@article{dschaak_noviandi_eun_fellner_young_zobell_israelsen_2011, title={Ruminal fermentation, milk fatty acid profiles, and productive performance of Holstein dairy cows fed 2 different safflower seeds}, volume={94}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2011-4541}, abstractNote={A lactation trial was conducted to determine the effects of supplementing whole safflower seeds (SS) on ruminal fermentation, lactational performance, and milk fatty acid (FA) profiles. Nine multiparous Holstein cows (days in milk = 110 ± 20) were used in a replicated 3 × 3 Latin square design. Each period lasted 21 d, with 14 d of adaptation and 7 d of data collection. Within square, cows were randomly assigned to a sequence of 3 dietary treatments as follows: cottonseed total mixed ration (TMR; CST), conventional SS (variety S-208) TMR (CSST), and NutraSaff SS (Safflower Technologies International, Sidney, MT) TMR (NSST). Diets contained approximately 63% forage (36% alfalfa hay, 4% grass hay, and 23% corn silage) and 37% concentrate supplemented with 2% cottonseed to the CST and 3% conventional or NutraSaff SS to the CSST or the NSST, respectively. Intake of dry matter (DM) averaged 21.8 kg/d and did not differ across diets, but feeding the NSST decreased intake of neutral detergent fiber (NDF) due to lower dietary concentration of NDF in the NSST. Digestibilities of DM and nutrients were similar among treatments. No differences in yields of milk or milk components were observed in response to supplementing SS. Dietary treatments did not affect ruminal pH, total or molar proportions of ruminal volatile FA, and ammonia-N. However, cows fed SS had a higher molar proportion of isobutyrate than those fed the CST diet. Ruminal C16:0 FA concentration increased with the CST, whereas C18:1 cis-9 and C18:2 n-6 tended to increase with SS supplementation, indicating that conventional and NutraSaff SS were partially protected from microbial biohydrogenation. Supplementing SS decreased milk C16:0 concentration, whereas it increased C18:1 cis-9 and C18:1 trans-9. Milk FA C18:1 trans-11 and cis-9, trans-11 conjugated linoleic acid increased and tended to increase with feeding the NSST, respectively, but not the CSST diet. In conclusion, supplementing diets with whole SS at 3% of dietary DM can be an effective strategy of fat supplementation to lactating dairy cows without negative effects on lactational performance and milk FA profiles.}, number={10}, journal={JOURNAL OF DAIRY SCIENCE}, author={Dschaak, C. M. and Noviandi, C. T. and Eun, J. -S. and Fellner, V. and Young, A. J. and ZoBell, D. R. and Israelsen, C. E.}, year={2011}, month={Oct}, pages={5138–5150} }
 @article{eun_fellner_burns_gumpertz_2004, title={Fermentation of eastern gamagrass (Tripsacum dactyloides [L.] L.) by mixed cultures of ruminal microorganisms with or without supplemental corn}, volume={82}, DOI={10.2527/2004.821170x}, abstractNote={Five dual-flow fermentors (700 mL) were used to determine the effects of eastern gamagrass (Tripsacum dactyloides [L.] L.) diets on microbial metabolism by mixed rumen cultures. Fermentors were incubated with filtered ruminal contents and allowed to adapt for 4 d to diets followed by 3 d of sample collection. Five dietary treatments were tested: 1) gamagrass hay (GH) + no corn (GHNC), 2) gama grass silage (GS) + no corn (GSNC), 3) GS + low corn (GSLC), 4) GS + medium corn (GSMC); and 5) GS + high corn (GSHC). The experiment was conducted as a randomized complete block design with five treatments and three replications. Total VFA concentrations were not affected by diets. Corn addition linearly decreased (P < 0.001) molar proportion of acetate. In contrast, molar proportion of propionate was reduced in GSLC (cubic effect, P < 0.001) but remained similar across other diets. Corn supplementation linearly increased molar proportion of butyrate (P < 0.001). The acetate + butyrate-to-propionate ratio was highest in cultures offered GSLC (cubic effect, P < 0.001) but similar across other diets. Feeding GSNC resulted in a higher ruminal pH compared with GHNC (P < 0.03). Increasing the level of corn supplementation in GS linearly decreased culture pH (P < 0.001). All diets resulted in similar methane production, with the exception of GSMC, which lowered methane output (quadratic effect, P < 0.004). Total substrate fermented to VFA and gas tended to be greater with GHNC than with GSNC (P < 0.06) and linearly increased with the addition of corn (P < 0.004). Neutral detergent fiber digestibility was similar between GH and GS and was not affected by supplemental corn. Microbial N flow increased in cultures offered GSHC (quadratic effect, P < 0.02). Corn supplementation at the medium and high level linearly decreased C 18:0 (P < 0.02) and increased trans-C18:1 (P < 0.004). Including corn at the high level with GS did not have a detrimental effect on fermentation in dual-flow fermentors.}, number={1}, journal={Journal of Animal Science}, author={Eun, J. S. and Fellner, Vivek and Burns, J. C. and Gumpertz, M. L.}, year={2004}, pages={170–178} }
 @article{eun_fellner_gumpertz_2004, title={Methane production by mixed ruminal cultures incubated in dual-flow fermentors}, volume={87}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(04)73148-3}, abstractNote={This study evaluated the effects of dilution rate and forage-to-concentrate ratio on gas production by rumen microbes. Continuous cultures were used to monitor methane production at three liquid dilution rates (3.2, 6.3, or 12.5%/h) and three forage-to-concentrate ratios (70:30, 50:50, or 30:70). Filtered ruminal contents were allowed 6 d of adaptation to diets followed by 7 d of data collection. Forage consisted of pelleted alfalfa and the concentrate mix included ground corn, soybean meal, and a mineral and vitamin premix. The experiment was replicated in a split-plot design. Total volatile fatty acid production averaged 58.0 mmol/d and was not affected by treatment. Molar proportion of acetate increased with increasing forage-to-concentrate ratio. Molar proportion of propionate tended to decrease at dilution rate of 12.5%/h and increased with the medium and low forage-to-concentrate ratio. Culture pH tended to be greater at a dilution rate of 12.5%/h. Methane production that was calculated from stoichiometric equations was not affected by treatments. However, methane production based on methane concentration in fermentor headspace resulted in an interaction effect of treatments. Stoichiometric equations underestimated methane output at higher dilution rates and with high forage diets. Total diet fermentability was lowest at dilution rate of 3.2%/h. Increasing dilution rates increased microbial yield; increasing the proportion of concentrate improved microbial efficiency. Dilution rate and forage-to-concentrate ratio altered the partition of substrate by microbes. Methane production based on actual concentrations differed from values estimated using stoichiometry of end-product appearance.}, number={1}, journal={JOURNAL OF DAIRY SCIENCE}, author={Eun, JS and Fellner, V and Gumpertz, ML}, year={2004}, month={Jan}, pages={112–121} }
 @article{eun_fellner_burns_gumpertz_2003, title={Eastern gamagrass evaluated as hay or silage for lactating dairy cows}, volume={19}, ISBN={1080-7446}, DOI={10.15232/s1080-7446(15)31442-x}, abstractNote={Twenty lactating Holstein cows were used to determine the nutritional value of eastern gamagrass. Dietary treatments consisted of 1) gamagrass hay and no corn (HNC), 2) gamagrass silage (S) and no corn (SNC), 3) S and low corn (SLC), 4) S and medium corn (SMC), and 5) S and high corn (SHC). Gamagrass fed as hay or silage did not change (P>0.10) milk yield, but corn inclusion tended to increase (P<0.08) milk yield. Yields of milk protein (0.69 vs 0.80 kg/d), lactose (1.23 vs 1.44 kg/d), and solids-not-fat (2.12 vs 2.48 kg/d) tended to be greater for SNC than for HNC (P<0.08). Corn inclusion increased milk yields compared with SNC. Gamagrass fed as silage resulted in a greater feed conversion efficiency than did gamagrass fed as hay (2.16 vs 1.88; P<0.01). Adding corn to S reduced feed efficiency. Conversion of feed N to milk N was greater (P<0.01) for gamagrass fed as silage than for hay. Milk urea N (MUN) concentration was greater (P<0.01) for cows fed HNC than for cows on all other treatments. Feeding S significantly lessened MUN concentration. Including corn at the medium and high levels further reduced MUN concentration (P<0.05). Increased energy from corn at the high level increased milk yield and tended to increase conversion of feed N into milk protein. Gamagrass fed as silage without or with corn improved the N status of the cows, as indicated by lesser MUN concentrations.}, number={5}, journal={Professional Animal Scientists}, author={Eun, J. S. and Fellner, Vivek and Burns, J. C. and Gumpertz, M. L.}, year={2003}, pages={362} }