Fatty acid profiles of some insect oils and their effects on in vitro bovine rumen fermentation and methanogenesis

In vitro supplementation of 0.05% [on a substrate basis (wt/wt)] - but not of 0.01% - of 9,10-Anthraquinone (AQ) inhibited rumen methanogenesis, reduced total volatile fatty acid (VFA) concentrations and molar proportions of acetate (Acet), increased proportions of propionate (Prop) and butyrate (But) and resulted sometimes in H2 accumulation (Garcia-Lopez et al., 1996). In vivo administration of high amounts of AQ [5% on a substrate basis (wt/wt)] to lambs depressed CH4 and increased H2 concentrations in ruminal gases during the complete 19 days of administration, whereas original concentrations were re-installed within 6 days after the removal of AQ from the diet (Kung et al., 1996). In this experiment we aimed to study the dose effect of AQ on in vitro rumen fermentation and modifications to rumen fermentation when administering 0.05% of AQ in vivo.

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Fatty acid profiles of typical dietary lipids after gastrointestinal digestion and absorbtion: A combination study between in-vitro and in-vivo

Food Chemistry ◽

10.1016/j.foodchem.2018.12.032 ◽

2019 ◽

Vol 280 ◽

pp. 34-44 ◽

Cited By ~ 12

Author(s):

Zhan Ye ◽

Ruizhi Li ◽

Chen Cao ◽

Yong-Jiang Xu ◽

Peirang Cao ◽

...

Keyword(s):

Fatty Acid ◽

Dietary Lipids ◽

Fatty Acid Profiles ◽

Gastrointestinal Digestion ◽

Combination Study

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Effects of replacing starch with three sugars in a concentrate and forage diet on in vitro rumen fermentation, fatty acid composition and related bacteria

Animal Production Science ◽

10.1071/an18287 ◽

2020 ◽

Vol 60 (9) ◽

pp. 1173

Author(s):

X. Q. Sun ◽

Y. P. Wang ◽

R. Y. Wei ◽

B. Chen ◽

X. Zhao

Keyword(s):

Fatty Acid ◽

Milk Fat ◽

Volatile Fatty Acids ◽

Corn Starch ◽

Underlying Mechanism ◽

Rumen Fermentation ◽

Dose Effect ◽

Milk Fat Depression ◽

In Vitro Rumen Fermentation

Context Replacing starch with sugar could maintain dietary energy density with reduced risks of rumen acidosis and milk fat depression, but the underlying mechanism is not well understood, and the effects of sugar feeding might vary among sugars. Aims Objectives of the present study were to evaluate the effects of replacing corn starch in a diet containing 40:60 forage-to-concentrate ratio (control) with 3%, 6% and 9% of sucrose, fructose and lactose on in vitro rumen fermentation, fatty acid (FA) composition and populations of bacteria involved in the production of trans-11 and trans-10 FA. Methods A 3 × 3 + 1 (control) factorial experimental design was used, and the pH, concentrations of volatile fatty acids (VFA) and ammonia-N, profiles of FA and the relative abundance of four trans-11-producing bacteria and two trans-10 FA-producing bacteria were measured after a 6-h incubation. Key results Replacing dietary corn starch with sucrose, fructose and lactose neither altered the concentration of total VFA after 6-h fermentation, nor decreased the pH, except for substitution with 9% sucrose. Increased butyrate proportions and decreased branched-chain VFA proportions were the common effects in sugar treatments, but the proportions of acetate and propionate varied among sugars. Lactose inclusion in the diet led to a higher pH, greater acetate and butyrate concentrations, and lower propionate concentrations than did sucrose inclusion. Sugar substitution decreased the concentrations of C18:1 trans-4 and most C18:2 isomers, but did not influence the major isomers related to trans-11 and trans-10 biohydrogenation pathways. Abundance of the four measured trans-11 FA-producing bacteria was increased by sugars, with sucrose showing a greater influence than did fructose and lactose. As to trans-10 FA-producing bacteria, only Megasphaera elsdenii populations were decreased by 3% and 6% fructose inclusion compared with the control. Dose-effect varied among sugars and the parameters measured, with sucrose having the most obvious dose effect among the three sugars; however, fructose affected mainly fermentation parameters, while lactose affected mainly C18 FA profiles. Conclusions Replacing corn starch in a high-concentrate diet with up to 9% of sucrose, fructose and lactose differentially affected rumen fermentation and rumen FA metabolism, by influencing the abundance of rumen bacteria involved in rumen FA biohydrogenation. Implications Lactose may be more efficient in increasing milk fat than are sucrose and fructose, and dose effect should be considered in the utilisation of sucrose.

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Fetal lipoproteins and placental release of esterified lipids

Reproduction Fertility and Development ◽

10.1071/rd9960457 ◽

1996 ◽

Vol 8 (3) ◽

pp. 457 ◽

Cited By ~ 1

Author(s):

JP Stammers ◽

TJ Stephenson ◽

JA Colley ◽

D Hull

Keyword(s):

Fatty Acid ◽

Free Fatty Acid ◽

Late Gestation ◽

Free Fatty Acid Concentration ◽

Fatty Acid Profiles ◽

Rabbit Plasma ◽

Albumin Solution ◽

Series Of Experiments

An in vitro incubation technique was used to examine the release of lipids from the rabbit placenta. Free fatty acid, but not phospholipid or triacylglycerol, was released into the incubation media. In a second series of experiments, the addition of lipids to the umbilical circulation was studied in situ in the placenta of anaesthetized rabbits at late gestation. Each placenta was perfused from the fetal side in turn with two different perfusate solutions, either 4% bovine albumin solution or rabbit plasma. The rabbit plasma contained the appropriate carriers (lipoproteins) for esterified lipids, whereas the 4% albumin solution did not. The effluent perfusates were remarkably similar in free fatty acid concentration and composition, which closely matched the maternal free fatty acid profiles. The concentrations and fatty acid composition of the perfusate triacylglycerol and phospholipid fractions were unchanged by passage through the placenta, whether perfused with 4% albumin or with rabbit plasma. With this system, no evidence could be found for the addition of esterified lipids to the umbilical circulation in the rabbit despite the provision of appropriate carriers on the fetal side of the placenta.

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