Determination of Phytoestrogen Content in Fresh-Cut Legume Forage

Abstract

Simple SummaryPhytoestrogens comprise a group of substances negatively influencing the development and function of animal reproductive organs. Their appearance in forage crops can reduce feeding values, cause dietary disorders, and lead to animal health damage. This study evaluated the occurrence of individual phytoestrogens in various species of annual and perennial legumes and their levels in dry forage. It appeared that feeding large amounts of red clover presents a potential risk, but red clover can be replaced with the annual Persian clover, in which markedly lower phytoestrogen levels were detected.AbstractThe aim of the study was to determine phytoestrogen content in fresh-cut legume forage. This issue has been much discussed in recent years in connection with the health and safety of feedstuffs and thus livestock health. The experiments were carried out on two experimental plots at Troubsko and Vatín, Czech Republic during June and July in 2015. Samples were collected of the four forage legume species perennial red clover (variety “Amos”), alfalfa (variety “Holyně”), and annuals Persian clover and Alexandrian clover. Forage was sampled twice at regular three to four day intervals leading up to harvest and a third time on the day of harvest. Fresh and wilted material was analyzed using liquid chromatography–mass spectrometry (LC-MS). Higher levels (p < 0.05) of isoflavones biochanin A (3.697 mg·g−1 of dry weight) and formononetin (4.315 mg·g−1 of dry weight) were found in red clover than in other species. The highest isoflavone content was detected in red clover, reaching 1.001% of dry matter (p < 0.05), representing a risk for occurrence of reproduction problems and inhibited secretion of animal estrogen. The phytoestrogen content was particularly increased in wilted forage. Significant isoflavone reduction was observed over three to four day intervals leading up to harvest.

Polyphenols in Farm Animals: Source of Reproductive Gain or Waste?

“…For example, formononetin, daidzein, genistein, and biochanin A are the major polyphenols in Trifolium ( T .) subterraneum [ 17 ] and T. pratense [ 11 , 18 ] containing isoflavones, which account for up to 5% of dry matter [ 19 ], while coumestans are the major polyphenols in Medicago sativa [ 18 ] and Melilotus albus [ 20 ].…”

“…In traditional farming systems, Glycine max (soybean: [ 44 , 45 ]), Linum usitatissimum (linseed [ 44 ]), and clover species such as T. subterraneum [ 14 ], T. pratense L. (red clover [ 11 , 18 ]), and Trifolium alexandrinum (Berseem clover: [ 13 ]) are the most common sources of polyphenols in animal diets. Due to the limitation of traditional animal feed resources, many feed alternatives such as shrubs and trees are being introduced as new feedstuff.…”

Variation of Phytoestrogen Content and Major Agronomic Traits in Alfalfa (Medicago sativa L.) Populations

“…A strong association between formononetin intake and equol concentration in plasma was demonstrated, so that cows' milk can be considered as a source of equol in human nutrition [20][21][22][23][24][25]. On the other hand, consumption of forages with high concentrations of formononetin and coumestrol has shown to cause temporary or permanent reproductive problems in some ruminants, mostly in sheep and cattle [26][27][28][29][30].…”

Metabolic Profiling Provides Unique Insights to Accumulation and Biosynthesis of Key Secondary Metabolites in Annual Pasture Legumes of Mediterranean Origin

“…Significant levels of phytoestrogens are produced in pasture legumes including lucerne as well as various clover species and when present at significant levels can seriously reduce reproductive efficiency and livestock fertility [ 15 , 17 , 18 ]. Coumestans and isoflavone phytoestrogens are stable, non-steroidal secondary metabolites that mimic mammalian estrogen, an endogenous female sex hormone [ 15 , 19 ]. The affinity of these phytoestrogens in binding estrogen receptor- β can result in reproductive abnormalities during embryo development, and infertility in both sexes of grazing livestock [ 20 ].…”