|ANDERSON, JILL - South Dakota State University|
|GARCIA, ALVARO - South Dakota State University|
|SCHINGOETHE, DAVID - South Dakota State University|
Submitted to: Journal of Dairy Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/2015
Publication Date: 8/1/2015
Publication URL: https://handle.nal.usda.gov/10113/62849
Citation: Anderson, J.L., Kalscheur, K., Garcia, A.D., Schingoethe, D.J. 2015. Feeding fat from distillers dried grains with solubles to dairy heifers: I. Effects on growth performance and total tract digestibility of nutrients. Journal of Dairy Science. 98:5699-5708.
Interpretive Summary: Distillers dried grains with solubles (DDGS), a byproduct of the ethanol industry, is an economic feed source for dairy cattle and is used extensively in ruminant diets. But there have been questions about feeding it to dairy heifers, with one concern being that the high fat level might negatively affect nutrient digestibility and growth performance of heifers. In this study, for 24 weeks Holstein heifers were fed three different diets containing: 1) soybean products with ground corn; 2) low-fat DDGS with ground corn; or 3) high-fat traditional DDGS. The digestibility of protein and fiber were greater for the high-fat DDGS diet compared to the other diets, but overall digestibilities were similar. This information gives dairy producers assurance that feeding high-fat traditional DDGS does not affect growth performance of dairy heifers and can be a good option when looking for low-cost feed ingredients.
Technical Abstract: The objective of this study was to determine if increased dietary fat from dried distillers grains with solubles (DDGS) in diets of growing heifers affected dry matter intake (DMI), average daily gain (ADG), growth performance, and nutrient digestibility. Thirty-three Holstein heifers (133 ± 18 d old) were used in a 24-wk randomized complete block design. Treatments were: 1) control (CON) containing ground corn (15.9% of dry matter (DM)) and soybean products (17.9%); 2) low-fat (LFDG) containing low-fat, high-protein dried distillers grains (21.9%) and ground corn (11.9%); and 3) high-fat (HFDG) with traditional dried distillers grains with solubles (33.8%). All diets contained 39.8% grass hay, 24.8% corn silage, and 1.5% vitamins and minerals. Diets were formulated for 16.3% CP (DM basis) 9.8% rumen-degradable protein and 6.5% rumen-undegradable protein. The HFDG diet was formulated to contain 4.8% fat compared to 2.8% in the CON and LFDG diets, which were greater in non-fibrous carbohydrate. Diets had a net energy gain of 1.0 Mcal/kg of DM and were limit-fed at 2.45% of body weight. Heifers were weighed every 2 wk and rations were adjusted accordingly. Heart girth, hip and wither heights, body length, and BCS were recorded every 2 wk. Total tract digestion of nutrients was evaluated during wk 16 using an external marker. No treatments by time interactions were found. Dry matter intakes, body weights, average daily gain, and gain to feed ratio were similar among treatments. All body frame measurements and body condition scores were similar among treatments. Total tract digestibilities of DM and organic matter were similar among treatments. However, crude protein digestibility and neutral detergent fiber digestibility were increased in HFDG diet compared to CON and LFDG diets. These results demonstrate that DDGS or low-fat DDGS used in growing heifer rations can maintain performance. Utilizing the fat in DDGS as a dietary energy source in replacement of starch from corn did not influence growth performance or negatively impact nutrient digestion.