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the multi-year cumulative effects of alternative stocking rate and grazing management practices on pasture productivity and utilization efficiency.the production and utilization of increased quantities of high quality pasture is of paramount importance in pasture-based milk production systems. the objective of this study was to evaluate the cumulative effects of alternative integrated grazing strategies, incorporating alternative stocking rate (sr) and grazing severities, on pasture productivity and grazing efficiency over multiple years within farm systems using perennial ryegrass dominant pastures. three whole-farm sr treatments were com ...201626898285
herbage intake and ruminal digestion of dairy cows grazed on perennial ryegrass pasture either in the morning or evening.this study aimed to clarify diurnal fluctuations of herbage intake, ruminal fermentation of herbage carbohydrates and proteins, and digesta particulate weight in the rumen of grazing dairy cows. six ruminally cannulated, non-lactating dairy cows were grazed on perennial ryegrass/white clover pasture either in the morning (04.00 to 08.00 hours) or the evening (16.00 to 20.00 hours). cows grazed in the evening spent more time (p < 0.01) and consumed more herbage (p < 0.01) compared with cows graze ...201626607997
milk production responses to different strategies for feeding supplements to grazing dairy cows.milk production responses of grazing cows offered supplements in different ways were measured. holstein-friesian cows, averaging 45 d in milk, were allocated into 8 groups of 24, with 2 groups randomly assigned to each of 4 feeding strategies. these were control: cows grazed a restricted allowance of perennial ryegrass pasture supplemented with milled wheat grain fed in the milking parlor and alfalfa hay offered in the paddock; fgm: same pasture and allowance as the control supplemented with a f ...201626585473
temporal dynamics of the metabolically active rumen bacteria colonizing fresh perennial ryegrass.this study investigated successional colonization of fresh perennial ryegrass (prg) by the rumen microbiota over time. fresh prg was incubated in sacco in the rumens of three holstein × friesian cows over a period of 8 h, with samples recovered at various times. the diversity of attached bacteria was assessed using 454 pyrosequencing of 16s rrna (cdna). results showed that plant epiphytic communities either decreased to low relative abundances or disappeared following rumen incubation, and that ...201626542074
herbage intake and milk production of late-lactation dairy cows offered a second-year chicory crop during summer.chicory (cichorum intybus l.) is a summer-active forage herb which has been proposed as an option to increase summer feed supply, increase dry matter intake, nutrient intake, and milk yield from nonirrigated dairy production systems in southern australia. dry matter intake, nutrient intake, milk yield, and yield of milk fat and protein of predominantly holstein-friesian dairy cows in late lactation consuming 3 herbage-based diets (4 replicates per treatment) were measured. the 3 grazed herbages ...201526409973
replacement of grass and maize silages with lucerne silage: effects on performance, milk fatty acid profile and digestibility in holstein-friesian dairy cows.in total, 20 multiparous holstein-friesian dairy cows received one of four diets in each of four periods of 28-day duration in a latin square design to test the hypothesis that the inclusion of lucerne in the ration of high-yielding dairy cows would improve animal performance and milk fatty acid (fa) composition. all dietary treatments contained 0.55 : 0.45 forage to concentrates (dry matter (dm) basis), and within the forage component the proportion of lucerne (medicago sativa), grass (lolium p ...201526242305
application of long-chain alcohols as faecal markers to estimate diet composition of horses and cattle fed with herbaceous and woody species.utilization of long-chain alcohols (lcoh) as diet composition markers in horses and cattle was assessed in a study conducted with 12 mature crossbreed mares (385±47 kg bw) and six adult non-lactating cows (499±36 kg bw) of asturiana de los valles breed. the lcoh data were combined with alkane and long-chain fatty acid (lcfa) data to test the applicability of combining these markers to estimate diet composition. animals were randomly divided into groups of three animals and received a daily total ...201526160068
short communication: grazing pattern of dairy cows that were selected for divergent residual feed intake as calves.the aim of this study was to investigate and assess differences in the grazing pattern of 2 groups of mature dairy cows selected as calves for divergent residual feed intake (rfi). sixteen holstein-friesian cows (471±31kg of body weight, 100 d in milk), comprising 8 cows selected as calves (6-8 mo old) for low (most efficient: csclowrfi) and 8 cows selected as calves for high (least efficient: cschighrfi) rfi, were used for the purpose of this study. cows (n=16) were managed as a single group, a ...201526162793
response of plasma glucose, insulin, and nonesterified fatty acids to intravenous glucose tolerance tests in dairy cows during a 670-day lactation.this experiment investigated the metabolic response of dairy cows undergoing an extended lactation to a frequently sampled intravenous glucose tolerance test. the experiment used 12 multiparous holstein cows that calved in late winter in a seasonally calving pasture-based system and were managed for a 670-d lactation by delaying rebreeding. in each of four 5-wk experimental periods commencing at approximately 73, 217, 422, and 520 (±9.1) days in milk (dim), cows were offered a diet of perennial ...201525468690
ergot alkaloid intoxication in perennial ryegrass (lolium perenne): an emerging animal health concern in ireland?four primary mycotoxicosis have been reported in livestock caused by fungal infections of grasses or cereals by members of the clavicipitaceae family. ergotism (generally associated with grasses, rye, triticale and other grains) and fescue toxicosis (associated with tall fescue grass, festuca arundinacea) are both caused by ergot alkaloids, and referred to as 'ergot alkaloid intoxication'. ryegrass staggers (associated with perennial ryegrass lolium perenne) is due to intoxication with an indole ...201425295161
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 si ...201425306275
traditional vs modern: role of breed type in determining enteric methane emissions from cattle grazing as part of contrasting grassland-based systems.ruminant livestock turn forages and poor-quality feeds into human edible products, but enteric methane (ch4) emissions from ruminants are a significant contributor to greenhouse gases (ghgs) and hence to climate change. despite the predominance of pasture-based beef production systems in many parts of europe there are little data available regarding enteric ch4 emissions from free-ranging grazing cattle. it is possible that differences in physiology or behaviour could influence comparative emiss ...201425259617
evaluation of physical structure value in spring-harvested grass/clover silage and hay fed to heifers.the physical structure value of conserved grass/clover forages of spring harvest was evaluated by assessing effects of harvest time, conservation method, indf/ndf ratio and ndf intake (ndfi) per kg bw on chewing activity and fecal particle size in dairy heifers. a mixed sward consisting of ryegrass (lolium perenne), red clover (trifolium pratense) and white clover (trifolium repens) was harvested in 2009 on may 9 (early) and 25 (late), and both cuts were conserved as silage and hay. the early si ...201525245025
effect of concentrate feed level on methane emissions from grazing dairy cows.although the effect of nutrition on enteric methane (ch4) emissions from confined dairy cattle has been extensively examined, less information is available on factors influencing ch4 emissions from grazing dairy cattle. in the present experiment, 40 holstein-friesian dairy cows (12 primiparous and 28 multiparous) were used to examine the effect of concentrate feed level (2.0, 4.0, 6.0, and 8.0 kg/cow per day; fresh basis) on enteric ch4 emissions from cows grazing perennial ryegrass-based swards ...201425173463
the role of the oregon state university endophyte service laboratory in diagnosing clinical cases of endophyte toxicoses.the oregon state university colleges of veterinary medicine and agricultural sciences instituted the endophyte service laboratory to aid in diagnosing toxicity problems associated with cool-season grasses in livestock. the endophyte (neotyphodium coenophalum) present in tall fescue (festuca arundinacea) produces ergopeptine alkaloids, of which ergovaline is the molecule used to determine exposure and toxicity thresholds for the vasoconstrictive conditions "fescue foot" and "summer slump". anothe ...201425017309
effects of partial mixed rations and supplement amounts on milk production and composition, ruminal fermentation, bacterial communities, and ruminal acidosis.late-lactation holstein cows (n=144) that were offered 15kg dry matter (dm)/cow per day of perennial ryegrass to graze were randomized into 24 groups of 6. each group contained a fistulated cow and groups were allocated to 1 of 3 feeding strategies: (1) control (10 groups): cows were fed crushed wheat grain twice daily in the milking parlor and ryegrass silage at pasture; (2) partial mixed ration (pmr; 10 groups): pmr that was isoenergetic to the control diet and fed twice daily on a feed pad; ( ...201424997657
influence of different systems for feeding supplements to grazing dairy cows on milk fatty acid composition.this study investigated the effects of different strategies for feeding supplements to grazing dairy cows on the proportions of fatty acids in milk. two hundred and sixteen cows were fed supplementary grain and forage according to one of 3 different strategies; (1) control: cows grazed perennial ryegrass pasture (14 kg dry matter/d) supplemented with milled barley grain fed in the milking parlour and pasture silage offered in the paddock; (2) partial mixed ration 1 (pmr1): same pasture allotment ...201424560061
effects of chicory/perennial ryegrass swards compared with perennial ryegrass swards on the performance and carcass quality of grazing beef steers.an experiment investigated whether the inclusion of chicory (cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (lolium perenne). triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. forty-eight belgian blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. the ex ...201424489708
forage fiber effects on particle size reduction, ruminal stratification, and selective retention in heifers fed highly digestible grass/clover silages.the objective of this study was to investigate the effect of ndf content in highly digestible grass/clover silage on particle size reduction, ruminal stratification, and selective retention in dairy heifers. the reduction in particle size from feed to feces was evaluated and related to feed intake, chewing activity, and apparent digestibility. four grass/clover harvests (mixtures of lolium perenne, trifolium pratense, and trifolium repens) were performed from early may to late august at differen ...201424671592
milk production and enteric methane emissions by dairy cows grazing fertilized perennial ryegrass pasture with or without inclusion of white clover.an experiment was undertaken to investigate the effect of white clover inclusion in grass swards (gwc) compared with grass-only (go) swards receiving high nitrogen fertilization and subjected to frequent and tight grazing on herbage and dairy cow productivity and enteric methane (ch4) emissions. thirty cows were allocated to graze either a go or gwc sward (n=15) from april 17 to october 31, 2011. fresh herbage [16 kg of dry matter (dm)/cow] and 1 kg of concentrate/cow were offered daily. herbage ...201424393178
milk production and composition of mid-lactation cows consuming perennial ryegrass-and chicory-based diets.dry matter intakes (dmi), nutrient selection, and milk production responses of dairy cows grazing 3 herbage-based diets offered at 2 allowances were measured. the 2 allowances were 20 (low) and 30 (high) kg of dry matter (dm)/cow per day and these were applied to 3 herbage types: perennial ryegrass (prg) and chicory (chic+) monocultures and a mixed sward of chicory and perennial ryegrass (mix). the chic+ diet was supplemented with alfalfa hay (approximately 2 kg of dm/cow per day) to maintain di ...201424290818
effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (lolium perenne l.) pastures.a grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (hm) on dairy cow performance, grass dry matter (dm) production and output from perennial ryegrass (lolium perenne l.) pastures. cows were randomly assigned to one of three pre-grazing hm treatments: 1150 - low hm (l), 1400 - medium hm (m) or 2000 kg dm/ha - high hm (h). herbage accumulation under grazing was lowest (p<0.01) on the l treatment and cows grazing the l pastures required more ...201424229787
passage of stable isotope-labeled grass silage fiber and fiber-bound protein through the gastrointestinal tract of dairy cows.fractional passage rates are required to predict nutrient absorption in ruminants but data on nutrient-specific passage kinetics are largely lacking. with the use of the stable isotope ratio (δ) as an internal marker, we assessed passage kinetics of fiber and fiber-bound nitrogen (n) of intrinsically labeled grass silage from fecal and omasal excretion patterns of δ(13)c and δ(15)n. in a 6×6 latin square, lactating dairy cows received grass silages [455 g/kg of total diet dry matter (dm) ] in a ...201324119806
dairy cows increase ingestive mastication and reduce ruminative chewing when grazing chicory and plantain.although the nutritive value of chicory (cichorium intybus l.) and plantain (plantago lanceolata l.) has been thoroughly studied, little is known about the grazing behavior of cattle feeding on chicory and plantain swards. the objective of the present study was to assess and describe the grazing behavior of dairy cows as affected by dietary proportions of chicory and plantain fed as monocultures for part of the day. ninety holstein-friesian cows (489±42 kg of body weight; 4.1±0.3 body condition ...201324119808
risks associated with the transfer of toxic organo-metallic mercury from soils into the terrestrial feed chain.although the transfer of organo-metallic mercury (orghg) in aquatic food webs has long been studied, it has only been recently recognized that there is also accumulation in terrestrial systems. there is still however little information about the exposure of grazing animals to orghg from soils and feed as well as on risks of exposure to animal and humans. in this study we collected 78 soil samples and 40 plant samples (lolium perenne and brassica juncea) from agricultural fields near a contaminat ...201323917441
fatty acid oxidation products ('green odour') released from perennial ryegrass following biotic and abiotic stress, potentially have antimicrobial properties against the rumen microbiota resulting in decreased biohydrogenation.in this experiment, we investigated the effect of 'green odour' products typical of those released from fresh forage postabiotic and biotic stresses on the rumen microbiota and lipid metabolism.201323889811
differences in rate of ruminal hydrogenation of c18 fatty acids in clover and ryegrass.biohydrogenation of c18 fatty acids in the rumen of cows, from polyunsaturated and monounsaturated to saturated fatty acids, is lower on clover than on grass-based diets, which might result in increased levels of polyunsaturated fatty acids in the milk from clover-based diets affecting its nutritional properties. the effect of forage type on ruminal hydrogenation was investigated by in vitro incubation of feed samples in rumen fluid. silages of red clover, white clover and perennial ryegrass har ...201323842207
toxicological evaluation and bioaccumulation potential of lolitrem b, endophyte mycotoxin in japanese black steers.lolitrem b, a causative toxin for ryegrass staggers, is produced by neotyphodium lolii infecting perennial ryegrass (lolium perenne). japanese black cattle have been suspected to be more sensitive to lolitrem b than to other strains, and there has been a concern about the public health hazard of eating beef contaminated with lolitrem b. we carried out a feeding experiment to examine the sensitivity of japanese black cattle to lolitrem b and the residual level of lolitrem b in several animal tiss ...201323721156
nitrous oxide emissions from in situ deposition of n-labeled ryegrass litter in a pasture soil.during pasture grazing, freshly harvested herbage (litterfall) is dropped onto soils from the mouths of dairy cattle, potentially inducing nitrous oxide (no) emissions. although the intergovernmental panel on climate change (ipcc) recommends accounting for no emissions from arable crop residues in national inventories, emissions from the litterfall of grazed pasture systems are not recognized. the objective of this study was to investigate the potential of litterfall to contribute to no emission ...201323673824
the effect of target postgrazing height on sward clover content, herbage yield, and dairy production from grass-white clover pasture.white clover (trifolium repens) is an important legume for grazed grassland that can increase the profitability and environmental sustainability of milk production. previous experiments on mown grass-clover plots suggest that low postgrazing heights (pgh) can increase sward clover content and herbage production. however, this has not been tested in actual strip or rotational grazing systems with dairy cows. furthermore, lowering pgh in grass-only swards (typically perennial ryegrass without whit ...201323332838
successional colonization of perennial ryegrass by rumen bacteria.this study investigated successional colonization of perennial ryegrass (prg) by the rumen microbiota. prg grown for 6 weeks in a greenhouse was incubated in sacco in the rumens of three holstein × freisian cows over a period of 24 h. prg incubated within the rumen was subsequently harvested at various time intervals postincubation to assess colonization over time. dgge-based dendograms revealed the presence of distinct primary (0-2 h) and secondary (4 h onwards) attached bacterial communities. ...201323206248
effect of silage botanical composition on ruminal biohydrogenation and transfer of fatty acids to milk in dairy cows.ruminal biohydrogenation and transfer of fatty acids (fa) to milk were determined for 4 silages with different botanical compositions using 4 multiparous norwegian red dairy cows [(mean ± sd) 118 ± 40.9 d in milk, 22.5 ± 2.72 kg of milk/d, 631 ± 3.3 kg of body weight, 3.3 ± 0.40 points on body condition score at the start of the experiment] fitted with rumen cannulas. treatments consisted of 4 experimental silages: a mix of the first and third cut of organically managed short-term grassland with ...201323200474
δ 13c as a marker to study digesta passage kinetics in ruminants: a combined in vivo and in vitro study.the aim of the current study was to explore the use of the tracer 13c as an internal marker to assess feed fraction-specific digesta passage kinetics through the digestive tract of dairy cows. knowledge on feed-specific fractional passage rates is essential to improve estimations on the extent of rumen degradation and microbial protein efficiency; however, this information is largely lacking. an in vivo and in vitro experiment was conducted with grass silages (lolium perenne l.) that were enrich ...201323211548
effects of different strategies for feeding supplements on milk production responses in cows grazing a restricted pasture allowance.milk production responses of grazing cows offered supplements in different ways were measured. holstein-friesian cows, averaging 227 d in milk, were allocated into 6 groups of 36, with 2 groups randomly assigned to each of 3 feeding strategies: (1) cows grazed perennial ryegrass pasture supplemented with milled barley grain fed in the milking parlor and pasture silage offered in the paddock (control); (2) same pasture and allotment supplemented with the same amounts of milled barley grain and pa ...201323219117
soil intake of lactating dairy cows in intensive strip grazing systems.involuntary soil intake by cows on pasture can be a potential route of entry for pollutants into the food chain. therefore, it appears necessary to know and quantify factors affecting soil intake in order to ensure the food safety in outside rearing systems. thus, soil intake was determined in two latin square trials with 24 and 12 lactating dairy cows. in trial 1, the effect of pasture allowance (20 v. 35 kg dry matter (dm) above ground level/cow daily) was studied for two sward types (pure per ...201223217239
effect of perennial ryegrass (lolium perenne l.) cultivars on the milk yield of grazing dairy cows.the objective of this experiment was to investigate the effect of four perennial ryegrass cultivars: bealey, astonenergy, spelga and abermagic on the milk yield and milk composition of grazing dairy cows. two 4 × 4 latin square experiments were completed, one during the reproductive and the other during the vegetative growth phase of the cultivars. thirty-two holstein-friesian dairy cows were divided into four groups, with each group assigned 17 days on each cultivar during both experiments. wit ...201323034142
the evaluation of fungal endophyte toxin residues in milk.to determine the concentrations of fungal endophyte toxins in the milk of cows fed perennial ryegrass containing wild-type or ar37 endophyte.201322984816
nitrogen metabolism and rumen microbial enumeration in lactating cows with divergent residual feed intake fed high-digestibility pasture.dairy cattle selected for negative residual feed intake (n-rfi; efficient) should maintain production while reducing dry matter intake over a lactation because of improvements in feed digestion and efficient use of nutrients. the objective of this study was to measure nitrogen (n) digestibility and rumen microbial community composition over a short period during early lactation in lactating holstein-friesian cows selected previously for divergent rfi. it was proposed that n-rfi cows would have g ...201222916906
effects of novel and wild-type endophytes in perennial ryegrass on cow health and production.to measure the effects of ar37, ar1 and wild-type endophytes in perennial ryegrass on cow health and milk production.201322913546
effect of supplementary concentrate type on nitrogen partitioning in early lactation dairy cows offered perennial ryegrass-based pasture.forty-four early lactation (64 ± 20 d in milk) dairy cows of mixed parity were used to assess the effect of 4 supplementary concentrate types (n=11) on n partitioning. animals were blocked on parity and calving date, and blocks were balanced for previous milk yield and milk protein yield. cows received grazed pasture plus 5.17 kg of dry matter (dm)/d of one of the following isoenergetic concentrates: high crude protein (cp) with rolled barley (hp, 19% cp); low cp with rolled barley (lp, 15% cp); ...201222818461
effect of supplemental concentrate type on milk production and metabolic status in early-lactation dairy cows grazing perennial ryegrass-based pasture.forty-four early-lactation dairy cows of mixed parity were used to examine the effect of 4 supplemental concentrate types (n=11) on milk production and metabolic status. animals were blocked by parity and calving date, and blocks were balanced for previous milk yield and milk protein yield. cows received grazed pasture plus 5.17 kg of dm/d of 1 of the following isoenergetic (1.1 units of energy for lactation) concentrates: 1) high crude protein (cp) with rolled barley (hp, 19% cp); b) low cp wit ...201222818468
forage-based dairying in a water-limited future: use of models to investigate farming system adaptation in southern australia.the irrigated dairy industry in southern australia has experienced significant restrictions in irrigation water allocations since 2005, consistent with climate change impact predictions for the region. simulation models of pasture growth (dairymod), crop yield (agricultural production systems simulator, apsim), and dairy system management and production (udder) were used in combination to investigate a range of forage options that may be capable of sustaining dairy business profitability under r ...201222720972
ruminal protozoal contribution to the duodenal flow of fatty acids following feeding of steers on forages differing in chloroplast content.ruminant products are criticised for their sfa content relative to pufa, although n-6:n-3 pufa is desirable for human health ( < 4). rumen protozoa are rich in unsaturated fatty acids due to engulfment of pufa-rich chloroplasts. increasing the chloroplast content of rumen protozoa offers a potentially novel approach to enhance pufa flow to the duodenum and subsequent incorporation into meat and milk. we evaluated protozoal contribution to duodenal n-3 pufa flow due to intracellular chloroplast c ...201222377337
intensive cattle grazing affects pasture litter-fall: an unrecognized nitrous oxide source.the rationale for this study came from observing grazing dairy cattle dropping freshly harvested plant material onto the soil surface, hereafter called litter-fall. the intergovernmental panel on climate change (ipcc) guidelines include no emissions during pasture renewal but do not consider no emissions that may result from litter-fall. the objectives of this study were to determine litter-fall rates and to assess indicative no emission factors (efs) for the dominant pasture species (perennial ...201322370407
effect of rumen fill on intake of fresh perennial ryegrass in young and mature dairy cows grazing or zero-grazing fresh perennial ryegrass.rumen fill may be a strong intake constraint for dairy cows fed on pasture, even though pasture is highly digestible in the grasslands of temperate climates. this constraint may also depend on the cows' maturity. moreover, indoor feeding of fresh herbage may not always be a good model for the study of intake regulation at grazing. to test these hypotheses, four mature (6.3 ± 0.72 year old) and four young (3.8 ± 0.20 year old) dairy cows were offered fresh perennial ryegrass indoors or at grazing ...200922443555
digestion during continuous culture fermentation when replacing perennial ryegrass with barley and steam-flaked corn.the objective of this study was to quantify the optimal inclusion rate of grain required to maximize nutrient digestion of a diet based on highly digestible pasture. it was hypothesized that maximum digestion would occur at a rate of grain inclusion that resulted in a culture ph of 6.0, reflecting the ph below which fiber digestion would be expected to be compromised. four dual-flow continuous culture fermenters were used to establish the effects on digestion of replacing freeze-dried, highly di ...200919109278
grazing behaviour and performance of lactating suckler cows, ewes and goats on partially improved heathlands.the foraging behaviour (grazing time and diet composition), live-weight (lw) changes and parasitic infection (faecal egg counts of gastrointestinal nematodes) of 12 beef cows, 84 ewes and 84 goats suckling their offspring, managed in mixed grazing on heathlands with 24% of improved pasture of perennial ryegrass-white clover, were studied during the years 2003 and 2006. the results showed that goats tended to graze for a longer time, and utilised significantly more heathland vegetation than cattl ...200822444089
effects of dietary sulphur sources on concentrations of hydrogen sulphide in the rumen head-space gas of dairy cows.three change-over design experiments investigated the origin of hydrogen sulphide in the rumen head-space gas of dairy cows, comparing the effects of single iso-s additions of methionine, cysteine and sodium sulphate, as well as the effects of single meals of fresh ryegrass or white clover. the concentration of hydrogen sulphide in rumen gas declined close to zero within 4 h after withdrawal of the previous feed. sulphur sources were then given to cows and concentrations of hydrogen sulphide rec ...200722444410
feeding value of pastures for ruminants.perennial ryegrass is the primary forage component of ruminant diets in new zealand. it is persistent and palatable, and immature ryegrass has a high nutritive value (nv). however, seedhead development substantially lowers its feeding value (fv) as fibre concentration increases, the rate and extent of digestibility decreases, and voluntary intake declines. ryegrass pastures are susceptible to accumulation of endophytic and saprophytic fungi in dead material at the base of the sward, especially w ...200415768132
enhanced phytoextraction of uranium and selected heavy metals by indian mustard and ryegrass using biodegradable soil amendments.the applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (u), cadmium (cd), chromium (cr), copper (cu), lead (pb) and zinc (zn) by indian mustard (brassica juncea) and ryegrass (lolium perenne) was tested in a greenhouse experiment. plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of u. treatments with citric acid, nh4-citrate/citric acid, oxalic acid, s,s-ethylenediamine disuccinic acid (e ...200919054545
impact of brassica and lucerne finishing feeds and intramuscular fat on lamb eating quality and flavor. a cross-cultural study using chinese and non-chinese australian consumers.use of forage brassicas (brassica napus) and lucerne (alfalfa; medicago sativa) as ruminant feeds has been linked to unacceptable flavors in sheepmeat. lambs from low and high intramuscular fat sires were allocated to one of four finishing feeds-perennial ryegrass (lolium perenne), lucerne, and two brassica forages-for a 6 week period. grilled loins (longissimus thoracis et lumborum) were subjected to chemical and sensory analysis by a trained panel and also evaluated by non-chinese and chinese ...201627523884
phytoextraction for clean-up of low-level uranium contaminated soil evaluated.spills in the nuclear fuel cycle have led to soil contamination with uranium. in case of small contamination just above release levels, low-cost yet sufficiently efficient remedial measures are recommended. this study was executed to test if low-level u contaminated sandy soil from a nuclear fuel processing site could be phytoextracted in order to attain the required release limits. two soils were tested: a control soil (317 bq 238u kg(-1)) and the same soil washed with bicarbonate (69 bq 238u k ...200415162854
nitrous oxide emission factors for urine and dung from sheep fed either fresh forage rape (brassica napus l.) or fresh perennial ryegrass (lolium perenne l.).in new zealand, agriculture is predominantly based on pastoral grazing systems and animal excreta deposited on soil during grazing have been identified as a major source of nitrous oxide (n2o) emissions. forage brassicas (brassica spp.) have been increasingly used to improve lamb performance. compared with conventional forage perennial ryegrass (lolium perenne l.), a common forage in new zealand, forage brassicas have faster growth rates, higher dry matter production and higher nutritive value. ...201525407839
lambs fed fresh winter forage rape (brassica napus l.) emit less methane than those fed perennial ryegrass (lolium perenne l.), and possible mechanisms behind the difference.the objectives of this study were to examine long-term effects of feeding forage rape (brassica napus l.) on methane yields (g methane per kg of feed dry matter intake), and to propose mechanisms that may be responsible for lower emissions from lambs fed forage rape compared to perennial ryegrass (lolium perenne l.). the lambs were fed fresh winter forage rape or ryegrass as their sole diet for 15 weeks. methane yields were measured using open circuit respiration chambers, and were 22-30% smalle ...201525803688
enrichment of aliphatic, alicyclic and aromatic acids by oil-degrading bacteria isolated from the rhizosphere of plants growing in oil-contaminated soil from kazakhstan.three microbial strains were isolated from the rhizosphere of alfalfa (medicago sativa), grass mixture (festuca rubra, 75 %; lolium perenne, 20 %; poa pratensis, 10 %), and rape (brassica napus) on the basis of their high capacity to use crude oil as the sole carbon and energy source. these isolates used an unusually wide spectrum of hydrocarbons as substrates (more than 80), including n-alkanes with chain lengths ranging from c12 to c32, monomethyl- and monoethyl-substituted alkanes (c12-c23), ...201525592733
predicting molybdenum toxicity to higher plants: estimation of toxicity threshold values.four plant species (oilseed rape, brassica napus l.; red clover, trifolium pratense l.; ryegrass, lolium perenne l.; and tomato, lycopersicon esculentum l.) were tested on ten soils varying widely in soil properties to assess molybdenum (mo) toxicity. a larger range (66-fold-609-fold) of added mo concentrations resulting in 50% inhibition of yield (ed50) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of mo toxic ...201020656390
metal accumulation in lolium perenne and brassica napus as affected by application of chitosans.the effects of chitosan, a fishery waste-based material, and its derivative glutaraldehyde cross-linked chitosan (chitosan-gla) on metal uptake by lolium perenne (perennial ryegrass) and brassica napus (rapeseed) were studied in a greenhouse pot experiment. metal uptake by perennial ryegrass was highly dependent on the rate of addition of the chitosans. low application rate (1% w/w) enhanced metal uptake, whereas 10% (w/w) addition decreased metal uptake. it was estimated that chitosan 1% (w/w) ...201222908653
evaluation of methods to measure differential 15n labeling of soil and root n pools for studies of root exudation.to study patterns of root exudation, the effectiveness of different techniques for in situ 15n labeling of brassica napus, centaurea jacea and lolium perenne with ammonium nitrate was tested. stem infiltration was found to effectively label plants with thicker stems, whereas, for grass species, cutting and immersing the leaf tips into 15n solution proved to be most effective. a microdiffusion technique to isolate ammonium, combined with conventional cation-exchange chromatography to separate nit ...200415386635
conventional crops and organic amendments for pb, cd and zn treatment at a severely contaminated site.the ability of selected plants and amendments to treat pb, cd and zn accumulations from a metalliferous waste disposal site was studied both in the greenhouse and field. spinach (spinacea oleracea), cabbage (brassica oleracea), and a grass-legume mix (red fescue, festuca rubra; ryegrass, lolium perenne); and bean (vicia faba) were grown in the greenhouse on blast furnace slag or baghouse dust amended with composted peat (cp). all plant species accumulated pb, cd and zn to varying degrees. total ...200817475483
phytotoxic effects of sewage sludge extracts on the germination of three plant species.in order to evaluate the ability of three types of extracts to explain the ecotoxicological risk of treated municipal sewage sludges, the oecd 208a germination test was applied using three plants (lolium perenne l., brassica rapa l., and trifolium pratense l.). three equivalent batches of sludge, remained as dewatered sludge, composted with plant remains and thermally dried, from an anaerobic waste water treatment plant were separated. samples from these three batches were extracted in water, me ...200818651217
morphological variation in different host populations of abacarus hystrix (acari: prostigmata: eriophyoidea).the present systematic classification of eriophyoidea is widely recognised as artificial and not reflecting plant-herbivore linkage. quantitative description of host-related morphological variation can provide the basic information needed to improve the eriophyoid taxonomic system and enhance our understanding of mechanisms generating this variation. the purpose of this study was to investigate quantitative morphological traits of populations of cereal rust mite abacarus hystrix (nalepa 1896) li ...200212537292
accumulation of hmx (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) in indigenous and agricultural plants grown in hmx-contaminated anti-tank firing-range soil.to investigate their potential for phytoremediation, selected agricultural and indigenous terrestrial plants were examined fortheir capacity to accumulate and degrade the explosive octahydro-1 ,3,5,7-tetra nitro-1,3,5,7-tetrazocine (hmx). plant tissue and soil extracts were analyzed for the presence of hmx and possible degradative metabolites using high-performance liquid chromatography with diode-array uv detection (hplc-uv), micellar electrokinetic chromatography with diode-array uv detection ...200211811476
cross-reactive and unique grass group i antigenic determinants defined by monoclonal antibodies.as part of a study to probe the immunochemical basis for allergenic cross-reactivity among grass pollens, a series of useful reagents has been prepared. the major grass-pollen allergen, designated group i (gpi), was isolated from five grass pollens (meadow fescue, june grass, sweet vernal grass, redtop grass, and perennial ryegrass). the purified gpi antigens were used to immunize individual groups of balb/c mice. a total of 123 hybridoma-derived anti-gpi monoclonal antibodies (mabs) was produce ...19872434551
evaluation of long-chain alcohols as diet composition markers in goats grazing heathland areas.an experiment was conducted to assess the potential of long-chain alcohols (lcoh), in alternative or combined with alkanes and long-chain fatty acids (lcfa), as faecal markers to estimate the diet composition of goats grazing heathland vegetation with associated improved pastures. a total of seven diets were offered across the grazing season. the diets were composed of mixtures of herb species (lolium perenne and trifolium repens) and woody species (erica spp., calluna vulgaris and ulex gallii) ...201222436286
antioxidant responses in carassius auratus and lolium perenne exposed to the laboratory pollution.experiments conducted in the laboratories can produce numerous wastes, which could potentially affect the health of the researchers. in this study, the antioxidant responses in liver of carassiua auratus and leaf of lolium perenne were investigated after chronic exposure to the air pollution in four different laboratories. the obtained data showed that oxidative stress was induced in some laboratories, as indicated by some significantly altered biochemical parameters. additionally, the toxicity ...201424561535
leaf economics spectrum-productivity relationships in intensively grazed pastures depend on dominant species identity.plant functional traits are thought to drive variation in primary productivity. however, there is a lack of work examining how dominant species identity affects trait-productivity relationships. the productivity of 12 pasture mixtures was determined in a 3-year field experiment. the mixtures were based on either the winter-active ryegrass (lolium perenne) or winter-dormant tall fescue (festuca arundinacea). different mixtures were obtained by adding forb, legume, and grass species that differ in ...201627092237
fatty acids, α-tocopherol, β-carotene, and lutein contents in forage legumes, forbs, and a grass-clover mixture.fresh forages are an important natural source of vitamins and fatty acids in ruminant diets, and their concentrations in forage species are important for the quality of animal-derived foods such as dairy and meat products. the aims of this study were to obtain novel information on vitamins and fatty acids (fa) in a variety of forage legumes and non-legume forb species compared to a grass-clover mixture and to explore implications for animal-derived products. seven dicotyledons [four forbs (salad ...201324262011
shifts in abundance and diversity of soil ammonia-oxidizing bacteria and archaea associated with land restoration in a semi-arid ecosystem.the grain to green project (ggp) is an unprecedented land restoration action in china. the project converted large areas (ca 10 million ha) of steep-sloped/degraded farmland and barren land into forest and grassland resulting in ecological benefits such as a reduction in severe soil erosion. it may also affect soil microorganisms involved in ammonia oxidization, which is a key step in the global nitrogen cycle. the methods for restoration that are typically adopted in semi-arid regions include a ...201526172994
a comparison of manometric and membrane-electrode procedures for measuring rates of leaf decay.two instruments were compared for consistency of decay-rate measurements of four leaf types: lolium perenne, typha domingenesis, casuarina cunninghamiana and eucalyptus polyanthemos, via progressive biological oxygen demand (bod). the instruments were (a) a dissolved oxygen probe (i.e. an oxygen-selective membrane electrode) used in two different modes: (1) measurements of sacrificial samples that were successively discarded, and (2) repeated measurements of the same sample, and (b) a mercury fr ...200111349381
interrelations between herbage yield, α-tocopherol, β-carotene, lutein, protein, and fiber in non-leguminous forbs, forage legumes, and a grass-clover mixture as affected by harvest date.pastures with diverse botanical composition may enhance animal-derived product quality. a recent study demonstrated high vitamin concentrations and yields in some forb species. the objectives of the present study were to investigate interrelations between herbage yields, vitamin concentrations, protein and fiber contents and analyze the effect of harvest date. we hypothesized that interrelations would be similar across investigated forage species. four nonleguminous forbs: salad burnet (sanguiso ...201525573460
direct fermentation of fodder maize, chicory fructans and perennial ryegrass to hydrogen using mixed microflora.this study examined the feasibility of producing hydrogen by direct fermentation of fodder maize, chicory fructooligosaccharides and perennial ryegrass (lolium perenne) in batch culture (ph 5.2-5.3, 35 degrees c, heat-treated anaerobically digested sludge inoculum). gas was produced from each substrate and contained up to 50-80% hydrogen during the peak periods of gas production with the remainder carbon dioxide. hydrogen yields obtained were 62.4+/-6.1ml/g dry matter added for fodder maize, 218 ...200818513959
how interacting fungal species and mineral nitrogen inputs affect transfer of nitrogen from litter via arbuscular mycorrhizal mycelium.in the karst landscape, widespread in the world including southern china, soil nutrient supply is strongly constrained. in such environments, arbuscular mycorrhizal (am) fungi may facilitate plant nutrient uptake. however, the possible role of different am fungal species, and their interactions, especially in transferring nitrogen (n) from litter to plant, is poorly understood. we conducted two microcosm experiments to investigate the role that two karst soil am fungi, glomus etunicatum and glom ...201728258426
aboveground endophyte affects root volatile emission and host plant selection of a belowground insect.plants emit specific blends of volatile organic compounds (vocs) that serve as multitrophic, multifunctional signals. fungi colonizing aboveground (ag) or belowground (bg) plant structures can modify voc patterns, thereby altering the information content for ag insects. whether ag microbes affect the emission of root volatiles and thus influence soil insect behaviour is unknown. the endophytic fungus neotyphodium uncinatum colonizes the aerial parts of the grass hybrid festuca pratensis × lolium ...201525284612
energy efficiency and energy homeostasis as genetic and epigenetic components of plant performance and crop productivity.the importance of energy metabolism in plant performance and plant productivity is conceptually well recognized. in the eighties, several independent studies in lolium perenne (ryegrass), zea mays (maize), and festuca arundinacea (tall fescue) correlated low respiration rates with high yields. similar reports in the nineties largely confirmed this correlation in solanum lycopersicum (tomato) and cucumis sativus (cucumber). however, selection for reduced respiration does not always result in high ...201121411363
confirmation of the airborne occurrence of micron-size airborne pollen antigen carrying particles by immunoblotting.we confirmed the existence of micron-size airborne particles carrying major pollen antigen of cryptomeria japonica (cry j l) and lolium perenne (lol p l) by means of an immunoblotting technique and examination by light microscopy. the size of the spots on a nitrocellulose membrane, marking the presence of antigen on the sampler's tape, varied considerably under light microscopic examination. spots smaller than pollen grains and micron-size spots were observed together with large spots which seem ...19938489692
determination of the uptake of [pt(nh3)4](no3)2 by grass cultivated on a sandy loam soil and by cucumber plants, grown hydroponically.two cultivation experiments were carried out in order to answer the question to what extent platinum can enter the food chain by accumulation in plants, when the platinum is present in a bio-available form: (i) cucumber plants (cucumis sativus) were grown hydroponically in nutrient solutions containing [pt(nh3)4](no3)2 (from 0.5 to 50 micrograms pt/l solution); and (ii) a water-soluble platinum compound--[pt(nh3)4](no3)2--was added in increasing amounts to a sandy loam soil (from 0.5 to 50 mg pt ...19989753790
[effects of three industrial organic wastes as amendments on plant growth and the biochemical properties of a pb/zn mine tailings].a field trial was conducted in an abandoned pb/zn mine tailings to evaluate the effectiveness of three industrial wastes [sweet sorghum vinasse (ssv), medicinal herb residues (mhr) and spent mushroom compost (smc)] as organic amendments on plant growth, soil nutrients and enzyme activities, and heavy metal concentrations in plant tissues and the mine tailings. (1) the main findings were as follows: (1) the mean concentrations of diethylene-triamine-pentaacetic acid (dtpa)-extractable cd, cu, pb ...201627078971
comparing dislodgeable 2,4-d residues across athletic field turfgrass species and time.2,4-dimethylamine salt (2,4-d) is an herbicide commonly applied on athletic fields for broadleaf weed control that can dislodge from treated turfgrass. dislodge potential is affected by numerous factors, including turfgrass canopy conditions. building on previous research confirming herbicide-turfgrass dynamics can vary widely between species, field research was initiated in 2014 and 2015 in raleigh, nc, usa to quantify dislodgeable 2,4-d residues from dormant hybrid bermudagrass (cynodon dactyl ...201627936174
the appreciation of mineral element accumulation level in some herbaceous plants species by icp-aes method.from the metallurgic industry zone of dambovita county, we harvested and analyzed seven herbaceous plants species (lolium perenne, festuca pratensis, stipa capillata, agrostis alba, cynodon dactylon, luzula campestris, and agrostis tenuis) to establish the heavy metal accumulation levels in these species.201020165925
screening of pahs and ddts in sand and acrisols soil by a rapid solid-phase microalgal bioassay.previously we have demonstrated the rapid screening potential of a newly developed solid-phase microalgal bioassay with spiked sands. in this paper, we report further comparative results using both pahs and ddts spiked sands and field-collected acrisols soils. toxicity responses obtained from standard higher plant tests with three species of plants (lolium perenne, cynodon dactylon and brassica chinensis) were compared with those obtained from a cocktail of microalgae (selenastrum capricornutum, ...200717503178
functional immunoglobulin e cross-reactivity between pas n 1 of bahia grass pollen and other group 1 grass pollen allergens.grass pollens are major triggers of allergic rhinitis and asthma, but the immunological relationships between pollen allergens of the subtropical bahia grass, paspalum notatum, and temperate grasses are unresolved.201121231976
subtropical grass pollen allergens are important for allergic respiratory diseases in subtropical regions.grass pollen allergens are a major cause of allergic respiratory disease but traditionally prescribing practice for grass pollen allergen-specific immunotherapy has favoured pollen extracts of temperate grasses. here we aim to compare allergy to subtropical and temperate grass pollens in patients with allergic rhinitis from a subtropical region of australia.201222409901
prevalence of pollinosis in patients with allergic asthma, rhinitis and conjunctivitis in the south of mexico city 2007-2013.the prevalence of pollinosis has doubled in the past two decades. several studies suggest that up to 50% of adult residents of mexico city can present manifestations of respiratory allergy, and pollens from trees, grasses and weeds are a common cause. to determine the prevalence of their families and antigenic cross-reactivity allows us to offer appropriate diagnoses and treatments.201725177850
construction of high-density genetic linkage map and identification of flowering-time qtls in orchardgrass using ssrs and slaf-seq.orchardgrass (dactylis glomerata l.) is one of the most economically important perennial, cool-season forage species grown and pastured worldwide. high-density genetic linkage mapping is a valuable and effective method for exploring complex quantitative traits. in this study, we developed 447,177 markers based on slaf-seq and used them to perform a comparative genomics analysis. perennial ryegrass sequences were the most similar (5.02%) to orchardgrass sequences. a high-density linkage map of or ...201627389619
application of image analysis for grass tillering determination.tillering is defined as the process of above-ground shoot production by a single plant. the number of grass tillers is one of the most important parameters in ecology and breeding studies. the number of tillers is usually determined by manually counting the separated shoots from a single plant. unfortunately, this method is too time-consuming. in this study, a new method for counting grass tillers based on image analysis is presented. the usefulness of the method was evaluated for five grass spe ...201526446128
the grass pollen season 2014 in vienna: a pilot study combining phenology, aerobiology and symptom data.grasses (poaceae) are one of the largest plant families and are distributed worldwide. grass pollen allergy is one of the most important pollen allergies affecting large parts of the population worldwide. the grass pollen season itself is special since it is caused by the flowering of various grass species that present unique profiles of allergenicity, which assumingly plays a significant role and impact on grass pollen sensitization profiles for the allergy sufferer. the aim of this study, cond ...201627317132
bacterial endophyte communities of three agricultural important grass species differ in their response towards management regimes.endophytic bacteria are critical for plant growth and health. however, compositional and functional responses of bacterial endophyte communities towards agricultural practices are still poorly understood. hence, we analyzed the influence of fertilizer application and mowing frequency on bacterial endophytes in three agriculturally important grass species. for this purpose, we examined bacterial endophytic communities in aerial plant parts of dactylis glomerata l., festuca rubra l., and lolium pe ...201728102323
impact of grassland management regimes on bacterial endophyte diversity differs with grass species.most plant species are colonized by endophytic bacteria. despite their importance for plant health and growth, the response of these bacteria to grassland management regimes is still not understood. hence, we investigated the bacterial community structure in three agricultural important grass species dactylis glomerata l., festuca rubra l. and lolium perenne l. with regard to fertilizer application and different mowing frequencies. for this purpose, above-ground plant material was collected from ...201626834040
zymoseptoria ardabiliae and z. pseudotritici, two progenitor species of the septoria tritici leaf blotch fungus z. tritici (synonym: mycosphaerella graminicola).zymoseptoria is a newly described genus that includes the prominent wheat pathogen zymoseptoria tritici (synonyms mycosphaerella graminicola and septoria tritici). studies indicated that the center of origin of z. tritici is in the middle east where this important pathogen emerged during the domestication of wheat. several zymoseptoria species have been found on uncultivated grasses in the middle east, and in this article we describe two new zymoseptoria species from iran. these species, isolate ...201222675045
comparison of a colorimetric and a high-performance liquid chromatography method for the determination of fructan in pasture grasses for horses.pasture (fresh or conserved as hay/haylage) forms the basis of most equid diets and contains varying amounts (0 to ≥ 200 g kg⁻¹ dry matter (dm) or more) of fructans. over-consumption of fructan is associated with the onset of laminitis in equids, an agonizing condition that may necessitate euthanasia. to enable appropriate dietary management of animals susceptible to laminitis, it is essential that fructans can be properly quantified in fresh and conserved pasture. for research purposes, fructan ...201222297902
uptake and transformation of soil [14c]-trinitrotoluene by cool-season grasses.this study investigated the fate and uptake of [(14)c]-tnt from soil into orchardgrass (dactylis glomerata), perennial ryegrass (lolium perenne), and tall fescue (festuca arundinacea) over a one year period in a greenhouse-controlled environment. pots (n = 4 for each grass, containing 10 mg cold tnt/kg soil + 1.2 mg [(14)c]-tnt/kg soil and controls with no tnt) were exposed to light and temperature conditions typical of june at 45 degrees n for 369 days. three plant harvests were made (63, 181, ...201020666491
characterization of allergenic epitopes of ory s1 protein from oryza sativa and its homologs.vaccination is the most effective technique suggested now days for allergy treatment. recombinant-based approaches are mostly focused on genetic modification of allergens to produce molecules with reduced allergenic activity and conserved antigenicity. the molecules developed for vaccination in allergy possess significantly reduced allergenicity in terms of ige binding, and therefore will not lead to anaphylactic reactions upon injection. this approach is probably feasible with every peptide all ...200920011147
biodiversity effects on yield and unsown species invasion in a temperate forage ecosystem.current agricultural practices are based on growing monocultures or binary mixtures over large areas, with a resultant impoverishing effect on biodiversity at several trophic levels. the effects of increasing the biodiversity of a sward mixture on dry matter yield and unsown species invasion were studied.200919168861
cross-species amplification tests and diversity analysis using 56 pcr markers in dactylis glomerata and lolium perenne.we report results of cross-species amplification in dactylis glomerata and lolium perenne of 12 simple sequence repeats (ssrs) isolated from lolium multiflorum×festuca glaucescens, 42 ssrs from festuca arundinacea and two sequence tagged sites from oryza sativa. we compared the transferability and diversity between d. glomerata and l. perenne, which are important forage crops. while nei's gene diversity values were equivalent in both species (from 0.14 to 0.92), the mean number of allele per loc ...200921564590
fractional and structural characterization of hemicelluloses from perennial ryegrass (lolium perenne) and cocksfoot grass (dactylis glomerata).sequential three-stage treatments with 80% etoh containing 0.2% naoh, 2.5% h2o2-0.2% edta containing 1.5% naoh and 2.5% h2o2-0.2% taed containing 1.0% naoh at 75 degrees c for 3h released 8.0% and 10.4%, 79.1% and 77.0% and 12.9% and 12.5% of the original hemicelluloses from perennial grass and cocksfoot grass, respectively. it was found that the four alkaline peroxide-soluble hemicellulosic fractions contained higher amounts of xylose (33.4-38.2%), uronic acids (9.3-15.3%) and rhamnose (3.0-3.9 ...200616750181
herbaceous vegetation productivity, persistence, and metals uptake on a biosolids-amended mine soil.the selection of plant species is critical for the successful establishment and long-term maintenance of vegetation on reclaimed surface mined soils. a study was conducted to assess the capability of 16 forage grass and legume species in monocultures and mixes to establish and thrive on a reclaimed appalachian surface mine amended with biosolids. the 0.15-ha coarse-textured, rocky, non-acid forming mined site was prepared for planting by grading to a 2% slope and amending sandstone overburden ma ...201216151233
differential effects of light quality, provided by different grass neighbours, on the growth and morphology of trifolium repens l. (white clover).the ability to respond in a specific manner to different light conditions imposed by different species of grass is a major factor contributing to white clover persistence in pastures. gaps in a pasture provide light with a higher red:far-red ratio (r:fr) and higher photosynthetic photon flux density (ppfd) than the light filtered through neighbours. white clover (trifolium repens l.) was grown under different light conditions in ways that tried to simulate as closely as possible some of the ligh ...200024595840
[specific skin reactions induced by individual pollen preparations in hypersensitivity persons].skin tests are the most useful single modality for demonstrating an ige-mediated mechanism underlying clinical symptoms. skin reactivity to an allergen depends on person's exposure and genetic factors influencing the ige response. however, the reproducibility of allergy skin tests has been shown to be variable depending, among other things, on the allergen extract employed and the kind of technique used. these variations have led to controversy regarding clinical relevancy of allergy skin testin ...20099863408
long-term responsiveness to free air co2 enrichment of functional types, species and genotypes of plants from fertile permanent grassland.to test inter- and intraspecific variability in the responsiveness to elevated co2, 9-14 different genotypes of each of 12 perennial species from fertile permanent grassland were grown in lolium perenne swards under ambient (35 pa) and elevated (60 pa) atmospheric partial pressure of co2 (pco2) for 3 years in a free air carbon dioxide enrichment (face) experiment. the plant species were grouped according to their functional types: grasses (l. perenne, l. multiflorum, arrhenatherum elatius, dacty ...199728307292
cloning, sequencing and immunological characterization of dac g 3, a major allergen from dactylis glomerata pollen.preliminary work showed that a 14-kda allergen with a pi of 9 was recognized by more than 60% of sera from dactylis glomerata (dac g) pollen-allergic individuals. the n-terminal amino acid sequence of this dac g allergen was determined by edman degradation and compared with that of lol p 3, a major allergen of lolium perenne. a sequence identity of 65% was found, suggesting that the dac g allergen could be the homologue of lol p 3 and therefore named dac g 3. we report the cloning and sequence a ...19968811075
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