Abstract
Two experiments evaluated feeding Brassica (B.) napus (canola) or B. juncea co-products to brown-shelled egg laying hens. In Exp. 1, diets including 20% B. napus or B. juncea extruded-expelled cakes (NC, JC) or solvent-extracted meals (NM, JM) compared to a control diet with no Brassica co-products, were fed to 120 hens (4 hens/cage, n = 6) for 36 wk. In Exp. 2, DM, gross energy, CP and amino acid (AA) retention/digestibility was determined by feeding diets containing 30% B. napus or B. juncea cakes or meals and basal diet to 240 hens (8 hens/pair of cages, n = 6) for 7 d. Cakes averaged 40 g/kg lower moisture, 28 g/kg lower CP, and 84 g/kg greater fat content compared with meals. In Exp. 1, there was no effect of diet on lay percentage or BW throughout the experiment. Feed consumption was 3.5 g/d lower in layers fed JM compared with controls and egg: feed was reduced by 14 mg egg/g feed in layers fed JC (P < 0.01). Although eggs from layers fed NM were 0.7 g heavier than controls, eggs from layers fed NC, JM or JC were 1.4 g lighter than controls (P < 0.01). Eggs from layers fed Brassica diets contained a greater proportion (1.6%-points) of monounsaturated fatty acids compared with controls (P < 0.01). Eggs from layers fed B. juncea had a relatively greater proportion (0.2%-points) of C18:3 (n3) compared with those of layers fed B. napus diets (P < 0.01). Feeding Brassica diets reduced digestibility of DM (5%-points), gross energy (7%-points) and CP (4%-points) vs. basal (P < 0.01). The digestibility of indispensable AA except tryptophan, was reduced feeding Brassica diets vs. basal (P < 0.01). We concluded that feeding B. napus and B. juncea extruded-expelled cakes and solvent-extracted meal at 20% of diets to hens supported acceptable lay performance and egg quality over a 36 wk production cycle. Digestibility data indicated that indispensable AA in Brassica co-products had moderately high (75 to 85%) apparent ileal digestibility.