Influence of canola fat on yield, fat percentage, fatty acid profile, and nitrogen fractions in Holstein milk.

Effects of canola fat on feed intake, yield, and composition of milk of early lactation dairy cows were investigated. Concentrate mixtures containing 0, 2.5, 5.0, 7.3, and 9.6% added fat as Jet-Sploded whole canola seed (0, 4.5, 9.0, 13.2, and 17.4% of DM, respectively) were fed to 15 cows in diets containing 60% concentrate and 40% forage (DM basis). Diets contained 16.5% CP, 30% alfalfa silage, and 10% whole crop oat silage (DM basis). There was a trend for a cubic effect on DMI, a quadratic effect on milk yield, and a small, but significant, linear decrease in milk protein percentage with increasing level of canola seed; the decrease was primarily in the casein fraction. Although milk fat percentage was not altered, addition of Jet-Sploded canola seed caused a substantial reduction in some short- and medium-chain fatty acids and a concomitant increase of as much as 65% in the concentration of C18:1. Results suggest that canola fat from Jet-Sploded whole canola seed can be included up to 5% of dietary DM without negative effects on DMI and with a net positive effect on milk yield.