Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “GRASSES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2002

Influence of livestock grazing on C sequestration in semi-arid mixed-grass and short-grass rangelands.

We evaluated the effects of livestock grazing on C content of the plant-soil system (to 60 cm) of two semi-arid grasslands: a mixed-grass prairie (grazed 12 years), and a short-grass steppe (grazed 56 years). Grazing treatments included season-long grazing at heavy and light stocking rates, and non-grazed exclosures. Significantly higher soil C (0-30cm) was measured in grazed pastures compared to non-grazed exclosures, although for the short-grass steppe higher soil C was observed with the heavy grazing treatment only. Excluding grazing caused an immobilization of C in excessive aboveground plant litter, and an increase in annual forbs and grasses which lack dense fibrous rooting systems conducive to soil organic matter formation and accumulation. Our data indicate that higher soil C with grazing was in part the result of more rapid annual shoot turnover, and redistribution of C within the plant-soil system as a result of changes in plant species composition.

Animal Feed↗
PubMed2002

Selenium supplementation and selenium status of dairy cows fed diets based on grass, grass silage or maize silage.

In three separate trial series (TS) the effect of diet composition on selenium (Se) status of dairy cows were investigated. Diets were formulated based mainly on grass (TS1), grass silage (TS2) or maize silage (TS3) with different levels of Se supplementation. Each TS comprised a total of 30 dairy cows and contained one treatment group without Se supplementation (control) and two groups with increasing levels of Se supplementation (levels 1 and 2). Selenium was administered as Na-selenite. The control groups of the different TS showed a very low Se supply of 38-54 microg Se/kg DM. At level 1 the Se supply was increased to 102-165 microg Se/kg DM and at level 2 was 294-373 microg Se/kg DM. After completion of the 6-week trials the average plasma Se concentration of the control cows (without Se supplementation) across all TS was 21.5 microg/l; this increased significantly following Se supplementation, to 37.7 microg/l at level 1 and 61.5 microg/l at level 2. The plasma glutathione peroxidase (GSH-Px) activity of the control cows averaged 67 U/l, rising considerably after supplementation at level 1 to a value of 101 U/l, but showed little further increase at level 2 with a mean value of 120 U/l. By contrast, the average Se content of the milk was unchanged in the control and level 1 groups at 10.5 microg/kg and 10.9 microg/kg, respectively, and only increased markedly after supplementation at level 2 to a mean value of 15.1 microg/kg. The diet based on maize silage, while having a similar Se content as the grass and grass silage-based diets, resulted in a slightly improved Se status, which is due to a higher Se intake from soybean meal.

Animal Feed↗
PubMed1980

The nutritive value of silages. Digestion of nitrogenous constituents in sheep receiving diets of grass silage and grass silage and barley.

1. Two experiments were conducted to study the digestion of nitrogenous constituents in the rumen, small intestine and caecum and colon of sheep given diets of grass silage or grass silage and barley. Three silages were used. One was made from first-harvest grass in the spring and the other from regrowth grass cut in either early autumn or late autumn. All were of perennial ryegrass (Lolium perenne) and were preserved with formic acid. 2. Expt 1 involved a comparison between the spring silage given alone (644 g dry matter (DM)/d) and the spring silage supplemented with barley (151 g DM/d). The intakes (g/d) of total nitrogen for the silage diet and for the supplemented diet were 14.89 and 17.36. Corresponding values (g/d) for N passage were 15.55 and 18.53 (P < 0.01) and the duodenum, 6.01 and 7.09 at the ileum and 5.06 and 5.52 in the faeces. The barley supplement had no significant (P < 0.05) effect on rumen ammonia-N concentration. 3. Expt 2 involved a comparison between the two autumn-cut silages each offered at a level of feeding of approximately 700 g DM/d. The intakes (g/d) of total N for the early-cut silage and for the late-cut silage were 21.67 and 15.62 respectively. Corresponding values (g/d) for N passage were 17.10 and 16.96 at the duodenum, 6.65 and 6.80 at the ileum and 4.5 and 5.22 in the faeces. The concentration of NH3-N in the rumen was significantly (P < 0.001) higher with the early-cut silage than with the late-cut silage. 4. In both experiments the rates of bacterial crude protein (N x 6.25) synthesis in the rumen, estimated using alpha, epsilon-diaminopimelic acid as a marker, were low, 142 and 161 g crude protein/kg organic matter apparently digested in the rumen for the spring silage and the spring silage and barley diets respectively, and 68 and 103 g crude protein/kg organic matter apparently digested in the rumen for the early-cut autumn silage and the late-cut autumn silage respectively. For all diets there was a relatively low contribution of bacterial crude protein to the duodenal passage of crude protein and the amounts of individual amino acids ingested in the diets had a marked influence on the amino acids passing to the duodenum and as a consequence on the mixture of amino acids taken up from the small intestine. 5. The results are discussed in relation to the nutritive value of silage N for ruminants.

Amino Acids↗
PubMed2006

Fat and protein metabolism in growing steers fed either grass silage or dried grass.

Cattle fed grass silage diets have been reported to have high carcass fat:protein ratios. The effect of grass silage and dried grass diets, fed at different levels of intake to ensure a range of equivalent metabolisable energy intakes (MEI) from 1 .1 x metabolisable energy requirement for maintenance to ad libitum, on fat and protein metabolism in twenty-four Hereford x Friesian steers was investigated. After about 84 d of dietary treatment rates of whole-body fat and protein metabolism were measured, as were rates of lipogenesis in omental, perirenal and subcutaneous adipose tissue. Carcass composition was determined. Animals fed silage had greater (P<0 .001) carcass fat:protein ratios than animals fed dried grass at equivalent levels of MEI. Animals fed silage had lower (P<0 .001) rates of protein gain. Rates of leucine entry and oxidation were lower (P<0 .001) in animals fed silage, but there was no dietary difference in the rate of whole-body protein synthesis. There was no dietary difference in the rate of carcass fat gain, but rates of lipogenesis in perirenal adipose tissue were significantly (P=0 .007) higher in animals fed silage. There was no dietary difference in the rate of palmitate and glycerol entry or palmitate oxidation. There were no interactions between MEI and diet, indicating that increments of energy were utilised with the same efficiency from both diets. It was concluded that the high carcass fat:protein ratios of young growing steers was due to limited rates of protein accretion and not to elevated rates of carcass fat accretion.

Acetates↗
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↗
PubMed1995

Grass pollen immunotherapy induces highly cross-reactive IgG antibodies to group V allergen from different grass species.

Sera from two groups of patients receiving grass pollen immunotherapy were tested on IgG reactivity with group V allergen from six different grass species. One group of patients was treated with a mixture of 10 grass species, and the other with a mixture of five. Only Lolium perenne, Dactylis glomerata, and Phleum pratense were present in both mixtures. Although Anthoxanthum odoratum and Secale cereale were absent from the mixture of five, IgG responses to Ant o V and Sec c V were comparable in both patient groups. This reactivity was inhibited for 92-99% with L. perenne extract, illustrating the cross-reactive nature of the IgG antibodies. The presence of A. odoratum and S. cereale in the mixture resulted in only minor amounts of species-specific anti-group V IgG. These results indicate that application of just one grass species in immunotherapy might be sufficient to induce an IgG response that covers other relevant Gramineae species as well.

Allergens↗
PubMed1997

Investigation of different recombinant isoforms of grass group-V allergens (timothy grass pollen) isolated by low-stringency cDNA hybridization--antibody binding capacity and allergenic activity.

A cDNA library of timothy grass pollen was screened for homologous isoforms of major group-V allergens by low stringency hybridization with a Phl p 5 (Phleum pratense) probe. After restriction analysis of the 40 clones obtained, 17 were selected for cDNA sequencing. Of these clones, two were unrelated to group-V allergens, six showed high similarity but an incomplete open reading frame and nine had high similarity with a complete open reading frame. Comparison of deduced amino acids of ten complete cDNA clones confirmed the presence of two major isoforms, a and b. Within these two subgroups, only minor sequence variations were observed. Eight isoforms were expressed in Escherichia coli K12 and purified to homogeneity. Although the subgroups a and b could be distinguished by their molecular masses and by binding constants towards monoclonal antibodies, all isoforms turned out to be biochemically similar. Ribonuclease activity as a marker for the biological function of group-V allergens was shown to be in the same range for both subgroups. Analysis of allergenic B-cell responses towards the isoforms in 26 grass pollen allergic patients revealed that the IgE reactivities to the different isoforms were identical for each individual. IgE reactivities and allergenic activities of three isovariants and an allergen of a different group were compared in a selected group of four grass pollen allergic patients by immunoblot, histamine-release and skin-prick tests. The IgE reactivity does not necessarily mirror the allergenic activity of the single molecule, and the variability of allergenic activity between the isovariants does not, in every case, depend on the structural differences of these allergens. We conclude that group-V isoallergens in grass pollen, although they can be structurally different, induce a similar B-cell response but can show variable allergenic activity. Thus, the most allergenic isoform of each important group of allergens should be sufficient for the diagnosis of type-I allergy. Whether the isoallergenic variation has any significant influence on the outcome of immunotherapy in allergic disease still has to be elucidated.

Allergens↗
PubMed1987

Distribution of a major allergen of rye grass (Lolium perenne) pollen between other grass species.

Polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS) followed by protein staining has shown that extracts from 11 different grass pollens contained proteins with similar molecular weights to that of the allergen R7 from rye grass (Lolium perenne) pollen extract (i.e. 29,000-31,000 daltons). Western blotting and detection with polyclonal (rabbit) antibodies raised against the purified R7 (Rye I) allergen indicated that these proteins were antigenically related and their allergenic properties were demonstrated by the binding of human IgE to immunoblots. The distribution of cross-reacting antigenic determinants was further investigated by immunoblotting with 2 mouse monoclonal antibodies, R7M1 and R7M2, produced with purified R7 as the initial immunogen. The 2 monoclonal antibodies were shown to react with 'R7-like' components of grass pollen extracts other than the component from rye grass. Differences in the distribution of R7M1 and R7M2 binding were found indicating that they are directed at separate R7 epitopes.

Allergens↗
PubMed1980

Analysis of commercial pollen extracts by enzyme determination. I. Comparison of rast-inhibition assay and enzyme titration for orchard grass, rye grass and short ragweed pollen extracts.

Allergenic potency assessed by the 50% RAST-inhibition endpoint titration was compared with enzyme titration for the analysis of commercial pollen extracts. Six different extracts of short ragweed, orchard grass and perennial rye grass were examined. A good correlation (p < 0.01) was found between the acid phosphatase titers and allergenic potency of short ragweed and perennial rye grass extracts. A similar correlation (p < 0.01) was observed between leucin amino peptidase titers and allergenic potency of short ragweed extracts. No correlation could be found with orchard grass extracts. These findings suggest that enzymatic activity may provide a method for the control of certain commercial pollen extracts.

Acid Phosphatase↗
PubMed1989

Comparison of in-house allergen extracts of Phleum pratense (timothy grass) pollen with the international standard and investigation of IgE specificities of a grass-pollen serum pool from West Germany and of the one recommended by the World Health Organization.

We compared our in-house reference extract (RE) and a production extract (PE) with the international reference preparation (IRP) of International Union of Immunological Societies of timothy-grass pollen, using various biochemical and immunochemical methods. Furthermore, we compared the IgE composition of our in-house grass-pollen serum pool (West Germany) with the serum pool recommended by the World Health Organization, using the RE for crossed radioimmunoelectrophoresis (CRIE). Our extracts (RE and PE) were nearly comparable with the IRP. Only by CRIE one more allergen could be detected in RE and PE than in IRP and in another extract purchased from an American company. This finding may depend on the region where the source materials were harvested and which source materials were used for the preparation of the extracts. Furthermore, by high-performance liquid chromatography in the low-molecular-weight range, two distinct peaks could be detected in the nondiafiltered IRP, which were detected in the diafiltered RE and PE as traces only. The IgE composition of our in-house grass-pollen serum pool was comparable with the serum pool recommended by the World Health Organization, as detected by CRIE using RE.

Allergens↗
PubMed1997

Short-term immunotherapy: a prospective, randomized, double-blind, placebo-controlled multicenter study of molecular standardized grass and rye allergens in patients with grass pollen-induced allergic rhinitis.

BACKGROUND: Short-term immunotherapy (STI) can be beneficial for patients who are noncompliant with long-term specific immunotherapy. OBJECTIVE: The efficacy and tolerance of STI with seven preseasonal injections of molecular standardized allergens from grass and rye pollen has been investigated in a double-blind, placebo-controlled multicenter study with 87 patients at 12 German University hospitals. METHODS: Symptoms of the eyes, nose, and bronchi and use of symptomatic drugs were documented daily in diaries by patients with allergic rhinitis to grass and/or rye pollen and without bronchial asthma. Patients were monitored by skin prick test titration and measurement of levels of specific IgE and IgG4. RESULTS: The median nasal score for the 10 weeks with the strongest symptoms during the grass pollen season was significantly lower (p = 0.014) with 35.0 for STI (n = 41) versus 69.0 for placebo (n = 40); the overall symptom score was 54.0 for STI versus 97.5 for placebo (p = 0.020). Only STI-treated patients exposed to less than 40 pollen grains per cubic meter per week showed a significantly lower nasal symptom score of 39.0 versus 75.0 for placebo (p = 0.006); these patients also had fewer nasal symptoms and less use of topical nasal drugs (p < 0.001). The threshold dose in skin prick tests was significantly higher, being 9.06 histamine equivalent for skin prick test (HEP) for STI-treated patients who received the maximum dose (n = 22) versus 4.33 HEP for placebo (p = 0.005). Specific IgE levels were significantly higher, being 55.9 SU/ml for STI versus 39.2 SU/ml for placebo after seven injections (p = 0.006) and level of specific IgG4 was 5.36% for STI versus 1.28% for placebo (p < 0.001). No severe systemic reactions were observed. CONCLUSION: STI with seven preseasonal injections with molecular standardized allergens is effective and well tolerated.

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↗
PubMed1980

The nutritive value of silages. Digestion of organic matter, gross energy and carbohydrate constituents in the rumen and intestines of sheep receiving diets of grass silage or grass silage and barley.

1. Two experiments were conducted to study the digestion of organic matter, gross energy and carbohydrate constituents in the rumen, small intestine and caecum and colon of sheep given grass silage diets. Three silages made from perennial ryegrass (Lolium perenne) with formic acid as an additive were used. One was made from first-harvest grass in the spring and the others from regrowth grass cut from a single sward in either early autumn or late autumn. Expt 1 involved a comparison between the spring silage given alone or supplemented with barley (silage:barley, 4:1 dry matter (DM) basis). Expt 2 involved a comparison between the early-cut and late-cut autumn silages. 2. In Expt 1, supplementation of the silage with barley resulted in a non-significant (P > 0.05) reduction in the proportion of digestible energy (DE) and digestible organic matter digested in the rumen and an increase in the proportions digested in the small intestine. There were also pronounced effects of barley on ruminal cellulolysis and the proportion of digestible cellulose broken down in the rumen was reduced (P < 0.05) from 0.90 to 0.77. There was an increased passage of alpha-linked glucose polymers to the duodenum but even with the supplemented diet 0.91 of the dietary polymers were digested in the rumen. The molar proportion of propionic acid in the rumen tended to be reduced and there were increases in the proportions of butyric acid (P < 0.01) and acetic acid. 3. Expt 2, the digestibility of organic matter, gross energy and cellulose in the early-cut silage was higher (P < 0.01) than in the late-cut silage but there were no significant (P < 0.05) differences between silages in sites of digestion of these constituents. However, the molar proportion of acetic acid in the rumen was higher (P < 0.01) and the molar proportion of propionic acid was lower (P < 0.01) with the late-cut silage than the early-cut silage. 4. The results are discussed in relation to the voluntary intake and utilization of high-digestibility silages.

Animal Feed↗
PubMed1996

The phytochrome gene family in grasses (Poaceae): a phylogeny and evidence that grasses have a subset of the loci found in dicot angiosperms.

The phytochrome nuclear gene family encodes photoreceptor proteins that mediate developmental responses to red and far red light throughout the life of the plant. From studies of the dicot flowering plant Arabidopsis, the family has been modeled as comprising five loci, PHYA-PHYE. However, it has been shown recently that the Arabidopsis model may not completely represent some flowering plant groups because additional PHY loci related to PHYA and PHYB of Arabidopsis apparently have evolved independently several times in dicots, and monocot flowering plants may lack orthologs of PHYD and PHYE of Arabidopsis. Nonetheless, the phytochrome nucleotide data were informative in a study of organismal evolution because the loci occur as single copy sequences and appear to be evolving independently. We have continued our investigation of the phytochrome gene family in flowering plants by sampling extensively in the grass family. The phytochrome nuclear DNA data were cladistically analyzed to address the following questions: (1) Are the data consistent with a pattern of differential distribution of phytochrome genes among monocots and higher dicots, with homologs of PHYA, B, C, D, and E present in higher dicots, but of just PHYA, B, and C in monocots, and (2) what phylogenetic pattern within Poaceae do they reveal? Results of these analyses, and of Southern blot experiments, are consistent with the observation that the phytochrome gene family in grasses comprises the same subset of loci detected in other monocots. Furthermore, for studies of organismal phylogeny in the grass family, the data are shown to provide significant support for relationships that are just weakly resolved by other data sets.

Blotting, Southern↗
PubMed2005

Pituitary adenylate cyclase-activating polypeptide (PACAP) as a growth hormone (GH)-releasing factor in grass carp. I. Functional coupling of cyclic adenosine 3',5'-monophosphate and Ca2+/calmodulin-dependent signaling pathways in PACAP-induced GH secretion and GH gene expression in grass carp pituitary cells.

Pituitary adenylate cyclase-activating polypeptide (PACAP), a member of the glucagon/secretin peptide family, has been recently proposed to be the ancestral GH-releasing factor. Using grass carp as a model for bony fish, we examined the mechanisms for PACAP regulation of GH synthesis and secretion at the pituitary level. Nerve fibers with PACAP immunoreactivity were identified in the grass carp pituitary overlapping with the distribution of somatotrophs. At the somatotroph level, PACAP was shown to induce cAMP synthesis and Ca(2+) entry through voltage-sensitive Ca(2+) channels (VSCC). In carp pituitary cells, PACAP but not vasoactive intestinal polypeptide increased GH release, GH content, total GH production, and steady-state GH mRNA levels. PACAP also enhanced GH mRNA stability, GH promoter activity, and nuclear expression of GH primary transcripts. Increasing cAMP levels, induction of Ca(2+) entry, and activation of VSCC were all effective in elevating GH secretion and GH mRNA levels. PACAP-induced GH secretion and GH mRNA expression, however, were abolished by inhibiting adenylate cyclase and protein kinase A, removing extracellular Ca(2+) or VSCC blockade, or inactivating calmodulin (CaM)-dependent protein kinase II (CaM kinase II). Similar sensitivity to VSCC and CaM kinase II blockade was also observed by activating cAMP production as a trigger for GH release and GH gene expression. These results suggest that PACAP stimulates GH synthesis and secretion in grass carp pituitary cells through PAC(1) receptors. These stimulatory actions probably are mediated by the adenylate cyclase/cAMP/protein kinase A pathway coupled to Ca(2+) entry via VSCC and subsequent activation of CaM/CaM kinase II cascades.

Animals↗
PubMedDate not supplied

Nitrogen availability from composts for humid region perennial grass and legume-grass forage production.

Perennial forages may be ideally suited for fertilization with slow N release amendments such as composts, but difficulties in predicting N supply from composts have limited their routine use in forage production. A field study was conducted to compare the yield and protein content of a binary legume-grass forage mixture and a grass monocrop cut twice annually, when fertilized with diverse composts. In all three years from 1998-2000, timothy (Phleum pratense L.)-red clover (Trifolium pratense L.) and timothy swards were fertilized with ammonium nitrate (AN) at up to 150 and 300 kg N ha(-1) yr(-1), respectively. Organic amendments, applied at up to 600 kg N ha(-1) yr(-1) in the first two years only, included composts derived from crop residue (CSC), dairy manure (DMC), or sewage sludge (SSLC), plus liquid dairy manure (DM). Treatments DM at 150 kg N ha(-1) yr(-1) and CSC at 600 kg N ha(-1) yr(-1) produced cumulative timothy yields matching those obtained for inorganic fertilizer. Apparent nitrogen recovery (ANR) ranged from 0.65% (SSLC) to 15.1% (DMC) for composts, compared with 29.4% (DM) and 36.5% (AN). The legume component (approximately 30%) of the binary mixture acted as an effective "N buffer" maintaining forage yield and protein content consistently higher, and within a narrower range, across all treatments. Integrating compost utilization into livestock systems that use legume-grass mixtures may reduce the risk of large excesses or deficits of N, moderate against potential losses in crop yield and quality, and by accommodating lower application rates of composts, reduce soil P and K accumulation.

Animal Feed↗
PubMed1994

Juice-extracted grass pellets and sodium bicarbonate for cows in midlactation fed timothy grass silage.

Eighteen midlactation Holstein cows, averaging 80 to 125 d of lactation, were used in a trial of switchback design to evaluate two timothy silages, wilted or direct-cut and treated with formic acid, and three treatments, control, NaHCO3 added at 2% of DM, or juice-extracted grass pellets replacing 30% silage DM. Cows fed direct-cut silage that had been treated with formic acid consumed more DM (19.8 vs. 18.6 kg/d) than those fed wilted silage. The DMI was also increased with NaHCO3 and grass pellet treatments. However, NaHCO3 reduced digestibility of most nutrients without affecting pH of rumen fluid or degradation of DM and NDF. Compared with wilted silage, direct-cut silage that had been treated with formic acid contained more degradable NDF (86 vs. 84.5%). Milk yield (24.9 vs. 23.6 kg/d) was higher for cows fed direct-cut than wilted silage, but 4% FCM yield remained unchanged. Addition of NaHCO3 tended to increase yields of milk and 4% FCM. Treatments did not affect milk composition. Serum urea N was higher for cows fed the direct-cut silage than for cows fed wilted silage. Silage type had more impact on feed intake and performance than did NaHCO3 or juice-extracted grass pellets.

Animals↗