Intake and digestibility by gestating sheep of alfalfa silage wrapped with or without an enhanced oxygen barrier plastic after time delays up to three days

• Published in: Animal feed science and technology Vol. 254; p. 114193
• Main Authors: Niyigena, V., Coffey, K.P., Coblentz, W.K., Philipp, D., Rhein, R.T., Young, A.N., Caldwell, J.D., Shanks, B.C.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2019
• Subjects: Alfalfa silage; Digestibility; Forage intake; Sheep; But; DMI; aNDF; Ace; ADF; NH3N-CPE; DM; Tempmax; OMI; Forage intake; Pro; TA; N; CW; Lactic; LTA; EOB; Sheep; OM; Alfalfa silage; Digestibility
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/j.anifeedsci.2019.05.016

•Alfalfa silage dry matter, organic matter, digestible dry matter and organic matter intake were greatest when the round bales were wrapped the day after baling.•Delayed wrapping of alfalfa round bales beyond 24 h after baling reduced voluntary intake and digestibility by sheep.•Wrapping alfalfa silage with a plastic with an enhanced oxygen barrier had little effect on intake or digestibility by sheep, possibly because 7 layers of plastic were used. Poor silage fermentation can affect its acceptance by livestock. Alfalfa from 3 field blocks were baled in large round bales (moisture concentration = 591 ± 43.0 g/kg) and then wrapped with 7 layers of plastic either with (EOB) or without (CW) an enhanced oxygen barrier on the day of baling, or 1, 2 or 3 d after baling in order to examine those effects on subsequent intake and digestibility by gestating sheep. Alfalfa was chopped after approximately 5 mo. of fermentation, and then offered for individual ad libitum consumption by 16 gestating ewes [63.5 ± 1.71 kg avg. body weight (BW)] in a 3-period (63-day) digestion study. Silage moisture and nitrogen (N) decreased linearly (P < 0.05), acid-detergent fiber (ADF) increased linearly (P < 0.05), and neutral-detergent fiber (aNDF) increased at a decreasing rate (linear; quadratic P < 0.05) with wrapping delay within EOB but not CW (P ≥ 0.23). Lactic acid expressed as g/kg of total silage acids decreased linearly (P < 0.05) within CW and decreased at an increasing rate (linear; quadratic P < 0.05) within EOB with increasing wrapping delay, likely because of aerobic deterioration. Digestible organic matter intake (DOMI) decreased linearly (P =  0.03) within EOB and quadratically (P =  0.02) within CW (wrap type × wrapping time after baling interaction; P =  0.04), but other intake and digestibility measurements were not affected (P ≥  0.15) by wrap type or its interaction with wrapping time after baling. Intake of DM and OM (DMI and OMI, g/kg BW) as well as digestible DMI (g/kg BW) responded linearly and quadratically (P ≤ 0.03) with wrapping delay after baling by initially increasing to 1 d after baling, then declining sharply thereafter. Digestibility of aNDF increased linearly (P = 0.04) with wrapping delay which was likely related to reduced DMI. These values align somewhat closely with those for forage quality and fermentation profiles. Therefore, managing alfalfa silage to ensure more desirable fermentation should also result in higher digestible OMI, which will improve the overall energy status of ruminants.