bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between vegetation state and bite dimensions of sheep grazing contrasting plant species and its implications for intake rate and diet selection
Authors: EDWARDS G. R. , PARSONS A. J. , PENNING P. D. , NEWMAN J. A. 
Published: April 2006

AbstractThis study used both experimental evidence and a mathematical model to address some differences in interpretation in the literature on the relationship between sward height and the bite dimensions (bite depth, bite area and bite mass) of sheep grazing contrasting vegetation types. Individual non‐fasted sheep were released onto small areas (10 × 10m) of white clover (Trifolium repens) and perennial ryegrass (Lolium perenne) and bite dimensions were measured as they grazed across patches (0·7 × 0·7 m) of predetermined sward surface height (SSH). Sward heights were 4, 7, 10, 13 and 16cm for white clover patches and 4, 6, 5, 9, 11·5 and 14cm for ryegrass patches. Four sheep were assigned to each plant species and each sheep grazed one patch of each height (five patches/sheep). Bite depth, bite area and bite mass increased linearly with SSH in both white clover and ryegrass. At a given SSH, bite depth was similar in white clover and ryegrass, but bite area and bite mass were greater in white clover than in ryegrass. The linear relationships observed between bite mass and SSH contrasted with the asymptotic relationships observed in some other studies, but it is suggested that different relationships may arise because of methodological differences between studies. Furthermore, when linear relationships for bite mass were compared with asymptotic relationships for bite mass in a mechanistic model of animals grazing from ryegrass‐white clover pastures it was demonstrated that the nature of the relationship had relatively little effect on the relationship between intake rate and SSH. This was because intake rate depended on the fundamental mechanistic relationship between bite mass and prehension bite rate. This relationship meant that the greater bite masses found when linear relationship were assumed were associated with reduced prehension bite rates and thus the effect on intake rate was relatively small. In addition, the predictions of the model regarding the bases of diet selection by animals grazing ryegrass‐white clover mixtures were simplified, and stabilized, when linear relationships were assumed.
The effect of sward height and its direction of change on the herbage intake, diet selection and performance of weaned lambs grazing ryegrass swards
Authors: ARMSTRONG R. H. , ROBERTSON E. , HUNTER E. A. 
Published: April 2006

AbstractAbstract Four sward height treatments were imposed by continuous variable stocking using at least ten Suffolk × Greyface lambs per plot from late July to late August: constant 3·5 cm. constant 6·0 cm. 3·5cm increasing to 6·0 cm and 6·0 cm decreasing to 3·5 cm. The treatments were established on two swards given fertilizer N applications over the season of 97 and 160 kg N ha−1 respectively.Animal density was greater on the high fertilizer treatment, at the lower sward height and especially on the decreasing height treatments. Liveweight change of lambs was higher (P <0·001) on the 6‐cm than on the 3·5‐cm treatments (+159 vs‐13g d−1 and was also higher (P <0·001) on the increasing than on the decreasing sward height treatments (+92 vs‐26 g d−1). Herbage organic matter intake (OMI), measured on two occasions in the experiment, was greater (P <0·001) on the 6·0 cm than on the 3·5‐cm sward heights whereas values for the increasing sward height treatments were much greater than those for the decreasing sward height treatments. There was little difference in the organic matter digestibility of the diet between treatments. Diets were composed largely of lamina, although there was more pseudostem and dead herbage in the diets of Iambs grazing the decreasing than the increasing sward height treatments at the end of the experiment. Bite mass was closely related to OMI but the treatment and period differences were relatively greater than for OMI. Bite mass was more closely related to the depth of the lamina layer (sward height‐pseudostem height) than it was to sward height. There was evidence that pseudostem acted as a barrier to defoliation on these short swards and also that the proportion of youngest leaf in the diet was positively related to sward height and to increases in sward height.Sward height and especially the direction of change in sward height, together with associated stock density, were potent influences on lamb growth rate. This was a consequence of differences in herbage intake, which was strongly influenced by bite mass.
The effect of sward height on the liveweight gain of farmed yearling red deer (Cervus elaphus) stags
Authors: HAMILTON W. J. , SIBBALD M. A. , FEIST D. 
Published: April 2006

AbstractThe effect of sward height on the liveweight gain of yearling farmed red deer stags grazing permanent upland pastures in the UK in two successive years is described. The swards received nitrogen fertilizer at a rate of 218 kg ha−1. Red deer stag calves, which had been weaned in September and housed over winter on a hay and concentrate diet to gain on average 57 g d−1 in year 1 and 75 gd−1 in year 2, grazed at one of fourmean sward heights of 4, 6, 8 and 10cm from the beginning of June until September. Liveweight gains were recorded over a period of 15 weeks. All animals were slaughtered and carcass weights were recorded after the end of the grazing period. Liveweight gains and final live weights and carcass weights were significantly (P<0·05) lower on the 4‐cm sward than on the other swards, but there were no differences between the performance of animals on the 6‐, 8‐ and 10‐cm swards.
The manipulation of grass swards for summer‐calving dairy cows
Authors: FISHER G. E. J. , ROBERTS D. J. , DOWDESWELL A. M. 
Published: April 2006

AbstractTwo experiments examined the effects of different defoliation treatments in spring on sward morphology and animal performance in mid‐season and late season. Three treatments were applied in both experiments: Control (C), sward grazed by cows in spring to 6–8 cm grass height. Grazed Aftermath (GA). sward grazed by cows in spring to 3–4cm and allowed to regrow before being grazed by summer‐calving cows, Silage Aftermath (SA), sward not grazed in spring, but a primary cut taken and the sward allowed to regrow before being grazed by summer‐calving cows. The aim of treatment GA was to produce a sward with a high tiller density and high intake characteristics to meet the forage intake requirements of continuously grazed summer‐calving cows, without resorting to offering forage buffers. Experiment 1 was conducted in 1989 on a sandy loam soil and Experiment 2 in 1990 on a heavy loam soil.In both experiments the GA treatment led to high live tiller density and live: dead tiller ratios compared with the C and SA treatments. Differences in sward morphology were also detected by applying double normal distribution analyses to measurements of grass height. The GA treatment also increased sward herbage mass and, to a limited extent, herbage metabolizable energy and crude protein contents. The results from Experiment 1 suggested that these sward effects lead to increased herbage dry‐matter intake (as estimated by the n‐alkane technique) and milk yield in cows grazing the GA sward. However, in Experiment 2, where conditions for grass growth in mid‐season were more favourable than in Experiment 1, the differences in sward morphology produced in spring were quickly lost in June and July. There were therefore no differences in herbage intake or milk yield in the second experiment. Herbage intakes (kgDMd−1± s.e.d) estimated in July for cows on treatments C, GA and SA were 11·0, 13·4, 10·1 ± 2·16 for Experiment 1 and 10·7, 11·1, 11·2 ± 2·32 for Experiment 2. Average milk yield (kgd−1± s.e.d.) for cows on treatments C, GA and SA were 26·1, 28·0, 25·6 ± 0·31 (Experiment 1) and 28·5, 27·3, 28·4 + 0·58 (Experiment 2).The results suggested that acceptable milk yields can be obtained from grazing summer‐calving cows, without offering forage buffers, by applying high stocking rates (low grass heights) in spring. However, the benefits of this manipulation could be lost by lax grazing in mid‐season.
The use of roll‐conditioning and potassium carbonate (K2CO3) to increase the drying rate of lucerne (Medicago sativa L.)
Authors: MEREDITH R. H. , WARBOYS I. B. 
Published: April 2006

AbstractMechanical and chemical treatments to accelerate the drying of cut lucerne were evaluated under laboratory conditions. Plant material was treated with a 016 M solution of potassium carbonate (K2CO3) and/or lightly pressed between a pair of smooth rollers (roll‐conditioning).Drying times to 33% moisture content (MC), expressed on a dry weight basis (dwb), were reduced by 49% by roll‐conditioning, 76% by K2CO3) treatment and 77% by the combined K2CO3+ roll‐conditioning treatment. The main benefit from combining the two forms of treatment was an improved uniformity of drying; when whole shoots were at 61% MC (dwb) the difference between leaf and stem moisture contents was reduced by 28% (roll‐conditioning), 38% (K2CO3) and 54% (K2CO3+ roll‐conditioning) relative to the untreated control.
Quality of grass silage infected with spores of Clostridium tyrobutyricum
Authors: RAMMER CHRI 
Published: April 2006

AbstractThe influence of adding clostridial spores to silage was studied in 2 successive years. Direct‐cut, precision‐chopped herbages were infected with spores of Clostridium tyrobutyricum in doses varying from 0 to 106 g−l fresh material (FM), and ensiled in experimental silos. The material was treated with or without 4 ml formic acid (85%) kg−1 FM. Silo contents were studied after 4.20 (or 50) and 100 days of ensiling.Contents of dry matter, water‐soluble carbohydrate, nitrate as well as buffering capacity of FM varied between the 2 years at harvest, whereas the numbers of clostridial spores were about the same (< 102 g−1).Infecting the crop with clostridial spores negatively affected the quality of silage in the first year. After 50 days spore numbers in the silages had increased by 40 × 103 to 150 × 103 times in the infected silage, compared with 5 × 103 in the uninfected silage. No effect was seen in the second year.Silage with high spore counts showed no residual nitrate content. Formic acid improved silage quality from a chemical point of view but had no anti‐clostridial effect. Ensilability of a crop seems to be more important than the initial count of Clostridia for a successful ensiling process.
Effect of forage removal at the first detectable node stage on the growth of winter and spring triticale
Authors: ROYO C. , ROMAGOSA I. 
Published: April 2006

AbstractThe effect of forage removal on the growth of five winter and five spring triticale genotypes was studied in 1992 and 1993 in field experiments in north‐eastern Spain. When cut, winter triticales produced more biomass and leaf area than spring types owing to their higher tillering capacity. The leaf area index (LAI) at anthesis was similar in both groups in both clipped and uncut plots, but spring triticales had a greater leaf area on the main stem than winter types. Winter types had a greater leaf area on the tillers than spring types. Spring and winter types had a similar physiological response to forage removal, except for modifications in flag leaf area. In spring types triticale flag leaf area was reduced by clipping, whereas in winter types flag leaf area was increased. Forage removal resulted in less dry‐matter accumulation in all plant parts, maximum weight of the plant being reduced by about 20% and the rate of growth by around 13%. LAI at anthesis decreased by 37% as a result of clipping, and the leaf area duration from anthesis to maturity decreased by 36%. The duration of growth increased after clipping. Heading, anthesis and maturity dates were delayed by clipping, but grain filling duration was not affected.
Grass silage as a basic feed for store lambs. 1. Effect of wilting, chop length and stage of maturity of grass silage on intake and performance of store lambs
Authors: FITZGERALD J. J. 
Published: April 2006

AbstractTwo experiments were carried out with grass silages cut at a leafy (Experiment 1) and a more mature (Experiment 2) stage of growth to evaluate the effect of wilting and chop length on silage intake and performance of store lambs. In each experiment, the herbage was cut with a rotary mower and was either ensiled within 24 h as unwilled silage (U) or wilted for 1–3 d (W). Each silage type was harvested with either a double‐chop harvester (D) or a precision‐chop harvester (P). All silages were treated with formic acid at 3 1 t−1 and were well preserved. The silages were fed ad libitum to Suffolk crossbred store lambs (twenty‐four lambs per treatment) without any supplement over a period of 8 or 9 weeks.Wilting of the silages had little effect on silage intake (797 vs. 809g dry matter (DM) d−1) or on lamb performance in Experiment 1. In Experiment 2, wilting of the D silage increased silage DM intake (589 vs. 534 g DM d−1; +10%) and reduced the extent of liveweight losses. Wilting of the P silage reduced silage intake (770 vs. 791g DM d−1; ‐3%) and reduced liveweight gains.In Experiment 1 intakes of the D silages were 650–667g DM d−1 and just maintained lamb live weights. Intakes of the P silages were 39–49% higher than the D silages (927–968 g DM d−1) and increased liveweight gains. In Experiment 2 intakes of the D silages were 534–589 g DM d−1 and resulted in a loss in lamb live weight. Precision‐chopping increased silage intakes by 31–48% (770–791 DM d−1)in Experiment 2 and improved lamb liveweight gains. Lamb performance was higher on the UP silage than on the WP silage.The rumen retention lime (RRT), estimated from the rumen contents of the lambs at slaughter and their silage intake before slaughter, was much shorter for the lambs fed on the P silages (12.6–20.6 h) than those fed on the D silages (21.4–29.3 h) in each experiment.Silage intake and liveweight gain were positively related to silage in vivo DM digestibility (DMD), whereas RRT was negatively related to DMD. However, there were distinct differences between the P and D silages in the elevation and, to a lesser extent, in the slope of the regression lines, indicating that intake of D silage was limited by factors other than the digestibility of the silageThe results of this study show that the chop length of grass silage had a far greater effect on intake and on lamb performance than silage digestibility, whereas wilting had little or no effect.
Grass silage as a basic feed for store lambs. 2. Effect of harvesting system and chop length of grass silage on silage intake and performance of store lambs
Authors: FITZGERALD J. J. 
Published: April 2006

AbstractA perennial ryegrass sward was cut at a leafy stage of growth and harvested with different harvesters to produce silages differing in chop length to evaluate the effect of silage chop length on silage intake and on the performance of store Iambs when silage was fed as the sole diet. The silage was harvested in late May either as long silage (L), single‐chopped (S). double‐chopped (D). long precision‐chopped (LP) or medium precision‐chopped (MP) silage with (he appropriate machinery. The silages were treated with formic acid at 2.5 1 t−1. were well preserved (pH 3.7–3.8) and were of high dry‐matter digestibility [749–810 g DMD kg−1 dry‐matter (DM)]. The silages were fed ad libitum as the sole diet to Suffolk crossbred store lambs over a period of 11 weeks.Silage intake and lamb performance progressively increased as silage chop length declined from 32.4 cm (L) to 6.8 cm (MP). Silage intakes were 572, 661, 750, 893 and 1129 (± 21) g DM d−1 for silages L, S, D, LP and MP respectively. The corresponding daily liveweight gains were ‐3, 40, 53, 85 and 151 (± 7.6) g d−l. Similar increases in empty body weight gain and carcass weight gain were obtained as silage chop length declined.Rumen retention time (RRT), estimated from the rumen contents of the lambs at slaughter and their silage intake in the week before slaughter, was much shorter for silages LP and MP compared with silages L or S. Silage intake was negatively related to RRT(b= ‐24.5 ± 6.1 gDM h−l RRT).The results of this study showed that high intakes of grass silage and liveweight gains were achieved when grass was cut at a leafy stage of growth and harvested with a precision‐chop harvester set to produce a moderate chop length (7 cm). The feeding of long or flail‐chopped silages resulted in lower intakes and lower liveweight gains.
Mechanical removal of surface moisture from grass
Authors: KNIGHT A. C. , PRICE J. S. , GALE G. E. 
Published: April 2006

AbstractA laboratory‐scale study was conducted to evaluate various methods of removing surface moisture from grass during forage harvesting. This moisture originates from dew or rain deposits, and contributes directly to the production of silage effluent. Measurements were made to determine the quantity of surface moisture on unharvested grass and the removal efficiency that centrifuging, shaking, squeezing and blowing treatments might be expected to achieve. The absolute quantity of surface moisture on the samples, which included four varieties, was estimated by blotting. The results indicated that tall fescue retained 53% more surface moisture when left in swaths during prolonged wet weather compared with unmown crop. When the wet standing crop was mown, the brush mower conditioner removed 57% of its surface moisture.Centrifuging and blowing to achieve aerodynamic dispersion of surface moisture were found to be more effective than shaking and squeezing, but estimations of the likely complexity, size and cost of field equipment showed them to be unrealistic options at the farm scale. Italian ryegrass was found to release surface moisture slightly more readily than perennial ryegrass, tall fescue or Yorkshire fog.
Efficiencies of ryegrass and white clover herbage utilization in mixtures continuously grazed by sheep
Authors: LOUAULT F. , CARRÈRE P. , SOUSSANA J. F. 
Published: April 2006

AbstractA method for measuring the growth, senescence and defoliation fluxes in a mixture consisting of alternate rows of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) was used to calculate the actual and potential efficiencies of grass and clover utilization under continuous sheep grazing. White clover contributed relatively more to the growth than to the herbage mass of the mixture and its relative growth rate was usually significantly greater than that of its companion grass. The primary reason for the greater potential efficiency of herbage use of the white clover component was, however, its lower rate of senescence. Greater potential efficiency was not reflected in a greater actual efficiency because the contribution of white clover to the total herbage removed was always smaller than its contribution to the growth flux of the mixture. Despite the commonly assumed sheep preference for white clover, the legume was usually the least defoliated species, presumably because of the lower surface height of white clover compared with grass, which resulted in a lower vertical availability of white clover, thereby restricting its defoliation rate. The positive net herbage accumulation observed with white clover at a constant sward surface height occurred partly through stolon and bud development and partly through the growth of undefoliated leaves from axillary growing points and contributed to a net herbage accumulation per unit dry weight in white clover greater than that in ryegrass. This resulted in an increase in the white clover content of the sward, which was observed independently by destructive measurements.
Innate immune responses regulate trypanosome parasite infection of the tsetse fly Glossina morsitans morsitans
Authors: Hu Changyun , Aksoy Serap 
Published: April 2006

SummaryTsetse flies transmit the protozoan parasite African trypanosomes, the agents of human sleeping sickness in sub‐Saharan Africa. Parasite transmission in the insect is restricted by a natural resistance phenomenon (refractoriness). Understanding the mechanism of parasite resistance is important as strengthening fly’s response(s) via transgenic approaches can prevent parasite transmission and lead to the development of novel vector control strategies. Here, we investigated the role of one of the two major pathways regulating innate immunity in invertebrates, the immunodeficiency (Imd) pathway, for Glossina morsitans morsitans’s natural defence against Trypanosoma brucei spp. infections. We determined the molecular structure of the Imd pathway transcriptional activator Relish (GmmRel), which shows high amino acid identity and structural similarity to its Drosophila homologue. Through a double‐stranded RNA‐based interference approach, we showed that the pathogen‐induced expression profile of the antimicrobial peptides (AMPs) attacin and cecropin is under the regulation of GmmRel. Unexpectedly, the AMP diptericin appears to be constitutively expressed in tsetse independent of the presence of the Rel factor. Through GmmRel knock‐down, we could successfully block the induction of attacin and cecropin expression in the immune responsive tissues fat body and proventriculus (cardia) following microbial challenge. The midgut and salivary gland trypanosome infection prevalence, as well as the intensity of midgut parasite infections were found to be significantly higher in flies when attacin and relish expression were knocked down. Our results provide the first direct evidence for the involvement of antimicrobial peptides in trypanosome transmission in tsetse.
Case of multiple myeloma associated with extramedullary cutaneous plasmacytoma and pyoderma gangrenosum
Authors: Yoon Yang Hyun , Cho Wan Ik , Seo Seong Jun 
Published: April 2006

AbstractA variety of cutaneous manifestations has been described in multiple myeloma including extramedullary cutaneous plasmacytomas, cutaneous amyloidosis, pyoderma gangrenosum, leukocytoclastic vasculitis, necrobiotic xanthogranuloma, scleromyxedema, Sweet's syndrome, subcorneal pustular dermatosis, scleredema, and plane xanthomas etc. An 89‐year‐old Korean man, who had been suffering from multiple myeloma 1 year previous, presented for evaluation of two nodules on the right side of the forehead, left side of the chest (7th rib area), and multiple ulcers with papulopustules on both the thigh and the left side of the chest (2nd rib area) during 15 days, which developed at the same time. A biopsy of a lesion which manifested as a cutaneous nodule on the right side of the forehead revealed dermal infiltration by well‐differentiated plasma cells, similar to those found on a bone marrow biopsy, and a biopsy of the lesion manifested as a painful ulceration on the right thigh area showing dermal neutrophilic infiltration. Histologic findings were consistent with plasmacytoma and pyoderma gangrenosum, respectively. We present a case of multiple myeloma which developed extramedullary cutaneous plasmacytoma and pyoderma gangrenosum simultaneously, which is very rare.1 The patient was treated with a systemic steroid and conservative therapy.