Thermal decomposition, chemical composition, in vitro digestibility and gas production and in situ degradability of oilseed residues from the biofuel industry

Abstract

Thermal analysis could rapidly and easily predict nutritional value of ruminant feeds. The hypothesis is that crambe meal (CM) has a quality similar to that of soybean meal (SM), and the objective of this study was to determine the nutritional characteristics of CM and compare them to those of SM. CM had greater concentrations of phytic acid (26.3 vs. 16.0 g/kg) and phenol compounds (615 vs. 393 mg gallic acid (GAE)/kg) than SM. In vitro dry matter (DM) digestibility was lower for CM than SM (752 vs. 975 g/kg DM). Cumulative in vitro gas production at 48 h of incubation (14.1 vs. 19.4 mL/100 mg substrate DM), and energy release (4.5 vs. 5.7 kJ/g substrate DM) were lower for CM than SM. CM had a higher concentration of low digestible fiber, hence degradability of DM was lower and the proportion of indigestible fraction was greater for CM than SM. High concentrations of indigestible compounds were likely responsible for lower gas production of CM compared to SM. These results suggest CM quality is lower than that of SM and that thermal analysis is a useful tool to precisely determine the nutritive value of oilseed residues.

In Vitro Digestibility and Models of Cumulative Gas Production of Forage-Free Diet

“…The in vitro cumulative gas production technique is frequently used to assess concentrate [13,14] and roughage quality [15][16][17]. By the measurement of in vitro gas accumulation, it is possible to know about the kinetics of feed digestion in rumen fluid.…”

“…Nonlinear models, especially the Gompertz, Brody, Orskov, and Dual-pool Logistic models, are used to fit the kinetics of in vitro gas production. The Dual-pool Logistic model [19] has been commonly used [13][14][15][16][17]20,21]. However, an important step in this evaluation process is the choice of the model to adjust the fermentation parameters according to the studied food.…”

Kinetics of In Vitro Gas Production and Fitting Mathematical Models of Corn Silage

“…This variety of mathematical models is still used to fit in vitro gas production of cattle feeds, additives or diverse conditions due to that its complexity of biological factors fit perfectly in one single model for posterior statistical analysis of the studied treatments. However, the Dual-pool Logistic model [8] has been widely used to fit the in vitro gas production of feedstuffs and diets for ruminants [9][10][11][12][13]. Nevertheless, it should be noted that a single model should not be used for all types of feed; rather, it is essential that different models be adjusted for each nutritional situation [14].…”