Mangosteen peel can reduce methane production and rumen biohydrogenation in vitro

Mangosteen peel (MP), an agricultural by-product of tropical countries, has been reported to contain condensed tannins and saponins, which can affect rumen microbes to reduce enteric methane emission. In the present study, the effects of mangosteen peel on in vitro ruminal fermentation, gas production, methane production, fatty acid biohydrogenation, and microbial population were investigated. Results showed that MP at medium and high levels (25 % and 50 % replacing alfalfa) were able to reduce (P <0.05) in vitro methane production without affecting volatile fatty acid (VFA) production and the pH of the substrate. The lowering effect of MP on methane production was because of suppression of the rumen microbial populations, especially total protozoa and total methanogens. MP at the higher level (50%) reduced (P <0.05) the amounts of biohydrogenation for linoleic acid (C18:2n-6), α-linolenic acid (C18:3n-3) and the total C18 unsaturated fatty acids (UFA) owing to the reduction of the Butyrivibrio fibrisolvens population, that is, the most important rumen microorganism involved in the biohydrogenation process. In conclusion, mangosteen peel has potential to be used in ruminant livestock feeds, with the advantage of reducing ruminal methane production and biohydrogenation, without adverse effects on ruminal pH and VFA production.Keywords: agricultural by-product, saponins, condensed tannins, gas production, volatile fatty acid, microbial quantificatio

Profiling of rumen fermentation, microbial population and digestibility in goats fed with dietary oils containing different fatty acids

Background: The effects of the dietary oils with differing fatty acid profiles on rumen fermentation, microbial population, and digestibility in goats were investigated. In Experiment I, rumen microbial population and fermentation profiles were evaluated on 16 fistulated male goats that were randomly assigned to four treatment groups: i) control (CNT), ii) olive oil (OL), iii) palm olein oil (PO), and iv) sunflower oil (SF). In Experiment II, another group of 16 male goats was randomly assigned to the same dietary treatments for digestibility determination. Results: Rumen ammonia concentration was higher in CNT group compared to treatment groups receiving dietary oils. The total VFA and acetate concentration were higher in SF and OL groups, which showed that they were significantly affected by the dietary treatments. There were no differences in total microbial population. However, fibre degrading bacteria populations were affected by the interaction between treatment and day of sampling. Significant differences were observed in apparent digestibility of crude protein and ether extract of treatment groups containing dietary oils compared to the control group. Conclusions: This study demonstrated that supplementation of different dietary oils containing different fatty acid profiles improved rumen fermentation by reducing ammonia concentration and increasing total VFA concentration, altering fibre degrading bacteria population, and improving apparent digestibility of crude protein and ether extract

Pomegranate seed oil rich in conjugated linolenic acids reduces in vitro methane production

The objective of this study was to determine the effect of pomegranate (Punica granatum L.) seed oil (PSO) on gas and methane (CH4) production, ruminal fermentation and microbial populations under in vitro conditions. Three treatments consisting of a control diet containing 10 mg tallow (CON); the control diet with 5 mg PSO + 5 mg tallow (MPSO) and the control diet containing 10 mg PSO (HPSO) were compared. Ten mg of the experimental fat/oil samples were inserted into a gas-tight 100 mL plastic syringe containing 30 mL of an incubation inoculum and 250 mg of a basic substrate of a hay/concentrate (1/1, w/w) mixture. In vitro gas production was recorded over 0, 2, 4, 6, 8, 10, 12 and 24 h of incubation. After 24 hours, incubation was stopped, and methane production, pH, volatile fatty acids (VFAs) and microbial counts were measured in the inoculant. Gas production at 4, 6, 8, 10, 12 and 24 h incubation, metabolizable energy and in vitro organic matter disappearance increased linearly and quadratically as level of PSO increased. Furthermore, the 10 mg PSO (HPSO) decreased CH4 production by 21.0% compared with the control (CON) group. There were no significant differences in total and individual VFA concentrations between different levels of PSO, except for butyric acid. After 24 h of incubation, methanogenesis decreased in the HPSO compared with the MPSO and CON treatments. In addition, total bacteria and protozoa counts increased with rising PSO levels, while population methanogenesis declined significantly. These results suggested that PSO could reduce methane emissions, which might be beneficial to nutrient utilization and growth in ruminants

Safety Assessment of Two New Lactobacillus Strains as Probiotic for Human Using a Rat Model

Two previously isolated Lactobacillus strains (L. fermentum HM3 from human milk and L. buchneri FD2 from fermented dates), intended as probiotic for human, were assessed for their safety using acute and subacute oral toxicity tests in rats. In addition, their effects on cecal microflora and harmful bacterial enzymes (β-glucuronidase and β-glucosidase) of the tested animals were also determined. The results showed that L. buchneri FD2, L. fermentum HM3, or a mixture of them were safe up to a level of 1010 CFU/kg BW/day in a 14-day or 28-day treatment period. Both strains were well tolerated and there were no observed adverse effects on growth, feed consumption, cellular blood components and vital organs of the treated animals. The Lactobacillus strains were also able to reduce harmful intestinal bacterial enzymes, and decrease pathogenic bacterial populations while increasing beneficial bacterial populations. These results suggest that the two Lactobacillus strains are safe and could be potential probiotic for human