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

This study aimed at testing the effects of three different formulations of feed supplements based on three different combinations of plant derived alkaloids, prebiotics, tannins, vitamins and minerals on rumen fermentation and the microbiome in vitro. A Rusitec experiment was conducted in 2 identical runs using a complete randomized design with 3 replicates per treatment resulting in total of 6 treatment combinations (n = 6). Each run lasted 12 d with sampling occurring in the last 5 d.

Bioavailability of Quercetin from Onion Extracts after Intraruminal Application in Cows.

The aim of the present study was to investigate the bioavailability of quercetin from onion bulb (OB) and onion skin (OS) extracts in ruminants. Three non-lactating cows equipped with a permanent rumen fistula intraruminally received equimolar amounts of quercetin as either aglycone, rutin, or OB or OS extract, respectively, at a dose of 50 mg of quercetin equivalents/kg of body weight. Blood samples were drawn before and frequently within the 24 h period after application of the respective substance.

Systemic Absorption of Catechins after Intraruminal or Intraduodenal Application of a Green Tea Extract in Cows.

Green tea catechins have various potential health benefits in humans including anti-inflammatory, anti-oxidative and hepato-protective effects. If present in the circulation, they might have similar effects in ruminants, which are exposed to oxidative stress and fatty liver disease such as dairy cows during the periparturient phase. However, the bioavailability of a substance is a prerequisite for any post absorptive effect in vivo.