Adaptation by sheep to isoflavones in clover

1969 ◽  
Vol 9 (41) ◽  
pp. 569 ◽  
Author(s):  
FHW Morley ◽  
D Bennett ◽  
A Axelsen

Vaginal mucus scores and uterine weights of ovariectomized ewes that grazed subterranean clover for 13 days prior to tests were similar to those from ewes fed non-oestrogenic rations during this pre-treatment, if the leaves of test clovers contained high concentrations of formononetin (F) (Yarloop and Dinninup). No responses were obtained from subterranean clovers low in F, but high in genistein (G) or biochanin A (BA) (Clare and Bacchus Marsh) except for a group which was fed a non-oestrogenic diet during pre-treatment, and which gave a positive mucus test, but not a stgnificant uterine weight response. These results indicate that ewes can become non-responsive to G and BA, but not to F, and offer an explanation for some inconsistencies among bioassays of subterranean clovers. The task of selection and breeding of subterranean clover seems to be simplified since G and BA are unlikely to be harmful.


1989 ◽  
Vol 40 (4) ◽  
pp. 871 ◽  
Author(s):  
HL Davies

Uterotrophic responses in ovariectomized ewes when fed or grazed on Mount Barker, Yarloop or Dwalganup varieties of subterranean clover are reported. The high formononetin varieties Dwalganup and Yarloop always elicited a uterotrophic response. The low-formononetin, high-genistein and biochanin A variety, Mount Barker, stimulated a uterotrophic response, using a 5-day bioassay, when fed at 200g/day or 800g/day, but little or no response when grazed. When chopped lucerne hay was offered with 200 g of the Mount Barker the uterotrophic response was suppressed and the mean uterine weight was not significantly different from that of the negative controls (P= 0.57). The uterine weight of sheep eating 200 g/day of Yarloop and offered lucerne chaff or pellets in one experiment was lower (but not significantly lower) than the unsupplemented group. This trend may be worthy of further investigation.



1967 ◽  
Vol 18 (4) ◽  
pp. 647 ◽  
Author(s):  
DA Shutt ◽  
A Axelsen ◽  
HR Lindner

The plasma of sheep grazing various species of oestrogenic clover contained water-soluble conjugates of daidzein, formononetin, genistein, and biochanin A, chiefly in the form of glucuronides, in concentrations up to 40 µg/100 ml. In sheep pen-fed on red clover or subterranean clover (cv. Dinninup and Yarloop) the total concentration of these four isoflavones 3–5 hr after feeding ranged from 150 to 720 µg/100 ml plasma, of which 1–2% only was present in "free" (i.e. unconjugated) form; by 24 hr the plasma level had fallen to < 5 µg/100 ml plasma. Preconditioning the pen-fed sheep to oestrogenic clover, or adding lucerne to the diet, had no significant effect on the concentration of "free" or conjugated isoflavones in the plasma and had no inhibitory effect on the uterine weight response. Comparison of the composition of circulating isoflavones to that of the clover ingested indicated partial demethylation of formononetin to daidzein and of biochanin A to genistein, and suggested that genistein and biochanin A were degraded more rapidly than formononetin or daidzein in the sheep. Equol, a metabolite previously isolated from the urine of sheep treated with formononetin, was present in the plasma at a concentration of 50–170 µg/100 ml 24 hr after feeding.



1969 ◽  
Vol 20 (6) ◽  
pp. 1043 ◽  
Author(s):  
RC Rossiter

In experiments with young plants of the Dwalganup strain of subterranean clover, nitrogen deficiency was associated with increased concentrations of isoflavones in the expanded leaves and cotyledons. In the first trifoliate leaves the concentration of total isoflavones (formononetin+genistein+ biochanin A) was approximately doubled at low nitrogen supply. Biochanin A was much less affected than the other two isoflavones. The increase in isoflavone contents of nitrogen-deficient leaves was associated with decreased protein synthesis, but not always with increased sugar contents. The supply of carbon substrates for isoflavone synthesis may depend on starch as well as sugar contents. Practical implications of the results are considered briefly.



1995 ◽  
Vol 35 (3) ◽  
pp. 367 ◽  
Author(s):  
DGDe Marco ◽  
CB Li ◽  
PJ Randall ◽  
Marco DG De

This paper describes the tolerance to high concentrations of manganese (Mn) of pasture legumes that are suitable for the >500 mm rainfall zone in southern Australia. The legumes are lucerne (Medicago sativa), burr medic (M. polymorpha), murex medic (M. murex), balansa clover (Trifolium balansae), Persian clover (T. resupinatum), subterranean clover (T: subterraneum), greater lotus (Lotus pedunculatus), and seradella (Ornithopus compressus). Wheat (Triticum aestivum) cv. Egret and subterranean clover cvv. Mt Barker and Karridale were included to place the tolerance of the remaining species in the context of other studies.Symptoms of toxicity differed between species. Species ranking (in descending order) for Mn tolerance, and external threshold Mn concentrations (mmol/L), were subterranean clover (1.0), wheat (0.71), balansa clover (0.54), greater lotus (0.51), serradella (0.50), Persian clover (0.25), murex medic (0.24), burr medic (0.20), and lucerne (0.19). Critical toxicity concentrations derived from the relationships of yields to Mn concentrations in whole shoots for each species were as follows (mg Mn/kg DW): subterranean clover (2010), balansa clover (1330), serradella (1080), greater lotus (760), wheat (570), burr medic (440), murex medic (430), Persian clover (360), lucerne (190).



2002 ◽  
Vol 45 (12) ◽  
pp. 321-328 ◽  
Author(s):  
G. Andreottola ◽  
P. Foladori ◽  
M. Ragazzi ◽  
R. Villa

Dairy raw wastewater is characterised by high concentrations and fluctuations of organic matter and nutrient loads related to the discontinuity in the cheese production cycle and machinery washing. The applicability of a Moving Bed Biofilm Reactor (MBBR) filled with FLOCOR-RMP® plastic media to the treatment of dairy wastewater was evaluated in a pilot-plant. COD fractionation of influent wastewater, MBBR performance on COD and nutrient removal were investigated. A removal efficiency of total COD over 80% was obtained with an applied load up to 52.7 gCOD m−2 d−1 (corresponding to 5 kgCOD m−3d−1). The COD removal kinetics for the MBBR system was assessed. The order of the kinetics resulted very close to half-order in the case of a biofilm partially penetrated by the substrate. The nitrogen removal efficiency varied widely between 13.3 and 96.2% due to the bacterial synthesis requirement. The application of a MBBR system to dairy wastewater treatment may be appropriate when upgrading overloaded activated sludge plants or in order to minimise reactor volumes in a pre-treatment.



1992 ◽  
Vol 32 (8) ◽  
pp. 1061 ◽  
Author(s):  
AM Ridley ◽  
DR Coventry

Yield responses of 3 mixed grass-clover pastures [Phalaris aquatica L. cv. Sirosa (phalaris), Dactylis glomerata cv. Porto (cocksfoot), and annual grass based Trifolium subterraneum L. cv. Trikkala (subterranean clover) pastures] were measured over 5 soil pH treatments at 2 sites in Victoria. One site (Beechworth) was strongly acidic [pH(CaCl2) < 4.21 to a depth of 40 cm and contained high concentrations of soil aluminium (Al). At the other site (Lake Rowan), yield responses to lime application had been measured previously, but only in Al-sensitive wheat cultivars. At Beechworth, pasture yield responses to lime were not consistent but. when observed. occurred in autumn and winter in all 3 pasture types. Phalaris pastures showed yield increases more often than cocksfoot and annual pastures. Low magnesium and calcium concentrations may have limited dry matter production, although yields were reasonable on all treatments. Where lime was applied, growth responses may have been due to alleviation of Al toxicity. At Beechworth, pasture yield was increased where lime increased pH from 4.2 to 4.6 and decreased soil Al (measured in 10 mmol CaCl2/L) from 11 to <3 �g/g soil. Herbage manganese concentrations were not high in phalaris and subterranean clover, and cocksfoot manganese standards were not available. At Lake Rowan (pH 4.7, Al <1 �g/g), no growth responses to lime were seen in any pasture treatment, and annual grass based pastures sometimes had higher yields than phalaris and cocksfoot pastures. On strongly acidic soils such as at Beechworth, incorporation of lime prior to pasture establishment should be considered. Perennial grasses may reduce further soil degradation through acidification. Soil A1 concentrations are commonly lower in ley-cropping areas, and the inclusion of perennial grasses in ley pastures requires further evaluation.



2021 ◽  
Vol 26 (01) ◽  
pp. 60-68
Author(s):  
Hafiz Muhammad Rizwan

Trace elements play an important role to boost the immunity and fight against parasitic infections. Concentration of trace elements like Copper (Cu), Cobalt (Co), Manganese (Mn) and Zinc (Zn) were determined in soil, forages and sera of sheep. An associative analysis was also made between the burden of Gastrointestinal (GI) parasites and concentrations of trace elements of sheep sera. For this, 384 faecal and blood samples of sheep, an appropriate number of forages and soil samples were collected. The faecal samples were subjected to determine the species and burden of GI parasites. The sera, plant and soil samples were subjected to pre-treatment (digestion) required for the determination of trace elements. The overall prevalence of GI parasites was 32.81% and the most prevalent species were Haemonchus (H.) contortus followed in order by Eimeria spp., Strongyloides spp., Trichostrongylus spp. and Fasciola spp. Variables like age, sex, breed and tehsils of Silakot district showed an insignificant association with GI parasitic burden. Trace elements concentration of forages showed a significant (P < 0.05) variation while trace elements concentration of soil showed an insignificant (P > 0.05) variation. In serum, Zn concentration showed significant (P < 0.05) results among all the tehsils of study district. Mean concentrations of Mn and Cu in serum were found inversely proportional to the mean egg count per gram of sheep faeces in tehsil Pasroor of the Sialkot district. Forages containing high concentrations of Mn and Cu can be used effectively against GI parasites. © 2021 Friends Science Publishers



1988 ◽  
Vol 89 (4) ◽  
pp. 507-513
Author(s):  
J.G. Edwards ◽  
H. Hameed ◽  
G. Campbell

Mn2+ at low (microM) concentrations fulfils the divalent cation requirement for spreading of BHK21 cells on fibronectin. At much higher concentrations, Mn2+ (and to a small extent also Mg2+) induces spreading on haemoglobin, not normally an adhesive protein. Since high Mn2+ also induces spreading of BHK variants unresponsive to exogenous fibronectin, it is unlikely to be acting as a cofactor for secreted cellular fibronectin or by stimulating its secretion. High Ca2+, but not Mg2+, inhibits the induction of spreading by Mn2+ on haemoglobin. Pre-treatment of cells with high concentrations of trypsin decreases the rate of spreading induced by Mg2+ on fibronectin, and by Mn2+ on haemoglobin, to similar extents. High and low Mn2+ could induce spreading, either by different mechanisms or through a common pathway. In the second case, at both concentrations, Mn2+ could act by binding to Ca2+/Mg2+ sites in one or more receptors for adhesion proteins. This would require binding of Mn2+ or Mg2+ to these sites to activate the receptors in the absence of adhesion proteins, and the effect of such proteins to be to increase the affinity of the sites for metal ions. The sites in question may be formed by sequences homologous to those found in the extracellular domains of the vitronectin receptor and platelet membrane glycoprotein IIb. Although very similar to the Ca2+-binding loop in the EF hand of calmodulin, these sequences more closely resemble bacterial galactose-binding protein in lacking one of the conserved co-ordinating side-chains.



1985 ◽  
Vol 17 (1) ◽  
pp. 231-239 ◽  
Author(s):  
H Kroiss ◽  
F Plahl-Wabnegg ◽  
K Svardal

The waste water from the viscose production process can be characterized as follows: low to medium strength of biodegradable carbonaceous matter, high concentrations of sulfate, high concentrations of zinc. The treatment process to be presented consists of anaerobic pre-treatment of the neutralized waste water combining the removal of carbonaceous matter with zinc removal by sulfide precipitation. The organic pollution of the waste water is used as a substrate for sulfate reducing bacteria present in the anaerobic reactor. The hydrogen sulfide produced precipitates the zinc as insoluble zinc sulfide. Labscale experiments lasting several months resulted in stable zinc effluent concentrations below 1 mg/l combined with a COD removal of about 40 - 50 %.



2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Francesco Ricceri ◽  
Mattia Giagnorio ◽  
Giulio Farinelli ◽  
Giulia Blandini ◽  
Marco Minella ◽  
...  

Abstract The treatment of produced waters (by-products of oil and gas extraction) with the innovative process of membrane distillation is challenging, because these highly saline streams contain high concentrations of organic compounds and hydrocarbons that cause membrane wetting and impairment of performance. To design the most compact treatment scheme and with the aim of obtaining an easier management of produced water for reuse purposes, Fenton oxidation is here investigated as a feed pre-treatment that may produce an effluent easily handled by membrane distillation. In high-recovery membrane distillation tests, we systematically investigate the detrimental effects of individual contaminants in a synthetic produced water mimicking the composition of a real sample. The recovery rate depends strongly on the initial salinity, which eventually causes scaling and pore blocking. Surfactants are found to be mainly responsible for membrane wetting, but volatile and hydrophobic organics also spoil the quality of the product water. A Fenton oxidation pre-treatment is thus performed to degrade the target organics, with the aim of enhancing the effectiveness of the following membrane distillation and to improve the quality of the final product. The combined oxidation-membrane distillation scheme has both advantages and limitations, which need to be carefully evaluated and further investigated.



Sign in / Sign up

Export Citation Format

Share Document