bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variability of the in vitro digestibility of standard herbage samples
Authors: DHANOA M. S. , DERIAZ R. E. 
Published: April 2006

AbstractThe results or estimations of in vitro digestibility of three standard herbage samples, analysed weekly over about 48 weeks per year, have been examined using time‐series methods of Box and Jenkins to separate seasonal and non‐seasonal trends. The study includes data from March 1971 to February 1981. The dominant feature of variability is the seasonal component with a cycle of 52 weeks; no other significant cycles of longer periods were detected. The model of Box and Jenkins (1976) was found to be the most appropriate in describing the three series. A decrease in the in vitro digestibility of the low standard, which is 10 years old, occurred over the last year or so, although the reasons for this apparent storage effect are unknown.
Sward composition and output on grassland farms
Authors: PEEL S. , GREEN J. O. 
Published: April 2006

AbstractRecords of grassland productivity were kept for 2 years on 136 lowland dairy farms and 131 lowland beef farms. The grassland on each farm was classified according to the proportion of sown (preferred) species. The farms were then ranked on this basis and divided into quarters:On dairy farms the lowest quarter had 31% sown species and utilized metabolizable energy (UME) output from grass of 40.8 GJ ha−1, whereas the highest quarter had 70% sown species and UME output of 45.6 GJ ha−1. Dairy farmers in the lowest quarter used least fertilizer N and differences in output were no greater than would be expected from differences in N input. On beef farms the lowest quarter had 28% sown species and UME output of 32.3 GJ ha−1, and the highest quarter had 63% sown species and UME output of 45.9 GJ ha−1On these farms differences in fertilizer N could not completely account for differences in output.It is concluded that on beef farms botanical composition of grassland is a good indicator of its productivity but is not necessarily a prime cause of differences in output. On dairy farms there is little evidence of a direct benefit resulting from a high proportion of sown species. On such farms the need for deliberate manipulation of the botanical composition of grassland by reseeding or chemical means is questioned.
The effect of stocking rate and fertilizer usage on income variability for dairy farms in England and Wales
Authors: DOYLE C. J. , LAZENBY A. 
Published: April 2006

AbstractA mathematical model of grass production and utilization on a dairy farm is described. Using the model an assessment has been made of the extent to which financial uncertainty arising from year‐to‐year variability in grass yields, coupled with a preference among farmers for minimizing risks, may explain the relatively low stocking rates and observed nitrogen usages on many dairy farms in England and Wales. The degree of risk has been equated with the probability of profits in a particular year being less than those required to cover the consumption needs and short‐term borrowing requirements of the farmer. The results of the analysis indicate that a strategy of minimizing risks may lead to a significantly lower stocking rate than one of maximizing profits. Thus, considerations of risk may lead to stocking rates which are suboptimal from the viewpoint of economic and biological efficiency. However, there is no evidence to suggest that the comparatively low average usage of nitrogen on dairy farms in the UK is determined by risk considerations. On the contrary, increasing nitrogen usage lowers the apparent financial risk at a given stocking rate.
The drying rates of component parts of inflorescence‐bearing tillers of Italian ryegrass
Authors: HARRIS C. E. , DHANOA M. S. 
Published: April 2006

AbstractInflorescence‐bearing tillers of Italian ryegrass (Lolium multiflorum cv. RvP) were dried in controlled temperature, relative humidity and air speed conditions chosen to be within the range likely to occur in a hay swath drying in the field. After drying for increasing intervals the tillers were separated into inflorescence, exposed flowering stem, leaf‐laminae, leaf‐sheath and flowering stem enclosed by leaf‐sheath and the drying rates of these components in addition to that of whole tillers were measured. There were large differences in drying rate between components, but the differences were similar over the range of drying conditions employed. The drying rate of the inflorescence as well as that of stem enclosed by leaf‐sheath was found to be very low and that of leaf‐laminae and leaf‐sheath very high.
The ingress of Poa annua into perennial ryegrass swards
Authors: WELLS G. J. , HAGGAR R. J. 
Published: April 2006

AbstractThe ingress of Poa annua into established swards of perennial ryegrass was recorded in four experiments aimed at determining whether ingress was due to P. annua aggression or to a decrease in ryegrass vigour. Emphasis was placed on severity of defoliation, effect of bare spaces and the time of year most favourable to colonization.In Experiment 1, P. annua ingress was greatest in the autumn, especially where ryegrass had been sown in rows rather than broadcast sown. In Experiment 2, seedlings of P. annua only established successfully in mature ryegrass swards that had been defoliated at intervals of two weeks. Experiment 3 showed that ingress was inversely related to the vigour of the ryegrass cultivar, being particularly high on frequently defoliated plots. In Experiment 4, which involved a study of the colonization of poached areas, more seedlings established in quadrats surrounded by P. annua‐dominant pasture compared with patches surrounded by perennial ryegrass.It is concluded that P. annua is not an aggressive species; it colonizes only open ryegrass swards that have become weakened by intensive management.
Some effects of fertilizer and frequency of defoliation on the botanical composition and yield of permanent grassland
Authors: WILLIAMS E. D. 
Published: April 2006

AbstractSmall plots of permanent pasture containing 50%Agrostis capillaris‐Festuca rubra were defoliated frequently or infrequently during the growing seasons in 1978–80 and fertilized with 133, 125 and 125 kg N, P2O5 and K2O respectively ha−1 a −1 or not fertilized during 1978–81. Yields of herbage were assessed during 1979–80 and botanical composition assessed on three occasions in 1978, once in April 1979 and once in 1982.Fertilizer application increased annual dry matter (DM) harvested from frequently cut plots by 40%, 53% and 65% in 1978, 1979 and 1980 respectively, and on infrequently cut plots it doubled hay DM harvested in 1978 and increased total DM harvested by 126% and 186% in 1979 and 1980 respectively. Infrequent cutting and fertilizer both decreased the proportion of A. capillaris but only fertilizer decreased the proportion of F. rubra. Fertilizer greatly increased the proportion of Holcus lanatus especially where plots had been cut frequently and of Alopecurus pratensis where they had been cut infrequently. It decreased the proportion of Luzula campestris. Infrequent cutting, especially with fertilizer, discouraged Cerastium fontanum ssp. glabrescens and Trifolium repens but encouraged Rumex acetosa.
A comparison of a rising‐plate meter and an electronic capacitance meter for estimating the yield of pastures grazed by dairy cows
Authors: STOCKDALE C. R. , KELLY K. B. 
Published: April 2006

AbstractThe performances of a rising‐plate meter and a single‐probe electronic capacitance meter were compared for estimating the herbage mass of irrigated pastures both before and after grazing by dairy cows. Mean CV for the rising plate meter and the single‐probe meter were 12.7% and 13.3% respectively when herbage mass was measured before grazing, and 21.8% and 15.4% respectively immediately after grazing. These coefficients of variation indicate that while the performance of the two meters was similar when herbage mass was measured before grazing, the single‐probe meter was a more precise instrument for estimating herbage mass after grazing.Trampling of herbage prior to measurement had a major effect on the regressions of both meters; the regression intercept was increased by 2800 kg dry matter (DM) ha−1 for the rising‐plate meter and by 2580 kg DM ha−1 for the single‐probe meter. The slopes of the graphs, however, remained unchanged.It was concluded that while the single‐probe meter performed better than the rising‐plate meter for estimating the mass of post‐grazing herbage when trampling was negligible, the large effect that trampling had on the post‐grazing calibration regressions precluded both instruments from general use in dairy cattle research. This indicates that another technique is required in circumstances in which pastures are heavily trampled.
Establishment of legumes in grass swards: effects of pesticides on slugs, insects, legume seedling numbers and forage yield and quality*
Authors: BYERS R. A. , TEMPLETON W. C. , MANGAN R. L. , BIERLEIN D. L. , CAMPBELL W. F. , DONLEY H. J. 
Published: April 2006

AbstractThree legumes, red clover (Trifolium pratense L.), alfalfa (Medicago sativa L.) and birdsfoot trefoil (Lotus corniculatus L.), were planted with a minimum‐tillage drill into eight grass fields, three in early spring, two in late spring and three in late summer, in Pennsylvania. The objective was to use pesticides at planting time to control slugs and insects which attack legume seedlings and ascertain whether pest control prevented seedling loss and increased yields of grass and legume dry matter (DM), in vitro DM digestibility and crude protein (CP). Methiocarb bait alone or in combination with carbofuran granules or spray applied at planting sometimes controlled the slugs Derocerus reticulatum (Müller), D. laeve (Müller) and Arion fasciatus Nilsson and improved establishment of seedling red clover and alfalfa but not birdsfoot trefoil. Increased yields of DM, digestible DM, CP and legume DM after treatment was greatest in late‐spring sowings. Larvae of the clover root curculio, Sitona hispidulus (F.), attacked roots of legumes in the spring following the year of sowing. Late spring and summer sowings without pesticides sustained considerable seedling losses from pests, whereas seedlings from early spring sowings in untreated areas were injured less.
Canopy structure and productivity of Festuca avundinacea Schreb. swards during vegetative and reproductive growth
Authors: SUGIYAMA S. , YONEYAMA M. , TAKAHASHI N. , GOTOH K. 
Published: April 2006

AbstractCanopy structure, productivity and their relationships were examined in 2‐year‐old swards of fourteen tall fescue (Festuca arundinacea Schreb.) strains during the vegetative and reproductive growth stages. During the vegetative growth stage morphological characters, particularly tiller size, were closely associated with productivity. Swards with large tillers showed an effective distribution of the incoming light energy within the canopy and hence low extinction coefficient (K) value and high productivity at complete light interception. On the other hand, although there was no apparent correlation between K and the productivity or the whole crop during the reproductive growth stage, the productivities of the reproductive and vegetative tillers were positively and negatively related to K respectively. Leaf area index of the reproductive tillers and their position in the canopy had marked effects on the distribution of the incoming light energy within the canopy and on the productivity of both types of tillers. The productivity of the vegetative and the reproductive tillers is discussed in terms of the effect of the competition for incoming light energy between both types of tillers.
Silage and milk production: studies with molasses and formic acid as additives for grass silage
Authors: CASTLE M. E. , WATSON J. N. 
Published: April 2006

AbstractIn two separate feeding experiments using a total of twenty‐four individually housed Ayrshire cows six silages made from perennial ryegrass were offered ad libitum with supplements of concentrates. In Experiment I herbage with a dry matter (DM) concentration of 225 g kg−1 received either formic acid (‘Add‐F’) at the rate of 2·0 litres t−1 or undiluted cane molasses at rates of 10, 20 and 30 litres t−l; the mean daily silage intakes were 9·54, 908, 9·27 and 9·49 kg DM per cow and the daily milk yields, corrected to 40 g fat kg−1, were 23·2, 22·3, 22·8 and 22·9 kg per cow respectively but none of the differences between the four treatments was significant. In Experiment 2 herbage with a DM concentration of 269 g kg−1 received formic acid at a uniform rate of 2·6 litres t−1 either with or without an additional application of molasses at 20 litres t−1; the mean daily silage DM intakes were 8·70 and 9·28 kg per cow and the daily fat‐corrected milk yields were 22·2 and 21·9 kg per cow respectively and were not significantly different. In both experiments the effects of the treatments on milk composition were small and not significant. It is concluded that there were no advantages in applying molasses to herbage treated with formic acid, and that the rate of application of molasses to untreated herbage which equated with the formic acid application was 20·30 litres t−l when assessed on the basis of silage composition, intake and milk production.
Unwilted and prewilted grass silage for finishing bulls*
Authors: COTTYN B. G. , BOUCQUE V. , FIEMS L. O. , VANACKER J. M. , BUYSSE F.X. 
Published: April 2006

AbstractThree silages were prepared from perennial ryegrass; unwilted without additive (UW), unwilted treated with 3·5 litres commercial (85%) formic acid (UWA) and prewilted without additive (WN) with dry matter (DM) concentrations of 189, 209 and 328 g kg−1 respectively. The three silages were offered ad libitum in a 348‐d feeding experiment to three groups of eight Belgian white‐blue bulls with an initial live weight (LW) of 277 kg. The concentrate (47 g digestible crude protein (CP) kg−1) supplementation was 7·5 g (kg LW)−1. Acid treatment (UWA) slightly improved digestibility of all silage nutrients except CP, whereas wilting generally slightly decreased digestibility of the nutrients except DM and ether extract. The daily LW gain averaged 912 g and was not significantly different on the three different treatments. DM intake per (kg LW)0.75 was higher with the UWA silage, 69·3 g, and with the WN silage, 71·6 g, than with the UW silage, 65·8 g. However, this difference in DM intake was not reflected in either daily LW or carcase gain. The DM of UW silage was more efficiently utilized than DM of UWA or WN silage.
The effects of stocking rate and nitrogen fertilizer on a perennial ryegrass‐white clover sward
Authors: CURLL M. L. , WILKINS R. J. , SNAYDON R. W. , SHANMUGALINGAM V. S. 
Published: April 2006

AbstractThe effects of stocking rate and N fertilizer on a mixed sward of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) set‐stocked with sheep were examined. Sward production and composition, and sheep production were studied.Increasing the stocking rate over the range 25–55 yearling sheep ha−1 reduced herbage accumulation by about 40%, whether or not N fertilizer was applied. Increasing the stocking rate increased the density of ryegrass tillers, but reduced the density of clover stolons and the clover content of the swards. Applications of N fertilizer (200 kg N ha−1 a−1) increased herbage accumulation by about 20% but substantially reduced the clover content.Liveweight gain per animal and per unit area were greater at the lower stocking rates where the clover content and nutritive value of the diet were greatest. Wool growth per unit area was greater at the higher stocking rates. Applications of 1M fertilizer increased liveweight gain at stocking rates above 25 sheep ha−1, but had no effect on wool production at any stocking rate.The results demonstrate that a stable and productive grass‐clover association was maintained under conditions of set‐stocking at around 23 yearling sheep ha−1and that at this stocking rate, which appears to be about the biological optimum, there was no advantage in using N fertilizer.
The effect of nitrogenous fertilizer on the photosynthesis of leaves of a ryegrass sward
Authors: WOLEDGE JANE , PEARSE P. JOY 
Published: April 2006

AbstractThe addition of nitrogenous fertilizer to a newly cut, N‐deficient ryegrass sward resulted in an increased photosynthetic capacity in the next leaf to expand, showing that greater photosynthesis per unit leaf area as well as greater leaf area contributes to the increased growth of fertilized swards. Later in the 4‐week growth period there was little difference in photosynthetic capacity between fertilized and unfertilized swards.
Resistances of grasses to two sobemoviruses, cocksfoot mottle and cynosurus mottle
Authors: CATHERALL P. L. 
Published: April 2006

AbstractInfection of Dactyls glomerata with cocksfoot mottle virus (Cf MV) and of Cynosurus cristatus with cynosurus mottle virus (CyMV) is frequently lethal. However, varieties of each species differ in the proportion of genotypes which survive, and in the damage suffered by these surviving plains. Infected plants of the CfMV‐resistant cocksfoot, cv. Cambria, were generally much more aggressive in the competitive environment of the sward than were infected plants of the susceptible cv. S37. Thus, Cambria populations outyielded comparable populations of S37 by only 7% when healthy, but by 40% when infected with CfMV. A few genotypes in the infected Cambria population apparently recovered from the disease, became virus‐free and were immune to further infection Resistance to CyMV in C. cristatus takes the form of resistance to systemic spread. A few symptomless and apparently virus‐free tillers grow up from the bases of infected tillers. However, these tillers are susceptible to further infection. It is suggested that, in resistant genotypes, CfMV and CyMV trigger the production of antiviral agent(s) which block or restrict virus replication. There is some evidence that CfMV resistance is virus isolate specific, and this could present problems when breeding for durable resistance.
Effect of after‐treatments on sward composition and the establishment of introduced species following the control of bracken
Authors: SPARKE C. J. 
Published: April 2006

AbstractAfter bracken control with asulam the surface litter was removed by raking, burning or incorporation, or left in situ as a control. The proportion of grasses in the sward and the grass net herbage production was not significantly different on the four litter treatments 1 or 2 years after spraying.Lime, phosphate and seed of Trifolium repens, Lolium perenne and Festuca rubra were applied to a similar set of four litter treatments. T. repens failed to establish in quantity on any treatment. A long period of dry weather following sowing may have been the initial reason, with competition from the established, more vigorous grasses subsequently being of importance. The sown grasses established most successfully where competition from the existing indigenous species had been removed by burning or incorporation of the litter and surface vegetation. Although these two treatments differed little in the proportion of sown grasses in the sward in the second season, the net herbage production of Lolium and Festuca was significantly higher on the incorporated than the burnt treatment. Net herbage production of these two grasses in the second season was significantly higher on the incorporated and the burnt treatments than it was on the control. After 2 years, total grass net herbage production was significantly greater on these two treatments than on the unfertilized, unlimed and unseeded control.
Manurial value of septic‐tank sludge on grassland
Authors: CARLTON‐SMITH C. H. , COKER E. G. 
Published: April 2006

AbstractAbout 5% of the UK population is served by septic tanks and cesspits. In some districts this is applied to farmland. The Water Research Centre and South‐West Water collaborated in establishing a field trial to provide knowledge of the manurial value of septic‐tank sludge. The trial was designed to investigate the value of nitrogen (N), phosphorus (P) and potassium (K) contained in the sludge and applied over a 3‐year period to grassland. The approximate proportions of total nutrients present in the sludge applied which became available to ryegrass as inorganic fertilizer nutrients were: Barley grown in the fourth year when no sludge was applied showed a significant response to residual sludge N and P remaining in the soil. It is concluded that septic‐tank sludge can supply useful amounts of N and P, and, unlike other forms of sewage sludge, significant quantities of K to grassland. Estimates of the nutrient value should be based on analysis for dry solids, and total N, P and K. Septic‐tank sludge is usually low in metal content and no metal contamination problems should arise when it is applied to land.
Effects of improved nutrition during lactation on the performance of hill lambs
Authors: O'TOOLE M. A. 
Published: April 2006

AbstractTwo experiments compared the effects of grazing by hill ewes with single lambs on lowland pasture for varying periods of time. In Experiment 1 lambs kept with their mothers on lowland pasture for 0, 21, 42 or 70 d before being moved to hill grazing gave daily liveweight gains (g) of 243,329, 338 and 348 respectively in the 1–21 days postpartum period; 243,248,310 and 314 in the 22–42 days period; 118, 132, 157 and 229 in the 43–70 days period and 105, 100, 115 and 98 in the 71 days to weaning period. In Experiment 2, ewes with single lambs grazed lowland pasture for 0, 21, 56 and 110 days and the daily liveweight gains (g) recorded were 233, 348, 343 and 353 respectively in the 1–21 days postpartum period; 184, 229, 306 and 297 in the 22‐56 days period and 109, 115, 141 and 209 in the 57‐110 days period. At each weighing up to weaning there was a positive correlation between lamb weight and the number of days spent on lowland pasture. Carcass weight and killing out percentages were each also significantly improved. The implications of these results in developing a hill‐sheep system are discussed.
The voluntary intake and in vivo digestibility of herbage harvested from indigenous hill plant communities
Authors: ARMSTRONG R. H. , COMMON T. G. , SMITH HELEN K. 
Published: April 2006

AbstractVoluntary intake and in vivo digestibility of herbage harvested from five indigenous communities–Agrostis‐Festuca, Nardus and Molinia grasslands and Eriophorum vaginatum‐ and Trichophorum caespitosum‐dominated varieties of blanket bog–and also from sown Lolium perenne and Trifolium repens swards were measured over two years. First growths of each sward were harvested at three stages of maturity and stored at — 20°C before feeding. Voluntary intake was measured while feeding ad libitum to 15% excess of the intake on the previous day and digestibility when feeding at 80% of voluntary intake.There was a common positive relationship (r2= 0·86***) between intake (adjusted for year of feeding, range 72·8–16·7 g organic matter (kg LW)0·75 d‐1) and organic matter digestibility (range 0·796–0·371), covering Lolium perenne and most of the indigenous communities. However, there were significant differences between the regressions of intake on the concentration of neutral detergent fibre for ryegrass and the indigenous communities, and also between the regressions for individual communities.The results demonstrated the general value of organic matter digestibility as a predictor of intake potential, and the high digestibility and intake potential of immature vegetation from the grass and grass heath communities.