Effects of the supplementation of plant-based formulations on microbial fermentation and predicted metabolic function in vitro

Isoquinoline Alkaloids and the Ionophore Monensin Supplemented Alone or Combined on Ruminal Fermentation and Nutrient Digestibility in Steers Fed a High-Energy Diet

“…Although IQA increased ruminal microbial efficiency, N efficiency and postruminal N digestion, it did not affect (P>0.10) ruminal, postruminal and total tract digestion of OM, starch and NDF. The absence of IQA effects on digestion of OM, starch and NDF are consistent with those obtained in previous studies performed in vivo (Aguilar-Hernández et al, 2016) and in vitro (Rusitec experiment; Petri et al, 2019).…”

“…The absence of effects of IQA on ruminal pH and total VFA production are consistent with lack of treatment effect on ruminal OM digestion. Similar findings have been reported for steers fed both medium energy diets (Petri et al, 2019) and high energy diets (Aguilar-Hernández et al, 2016;Zhang et al, 2019). In vitro studies of Smink and van der Kolk ( 2004) also showed increased acetate: Propionate molar ratio without effect on total VFA production.…”

“…Aguilar-Hernández et al (2016) observed that in steers fed a diet similar that of the present study, 206 supplementation with 16.8 mg IQA/kg diet DM decreased ruminal ammonia N concentration; presumably due to decreased proteolysis and deamination of amino acids (Drsata et al, 1996). More recently, Petri et al (2019) likewise observed decreased amino acids metabolism in IQA supplemented treatments. They noted that predicted amino acid metabolism pathways were down-regulated in all IQA supplemented groups in comparison to the control group, a key mode of action for these IQA supplementation in regard to improving ruminal amino acid bypass.…”

“…Earlier reports indicate that MON decrease ruminal concentration of microorganisms with high proteolytic activity and it may have direct effect on protease and deaminase enzymes as well (Bergen and Bates, 1984;Russell and Strobel, 1989). On the other hand, IQA could modulate metabolism of rumen microbes with minor changes on rumen microbial population and species diversity (Petri et al, 2019). The effects of both additives alone, decrease the ruminal degradation of feed N; however based on the duodenal flows of NAN, ruminal scape feed N and microbial N with the combination, apparently the effects of each additive are negatively affected.…”

“…Whereas protozoal counts for control and MON plus IQA were not different. Likewise, Petri et al (2019) using a rumen simulation technique (Rusitec) noted that IQA supplementation decreased ruminal protozoa population. Sanguinarine and chelerythrine, principal compounds on IQA source used here, have a significant dose-dependent antibacterial activity (since 16 µg/mL) against Gram-positive and Gram-negative bacteria when tested in vitro (Opletal et al, 2014).…”