Results from a self-administered survey carried out by South Dakota State University dairy researchers among 49 dairy producers showed soybean meal was the protein source most frequently used in their rations (64% of producers), and canola meal was fed by 22% of the producers. These finding agreed with a previous survey carried out by the University of Missouri that showed soybean meal was the source of protein most commonly used in dairy cattle diets (except in the Southwest) with 90% of the lactating cows in the Midwest being fed soybean meal. On the other hand, 17% of the cows were fed canola meal.
A study published recently by University of Manitoba researchers (2016) evaluated the amino acid (AA) content of canola meal from Canadian processing facilities. The authors analysed samples collected from 11 canola plants over four successive years (2011-2014). The contents of essential AA are shown in Table 1. Among essential AA, leucine (6.22% of protein), arginine (5.45%) and lysine (5.06%) were the most abundant. These results agree with another work from the University of Nebraska (2014) in which the concentration of leucine, arginine, and lysine were 7.07, 5.93, and 5.36% of protein, respectively.
These values of the essential AA leucine and lysine found on these two studies were similar to the values reported in the National Research Council 2001 (6.77 and 5.62% of protein, respectively); however, arginine concentration was lower (7.01%).
Continue reading this article published in International Dairy Topics.
