The effects of tannin-rich plants on parasitic nematodes in ruminants

Apart from the obvious role of plants in herbivore nutrition, they are also a rich source of bioactive products that can operate either to the benefit or the detriment of grazing animals. Here, we review the available evidence for the potential beneficial effects that plant-derived bioactive substances can have on gastrointestinal parasites. Tannin-rich plants have attracted most attention for their effect on internal nematodes in ruminants. These plants could act through direct antiparasitic activity but might also act indirectly by increasing host resistance. The effects vary with the species of plant, parasite and host. More research is required to understand better the mechanisms of action, and therefore make more pertinent use of these bioactive plants in livestock systems.

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Nutritional Influences on Skatole Formation and Skatole Metabolism in the Pig

Abstract

Skatole is a tryptophan (TRP) metabolite with fecal odor. Together with the testicular steroid androstenone it is regarded as a main determinant of boar taint, even if elevated concentrations of skatole occur occasionally in gilts and barrows. Skatole concentrations in adipose tissue result from a complex process, which includes the availability of TRP and the presence of specialized bacteria in the gut in need of TRP for energy production, as well as absorption, transport and accumulation of skatole in adipose tissue. Several steps of this process are influenced by diet and specific feed compounds. In the present paper the current knowledge about physiological mechanisms of skatole dynamics is summarized. Additionally mechanisms are discussed, by which effective feeding strategies and feed additives exert their influence in the prevention of high skatole concentrations in adipose pig tissue. It was concluded that the most effective measures are those which influence several steps of skatole formation. Despite the numerous studies carried out in the field of skatole physiology, interesting aspects still need clarification, such as the effect of adipose tissue turnover. Reliable control of skatole accretion in fat of boars is one of the main prerequisites for pork production with entire males.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4494329/

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The effects of condensed tannins from Dorycnium rectum on skatole and indole ruminal biogenesis for grazing sheep

AbstractSkatole and indole are flavour compounds formed in the rumen, which are key factors in the pastoral flavour of meat and milk products. A selection of indolic compounds has been screened for their potential to form skatole and indole on in vitro fermentation, with rumen inocula collected from New Zealand pasture-fed sheep. Typically, 8% (P < 0.005) of added tryptophan was converted to indole and 54% (P < 0.001) was converted to skatole via indole acetic acid (IAA). The addition to rumen inocula of a condensed tannin (CT) fraction isolated from the forage legume, Dorycnium rectum, reduced the conversion of plant protein to skatole and indole by 75% and specifically inhibited the transformation of IAA to skatole by 85% (P < 0.001). The conversion of tryptophan to indole or IAA was not affected by CTs. The inhibitory effect of CTs on the conversion of tryptophan to skatole was prevented by the addition of polyethylene glycol (PEG) to the rumen inocula prior to the addition of CTs, but not by the addition of PEG subsequent to CTs, demonstrating that interactions between CTs and microbes involved in skatole biosynthesis are not reversible by PEG. This study is the first to demonstrate that isolated CTs have an inhibitory effect on the conversion of protein to skatole and indole by rumen microbes, and that CTs specifically inhibit the transformation of IAA to skatole by rumen microbes.

The effects of condensed tannins from Dorycnium rectum on skatole and indole ruminal biogenesis for grazing sheep. Available from: https://www.researchgate.net/publication/248897639_The_effects_of_condensed_tannins_from_Dorycnium_rectum_on_skatole_and_indole_ruminal_biogenesis_for_grazing_sheep [accessed Jun 19, 2017].

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COMMISSION IMPLEMENTING REGULATION (EU) 2017/66 of 14 December 2016 concerning the authorisation of tannic acid as a feed additive for all animal species

COMMISSION IMPLEMENTING REGULATION (EU) 2017/66 of 14 December 2016
concerning the authorisation of tannic acid as a feed additive for all animal species
(Text with EEA relevance)

“…The European Food Safety Authority (‘the Authority’) concluded in its opinion of 11 September 2014 ( 3 ) that, under the proposed conditions of use in feed this substance does not have adverse effects on animal health, human health or the environment. The Authority further concluded that the function of tannic acid in feed is similar to that on food. The Authority has already concluded that for food tannic acid is efficacious, as it increases the food smell or palatability. Therefore, that conclusion can be extrapolated for feed.

(5) Restrictions and conditions should be provided for to allow better control. Since safety reasons do not require the setting of a maximum content and taking into account the re-evaluation performed by the Authority, a recommended content should be indicated on the label of the additive. Where such content is exceeded, certain information should be indicated on the label of premixtures, compound feeds and feed materials. ..”

http://doc.FeedAdd.com/17_0927_00_e.pdf

https://members.wto.org/crnattachments/2017/SPS/EEC/17_0927_00_e.pdf

 

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Application of Mössbauer spectroscopy to the study of tannins inhibition of iron and steel corrosion

Application of Mössbauer spectroscopy to the study of tannins inhibition of iron and steel corrosion
Authors: Jaén, Juan A.; de Obaldía, J.; Rodríguez, M. V.
Affiliation: AA(Depto. de Química Física, Universidad de Panamá, CITEN), AB(Escuela de Química, Facultad de Ciencias Naturales, Exactas y Tecnología, Universidad de Panamá), AC(Escuela de Química, Facultad de Ciencias Naturales, Exactas y Tecnología, Universidad de Panamá)
Publication: Hyperfine Interactions, Volume 202, Issue 1-3, pp. 25-38
Publication Date: 11/2011
Origin: SPRINGER
Keywords: Tannins, Corrosion inhibition, Mössbauer spectroscopy, Potentiodynamic polarization curves
Abstract Copyright: (c) 2011: Springer Science+Business Media B.V.
DOI: 10.1007/s10751-011-0337-1
Bibliographic Code: 2011HyInt.202…25J

Abstract

The inhibitory effect of tannins was investigated using, among others, potentiodynamic polarizations and Mössbauer spectroscopy. These techniques confirmed that the nature, pH and concentration of tannic solution are of upmost importance in the inhibitory properties of the solutions. It is observed that at low tannin concentration or pH, both, hydrolizable and condensed tannins, effectively inhibit iron corrosion, due to the redox properties of tannins. At pH ≈ 0, Mössbauer spectra of the frozen aqueous solutions of iron(III) with the tannin solutions showed that iron is in the form of a monomeric species [Fe(H2O)6]3 + , without coordination with the functional hydroxyl groups of the tannins. The suspended material consisted of amorphous ferric oxide and oxyhydroxides, though with quebracho tannin partly resulted in complex formation and in an iron (II) species from a redox process. Other tannins, such as chestnut hydrolysable tannins, do not complex iron at this low pH. Tannins react at high concentrations or pH (3 and 5) to form insoluble blue-black amorphous complexes of mono-and bis-type tannate complexes, with a relative amount of the bis-ferric tannate generally increasing with pH. Some Fe2 + in the form of hydrated polymeric ferrous tannate could be obtained. At pH 7, a partially hydrolyzed ferric tannate complex was also formed. The latter two phases do not provide corrosion protection. Tannin solutions at natural pH react with electrodeposited iron films (approx. 6 μm) to obtain products consisting only on the catecholate mono-complex of ferric tannate. Some aspects of the mechanism of tannins protection against corrosion are discussed.

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Studies on Emblica officinalis derived tannins for their immunostimulatory and protective activities against coccidiosis in industrial broiler chickens.

Abstract

The present study reports the effect of Emblica officinalis (EO) derived tannins on humoral immune responses and their protective efficacy against Eimeria infection in chickens. Tannins were extracted from EO and characterized by HPLC. EO derived tannins (EOT) and commercial tannins (CT) were orally administered in broiler chicks in graded doses for three consecutive days, that is, 5th-7th days of age. On day 14 after administration of tannins, humoral immune response was detected against sheep red blood cells (SRBCs) by haemagglutination assay. Protective efficacy of tannins was measured against coccidial infection, induced by Eimeria species. Results revealed higher geomean titers against SRBCs in chickens administered with EOT as compared to those administered with CT and control group. Mean oocysts per gram of droppings were significantly lower (P < 0.05) in EOT administered chickens as compared to control group. Lesion scoring also showed the lowest caecal and intestinal lesion score of mild to moderate intensity in chickens administered with EOT. Further, significantly higher (P < 0.05) daily body weight gains and antibody titers were detected in EOT administered chickens as compared to those of CT administered and control groups. EOT showed the immunostimulatory properties in broilers and their administration in chickens boost the protective immunity against coccidiosis.

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Potential of tannin-rich plants for modulating ruminal microbes and ruminal fermentation in sheep.

Abstract

The objective of this work was to study nutritional strategies for decreasing methane production by ruminants fed tropical diets, combining in vitro and in vivo methods. The in vitro approach was used to evaluate the dose effect of condensed tannins (CT) contained in leaves of Gliricidia sepium, Leucaena leucocephala, and Manihot esculenta (39, 75, and 92 g CT/kg DM, respectively) on methane production and ruminal fermentation characteristics. Tannin-rich plants (TRP) were incubated for 24 h alone or mixed with a natural grassland hay based on Dichanthium spp. (control plant), so that proportions of TRP were 0, 0.25, 0.5, 0.75, and 1.0. Methane production, VFA concentration, and fermented OM decreased with increased proportions of TRP. Numerical differences on methane production and VFA concentration among TRP sources may be due to differences in their CT content, with greater effects for L. leucocephala and M. esculenta than for G. sepium. Independently of TRP, the response to increasing doses of CT was linear for methane production but quadratic for VFA concentration. As a result, at moderate tannin dose, methane decreased more than VFA. The in vivo trial was conducted to investigate the effect of TRP on different ruminal microbial populations. To this end, 8 rumen-cannulated sheep from 2 breeds (Texel and Blackbelly) were used in two 4 × 4 Latin square designs. Diets were fed ad libitum and were composed of the same feeds used for the in vitro trial: control plant alone or combined with pellets made from TRP leaves at 44% of the diet DM. Compared to TRP, concentration of Ruminococcus flavefaciens was greater for the control diet and concentration of Ruminococcus albus was least for the control diet. The methanogen population was greater for Texel than for Blackbelly. By contrast, TRP-containing diets did not affect protozoa or Fibrobacter succinogenes numbers. Hence, TRP showed potential for mitigating methane production by ruminants. These findings suggest that TRP fed as pellets could be used to decrease methane production.

KEYWORDS:

methane; rumen microbial ecosystem; ruminal fermentation; sheep; tannin-rich plants; tropics

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Interaction of gut microflora with tannins in feeds.

Abstract

Tannins (hydrolyzable and condensed) are water-soluble polyphenolic compounds that exert antinutritional effects on ruminants by forming complexes with dietary proteins. They limit nitrogen supply to animals, besides inhibiting the growth and activity of ruminal microflora. However, some gastrointestinal microbes are able to break tannin-protein complexes while preferentially degrading hydrolyzable tannins (HTs). Streptococcus gallolyticus, Lonepinella koalarum and Selenomonas ruminantium are the dominant bacterial species that have the ability to degrade HTs. These tanninolytic microorganisms possess tannin-degrading ability and have developed certain mechanisms to tolerate tannins in feeds. Hence, selection of efficient tanninolytic microbes and transinoculation among animals for long-term benefits become areas of intensive interest. Here, we review the effects of tannins on ruminants, the existence and significance of tannin-degrading microorganisms in diverse groups of animals and the mechanisms that tannin-degrading microorganisms have developed to counter the toxic effects of tannin.

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assessment of the potential of cinnamaldehyde, condensed tannins, and saponins to modify milk fatty acid composition of dairy cows.

Abstract

This study was conducted to determine whether feeding cinnamaldehyde (main component of cinnamon bark essential oil; Cinnamon cassia), condensed tannins from quebracho trees (Schinopsis balansae), or saponins from Yucca schidigera altered the milk fatty acid profile of dairy cows. For this purpose, 4 lactating cows were used in 4 x 4 Latin square design (28-d period) and fed a total mixed ration containing no additive (control), or supplemented with cinnamaldehyde (1 g/d; CIN), quebracho condensed tannin extract (150 g/d; 70% of tannins; QCT), or Yucca schidigera saponin extract (60 g/d; 10% of saponins; YSE). Results revealed no effects of feeding CIN or QCT on milk fatty acid profile. Supplementation with YSE resulted in some modifications of milk fatty acid profile as suggested by the reduced proportions of C6:0 (2.71 vs. 2.95%), C8:0 (1.66 vs. 1.89%), and trans-11 C18:1 (0.92 vs. 1.01%). Results show low potential of cinnamaldehyde, condensed tannins, and saponins to alter ruminal biohydrogenation process and modify the fatty acid profile of milk fat at the feeding rates used in this study. Further investigations are needed to determine the factors that limit the effects of these secondary metabolites on ruminal microbial populations involved in the biohydrogenation processes of unsaturated fatty acids.

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Effect of condensed tannins supplementation through leaf meal mixture on voluntary feed intake, immune response and worm burden in Haemonchus contortus infected sheep.

Abstract

The study was carried out to assess the effect of condensed tannins (CT) supplementation through leaf meal mixture (LMM) on feed intake, humoral [Immunoglobulin G (IgG)], cell mediated immune response (CMI) and faecal egg counts in Haemonchus contortus infected sheep. Eighteen sheep were randomly divided into three groups (negative control-NC, infected control-C and Infected treatment-T) of six animals in each group in a completely randomized block design for a period of 90 days. Twelve H. contortus infected adult sheep were allocated into two equal groups C and T, supplemented with 0 and 1.5 % of CT, respectively. Six non-infected sheep of similar age and body weight of NC group were included in this study to compare their immune response with H. contortus C and CT supplemented T groups. Intake of dry matter and organic matter (g day(-1) and % live weight) was statistically similar (P < 0.05) among the three groups. The anti-Haemonchus IgG and CMI response was higher in T group as compared to C group. The mean faecal egg counts was significantly (P < 0.001) higher in C group as compared to T group. It may be concluded that dietary supplementation of CT (1.5 %) through LMM improved humoral and CMI immune response and decreased worm load in H. contortus infected sheep.

KEYWORDS:

Condensed tannins; Haemonchus contortus infection; Immune response; Leaf meal mixture; Sheep

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