Jens Hansen-Møller

Effects of Clover-Grass Silages and Concentrate Supplementation on the Content of Phytoestrogens in Dairy Cow Milk

A 2 x 2 factorial continuous experiment was conducted with 28 Norwegian Red dairy cows in early lactation to compare milk content of phytoestrogens when feeding ad libitum white clover (WCS) or red clover (RCS) grass silages prepared from the second and third cut without and with 10 kg/d supplementation of a standard concentrate. The cows were offered either RCS or WCS for 88 d (period 1) and thereafter a mixed red clover-white clover-grass silage for 48 d (period 2). Total dry matter intake and milk yield were not affected by forage type but increased with concentrate supplementation. Intake of isoflavones was several times greater in RCS than in WCS, whereas intake of lignans was greater in WCS. Concentrate supplementation reduced the intake of most phytoestrogens. Compared with WCS, RCS diets yielded milk with a greater content of flavonoids, whereas milk from WCS diets had greater contents of the mammalian lignans enterodiol and enterolactone. The content of the isoflavan equol was particularly high in RCS diets. There was no apparent carryover effect of clover type on milk phytoestrogen content because there was no difference in content between the silage treatments 3 wk after the cows were transferred to the same silage diet (period 2). Concentrate supplementation reduced the milk contents of the flavonoids equol, biochanin A, and daidzein and increased the content of mammalian lignans. The effects of silage type and concentrate supplementation on milk contents of the individual phytoestrogens were related to the intake of the compound or its precursor, except for the effect of concentrate on mammalian lignans, for which the intake of the known precursors was also reduced. Overall, this study shows that feeding cows with silage containing red clover increases the milk content of flavonoids at both low and high concentrate supplementation levels, and decreases the content of nonflavonoids such as mammalian lignans, when compared with silage containing white clover. The increased content of phytoestrogens in milk may be important when the health benefits of milk are studied.

Influence of chicory roots ( Cichorium intybus L ) on boar taint in entire male and female pigs

Boar taint is an off-flavour of pork caused primarily by a microbial breakdown product, skatole and a testicular steroid, androstenone. As skatole is produced in the large intestine from tryptophan, it is possible that some ‘bioactive’ ingredients could modify protein fermentation and, in the process, diminish boar taint. The aim of this study was to examine the effect of inulin-rich chicory roots (Cichorium intybus L.) on boar taint. In the first of three trials individually penned, entire males and females were given an organic concentrate in which 0·25 of the daily energy intake was replaced with crude chicory roots for 9 or 4 weeks prior to slaughter. In the second trial, entire male pigs were given diets that included, either crude chicory roots, dried chicory roots, or inulin (extracted from chicory roots) for 6 weeks pre-slaughter. In the third trial, intact male pigs were given the dried chicory diet for either 2 or 1 week before slaughter. In all trials the chicory diets were offered on a scale at 0·95 of the Danish recommendation for energy intake, and pig performance was compared with a control group given the organic concentrate at 0·95 of recommended energy intake plus silage ad libitum. In trial 1 an additional control group was offered the organic concentrate at a daily energy intake level of 1·0 of Danish recommendations. The pigs in trials 1, 2, and 3 were slaughtered at an average live weight of 118, 124, and 110kg, respectively, in order to ensure that they had achieved sexual maturity. Overall, skatole concentrations in blood plasma and backfat at slaughter were reduced to almost zero levels by including crude or dried chicory or inulin in the diet. This occurred irrespective of sex and length of feeding period (1 to 9 weeks). In trial 3 a significant effect on blood plasma concentration was observed after 3 days of feeding a diet containing dried chicory. The only significant reduction in plasma androstenone levels was detected in pigs given the crude chicory for a 9 week duration in trial 1. The production and proportion of lean was generally not affected by the addition of either form of chicory to the diets in trials 1 and 2. Therefore, dried chicory may be the most suitable form for commercial use because it: had no initial adverse effects on food intake, consistently reduced skatole without reducing performance, was easy to handle throughout the entire year and is relatively inexpensive.

High-performance ion chromatography method for separation and quantification of inositol phosphates in diets and digesta.

A gradient high-performance ion chromatographic method for separation and quantification of inositol phosphates (InsP(2)-InsP(6)) in feedstuffs, diets, gastric and ileal digesta from pigs was developed and validated. The InsP(2)-InsP(6) were separated on a Dionex CarboPac PA1 column using a gradient with 1.5 mol L(-1) methanesulfonic acid and water. The exchange of the commonly used HCl with methanesulfonic acid has two advantages: (i) the obtained baseline during the separation is almost horizontal and (ii) it is not necessary to use an inert HPIC equipment as the methanesulfonic acid is not as aggressive as HCl. Twenty-three of the 27 separated inositol phosphate isomers were isolated. ICP-MS was used for quantification of phosphorus in the isolated isomers and used for calculation of correction factors for each isomer allowing InsP(6) to be used as calibration standard. The detection limits for InsP(2)-InsP(6) were in the range of 0.9-4.4 mg phosphorus L(-1). The recovery of the major part of the inositol phosphates was 80-100%, and the CV for repeatability and reproducibility were 1-17% and 1-14%, respectively.

Effects of feeding dairy cows different legume-grass silages on milk phytoestrogen concentration

Phytoestrogens are hormone-like substances in plants that can substantially influence human health (positively or negatively), and when fed to dairy cows are partly transferred to their milk. The aim of this study was to investigate the effects of varying the botanical composition and regrowth interval of legume-grass silage on phytoestrogen intake and milk phytoestrogen concentrations. In one experiment, 15 Swedish Red dairy cows were fed 2- or 3-cut red clover-grass silage, or 2-cut birdsfoot trefoil-grass silage. In a second experiment, 16 Norwegian Red dairy cows were fed short-term ley silage with red clover or long-term ley silage with white clover, and the effects of supplementation with α-tocopherol were also tested. High concentrations of formononetin and biochanin A were found in all silage mixtures with red clover. The milk concentration of equol was highest for cows on the 2-cut red clover-grass silage diet (1,494 μg/kg of milk). Because of the metabolism of biochanin A, genistein, and prunetin, their concentrations in milk and the apparent recovery were low. Coumestrol was detected in only short-term and long-term ley silage mixtures, and its milk concentration was low. Concentrations of secoisolariciresinol and matairesinol were higher in 2-cut birdsfoot trefoil-grass and long-term ley silage mixtures, those with legume species other than red clover, and the highest grass proportions. The 2-cut birdsfoot trefoil-grass silage diet also resulted in higher enterolactone concentration than the other diets (226 μg/kg of milk). Lengthening the regrowth interval increased the intake of secoisolariciresinol and decreased the recovery of lignans. Feeding long-term ley silage resulted in higher milk lignan concentrations but lower milk isoflavone concentrations than feeding short-term ley silage. The apparent recovery of all phytoestrogens except prunetin was highest on the 2-cut birdsfoot trefoil-grass silage diet. No effect of α-tocopherol supplementation was observed on milk concentrations of any of the measured phytoestrogens. Variations were observed in milk concentrations of phytoestrogens, especially of equol, among cows, which could not be explained by variations in diet composition or phytoestrogen intake. The results show that milk phytoestrogen concentration is strongly influenced by silage botanical composition, but questions regarding phytoestrogen metabolism remain to be answered.

Effect of forage on the content of phyto-oestrogens in bovine milk

Phyto-oestrogens are believed to have a range of beneficial effects on predominant Western diseases. A few studies on phyto-oestrogens in milk exist and show that the composition can be affected by feeding. Therefore, the aim was to study how feeding of lucerne and grass/clover silages (GCSs) affects the concentration of phyto-oestrogens in bovine milk. Sixteen Danish Holstein cows were assigned to a 4 × 4 latin square design with four cows per treatment per period of 3 weeks. The four treatment diets were lucerne silage (LS), 2/3 lucerne silage and 1/3 maize silage (2/3LS), 1/3 lucerne silage and 2/3 maize silage (1/3LS) and GCS. Milk was collected at the end of each period and feed samples on day 6, 13 and 20 in each experimental period. Milk and pooled feed samples were analysed for the concentration of isoflavones, coumestans and lignans. The content of isoflavones was higher and the content of coumestrol lower in the GCS diet than in LS, 2/3LS and 1/3LS diets. For the LS, 2/3LS and 1/3LS diets, the concentration of coumestrol and secoisolariciresinol increased with the proportion of lucerne while the concentration of isoflavones was similar across the diets. The concentrations of the formononetin, daidzein and equol in the milk were significantly higher for the GCS diet than for the LS, 2/3LS and 1/3LS diets. In particular, the concentration of equol was 62-291 times higher for GCS. The concentration of coumestrol was significantly lower for the GCS diet compared to the LS, 2/3LS and 1/3LS diets. No pattern for the concentration of lignans was observed. In conclusion, a high concentration of isoflavones, particularly equol, and a low concentration of coumestrol were measured in the milk from the GCS diet. In contrast, a low concentration of isoflavones and a high concentration of coumestrol were measured in the milk from the LS, 2/3LS and 1/3LS diets. However, the concentration of phyto-oestrogens in bovine milk is low compared to food sources rich in phyto-oestrogens but the high concentration of equol could possibly be of therapeutic importance.

Gastrointestinal metabolism of phytoestrogens in lactating dairy cows fed silages with different botanical composition

Dietary phytoestrogens are metabolized or converted in the gastrointestinal tract of ruminants, only limited knowledge exists on the extent and location of this conversion in vivo. The objective of this study was to quantify the gastro-intestinal metabolism of phytoestrogens in lactating dairy cows fed silages with different botanical composition. Four lactating rumen cannulated Norwegian Red cattle were assigned to a 4 × 4 Latin square with 1 cow per treatment period of 3 wk. The 4 treatment silages were prepared from grasslands with different botanical compositions: organically managed short-term timothy (Phleum pratense L.) and red clover (Trifolium pratense L.) ley (2 yr old: ORG-SG); organically managed long-term grassland with a high proportion of unsown species (6 yr old; ORG-LG); conventionally managed perennial ryegrass (Lolium perenne L.) ley (CON-PR); and conventionally managed timothy ley (CON-TI). The herbages were cut, wilted, and preserved with additive in round bales, fed as a mix of the first and third cut at 90% of ad libitum intake, and contributed to 70% of the total dry matter intake. Milk, feed, omasal digesta, urine, and feces were collected at the end of each period and analyzed for the concentrations of phytoestrogens by using a liquid chromatography-tandem mass spectrometry technique. Concentration of total isoflavones was highest in ORG-SG and lowest in CON-TI silage, whereas the content of total lignans was highest in the grass silages. The isoflavones were extensively metabolized in the rumen on all diets, and the recovery of formononetin and daidzein in omasum, mainly as equol, averaged 0.11 mg/mg. The apparent intestinal metabolism was less severe as, on average, 0.29 mg/mg of the omasal flow was recovered in feces. The plant lignans were also strongly degraded in the rumen. However, the flow of lignans to omasum and excretion in feces were, on average, 7.2- and 5.2-fold higher, respectively, than the intake of the plant lignans matairesinol and secoisolariciresinol, known as precursors of mammalian lignans. Thus, excretion to milk could not be directly related to intake, implying that plant lignans other than matairesinol and secoisolariciresinol in forage are precursors for enterolactone production in the rumen and for its content in milk. Equol followed mainly the flow of large particles out of the rumen, whereas the mammalian lignans were distributed between phases proportional to dry matter flow. The main metabolism of phytoestrogens occurred in the rumen and the main route of excretion was through feces and urine, with only a small part being excreted in milk. The concentration of phytoestrogens in milk can be manipulated through intake but the intermediate transfer capacity to milk appears to be limited by saturation.

Influence of Keeping Pigs Heavily Fouled with Faeces plus Urine on Skatole and Indole Concentration (Boar Taint) in Subcutaneous Fat

Abstract The aim of this study was to investigate the effect on indole and skatole concentrations in subcutaneous fat (boar taint) of two housing conditions: keeping pigs heavily fouled with faeces on a concrete floor versus keeping pigs clean on a wholly slatted floor. Both groups of pigs were kept at a high stocking rate (0.6 m2 per pig) and high temperatures (≥25[ddot]C). This study also aimed to show if changing the treatment a week prior to slaughter is sufficient to change the concentration of indole and skatole in subcutaneous fat. The experimental material consisted of 158 LY (Danish Land-race x Large White) zigzag crossbred and LYD (Danish Land-race x Large White x Duroc) crossbred entire male, castrate, and female pigs. With the exception of the first delivery, where half of the pigs were kept constantly clean and the other half constantly dirty from the start of the experiment, both treatments were changed to the opposite treatment one week before delivery to the abattoir. Post-slaughter the co...

Changes in Concentrations of Cytokinins (CKs) in Root and Axillary Bud Tissue of Miniature Rose Suggest that Local CK Biosynthesis and Zeatin-Type CKs Play Important Roles in Axillary Bud Growth

Involvement of cytokinins (CKs) in axillary bud growth of miniature rose was studied. Variation in root formation and axillary bud growth was induced by two indole 3-butyric acid (IBA) pretreatments in two cutting sizes. At six physiological developmental stages around the onset of axillary bud growth, concentrations of CKs were determined in both root and axillary bud tissue by liquid chromatography combined with electrospray tandem mass spectrometry (LC-ESP-MS/MS). Chronological early onset of axillary bud growth occurred in long cuttings pretreated at low IBA concentration, whereas physiological early root formation was associated with long cuttings and high IBA concentration. The CKs zeatin (Z), isopentenyl adenine (iP), zeatin riboside (ZR), dihydrozeatin riboside (DHZR), isopentenyl adenosine (iPA), zeatin O-glucoside (ZOG), zeatin riboside O-glucoside (ZROG), zeatin riboside 5′-monophosphate (ZRMP), and isopentenyl adenosine 5′-monophosphate (iPAMP) were detected. Concentrations of CKs in axillary bud tissue far exceeded those in root tissue. Indole 3-butyric acid pretreatment influenced the concentration of CKs in axillary bud tissue more than did cutting size, whereas pretreatments only slightly affected CKs in root tissue. The dominant CKs found were iPAMP and ZR. An early and large increase in iPAMP indicated rapid CK biosynthesis in rootless cuttings, suggesting that green parts, including the axillary bud, can synthesize CKs. At the onset of axillary bud growth an increase in concentration of Z, ZR, ZRMP, ZOG, and ZROG was largely coincident with a decrease in iPAMP, iPA, iP, and DHZR. After the onset of axillary bud growth, CK content largely decreased. These results strongly indicate a positive role for CKs in axillary bud growth, and presumably ZRMP, ZR, and Z are active in miniature rose.

Phytoestrogens and their metabolites in bulk-tank milk: effects of farm management and season.

Phytoestrogens have structures similar to endogenous steroids and may induce or inhibit the response of hormone receptors. The objectives of the present study were to compare the effects of long-term vs. short-term grassland management in organic and conventional dairy production systems, compare organic and conventional production systems and assess seasonal variation on phytoestrogen concentrations in bulk-tank milk. The concentrations of phytoestrogens were analyzed in bulk-tank milk sampled three times in two subsequent years from 28 dairy farms: Fourteen organic (ORG) dairy farms with either short-term or long-term grassland management were paired with 14 conventional (CON) farms with respect to grassland management. Grassland management varied in terms of time since establishment. Short-term grassland management (SG) was defined as establishment or reseeding every fourth year or more often, and long-term grassland management (LG) was defined as less frequent establishment or reseeding. The proportion of red clover (Trifolium pretense L.) in the herbage was positively correlated with milk concentrations of the mammalian isoflavone equol. Therefore, organically produced bulk-tank milk contained more equol than conventionally produced milk, and milk from ORG-SG farms had more equol than milk from ORG-LG farms. Milk produced during the indoor-feeding periods had more equol than milk produced during the outdoor feeding period, because pastures contained less red clover than fields intended for silage production. Organically produced milk had also higher concentrations of the mammalian lignan enterolactone, but in contrast to equol, concentrations increased in the outdoor-feeding periods compared to the indoor-feeding periods. There were no indications of fertility problems on ORG-SG farms who had the highest red clover proportions in the herbage. This study shows that production system, grassland management, and season affect milk concentrations of phytoestrogens. However, compared to soy products, milk concentrations of phytoestrogens are low and future studies are required to investigate if the intake of phytoestrogens from dairy products has physiological effects in humans.

Assessment of the mobile bag method for estimation of in vivo starch digestibility.

The objective was to assess the ability of the in situ mobile nylon bag method for predicting small intestinal and total tract starch digestibility. Starch disappearance was measured for 18 samples of different cereals and legumes subjected to different physical and chemical processing methods and compared with coherent in vivo digestibility. Starch disappearance was measured both with and without initial ruminal pre-incubation during 4 h. Bags were retrieved from either the ileal cannula or faeces. Two dry Danish Holstein cows fitted with rumen cannulas were used for rumen pre-incubations and two lactating Danish Holstein cows fitted with duodenal and ileal cannulas were used for intestinal incubations. Rumen pre-incubation had no significant effect on disappearance from bags recovered in faeces. The disappearance of legume starch was lower, both in the rumen and small intestine, compared with starch from barley, wheat, oats, ear maize and maize. Transit times of the mobile bags from duodenum to ileum were not significantly different between feeds. A weak positive correlation was found between in vivo small intestinal and total tract digestibility of starch and disappearance obtained using the mobile bag technique across a broad range of starch sources. Omitting two less conventional starch sources (NaOH wheat and xylose-treated barley) resulted in a high (0.87) correlation between total tract in vivo digestibility and mobile bag disappearance. The use of the mobile bag method for estimation of in vivo starch digestibility will therefore depend on the starch type.