Classen, H., Cho, M., Hucl, P., Gomis, S. and Patterson, C. A. 2014. Performance, health and tissue weights of broiler chickens fed graded levels of hairless hulled yellow and brown canary seed (Phalaris canariensis L.). Can. J. Anim. Sci. 94: 669-678. Research examined the effects of dietary levels (0, 15, 30 and 45%) of hulled yellow (C05041) and brown (CDC Maria) canary seed on the performance and health of broiler chickens. Eight (six birds each) and five (four birds each) replications per treatment were used from 0 to 21 and from 22 to 35 d of age, respectively. Growth rate and feed intake were affected in a quadratic manner by canary seed level from 0 to 21 d with the highest growth achieved by 15 and 30% treatments, but were not affected from 22 to 35 d. Feed to gain ratio decreased linearly with increasing canary seed for both 0- to 21-d and 22- to 35-d time periods. Mortality was not affected by level of canary seed, but more birds fed the C05041 cultivar died as a result of yolk sac infection and infectious causes than did birds fed CDC Maria. Level of canary seed affected jejunum, kidney and bursa of Fabricius proportional weights in a quadratic manner with no differences between the 0 and 45% treatments. No interactions were found between dietary level and cultivar of canary seed. Treatment did not affect gross necropsy at trial end or histopathology of key organs. Yellow and brown hairless canary seed has merit and is safe for poultry feeding.