Digestion of timothy silage and hay in reindeer

Abstract

Leafy timothy (Phleum pratense) silage (S), silage mixed with molasses (SM) and hay (H) were fed to nine male reindeer (Rangifer tarandus tarandus) calves in winter to investigate rumen function and digestion. Three calves were given S with 18.5% dry matter (DM), three were given SM (21.9% DM) and three were given H (85.0% DM). The content of water soluble carbohydrates (in % of DM) was 8.2% in S, 16.0% in SM and 8.5% in H. Median (range) daily DM food intake per kg BM was 12.9 (9-2-14.4) g in calves fed S, 19.0 (19-0-21.9) g in calves fed SM and 21.0 (19.2&not;21.1) g in calves fed H. In vivo digestion of S and SM DM ranged from 78.5-83.1% compared to only 69-9-72.9% in calves fed H. In vitro DM digestion (IVDMD) of cellulose (median) incubated for 48 hours in rumen fluid was, however, significantly (F = 0.05) lower in calves fed S (24.4%) compared to calves fed SM (42.2%). Median IVDMD of cellulose (48 hours) in calves fed H was 36.4%. Total concentration of VFA (range) in the rumen fluid from reindeer fed H (99.7-113.6 mM) and was significantly (P<0.05) higher compared to animals fed S (57.7-85.9 mM) or SM (51.4-72.0 mM). Likewise, the pH of the rumen fluid (range) was significantly (P<0.05) lower in reindeer fed H (6.40-6.78) compared to animals fed S (6.97-7.30) or SM (6.79-7.27). Based on this study it is concluded that leafy timothy preserved as hay seems to be more suitable as emergency feed compared to silage. Supplementation of molasses to silage seems to stimulate food intake and ruminal cellulose digestion in reindeer. The lower intake of S compared to SM or H by reindeer may be explained by ruminal energy deficiency

The bacterial population adherent to plant particles in the rumen of reindeer fed lichen, timothy hay or silage

“…Grazers like cattle are known to have a higher DM intake of hay compared to silage prepared from the same crop (Campling, 1966;Uden, 1984). Recently this has also been demonstrated for reindeer (Moen et al, 1998;Table 4). Total concentrations of VFA in the rumen fluid was significantly lower and ruminal pH significantly higher in reindeer fed silage compared to hay, indicating a higher fermentation activity in the rumen of reindeer fed hay (Moen et al, 1998;Table 4).…”

“…Recently this has also been demonstrated for reindeer (Moen et al, 1998;Table 4). Total concentrations of VFA in the rumen fluid was significantly lower and ruminal pH significantly higher in reindeer fed silage compared to hay, indicating a higher fermentation activity in the rumen of reindeer fed hay (Moen et al, 1998;Table 4). Although the DM intake of hay is considerably higher than that of silage, this does not seem to have effected the rumen size of the animals fed the two different diets (Moen et al, 1998;Table 4).…”

“…Three of the calves were given ad lib. access to lichen (47 days), and compared with three calves fed regrowth timothy with 79% leaves preserved as hay (50 days) and three calves fed regrowth timothy from the same crop, but preserved as silage (50 days) (Øksendal, 1994;Moen et al, 1998). The chemical composition of the diets are presented in Table 1.…”

“…M 0262; Sigma) to detach the adherent bacteria from the food particles (Kudo et al, 1987). The solution with the rumen solids were homogenised Data from Moen et al (1998). ' Crude protein = total nitrogen x 6.25. in cortex tubes using a Polytron PT 10 OD homogenizer (Kinematica, GMB, Luzern, Schweiz) for 30-60 sec at a speed setting of 2.…”

“…In winter, crusts of snow and ice often cover the pasture, exposing the reindeer for periods of starvation, during which supplementary feeding can prevent loss of animals. Different qualities of grass silage have been evaluated as food for reindeer Olsen et al, 1995;Aagnes et al, 1996;Moen et al 1998), revealing pronounced morphophysiological limitations towards digestion of fibrous timothy (Phleurn pra tense) silage (Aagnes et al, 1996). Reindeet fed leaf rich silage made of Phleurn pratense, Agrostis tenuis and Poa spp., demonstrated low in vivo apparent digestibility coefficients (62-66%) and in vitro dry matter digestibility (IVDMD) of the silage (only 67-71% after 72 h incubation in rumen fluid), with correspondingly low ruminal VFA concentrations (38-53 mM) and high pH (6.95-7.17), indicating a limitation in the ability of the reindeer and its microbiota to utilise this grass silage .…”