TY - JOUR

T1 - Effect of ryegrass hay and ryegrass silage, cut at two stages of development, on nutrient digestibility, nitrogen balance, and purine derivative excretion in growing sheep

AU - Gonzalez-Ronquillo, Manuel

AU - Robles-Jiménez, Lizbeth E.

AU - Romero-Bernal, Jose

AU - Ariciaga-Gonzalez, Cynthia

AU - Valdez-Ramírez, Bulmaro

AU - Chay-Canul, Alfonso J.

AU - Vargas-Bello-Pérez, Einar

N1 - Publisher Copyright: © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

PY - 2021

Y1 - 2021

N2 - The objective of this study was to evaluate nutrient digestibility, nitrogen balance, and purine derivative excretion from growing sheep fed on ryegrass silage (S) or ryegrass hay (H) cut at two maturity stages (21 and 35 d). In an in vivo trial, 32 Suffolk × Merino growing sheep (22 ± 2 kg) were used in a completely randomised design with eighth replications in a 2 × 2 factorial arrangement. Four diets were used containing 75% forage (S at 21 or 35 d and H at 21 or 35 d) and 25% concentrate. In an in vitro trial, a completely randomised design was used for gas production parameters. Contents of N and NDF were higher in H (30 and 674 g/kg DM) than in S (26 and 411 g/kg DM). Animals fed on S had higher digestibility (P <.008) of DM and OM (661 and 715 g/kg) than H at 35 d (557 and 596 g/kg). In vitro gas production was lower (P <.04) in H at 35 d. In vitro DM disappearance at 96 h was lower (P <.03) for H at 35 d. Excretion of allantoin (mmol/day) in urine was higher (P <.001) in S (7.91 and 3.95) than H (5.01 and 3.03) at 21 and 35 d respectively. Overall, compared to ryegrass hay, ryegrass silage cut at 21 d can be an advantageous feeding strategy for growing sheep without negative effects in nutrient intake, N-balance, and purine derivatives.Highlights Contents of N and NDF were higher in hay than in silage form ryegrass. Animals fed on silage had higher digestibility of DM and OM. In vitro gas production was lower in hay cut at 35 days.

AB - The objective of this study was to evaluate nutrient digestibility, nitrogen balance, and purine derivative excretion from growing sheep fed on ryegrass silage (S) or ryegrass hay (H) cut at two maturity stages (21 and 35 d). In an in vivo trial, 32 Suffolk × Merino growing sheep (22 ± 2 kg) were used in a completely randomised design with eighth replications in a 2 × 2 factorial arrangement. Four diets were used containing 75% forage (S at 21 or 35 d and H at 21 or 35 d) and 25% concentrate. In an in vitro trial, a completely randomised design was used for gas production parameters. Contents of N and NDF were higher in H (30 and 674 g/kg DM) than in S (26 and 411 g/kg DM). Animals fed on S had higher digestibility (P <.008) of DM and OM (661 and 715 g/kg) than H at 35 d (557 and 596 g/kg). In vitro gas production was lower (P <.04) in H at 35 d. In vitro DM disappearance at 96 h was lower (P <.03) for H at 35 d. Excretion of allantoin (mmol/day) in urine was higher (P <.001) in S (7.91 and 3.95) than H (5.01 and 3.03) at 21 and 35 d respectively. Overall, compared to ryegrass hay, ryegrass silage cut at 21 d can be an advantageous feeding strategy for growing sheep without negative effects in nutrient intake, N-balance, and purine derivatives.Highlights Contents of N and NDF were higher in hay than in silage form ryegrass. Animals fed on silage had higher digestibility of DM and OM. In vitro gas production was lower in hay cut at 35 days.

KW - Allantoin

KW - in vitro

KW - purine derivatives

KW - rumen fermentation

KW - ryegrass

U2 - 10.1080/1828051X.2021.2000342

DO - 10.1080/1828051X.2021.2000342

M3 - Journal article

AN - SCOPUS:85119452801

VL - 20

SP - 2110

EP - 2121

JO - Italian Journal of Animal Science

JF - Italian Journal of Animal Science

SN - 1594-4077

IS - 1

ER -