Effects of natural rainfall and spontaneous heating on voluntary intake, digestibility, in situ disappearance kinetics, passage kinetics, and ruminal fermentation characteristics of tall fescue hay fed to growing steers

Turner, James; Coblentz, W.K.; Coffey, Ken; Rhein, R. T.; McGinley, B. C.; Galdámez-Cabrera, N.W; Rosenkrans, C. F.; Johnson, Z. B.; Kellogg, D. W.; Skinner, J. J.

doi:10.1016/j.anifeedsci.2004.05.004

Cited by 8 publications

(10 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For bermudagrass hays accumulating 5 to 401 HDD during storage based on a 35°C threshold, NDF digestibility declined linearly when hays were offered to growing wethers (McBeth et al, 2001); however, this relationship was characterized by a relatively limited range (60.4 to 66.5%) and a relatively poor coefficient of determination (r 2 = 0.30). In contrast, Turner et al (2004) reported a tendency for increased in vivo digestibilities of NDF in growing steers offered tall fescue [Lolium arundinaceum (Schreb.) Darbysh] hays that heated modestly during storage.…”

Section: Regressions Of Changes In Concentrations Of Fiber Componentsmentioning

confidence: 92%

“…Koel.] (Ogden et al, 2005), 0.9 to 5.9% for headed tall fescue hays (Turner et al, 2004), and 3.1 to 4.0% for heated bermudagrass hays (McBeth et al, 2003). Often, it has been suggested that these small percentages of the total NDF pool are associated with direct losses of small particles from the Dacron bags during rinsing, which is a criticism of the in situ procedure generally (Broderick, 1994;Broderick and Cochran, 2000).…”

Section: In Situ Disappearance Kinetics Of Ndfmentioning

confidence: 99%

“…Generally, these results support past work. McBeth et al (2003) reported that K d for NDF disappearance declined by 23% for heated bermudagrass hays, but Turner et al (2004) reported no change in ruminal rates of NDF disappearance for heated tall fescue hays that reached a MAX of 50°C. Effective Degradability.…”

Section: In Situ Disappearance Kinetics Of Ndfmentioning

confidence: 99%

“…Although the threshold moisture for acceptable storage for small (~45-kg) rectangular bales is approximately 20% (Collins et al, 1987), thresholds for larger hay packages are assumed generally to be lower, but they vary with the size and density of bales, as well as other factors. In addition to oxidation of nonstructural carbohydrates (Coblentz et al, 1997a), the phenomenon of spontaneous heating is associated with mold growth (Roberts, 1995), deleterious changes in forage nutritive value (Collins et al, 1987;Coblentz et al, 1996Coblentz et al, , 2000Turner et al, 2002), alteration of ruminal disappearance kinetics of N, fiber, and DM (Coblentz et al, 1997b;McBeth et al, 2003;Turner et al, 2004), and less desirable measures of in vivo disappearance of DM (Montgomery et al, 1986;McBeth et al, 2001;Turner et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

“…In addition, it is frequently assumed that the digestibility of forage fiber is reduced by spontaneous heating, but support for this premise based on in vivo or other assessments is limited. Several studies have reported relationships between in vivo NDF digestibility and heating that were mildly negative (McBeth et al, 2001), inconclusive (Turner et al, 2004), or even positive when steamtreated (100 to 110°C for 0.75 h) alfalfa-hay-based diets were offered to lactating dairy cows (Broderick et al, 1993). Using in situ procedures, rates of ruminal NDF disappearance (K d ) for heated bermudagrass [Cynodon dactylon (Pers.)…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Effects of spontaneous heating on fiber composition, fiber digestibility, and in situ disappearance kinetics of neutral detergent fiber for alfalfa-orchardgrass hays

Coblentz

Hoffman

2009

Journal of Dairy Science

View full text Add to dashboard Cite

"Effects of spontaneous heating on fiber composition, fiber digestibility, and in situ disappearance kinetics of neutral detergent fiber for alfalfa-orchardgrass hays" (2009 aBStraCt During 2006 and 2007, forages from 3 individual hay harvests were utilized to assess the effects of spontaneous heating on concentrations of fiber components, 48-h neutral detergent fiber (NDF) digestibility (NDFD), and in situ disappearance kinetics of NDF for large-round bales of mixed alfalfa (Medicago sativa L.) and orchardgrass (Dactylis glomerata L.). Over the 3 harvests, 96 large-round bales were made at preset bale diameters of 0.9, 1.2, or 1.5 m, and at moisture concentrations ranging from 9.3 to 46.6%. Internal bale temperatures were monitored daily during an outdoor storage period, reaching maxima (MAX) of 77.2°C and 1,997 heating degree days >30°C (HDD) for one specific combination of bale moisture, bale diameter, and harvest. Concentrations of all fiber components (NDF, acid detergent fiber, hemicellulose, cellulose, and lignin) increased in response to spontaneous heating during storage. Changes in concentrations of NDF during storage (poststorage -prestorage; ΔNDF) were regressed on HDD using a nonlinear regression model (R 2 = 0.848) that became asymptotic after ΔNDF increased by 8.6 percentage units. Although the specific regression model varied, changes (poststorage -prestorage) in concentrations of acid detergent fiber, cellulose, and lignin also increased in nonlinear relationships with HDD that exhibited relatively high coefficients of determination (R 2 = 0.710 to 0.885). Fiber digestibility, as determined by NDFD, was largely unaffected by heating characteristics except within bales incurring the most extreme levels of HDD or MAX. In situ assessment of ruminal NDF disappearance kinetics indicated that disappearance rate (K d ) declined by about 40% within the range of heating incurred over these hay harvests. The change in K d during storage (ΔK d ) was related closely to both HDD and MAX by nonlinear models exhibiting high R 2 statistics (0.907 and 0.883, respectively). However, there was no regression relationship between changes (poststorage -prestorage) in effective ruminal disappearance of NDF and spontaneous heating, regardless of which heating measure was used as the independent variable. The close regression relationship between ΔK d and measures of spontaneous heating indicates clearly that ruminal NDF disappearance was altered negatively by some direct or indirect aspect of spontaneous heating. However, it was equally apparent that these effects were offset by an expanding pool of dry matter recovered as potentially degradable NDF.

show abstract

Section: Regressions Of Changes In Concentrations Of Fiber Componentsmentioning

confidence: 92%