Zenobi, M. G., Lardner, H. A., Jefferson, P. G. and McKinnon, J. J. 2014. Blended by-product feed pellets for backgrounding cattle. Can. J. Anim. Sci. 94: 533-543. Two trials were conducted to evaluate the performance of cattle fed blended by-product pellets (BP) formulated to be high in starch (HS 45% DM) or fat (HF 8.5% DM) and low (LSP; 27% of CP DM) or high (HSP; 37% of CP DM) in soluble protein. In trial 1, 300 crossbred steers (320±21.6 kg, mean±SD) were assigned to one of 25 pens and fed one of five diets. The control diet consisted of 46.9% forage and 53.1% barley-based concentrate. The four treatments were 48.5% forage and 51.5% BP (DM). Diets were formulated to 1.63 and 1.02 Mcal kg^-1 NEm and NEg, respectively (DM). In trial 2, 180 crossbred steers (326±20.3 kg) were assigned to one of 15 pens, each assigned to one of three treatments. The control was 54.3% forage and 45.7% concentrate, while the two HF BP treatments were 56.6% forage and 43.4% BP (DM). All diets were formulated to 1.57 and 0.97 Mcal kg^-1 NEm and NEg, respectively (DM). In trial 1, no (P=0.36) effect of treatment was observed on average daily gain (ADG); however, dry matter intake (DMI) was reduced (P<0.01) with the HS BP relative to the control and HF BP. Gain:feed (G:F) was poorest (P<0.01) for the HF BP. In Trial 2, no effect of treatment was observed on ADG (P=0.80) or DMI (P=0.06); however, cattle fed the control diet had the highest (P<0.01) G:F. Relative to the control, the calculated dietary NEg content (Mcal kg^-1 DM) was 8.0% lower (P<0.01) for the HF BP in Trial 1 and 6.7% lower (P<0.01) in Trial 2. No effect (P>0.05) of soluble crude protein was observed. The results indicate that BP can be a viable supplemental energy and protein source for growing cattle.