Comparative Digestion, Rumen Fermentation and Kinetics of Forage Diets by Steers and Wethers3

Abstract

Four rumen fistulated wether and beef steers were used to evaluate differences in dry matter digestibility (DMD) between cattle and sheep. They were fed either perennial ryegrass or switchgrass hay at an ad libitum or restricted level for four experimental periods. Significant ruminant species X forage and ruminant species X level of intake (P less than .05) interactions were observed for digestible dry matter. The steers digested the switchgrass 7 percentage units greater than the wethers while ryegrass was digested equally. Digestibility differences between the steers and wethers were 6 percentage units at the ad libitum level of intake and 1 unit at the restricted level of intake. Crude protein digestibility tended to be greater (P less than .10) for sheep with a 7 unit difference for switchgrass and a 3 unit difference for ryegrass. The mean ruminal solids retention time of the digesta was approximately (P less than .01) 50% greater (26.0 vs 17.4 h) in cattle, with no difference in ruminal liquid dilution rate (LD) between animal species. Total ruminal volatile fatty acid concentration differed (P less than .01) with level of intake; however, no influence due to intake on the molar proportion of acetate (P greater than .10) or propionate (P greater than .10) was evident in spite of a difference (P less than .01) in LD. Rumen pH (P less than .05) and osmolality (P less than .01) were affected by both level of intake and forage, with the ryegrass and high level of intake decreasing pH and increasing osmolality.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of ensiling maize and sample conditioning on in situ rumen degradation of dry matter, starch and fibre

“…The in situ method using undried and unground samples incubated in bigger (10 × 20 cm) bags has been employed by some teams (Prigge et al, 1984;Nocek, 1988;Andrae et al, 2001) but was not applied here as it limits the number of bags simultaneously present in the rumen.…”

A mechanistic model for predicting the nutrient requirements and feed biological values for sheep1

“…The coefficients for digestibility for DM, OM, NDF, and CP reported in 13 publications (Hogan and Weston, 1967;Robles et al, 1981;Prigge et al, 1984;Aitchison et al, 1986;Caton et al, 1988;Colucci et al, 1989;Wales et al, 1990;Di Francia et al, 1994;Torrent et al, 1994;Garcés-Yépez et al, 1997;Ranilla et al, 1998;Mulligan et al, 2001;Molina et al, 2001) were compared with the values estimated by the CNCPS-S. The evaluations were carried out using the information reported in the publications on FBW, feed intake, and composition as inputs in the CNCPS-S.…”

The dissociation of the fluid and particle phase in the forestomach as a physiological characteristic of large grazing ruminants: an evaluation of available, comparable ruminant passage data

“…(1984), Prigge et al (1984), Dixon and Milligan (1985), McCollum and Galyean (1985), Merchen et al (1986), Funk et al (1987, Krysl et al (1987), Jacques et al (1989, Renecker and Hudson (1990), Tatman et al (1991), Arthun et al (1992), Spalinger et al (1993), Robbins et al (1995, citing Spalinger and Murden, unpublished article, read from graph), Kaske and Groth (1997), Behrend (2000), and the original dataset from Lechner-Doll et al (1990).…”