Impacts of dietary fat level and saturation when feeding distillers grains to high producing dairy cows

• Published in: Journal of animal physiology and animal nutrition Vol. 99; no. 3; pp. 577 - 590
• Main Authors: Havlin, J. M, Robinson, P. H, Karges, K
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Science 01.06.2015; Blackwell Publishing Ltd; Wiley Subscription Services, Inc
• Subjects: acid detergent fiber; Animal Feed - analysis; animal performance; Animals; beet pulp; Body Composition; body condition; Cattle - physiology; corn; dairy cows; Diet - veterinary; dietary fat; Dietary Fats - administration & dosage; digestibility; distillers; distillers grains; dried distillers grains with solubles; early lactation; Edible Grain - chemistry; energy; Energy Metabolism; Fatty Acids, Unsaturated - chemistry; Fatty Acids, Unsaturated - pharmacology; Female; high fat diet; Lactation - physiology; lipid metabolism; milk; Milk - chemistry; milk fat depression; milk fatty acids; RI fat; rumen; saturated; saturated fats; total mixed rations; true protein; unsaturated; unsaturated fats; unsaturated fatty acids; dried distillers grains with solubles; RI fat; saturated; milk fat depression; distillers; unsaturated
• ISSN: 0931-2439; 1439-0396
• DOI: 10.1111/jpn.12219

This experiment was conducted to determine whether increasing the net energy (NEL) of a total mixed ration (TMR) with mainly unsaturated fat from corn distillers dried grains with solubles (DDGS) vs. rumen inert (RI)‐saturated fat has similar impacts on animal performance. The experiment was an incomplete Youden square with three treatments and four 28‐days periods, completed on a large commercial dairy using three early lactation pens each with approximately 380 multiparity cows. The TMR for all treatments was the same, except for 150 g/kg dry matter (DM) of each TMR which contained 90 g/kg high‐protein DDGS (HPDDGS) and 60 g/kg beet pulp (i.e. low‐fat control diet; LFC); 150 g/kg DDGS (i.e. high‐fat diet with unsaturated fat; HFU); or 111 g/kg HPDDGS, 20 g/kg beet pulp and 19 g/kg RI fat (i.e. high‐fat diet with saturated fat; HFS). The DM intake was highest (p < 0.05) for HFU‐fed cows. Milk, fat and true protein yields, as well as milk energy output, were higher (p < 0.01) when cows were fed HFS vs. HFU and LFC diets. Milk true protein concentration was lowest (p < 0.01) for HFS‐fed cows, but milk fat % was lowest (p < 0.01) for HFU and highest (p < 0.01) for HFS‐fed cows. There were numerous differences (p < 0.01) in milk fatty acid levels amongst diets. The increase in body condition score was lowest (p < 0.01) for LFC. Whole tract digestibility of acid detergent fibre was lower (p < 0.01) for LFC vs. HFS cows, and fat digestion was lowest (p < 0.01) for LFC‐fed cows. This DDGS, high in unsaturated fatty acids, was fed at high levels (i.e. 152 g/kg DM) with little impact on animal performance vs. a lower fat control diet, although addition of an RI‐saturated fat to create a diet with a similarly higher fat level resulted in higher animal productivity.