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Nonenzymatically browned soybeans and soybean coproducts for lactating dairy cows
Abstract
The hypothesis tested was that supplemental lipid from nonenzymatically browned soybeans and soy lipid coproducts would reduce the negative impact of lipids on ruminal metabolism compared with soybean oil and would improve the milk fatty acid composition compared with calcium salts of fatty acids. In the first experiment, the soybean oil diet reduced the rate and apparent extent of ruminal NDF digestion and decreased the acetate to propionate ratio. The diets containing 4 and 6% lipid from nonenzymatically browned soybeans had an intermediate rate and apparent extent of ruminal NDF digestion. Additionally, the nonenzymatically browned soybean diets increased milk C18:2 fatty acids by 35% compared with soybean oil, whereas C18:1 and C18:0 fatty acids were reduced. In the second experiment, increasing nonenzymatically browned soybean concentration in the diet linearly increased milk fat production. All levels of the nonenzymatically browned soybeans tested resulted in FCM similar to the calcium salts of fatty acid diet, and higher than the soybean oil diet, but with more desirable milk fatty acid profiles. Two experiments were conducted to determine the effects of soyhull:soy lecithin:soapstock mixtures on ruminal fermentation, milk composition, and ruminal bacterial and protozoal populations. In experiment 1, cows fed the lecithin and soapstock diets had higher milk C18:2 fatty acids and higher rate of ruminal NDF digestion than cows fed the soybean oil diet. When tested in a semi-continuous in vitro system, substrates containing 18% of a mixture of lecithin and soapstock had higher acetate to propionate ratio than substrates containing a similar concentration of soybean oil. Also, higher total protozoal counts were observed for the lecithin and soapstock treatments than those with no lipid added. These results indicate that the nonenzymatically browned soybean and soy lipid coproducts have less negative effect on ruminal fermentation than soybean oil and may be useful as a partially protected lipid supplement for dairy cows.
Subject Area
Livestock
Recommended Citation
Abel-Caines, Silvia F, "Nonenzymatically browned soybeans and soybean coproducts for lactating dairy cows" (1996). ETD collection for University of Nebraska-Lincoln. AAI9703770.
https://digitalcommons.unl.edu/dissertations/AAI9703770