Composition of flaxseed recovered from the faeces of dairy cows fed different proportions of whole flaxseed in the diet

Intake, digestibility and recovery of grains from feces of steers fed different oilseeds

ABSTRACT Oilseed grains are used as a protein and energy source, increasing the energy density of the feed. The goal of the present study was to determine the nutritional profile of canola, crambe and soybean grains recovered from feces, and to evaluate the intake and digestibility of nutrients, rumen fermentation parameters of beef cattle receiving whole grains of oilseeds. Three steers, 350 ± 23.5 kg body weight were distributed in a not contemporary, 3 × 3 double Latin square, and fed oilseed grains. Inclusion of crambe grain reduced dry matter intake by 21.02%, with a higher digestibility coefficient for EE and NDF. The crude protein content of canola and crambe grains recovered were similar, but the EE content was higher for the crambe grain (26.46%). Soybean showed the lowest values of chemical composition for grains recovered from feces. The highest dry matter intake (7.86 kg/day), and the lowest NDF digestibility (0.203g/kg), were found for animals fed soybean. The inclusion of crambe grains reduced the rumen ammonia content (10.97 mg/dL); however, the ruminal pH was not altered by the inclusion of grains in the diet. Canola and soybean grains can be included in the cattle diet without altering dry matter intake; while the inclusion of crambe grains reduces the dry matter intake and the ruminal ammonia content of the animals. Crambe grain showed the highest recovery of dry matter and ether extract from feces.