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At least 19 recordsLinked to original sources
PubMed1992

In situ degradability of fresh grass and grass conserved under different harvesting methods.

The effects of forage conservation and harvesting method on DM and CP degradability of grass cut at the boot stage were determined using nylon bags incubated in the rumen of two fistulated lactating cows. Samples of fresh grass, wilted grass prior to and after ensiling in a stack silo and cut with either a cylinder-type forage harvester (11.3 mm of length cut) or a self-loading wagon (42.4 mm of length cut), wilted grass prior to and after ensiling in large round bales, and grass hay were obtained from the same field and used for determination of DM and CP degradability. The DM-soluble fraction of fresh grass was significantly lower than that of wilted grass and silage, but it was higher than that of hay. In general, the potentially degradable fraction of all treatments was related inversely to the readily soluble fraction in water. The effective degradability of DM of fresh grass was similar to that of hay but was lower than that of wilted grass and silage. The effective degradability of DM of silage was higher than that of wilted grass and hay. The disappearance rate of CP of fresh grass was similar to that of wilted grass, hay, and silage. Silage had a lower disappearance rate of CP than wilted grass. The effective degradability of CP was similar for fresh and wilted grasses. Protein degradability was greater for silages than for fresh and wilted grasses. Protein degradability of hay was similar to that of fresh grass and wilted grass.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1992

Diagnosis of grass pollen allergy with recombinant timothy grass (Phleum pratense) pollen allergens.

In order to establish a test system for grass pollen allergy based on the use of recombinant allergens we chose timothy grass (Phleum pratense), a widely spread grass, as a model. From a lambda gt11 cDNA expression library that we had constructed from pollen RNA of timothy grass (P. pratense), we had obtained with serum IgE from a grass pollen-allergic individual 60 IgE-binding clones. By differential testing with sera from different grass pollen-allergic patients, we selected three distinct clones encoding Phl p I (group I), Phl p V (group V) and profilin from timothy grass, which when used together allowed the diagnosis of grass pollen allergy in 97 out of 98 tested grass pollen-allergic patients employing a simple plaque lift technique. This recombinant test based on plaque lifts containing allergen-beta-galactosidase fusion proteins was compared with IgE immunoblots using crude pollen protein extracts from timothy grass. Both methods were in good agreement with RAST scores and clinical data, and proofed to be useful for the diagnosis of grass pollen allergy. Our results further indicate that a limited panel of only two recombinant grass pollen allergens, Phl p I and Phl p V, together with the plant panallergen profilin could be sufficient for the diagnosis and possibly immunotherapy of grass pollen allergy.

Adolescent↗
PubMed1979

Species specific grass pollen sensitivity: diagnosis and treatment with single grass species Allpyral vaccines.

Skin test titrations and nasal provocation tests in sixty patients with hay fever showed specific reactions to extracts of individual grass species. There was, however, no correlation between skin and nasal sensitivity. Repeat testing after treatment with Allpyral vaccines consisting of only the grass species to which the nasal reaction was most severe, or only one of several pollens to which reactions were equally severe, showed marked diminution of skin and nasal sensitivity not only to the single pollen used for immuno-therapy but to all five common pollens used in the Allpyral grass mix. Clinical results seemed much improved as compared with results in the same year for Allpyral five grass mix vaccines, especially in the case of patients treated with Timothy, rye, or cocksfoot. It was concluded that these three grassees were to be preferred for treatment in England, and that these grasses contain common allergens.

Dose-Response Relationship, Immunologic↗
PubMed1991

Group V allergens in grass pollens. II. Investigation of group V allergens in pollens from 10 grasses.

In an earlier study an allergen from Phleum pratense (timothy) pollen, Phl p V, has been isolated and physicochemically characterized. In this study Phl p V and immunochemically similar components from other grass pollens (group V allergens) have been investigated using immunoelectrophoretic techniques. To study the allergenic importance of the group V allergens, the allergenic compositions of 10 grass pollen extracts were investigated in crossed radioimmunoelectrophoresis (CRIE) using 20 sera from grass pollen-allergic donors. Group V allergens were identified using monospecific rabbit antibodies raised against Phl p V, anti-Phl p V, which react with other group V allergens usually producing dense precipitates in immunoelectrophoresis. In this way group V allergens were identified in eight extracts, and when present the precipitate corresponding to the group V allergen was the dominant IgE binding precipitate. All identified group V allergens bound IgE in at least 17 of the 20 investigated sera. Monospecific rabbit antibodies raised against the group I allergen of Lolium perenne (rye grass), anti-Lol p I, do not precipitate group V allergens, indicating that there are no immunochemical similarities between group I and group V allergens. In SDS-PAGE anti-Phl p V identifies IgE-binding components with molecular weights between 26 and 33 kD. In contrast, anti-Lol p I binds to components of slightly higher molecular weight. Apparently, the group V components are allergens that are physicochemically and immunochemically distinct from group I allergens.

Allergens↗
PubMed1992

Clinical and immunological effects of immunotherapy with alum-absorbed grass allergoid in grass-pollen-induced hay fever.

A double-blind, placebo-controlled study of immunotherapy was conducted in 19 patients with grass-pollen hay fever to evaluate the efficacy and safety of a formalinized depot grass allergoid. The patients were assessed before and during IT by clinical (symptom-medication scores during the grass- pollen season, specific nasal and skin reactivity) and immunological (specific IgE, IgG, IgG1 and IgG4 antibodies) parameters. High doses of grass allergoid, corresponding to a cumulative pre-seasonal dosage of 46,050 PNU, were administered, with only one systemic reaction. The actively treated patients had significantly lower symptom-medication scores than placebo (p less than 0.01) during the month of May and showed a significant decrease in specific skin (p less than 0.01) and nasal (p less than 0.05) reactivity, and a significant early increase in specific IgE (p less than 0.01), IgG (p less than 0.0005), IgG1 (p less than 0.001) and IgG4 (p less than 0.05), with a subsequent decrease of IgE and IgG1. No differences were detected in any of these parameters in the placebo group. A correlation was found between high IgG4/IgG1 ratio and the specific skin reactivity decrease (r = 0.691, p less than 0.05), whereas a high IgG4/IgG1 ratio was associated with higher symptom-medication scores (r = 0.654, p less than 0.05). Possible explanations of these apparent discrepancies are proposed.

Adolescent↗
PubMed1978

The nutritive value of silages. Energy metabolism in sheep receiving diets of grass silage or grass silage and barley.

1. Two calorimetric experiments were conducted to study the utilization of energy in sheep given diets of grass silage or grass silage and barley. Three silages were investigated. One was made from first-harvest grass in the spring (S) and the others from regrowth cut either early or late in the autumn (E and L respectively). All were of perennial ryegress (Lolium perenne) and preserved with formic acid. Each silage was given at two levels of feeding, the lower providing approximately a maintenance energy intake. The S and L silages were also given supplemented with barley. 2. The digestibilities of organic matter, cellulose and energy in the silages were high. Measured at maintenance, digestible energy (DE) contents (MJ/kg dry matter (DM))were 11.83, 14.67 and 12.90 for S, E and L respectively. The DE contents of the S and E silages were depressed at the higher level of feeding but the effect was offset by changes in the energy losses as methane and urine. Metabolizable energy (ME) contents (MJ/kg DM) for the three silages, S, E and L were respectively 9.88, 12.54 and 10.73 at the low level of feeding and 9.91, 11.99 and 11.08 at the high level of feeding. The mean ME content of barley calculated by difference was 13.76 MJ/kg DM. 3. The mean efficiencies of utilization of ME for maintenance (km) for the S, E and L silages were 0.69, 0.71 and 0.68 respectively. Corresponding values for fattening (kf) were 0.21, 0.57 and 0.59. Excepting the kf for the S silage which was low, observed efficiencies were in broad agreement with those predicted by the equations of the Agricultural Research Council (1965). Similar agreement was obtained with all diets consisting of silage and barley.

Animal Feed↗
PubMed1978

A comparative study of an aqueous grass pollen extract and glutaraldehyde-treated grass pollen-tyrosine adsorbate in the treatment of pollenosis.

Hyposensitization therapy gave a subjective improvement in 84% of grass pollen-sensitive patients receiving an eighteen dose course of aqueous pollen extract (SDV) and in 69% of patients receiving a three dose course of glutaraldehyde-treated pollentyrosine adsorbate (Pollinex). Systemic reactions to treatment were considerably more frequent with the aqueous course, but virtually absent with the short adsorbate course, which seems therefore more convenient for the patient. The SDV treatment induced a more pronounced IgG antibody response both in patients and in guinea-pigs receiving the clinical dosage schedule. The Pollinex treatment showed a tendency to enhance the IgE antibody response in new patients.

Adult↗
PubMed1976

Chemical modification of crude timothy grass pollen extract. II. Class and specificity of antibodies induced by chemically modified timothy grass pollen extract.

The effects have been studied of three different chemical modifications of timothy grass pollen extract on various immunological properties. The ability to induce IgG antibody with specificity for native antigen was least affected by glutaraldehyde treatment; IgE antibody production was reduced to a similar extent by all three modifications; there was no increase in IgM production; delayed reactions were reduced. New antigenic determinants were introduced by all the modifications, but the effect was minimal following glutaraldehyde treatment. The significance of these results and the potential application of modified allergen in hyposensitisation therapy are discussed.

Acetoacetates↗
PubMed1976

The cross-reactivity of IgE antibodies with pollen allergens. I. Analyses of various species of grass pollens.

Atopic patients with histories of grass pollen allergy often are sensitive to a variety of species of grasses. Using a serum pool from patients sensitive to June grass, we analyzed the reactivity of IgE antibodies to seven grasses by the radioallergosorbent test. Extracts were analyzed for their inhibitory activities with solid-phase allergens prepared from all of the grass pollen. Also samples of serum were exhaustively absorved with solid-phase allergens and the supernatants tested to determine the reactivity of the remaining IgE antibodies. Three patterns of reactivity were observed: (1) June, orchard, meadow fescue, and perennial rye grasses displayed similar reactivity in both inhibition and absorption studies; (2) sweet vernal and Bermuda grasses were considerably less reactive with the serum pool, indicating that they lacked antigenic determinants possessed by the other grasses; and (3) timothy grass possessed unique antigenic determinants. Knowledge of these patterns of cross-allergenicity is of importance for diagnosis and treatment of sensitive patients as well as for in vitro standardization of extracts.

Absorption↗
PubMed1991

Differences in clinical and immunologic reactivity of patients allergic to grass pollens and to multiple-pollen species. II. Efficacy of a double-blind, placebo-controlled, specific immunotherapy with standardized extracts.

The IgE response of patients only allergic to grass pollens differs from response of patients allergic to multiple-pollen species. The IgE immunoblots to orchard-grass pollens confirmed that polysensitized patients had more proteins revealed than patients only allergic to grass pollens. To determine if both groups of patients present a different response toward specific immunotherapy (IT), a double-blind, placebo-controlled study was performed in 70 patients. Patients receiving the active treatment had a rush IT with either a standardized orchard grass-pollen extract or with a standardized mixed-pollen extract prepared, depending on the sensitivity of the patients. The maintenance dose was defined as that dose effective in grass-pollen IT in previous experiments. The same equipotent maintenance dose was administered for all pollen species. Symptom-medication scores during the pollen season and nasal challenge with orchard grass-pollen grains demonstrated that grass pollen-allergic patients had a significantly improved efficacy by comparison to placebo treatment, whereas polysensitized patients had a nonsignificant improvement. Serum grass-pollen IgG was significantly increased after IT in both treated groups. This study demonstrate that the response toward specific IT differs in patients only allergic to grass pollens by comparison to polysensitized patients.

Adolescent↗
PubMed1991

Selenium accumulation and selenium tolerance of salt grass from soils with elevated concentrations of Se and salinity.

Biomass production, selenium accumulation, and the role of the bioextraction of selenium by salt grass (Distichlis spicata L.) in soils with elevated concentrations of Se and salinity at Kesterson, California, were studied. Salt grass contributed more than 80% vegetative coverage and 90% dry weight in the grassland communities where the soil Se concentrations were 100 times (1000 to 3000 micrograms kg-1) higher than the Se concentrations found in soils of the control sites. No evidence for evolution of Se tolerance was found in the salt grass populations. The successful colonization of salt grass in the soil with elevated Se and salinity is attributable to the presence of high concentrations of soil sulfate. Salt grass accumulated less Se than other salt-tolerant plant species existing in the same area, and no predation of animals and insects on salt grass has been noticed. Salt grass can transpire substantial amounts of volatile Se through its plant tissue. Under field conditions, a 1-m2 salt grass plot may produce 180 micrograms volatile selenium per day. However, no reduction of soil Se concentration in the salt grass habitat was detected over a period of 1 year. A long-term monitoring of Se status is needed in order to make predictions of the effectiveness of efforts to clean up Se-contaminated soils through the use of native plant species.

Chlorides↗
PubMed1991

Acute phase proteins in grass sickness (equine dysautonomia).

Four acute phase proteins were assayed in the serum of normal horses and those with acute, subacute and chronic grass sickness, colic and inflammatory conditions, in order to investigate their diagnostic value in grass sickness. The grass sickness and inflammation group had a significantly increased haptoglobin concentration (P less than 0.01-P less than 0.001). Orosomucoid was elevated in acute, subacute and chronic grass sickness and inflammation (P less than 0.001, P less than 0.001, P less than 0.05 and P less than 0.05, respectively). Highest concentrations of haptoglobin and orosomucoid were recorded in subacute grass sickness. Ceruloplasmin was significantly higher in acute grass sickness cases than all other groups except the colic group (P less than 0.05-P less than 0.01). alpha 2-macroglobulin was significantly higher in acute grass sickness than normal, colic and chronic grass sickness cases (P less than 0.01, P less than 0.05 and P less than 0.05). The time scale of changes suggests that the stimulus to haptoglobin and orosomucoid synthesis occurs at the onset of clinical signs whereas the increase in ceruloplasmin and alpha 2-macroglobulin is more likely to reflect haemoconcentration.

Acute Disease↗
PubMed1977

Epichloë typhina from toxic tall fescue grasses.

Epichloë typhina, a clavicipitaceous systemic phytopathogen, was isolated from two varieties and three hybrids of tall fescue (Festuca arundinaceae). The morphology of the fescue isolates was compared with E. typhina isolated from bent grass (Agrostis perennans). In all isolates, conidia were identical and were typical of E. typhina. In fescue grasses the endophyte failed to produce stromata, but on bent grass the fungus seasonally produced stromata, typical of the genus. Cattle grazing the fescue grasses showed signs of the fescue toxicity syndrome, the E. typhina was found in frequencies of 100%; in grasses from pastures in which cattle showed no signs of the syndrome, frequencies were 0 to 50%. Nutritional factors in vitro were more complex for the isolates from fescue than for the isolate from bent grass. These studies suggested that E. typhina includes biotypes that might be involved in the toxicity syndrome. The fescue biotypes grew poorly on media, and yields were inadequate for toxicity studies. However, the bent grass isolate grew well on three media, and extracts from two of these were toxic to chicken embryos. All isolates produced in vitro the nontoxic fungal steroid tetraenone [ergosta-4,6,8(14),22-tetraen-3-one], which has been isolated from toxic fescue grasses.

Animals↗
PubMed1991

Allergenic and antigenic cross-reactivities of group IX grass pollen allergens.

The allergenic and antigenic cross-reactivities between a major recombinant Poa pratensis (Poa p) IX allergen, rKBG8.3, and its corresponding proteins of different grass pollens were examined. Immunoblotting of the proteins of thirteen different grass pollens using anti-rKBG8.3 antibodies indicated that Poa p IX-like proteins are present in ten other grass pollens, albeit in variable amounts and polymorphic forms. These proteins ranged in size from 20 to 88 kDa in different grass pollens. The percent relative binding determined for each grass pollen extract using allergic human sera showed a significant correlation (r = 0.891) with that of anti-rKBG8.3 antiserum. Moreover, there was a strong association (r = 0.901) between the Kentucky bluegrass extract and rKBG8.3 with respect to their inhibition of the binding of human IgE antibodies to allergens in grass pollen extracts. Taken together, these results suggest that the allergenic and antigenic epitopes of the Poa p IX-related proteins in some but not all grass pollens are similar in structure and specificities. It is concluded that the group IX allergens constitute a major family of homologous proteins in several grass pollens.

Allergens↗
PubMed1977

[Grass pollen in Munich air. Preparations for a forecast (author's transl)].

To forecast pollen concentrations of the air of a particular place the following data of the area in question should be known: The basic grass pollen content of the air from volumetric measurements made during several years and its mean seasonal changes; the mean daily grass pollen content of 1 m3 of air and its changes, especially at the beginning of the main grass pollen season; the influence of temperature, humidity, precipitation and wind speed on the grass pollen content; weather forecast of the day for which the pollen forecast is to be made and the grass pollen content of the previous day; the composition of the grass flora in the surroundings and the state of flowering of the main components of the grass flora. These data for the city of Munich are presented and discussed. In addition the grass pollen content in the air during the summers of 1975 and 1976 is compared with allergic complaints of 96 and 45 persons respectively.

Air Movements↗