Effect of a saponin-based surfactant and aging time on ruminal degradability of flaked corn grain dry matter and starch1

Abstract

The objectives of this study were to investigate the effect of a saponin-based surfactant, Grain Prep surfactant (GP), and hot flake aging time on starch characteristics and ruminal DM and starch degradability of steam-flaked corn grain. In 2 experiments, the moisture content of incoming corn was automatically adjusted using the Grain Prep Auto Delivery System to 19.8% (Exp. 1) and 18.5% (Exp. 2). The application rate of GP was 22 mg/kg (as-is basis). Control corn was treated with water alone. Processed corn in Exp. 2 was stored in insulated containers for 0, 4, 8, or 16 h. Flaked corn samples were incubated in the rumen of lactating dairy cows for 0, 2, 4, 6, 16, or 24 h. In Exp. 1, GP increased, compared with the control, the soluble fraction and effective degradability (ED) of DM by 17.2 and 8.6%, respectively. The ED of cornstarch was increased by 6.7%. In Exp. 2, the concentration of soluble DM and starch were increased by GP by 15 and 24% compared with the control. The ED of DM and starch were also increased by 3 and 4%, respectively. No differences in gelatinization temperatures were observed due to treatment, except that GP-treated grain had a slightly greater mean gelatinization enthalpy in Exp. 2. In a pilot study, DM degradability parameters were not affected by germination of the corn kernels. Aging of the hot flakes for up to 16 h resulted in a quadratic decrease in DM and starch ruminal degradability. The aging process affected starch gelatinization enthalpy values of flaked grain in a manner opposite to that observed for ruminal DM and starch degradation. This phenomenon was most likely explained by increased starch intramolecular associations or crystallinity associated with starch annealing, or both. This study confirmed our previous observations that Grain Prep surfactant increases flaked corn DM and starch degradability in the rumen. Because the rate of degradation was not affected by the surfactant, the increase in degradability was attributed mainly to increases in DM and starch solubility.

Saponin‐Based Surfactants

“…This phenomenon is most likely explained by increased starch intramolecular associations or crystallinity associated with starch annealing, or both. Because the rate of degradation was not affected by the surfactant, the increase in degradability was attributed mainly to increases in dry matter and starch solubility [16].…”

Degradability and gas production of diets enriched with additives in cattle or sheep inoculum

“…This result agrees with the descriptions of the Cong et al (2009), who observed an increase in IVDMD using three different surfactants. Hristov et al (2007) also reported increased in situ degradability of starch and DM with the addition of a surfactant to the diet.…”

Physicochemical Changes of Heat-Treated Corn Grain Used in Ruminant Nutrition

“…The various processing treatments of animal feeds influence the rumen fermentation characteristics of grain starch, which in turn affect animal performance. Based on a review of the available literature, the most commonly studied treatments of corn used in ruminant nutrition are grinding, dry rolling, steam rolling, and steam flaking [ 4 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Studies covering pelleting [ 26 , 27 ], extrusion [ 24 , 28 , 29 , 30 ], and expansion [ 31 ] are available but to a much lesser extent than the above-mentioned treatments.…”