TY - JOUR
T1 - Effects of different doses of 3-nitrooxypropanol combined with varying forage composition on feed intake, methane emission, and milk production in dairy cows
AU - Maigaard, Morten
AU - Weisbjerg, Martin R.
AU - Ohlsson, Christer
AU - Walker, Nicola
AU - Lund, Peter
N1 - Publisher Copyright:
© 2025 American Dairy Science Association
PY - 2025/3
Y1 - 2025/3
N2 - The objective of this study was to investigate the effect of combining different doses of 3-nitrooxypropanol (3-NOP) with varying forage composition on gas emission and production performance of dairy cows. Seventy-two lactating Danish Holstein cows (36 primiparous and 36 multiparous) were enrolled in a continuous randomized block design with an initial 2-wk covariate period followed by application of treatments for 12 consecutive weeks. Initial DMI and ECM yield were 23.8 ± 3.34 kg/d (mean ± SD) and 38.3 ± 7.12 kg/d, respectively. Cows were blocked according to parity and DIM. Treatments were organized in a 2 × 3 factorial arrangement. The first factor was diet type, reflecting 2 different forage compositions of the diet. The ratio of grass-clover silage to corn silage was 60%:40% of total forage DM in grass-based diets and 40%:60% in corn-based diets. In total, forage constituted 56% of the DM in the partial mixed rations. The second factor reflected 3 doses of 3-NOP: 0, 60, or 80 mg 3-NOP/kg DM. Gas emissions were measured using GreenFeed systems and feed intake by using Insentec Roughage Intake Control bins. Weekly averages from the last 10 wk were analyzed by using a mixed model including fixed effects and interactions among diet type, 3-NOP dose, week, and parity, and included a covariate term and accounted for repeated measures. Methane yield (g/kg DMI) was reduced by 34% and 31%, and CH4 intensity (g/kg ECM) was reduced by 34% and 32% at 60 and 80 mg 3-NOP/kg DM, respectively, and we found no difference in CH4 yield or intensity between the 2 doses. The corn- and grass-based diets were similar in NDF and starch levels, and we found no interaction between dose of 3-NOP and diet type for CH4 yield or intensity. Total DMI was reduced by 9% in cows fed 80 mg 3-NOP/kg DM across diet types, whereas we found no effect on DMI at 60 mg 3-NOP/kg DM. Similarly, ECM yield was reduced by 5% in cows fed 80 mg 3-NOP/kg DM compared with no 3-NOP supplementation, and these cows had a 42% lower BW increase over the experiment compared with no supplementation. In conclusion, 3-NOP at 60 mg/kg DM was efficient in reducing CH4 without compromising feed intake and milk production, whereas 80 mg 3-NOP/kg DM negatively affected production performance.
AB - The objective of this study was to investigate the effect of combining different doses of 3-nitrooxypropanol (3-NOP) with varying forage composition on gas emission and production performance of dairy cows. Seventy-two lactating Danish Holstein cows (36 primiparous and 36 multiparous) were enrolled in a continuous randomized block design with an initial 2-wk covariate period followed by application of treatments for 12 consecutive weeks. Initial DMI and ECM yield were 23.8 ± 3.34 kg/d (mean ± SD) and 38.3 ± 7.12 kg/d, respectively. Cows were blocked according to parity and DIM. Treatments were organized in a 2 × 3 factorial arrangement. The first factor was diet type, reflecting 2 different forage compositions of the diet. The ratio of grass-clover silage to corn silage was 60%:40% of total forage DM in grass-based diets and 40%:60% in corn-based diets. In total, forage constituted 56% of the DM in the partial mixed rations. The second factor reflected 3 doses of 3-NOP: 0, 60, or 80 mg 3-NOP/kg DM. Gas emissions were measured using GreenFeed systems and feed intake by using Insentec Roughage Intake Control bins. Weekly averages from the last 10 wk were analyzed by using a mixed model including fixed effects and interactions among diet type, 3-NOP dose, week, and parity, and included a covariate term and accounted for repeated measures. Methane yield (g/kg DMI) was reduced by 34% and 31%, and CH4 intensity (g/kg ECM) was reduced by 34% and 32% at 60 and 80 mg 3-NOP/kg DM, respectively, and we found no difference in CH4 yield or intensity between the 2 doses. The corn- and grass-based diets were similar in NDF and starch levels, and we found no interaction between dose of 3-NOP and diet type for CH4 yield or intensity. Total DMI was reduced by 9% in cows fed 80 mg 3-NOP/kg DM across diet types, whereas we found no effect on DMI at 60 mg 3-NOP/kg DM. Similarly, ECM yield was reduced by 5% in cows fed 80 mg 3-NOP/kg DM compared with no 3-NOP supplementation, and these cows had a 42% lower BW increase over the experiment compared with no supplementation. In conclusion, 3-NOP at 60 mg/kg DM was efficient in reducing CH4 without compromising feed intake and milk production, whereas 80 mg 3-NOP/kg DM negatively affected production performance.
KW - Bovaer
KW - feed additive
KW - grass-based
KW - maize-based
UR - http://www.scopus.com/inward/record.url?scp=85219040965&partnerID=8YFLogxK
U2 - 10.3168/jds.2024-25343
DO - 10.3168/jds.2024-25343
M3 - Journal article
C2 - 39701524
AN - SCOPUS:85219040965
SN - 0022-0302
VL - 108
SP - 2489
EP - 2502
JO - Journal of Dairy Science
JF - Journal of Dairy Science
IS - 3
ER -