The utilisation of a commercial polyethylene glycol preparation to ameliorate the influence of tannins on rumen environment

1996 ◽  
Vol 1996 ◽  
pp. 131-131
Author(s):  
M.B. Salawu ◽  
T. Acamovic ◽  
C.S. Stewart ◽  
F.D. DeB. Hovell

Quebracho (Loxopterygium loetzil) tannins (QT) are condensed tannins that reduce the digestibilities of nutrients in ruminants (Robbins, et al, 1991), probably by forming complexes with the dietary protein and carbohydrates and reducing microbial activities (Makkar, et al, 1988). Browse Plus (BP), a commercial preparation of polyethylene glycol (PEG) has recently been used to improve the nutritive value of tannin-containing browses. Trials on commercial farms in Zimbabwe have demonstrated that BP improved the nutritional performance of cattle fed high tannin diets (Anon., 1995). Some in vitro work tend to support these findings (Acamovic, et al, 1995). An experiment to study the effectiveness of BP in ameliorating the effects of QT on the rumen environment was conducted.

1996 ◽  
Vol 1996 ◽  
pp. 131-131
Author(s):  
M.B. Salawu ◽  
T. Acamovic ◽  
C.S. Stewart ◽  
F.D. DeB. Hovell

Quebracho (Loxopterygium loetzil) tannins (QT) are condensed tannins that reduce the digestibilities of nutrients in ruminants (Robbins, et al, 1991), probably by forming complexes with the dietary protein and carbohydrates and reducing microbial activities (Makkar, et al, 1988). Browse Plus (BP), a commercial preparation of polyethylene glycol (PEG) has recently been used to improve the nutritive value of tannin-containing browses. Trials on commercial farms in Zimbabwe have demonstrated that BP improved the nutritional performance of cattle fed high tannin diets (Anon., 1995). Some in vitro work tend to support these findings (Acamovic, et al, 1995). An experiment to study the effectiveness of BP in ameliorating the effects of QT on the rumen environment was conducted.


Author(s):  
A.C. Longland ◽  
M.K. Theodorou ◽  
S.J. Listerl ◽  
P. Morris ◽  
M. Gill

Condensed tannins have been implicated in reducing the nutritive value of potentially important feedstuffs, largely through reducing protein and fibre digestion. Tannins can mediate their effects directly by binding to the protein or fibre fraction rendering them resistant to digestion, or indirectly by binding with digestive enzymes, preventing their catalytic action. These adverse effects of tannins, however, can be mitigated by the use of agents such as polyethylene glycol (PEG) which form complexes with condensed tannins rendering them less effective as protein and fibre-binding agents. In this study, the effects of polyethylene glycol on (a) the in vitro fermentability and (b) the digestibility of the fibre fraction (= non-starch polysaccharide; NSP) of leaves of six tropical forage legumes varying in condensed tannin content was investigated.The species used, chosen for their varying tannin contents, were Sesbania goetzei (SG), S. seban (SS), Leucaena leucocephala (LL), Dioclea guianensis (DG) Calliandra sp. (C) and Tadehagi sp. (T23).


2014 ◽  
Vol 152 (6) ◽  
pp. 967-980 ◽  
Author(s):  
R. LIMA-OROZCO ◽  
I. VAN DAELE ◽  
U. ÁLVAREZ-HERNÁNDEZ ◽  
V. FIEVEZ

SUMMARYThe potential of ensiled sorghum–soybean as a ruminant feed has already been demonstrated; however, alternatives for soybean should be considered because other legumes such as jack bean (JB; Canavalia ensiformis (L.) DC.) and velvet bean (VB; Mucuna pruriens (L.) DC) might produce better yields under tropical conditions. First, the possibility for a qualitative conservation of these legumes in combination with sorghum was studied using lab-scale silages. Furthermore, the potential of additional molasses as a source of water-soluble carbohydrates (WSC) and a microbial inoculant (BIOPRANAL) to improve silage quality were assessed. As sorghum or legume tannins may influence the silage nutritive value, their importance was assessed through the addition of polyethylene glycol (PEG), which reduces tannin activity. Therefore, 25 treatments per legume–sorghum combination were created according to a central composite design. An acceptable silage quality was reached when at least half of the fresh biomass consisted of sorghum in combination with at least 15 g of additional WSC/kg fresh material. The nutritive value of mixed silages as well as pure sorghum silage in combination with dry jack beans was determined through in vitro digestibility in the rumen and small intestine. Polyethylene glycol increased the in vitro production of short-chain fatty acids, ammonia (NH3) concentrations and effective rumen dry matter and crude protein degradability for both mixed silages, indicating that tannins reduced rumen degradability. The latter action could be positive as the amount of digestible bypass protein increased when no PEG was added in the silo. Propionate and valerate proportions were increased through PEG addition to sorghum–JB and sorghum–VB silages, respectively, suggesting that the nature of the tannins differ between these legumes.


1997 ◽  
Vol 128 (3) ◽  
pp. 365-372 ◽  
Author(s):  
G. C. WAGHORN ◽  
I. D. SHELTON

The extent to which condensed tannins (CT) in Lotus corniculatus were able to affect protein degradation and the nutritive value of pasture were evaluated at Palmerston North, New Zealand in 1992 in an indoor feeding trial with sheep and using in vitro incubations. The feeding trial involved three groups of seven young wether sheep held indoors in metabolism crates for the 32-day experimental period with one group fed freshly cut ryegrass/clover pasture (Pasture group) whilst the other two groups received a mixture of c. 37% freshly cut Lotus corniculatus and 63% pasture (dry matter (DM) basis). One of the latter groups was given twice daily oral drenches of polyethylene glycol (PEG) to bind with and remove the effects of the CT (PEG group) whilst the remaining sheep (Tannin group) were not drenched. Intakes of sheep given the mixed diets were constrained to that of the pasture group. The CT concentration in the lotus was 26·1 g/kg DM so that the mixed diets contained c. 10g CT/kg DM. Effects of CT on digestion and sheep performance were minimal. Apparent digestibility of N was lower in the Tannin group (76·4%) than PEG (79·8%) or Pasture (79·4%) sheep (P<0·001), but there were no differences in DM digestibility (75%) or wool growth from mid-side patches. Rumen ammonia and soluble protein concentrations appeared to be similar in PEG and Tannin sheep and volatile fatty acid (VFA) concentrations were similar in all groups (100 mmol/l).For incubations in vitro, several ratios of Lotus corniculatus: pasture were used to determine the effects of CT on precipitation of soluble proteins and the net yield of ammonia and gas with and without PEG. Homogenates of Lotus corniculatus leaves and pasture showed that 50% of soluble protein was precipitated by 1·3% CT in homogenate DM and there was a substantial decrease in in vitro degradation to ammonia when lotus leaf accounted for 33% or more of DM with pasture. This work emphasises the need for caution when extrapolating from in vitro to the in vivo situation and suggests that 1% CT from Lotus corniculatus may be insufficient to affect the nutritive value of fresh forages for sheep.


1999 ◽  
Vol 79 (2) ◽  
pp. 203-212 ◽  
Author(s):  
L. R. McMahon ◽  
W. Majak ◽  
T. A. McAllister ◽  
J. W. Hall ◽  
G. A. Jones ◽  
...  

The effects of sainfoin (Onobrychis viciifolia) on digestion of alfalfa (Medicago sativa) were investigated in vitro and in vivo. Fresh alfalfa and sainfoin were incubated in an artificial rumen (Rusitec) in ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 (as-fed). Disappearances of dry matter and N from sainfoin were 77 and 65% of those from alfalfa, respectively. Protease and endoglucanase activities, NH3-N and methane production declined (P < 0.05) as sainfoin increased. Bacterial numbers and microbial outputs were unchanged (P > 0.05), but cells incorporated more 15NH3N as sainfoin in the diet increased. Chopped leaves (100:0, 95:5 and 90:10 alfalfa:sainfoin) were incubated for 48 h with diluted ruminal fluid containing 0 or 50 mg polyethylene glycol, which binds tannins. Gas and volatile fatty acid productions were similar (P > 0.05) across treatments, but including 10% sainfoin (without polyethylene glycol) reduced (P < 0.05) NH3 concentrations between 8 and 24 h. Sainfoin tannins reduced degradation of forage protein without affecting the digestibility of the nonprotein fraction. Alfalfa herbage was fed alone or with early- to full-bloom sainfoin herbage (at 10 or 20% of ad libitum alfalfa dry matter intake) or with sainfoin hay or pellets, to eight Jersey steers in crossover trials conducted over 4 yr. Including sainfoin in the diet reduced (P < 0.001) the incidence of bloat by 45 to 93% in 3 of 4 yr, irrespective of the form in which it was supplied. Co-feeding sainfoin can markedly reduce the incidence of bloat in ruminants consuming fresh alfalfa. Key words: Alfalfa, sainfoin, bloat, condensed tannins


1999 ◽  
Vol 133 (4) ◽  
pp. 445-454 ◽  
Author(s):  
E. M. SAARISALO ◽  
A. A. ODENYO ◽  
P. O. OSUJI

Methods to alleviate the toxicity of Acacia angustissima (acc. no 15132) were evaluated in vitro and in vivo at ILRI Debre Zeit Research station in Ethiopia in 1997–1998. In an in vitro evaluation, A. angustissima leaves were incubated for 120 h with rumen fluid from Borana steers consuming native hay and cotton seed cake or from free ranging goat and sheep. Addition of polyethylene glycol (PEG, molecular weight (MW) 4000) increased gas production (4·9 v. 13·9 ml/100 mg dry matter (DM)), ammonia concentration (5·2 v. 9·7 mmol/l) and neutral detergent fibre (NDF) digestibility (380 v. 540 g/kg DM). In an in vivo experiment, Ethiopian highland sheep fed native hay and A. angustissima as a supplement (200 g/d) were inoculated with mixed rumen content from sheep gradually adapted on A. angustissima or were given PEG (MW 4000, 100 g/kg supplement) as methods to alleviate toxicity induced by A. angustissima. Sesbania sesban (acc. no 10865) with and without PEG were fed as a control. Effects on intake, apparent digestibility and nitrogen balance were studied in a 5×5 Latin square experiment. DM intake was increased by all the supplements (P<0·001) even though hay intake was slightly reduced compared to hay only (P<0·05). PEG increased intake of A. angustissima compared to inoculation. There were no significant differences in apparent DM or OM digestibility. Apparent nitrogen digestibility tended to be higher with S. sesban than with A. angustissima (P<0·10) and addition of PEG increased it with A. angustissima (P<0·05). Supplements increased ammonia and VFA concentrations and molar proportion of propionate (P<0·05). Supplements tended to increase microbial nitrogen supply (P<0·10) but there were no significant differences in efficiency of microbial synthesis. Supplements increased nitrogen retention (P<0·01) but due to short periods there were no significant differences in the live weights of sheep. All the animals remained healthy during the experiment suggesting that both methods used alleviated the toxicity of A. angustissima. Addition of PEG was more effective than inoculation in increasing intake and nutritive value of A. angustissima.


1998 ◽  
Vol 6 (1) ◽  
pp. 175-181 ◽  
Author(s):  
A.V. Goodchild ◽  
F.J. El Haramein ◽  
A. Abd El Moneim ◽  
H.P.S. Makkar ◽  
P.C. Williams

Near infrared (NIR) spectroscopy calibrations for measures of tannins and nutritive value were made on a set of 40 hays and straws of Vicia and Lathyrus spp. by the modified partial least squares (MPLS) method and were evaluated by cross-validation. They successfully predicted, in the dry matter, 4.6–34.1 g kg−1 total phenolics with a cross-validation R2 of 0.95 and a SECV of 1.68 g kg−1, 1.3–23.1 g kg−1 total tannins ( R2 = 0.89, SECV = 1.84 g kg−1) and 0.5–30.3 g kg−1 condensed tannins ( R2 = 0.93, SECV = 2.34 g kg−1). In multiple regression and MPLS calibrations, a wavelength close to 2.144 μm was common to all measures of tannins, and was attributed to condensed tannins and its flavanoid precursors. The biological activity of tannins on rumen microbes, measured as a 0–6.9% effect on gas production with rumen liquor in vitro, was less precisely predicted by MPLS ( R2 = 0.49, SECV = 1.49%). The biological activity per gram of chemical tannins could not be predicted by NIR spectroscopy in the material studied. Acid detergent fibre, neutral detergent fibre, crude protein and gas production in vitro were predicted with R2 = 0.95 to 0.96 ( SECV = 18.2, 24.8, 10.1 g kg−1 or 7.2 mL g−1).


Author(s):  
Khaoula Khelalfa ◽  
Rabah Arhab ◽  
Antonio Ignacio Martín-García ◽  
Nabila Zaabat ◽  
Alejandro Belanche

Condensed tannins are polyphenolic compounds which can exert beneficial effects in ruminants. They have the ability to bind proteins and decrease their degradation. They have also been reported to reduce methanogenesis and improve ruminants performances. The present work aimed to study the effect of purified condensed tannins from Acacia horrida extract on fermentation parameters, gas and methane production. In this context, seven substrates were selected: four Acacia species (Acacia pycnantha, Acacia dealbata, Acacia horrida and Acacia cyanophylla) and three plant by-products (date palm leaves, grenade peel and artichoke stems). Biological activity of tannins was evaluated by the incubation of the substrates in vitro with Polyethylene glycol (PEG). Tannins decreased concentration of all fermentation parameters (gas (p < 0.0001), methane (CH4) (p= 0.0983), ammonia (N-NH3) (p= 0.0382), Volatile Fatty Acids (VFA) (p= 0.0009), acetate (p <0.0001), propionate (p= 0.1024), butyrate (p= 0.0373), isobutyrate (p= 0.0046), valerate (p < 0.0001), isovalerate (p= 0.0032)). Substrates were also characterized by their content in main nutrients (dry matter (DM), organic matter (OM), ash, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) ,acid detergent lignin (ADL)) and in secondary metabolites (total phenols (TP), total tannins (TT) and condensed tannins (CT) ). All substrates presented high CP content except by-products (> 100 g/kg DM) and moderate cell-wall components. CT content was comprised between 120.5 and 680.4 g/kg DM in plants and between 23.1 and 170.4 g/kg DM in plant by-products. A. horrida presented the highest biological activity. Thus, their CT were extracted and purified on a sephadex LH-20 column. Purified tannins from A. horrida were incubated with two different forages alfalfa hay and barley straw at three different concentrations: 50, 100, 150 mg/g DM. Results showed that purified tannins from A. horrida had no effect on fermentation parameters (P > 0.05). The effects of A. horrida tannins may be strongly linked to their structure and their molecular weight more than to their concentration. For this reason, it is interesting that this work may be completed by physical characterization of these tannins.


2007 ◽  
Vol 47 (2) ◽  
pp. 170 ◽  
Author(s):  
K. Robinson ◽  
L. W. Bell ◽  
R. G. Bennett ◽  
D. A. Henry ◽  
M. Tibbett ◽  
...  

Six Australian native herbaceous perennial legumes (Lotus australis, Swainsona colutoides, Swainsona swainsonioides, Cullen tenax, Glycine tabacina and Kennedia prorepens) were assessed in the glasshouse for nutritive value, soluble condensed tannins and production of herbage in response to three cutting treatments (regrowth harvested every 4 and 6 weeks and plants left uncut for 12 weeks). The Mediterranean perennial legumes Medicago sativa and Lotus corniculatus were also included. Dry matter (DM) yield of some native legumes was comparable to L. corniculatus, but M. sativa produced more DM than all species except S. swainsonioides after 12 weeks of regrowth. Dry matter yield of all native legumes decreased with increased cutting frequency, indicating a susceptibility to frequent defoliation. Shoot in vitro dry matter digestibility (DMD) was high (>70%) in most native legumes, except G. tabacina (65%) and K. prorepens (55%). Crude protein ranged from 21–28% for all legumes except K. prorepens (12%). More frequent cutting resulted in higher DMD and crude protein in all species, except for the DMD of C. tenax and L. australis, which did not change. Concentrations of soluble condensed tannins were 2–9 g/kg DM in the Lotus spp., 10–18 g/kg DM in K. prorepens and negligible (<1 g/kg) in the other legumes. Of the native species, C. tenax, S. swainsonioides and L. australis showed the most promise for use as forage plants and further evaluation under field conditions is now warranted.


Sign in / Sign up

Export Citation Format

Share Document