Digestibility of grass fibre increased by screw pressing in a bio-refinery

TY - ABST

T1 - Digestibility of grass fibre increased by screw pressing in a bio-refinery

AU - Hansen, Nikolaj Peder

AU - Weisbjerg, Martin Riis

AU - Johansen, Marianne

AU - Jensen, Søren Krogh

PY - 2021/8

Y1 - 2021/8

N2 - In this study, the effects of screw-pressing prior to ensiling and days of regrowth of perennial ryegrass on fibre digestibility were investigated. Six rumen and duodenal fistulated, multiparous Holstein cows (176±93 days in milk;mean ± SD) were used in an incomplete 6×4 Latin square design with four periods and a 2×3 factorial arrangement of treatments. The factors were developmental stage of grass at harvest [early (ERL; 35 days of regrowth) and late (LAT; 44 days of regrowth)] and processing prior to ensiling [traditional grass silage (GS; mowed, wilted, and chopped), pulp pressed once (1×P; fresh grass processed using twin-screw press producing the two fractions pulp and green juice), and pulp pressed twice (2×P; half of 1×P was soaked in water and processed a second time)]. Grass of all six treatments ensiled for four months before the digestibility experiment started. A total mixed ration with experimental silages, soybean meal, rolled wheat, and minerals (65.0, 6.60, 26.6, and 1.80% of DM, respectively) was fed in periods of 21 days duration. Two markers (titanium dioxide and chromic oxide) were dosed in the rumen twice a day to determine flow of digesta in duodenum and output in faeces. A model including developmental stage, processing, developmental stage × processing, and period as fixed effects, and cow as random effect was analysed in R. Acrossdevelopmental stage, DM intake was lower (14.9 vs 17.5 kg/d; P<0.01) and NDF intake was higher (7.07 vs 5.92 kg/d; P<0.01) for 2×P compared to GS. For rumen and total tract NDF digestibility, an interaction was found betweendevelopmental stage and processing (P<0.05). No effect of processing was observed for ERL (average rumen and total tract NDF digestibility were 73.3 and 76.5%), but an increase was observed with increased processing intensityfor LAT (66.2, 71.5, and 76.6% for rumen, and 71.6, 73.8, and 78.3% for total tract NDF digestibility, for GS, 1×P, and 2×P, respectively). Across developmental stage, the amount of NDF digested in the total tract was higher for 2×Pcompared to GS (5.47 vs 4.36 kg/d; P<0.01). The study showed that processing can increase intake of fibre and that processing has the greatest effect on fibre digestibility in more developed grass.

AB - In this study, the effects of screw-pressing prior to ensiling and days of regrowth of perennial ryegrass on fibre digestibility were investigated. Six rumen and duodenal fistulated, multiparous Holstein cows (176±93 days in milk;mean ± SD) were used in an incomplete 6×4 Latin square design with four periods and a 2×3 factorial arrangement of treatments. The factors were developmental stage of grass at harvest [early (ERL; 35 days of regrowth) and late (LAT; 44 days of regrowth)] and processing prior to ensiling [traditional grass silage (GS; mowed, wilted, and chopped), pulp pressed once (1×P; fresh grass processed using twin-screw press producing the two fractions pulp and green juice), and pulp pressed twice (2×P; half of 1×P was soaked in water and processed a second time)]. Grass of all six treatments ensiled for four months before the digestibility experiment started. A total mixed ration with experimental silages, soybean meal, rolled wheat, and minerals (65.0, 6.60, 26.6, and 1.80% of DM, respectively) was fed in periods of 21 days duration. Two markers (titanium dioxide and chromic oxide) were dosed in the rumen twice a day to determine flow of digesta in duodenum and output in faeces. A model including developmental stage, processing, developmental stage × processing, and period as fixed effects, and cow as random effect was analysed in R. Acrossdevelopmental stage, DM intake was lower (14.9 vs 17.5 kg/d; P<0.01) and NDF intake was higher (7.07 vs 5.92 kg/d; P<0.01) for 2×P compared to GS. For rumen and total tract NDF digestibility, an interaction was found betweendevelopmental stage and processing (P<0.05). No effect of processing was observed for ERL (average rumen and total tract NDF digestibility were 73.3 and 76.5%), but an increase was observed with increased processing intensityfor LAT (66.2, 71.5, and 76.6% for rumen, and 71.6, 73.8, and 78.3% for total tract NDF digestibility, for GS, 1×P, and 2×P, respectively). Across developmental stage, the amount of NDF digested in the total tract was higher for 2×Pcompared to GS (5.47 vs 4.36 kg/d; P<0.01). The study showed that processing can increase intake of fibre and that processing has the greatest effect on fibre digestibility in more developed grass.

U2 - 10.3920/978-90-8686-918-3

DO - 10.3920/978-90-8686-918-3

M3 - Conference abstract in proceedings

SN - 978-90-8686-366-2

T3 - EAAP Book of Abstracts

SP - 336

EP - 336

BT - Book of Abstracts of the 72nd Annual Meeting of the European Federation of Animal Science

A2 - Strandberg, E.

A2 - Pinotti, L.

A2 - Messori, S.

A2 - Kenny, D.

A2 - Lee, M.

A2 - Hocquette, J.F.

A2 - Cadavez, V.A.P.

A2 - Millet, S.

A2 - Evans, R.

A2 - Veldkamp, T.

A2 - Pastell, M.

A2 - Pollott, G.

PB - Wageningen Academic Publishers

T2 - 72nd Annual Meeting of the European Federation of Animal Science

Y2 - 29 August 2021 through 3 September 2021

ER -