Effects of including saponins (Micro-Aid®) on intake, rumen fermentation and digestibility in steers fed low-quality prairie hay

Abstract

Sixteen ruminally cannulated crossbred steers (529 ± 45 kg initial body weight, BW) were used to evaluate in situ dry matter (DM), neutral detergent fiber (aNDF), and N degradation characteristics of low-quality prairie hay, blood urea-N (BUN) and rumen fermentation parameters in steers provided a protein supplement with or without Micro-Aid ® (MA; plant derived saponin). Steers were allowed ad libitum access to chopped prairie hay (49 g crude protein (CP)/kg DM and 738 g aNDF/kg DM) and randomly assigned to one of four treatments: (1) no supplement (C), (2) cottonseed meal and wheat middlings: 920 g DM/d (PC; positive control), (3) MA added to PC to supply 1 g MA/d (MA1), and (4) MA added to PC to supply 2 g MA/d (MA2). Steers were individually supplemented 920 g DM once daily at 08:00 along with a vitamin and mineral mix to ensure requirements were met. Orthogonal contrasts were used to determine the effects of protein supplementation, addition of MA and level of MA inclusion. During in situ phase, forage samples were incubated for a 96 h period. Protein supplementation increased DM intake (DMI), particulate passage rate (Kp), and rumen digestibility of DM and NDF (P < 0.001), but there was no effect on rumen N degradability. The inclusion of MA did not impact DMI in either phase. Compared to PC, MA decreased K p (27.8 and 22.7 g DM/kg/h, respectively; P = 0.02), resulting in an increase in rumen aNDF and DM digestibility (P < 0.001). However, there was no influence of MA on apparent total tract digestibility in the metabolism phase. Rumen protozoa concentrations were suppressed (P = 0.01) with MA inclusion while lactate concentrations and microbial crude protein (MCP) flow to the small intestine were increased (P = 0.05). There was no impact on BUN, rumen ammonia, pH, volatile fatty acid (VFA) concentrations or N balance for MA compared to PC diets. Supplementation improved N balance, MCP synthesis and increased total concentrations of VFA and independent acetate and propionate concentrations. In conclusion, including MA in protein supplements increased rumen DM and a NDF digestibility of forage, reduced protozoa concentrations and increased daily outflow of MCP. This is indicative of increased rumen fermentation rate and may ultimately impact animal performance via increased energy and amino acid supply to the small intestine. However, more research is needed to validate this potential impact on animal performance.

Effects of garlic oil, nitrate, saponin and their combinations supplemented to different substrates on in vitro fermentation, ruminal methanogenesis, and abundance and diversity of microbial populations

“…It is well‐established that saponins decrease protozoal numbers in the rumen (Patra and Saxena ; McMurphy et al . ; Manatbay et al . ) by interacting with the cholesterol in their cell membranes thereby destructing protozoal cells (Patra and Saxena ).…”

<b><i>In vitro</i> degradation and gas production of glycerin generated in the biodiesel production chain

“…The addition of glycerin produced different results; for example, the concentration of ammonia nitrogen in the corn silage was reduced considerably with increasing levels of glycerin. The reduction in the concentration of ammonia nitrogen with increasing levels of glycerin can be explained by the increase in ruminal availability of energy, allowing the greater use of ammonia for microbial growth (McMurphy et al, 2014).…”

Productive and physiological responses of feeder cattle supplemented withYucca schidigeraextract during feedlot receiving1

“…According to the manufacturer (DPI Global), MA is a plant-derived feed additive for use in animal feeds, manufactured from a purified extract Y. schidigera that grows in the southwest United States and Mexico, and contains 97% DM and 181.6 g of saponin per kilogram of DM (Singer et al, 2008). The administration rates of MA herein were according to manufacturer's recommendations and previous research with growing beef cattle (McMurphy et al, 2014a(McMurphy et al, ,2014b From days 0 to 59, cattle had free-choice access to water and TMR (Table 1), which was offered twice daily (0800 and 1300 hours). The TMR was offered in a manner to yield 15% (as-fed basis) orts from the previous feeding, via a vertical feed mixer (NDEco S600; New Direction Equipment; Sioux Falls, SD) into concrete feed bunks (7.5 m of linear bunk space per pen).…”

“…Supplementing MA to forage-fed beef steers at 1 or 2 g/d (as-fed basis) improved in situ ruminal forage digestibility (McMurphy et al, 2014a) but not ADG ( McMurphy et al, 2014b), whereas MA supplementation at 2 g/d increased microbial N flow (McMurphy et al, 2014a). However, the effects of MA supplementation on performance or immune parameters in receiving cattle still warrant investigation.…”

“…This outcome should be primarily attributed to increased G:F feed efficiency in M2 cattle, given that TMR intake, incidence of BRD signs, and all physiological responses did not differ among treatment groups. McMurphy et al (2014a) reported that MA supplementation at 1 and 2 g/day (as-fed basis) improved in situ rumen DM and neutral detergent fiber digestibility in beef steers, without impacting total feed intake. Authors associated these outcomes with decreased rumen particulate passage rate in MA-supplemented cattle, as saponins from Y. schidigera have foam-forming characteristics that may increase rumen fluid viscosity (Cheeke, 2000).…”