (p < 0.05) ash (26%), ether extract (EE, 13%), crude protein (CP, 33%) and IVDMD (96%) was recorded for Spirulina from Lake Arenguade. There was no significant difference (p > 0.05) in crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL) and metabolizable energy (ME) contents between Spirulina from both lakes. Spirulina from Chitu produced the highest TGV (31.2 ml) and fermented faster than Spirulina from Arenguade. Lowest (p < 0.05) ash, EE, CP and IVDMD and higher (p < 0.05) CF, NDF, ADF, ADL and TGV were recorded for reference proteins than Spirulina. ME content of Spirulina (3200 kcal/kg) was higher (p < 0.05) than that of nuge cake (3011 kcal/kg) but lower (p < 0.05) than that of soybean (3474 kcal/kg). Therefore, the chemical composition and IVDMD showed the potential of Spirulina to be used as a substitute of the reference feeds.