bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fertilizer and lime‐pellet requirements for seed of white clover used for improving permanent pastures†
Authors: MURPHY W. M. , DUGDALE D. T. , ROSS D. S. 
Published: April 2006

AbstractPermanent pastures on acid soils in the northeastern USA produce far below their potential due to lack of legumes in the swards. This experiment was done to study the effects of lime‐pelleted white clover seed and fertilizer combinations (B, Cu, K, Mg, Mo, P, S and Zn) on clover nodulation and growth in four acid (pH 4.3–4.9), Vermont permanent‐pasture soils in the greenhouse. Potassium was applied in all treatments. Lime pelleting and Mg and P fertilization increased both proportion of plants nodulated and seedling weight. Lime pelleting resulted in the largest increase in nodulation but P application produced the greatest gain in seedling weight. Molybdenum interacted with P to enhance seedling nodulation more than either element applied alone. Phosphorus also interacted with Mg to increase seedling weight more than either one applied alone. Sulphur had no influence on seedling nodulation or yield. Applications of B, Cu and Zn depressed nodulation and yield, possibly because excessively high levels were applied. Using lime‐pelleted seed and a fertilizer combination of K. Mg. Mo and P could improve white clover establishment and growth on permanent‐pasture soils in the northeast.
An analysis of the uninterrupted growth of white clover swards receiving either biologically fixed nitrogen or nitrate in solution
Authors: ARNOTT R. A. 
Published: April 2006

AbstractWhite clover swards were grown in a freely ventilated glasshouse during August and September 1979. The uninterrupted growth of these swards, which were grown in Perlite with either nitrate or biologically fixed nitrogen, was studied from 5 weeks after sowing until peak dry weights of the live sward components occurred. The dry weight of leaf laminae, petioles, stolons, roots, nodules and dead material was determined weekly together with live leaf numbers and leaf lamina area. The pattern of dry matter accumulation of the yield components of the swards (live leaf laminae plus petioles) was characterized by an initial period of more or less exponential growth up to 6 weeks from sowing dominated by leaf lamina development. This was followed by a linear phase, when petiole weight increased rapidly and a final slowing down period terminated by peak yields of live DM 12 weeks after sowing.The weight of stolons, roots and nodules increased slowly during the period dominated by leaf lamina growth compared with the rapid increase thereafter, which resulted in a two‐ to three‐fold increase in the weight of stolons, roots and nodules by the time the weights peaked. It is assumed that after the leaf area index of the sward had reached a plateau there was a limit to the assimilate supply to the sward components at a stage when they were all apparently competing for photosynthates. There was a progressive slowing down in the rate of dry matter accumu‐
Set stocking, rotational grazing and forward rotational grazing by sheep on western Oregon hill pastures
Authors: WARNER J. R. , SHARROW S. H. 
Published: April 2006

AbstractData on sheep live weights, herbage standing crop and herbage quality are presented from a 3‐year grazing management study comparing set stocking, four‐paddock rotational grazing and four‐paddock forward rotational grazing systems. In both rotational grazing and forward rotational grazing systems, sheep were sequentially moved from one paddock to the next every 5 days. Lambs were weaned at 12–15 weeks of age in the forward rotationally grazed system and from then on grazed one paddock ahead of the ewes. Herbage mass was consistently greater on the rotationally grazed system than on the set‐stocked system, averaging 38.4% more herbage in 1978. 32.8% more in 1979 and 52.7% more in 1980. No differences were observed in ewe live weights at the end of the grazing year between the rotationally grazed and the set stocked systems. Live weights of rotationally grazed lambs were superior to set‐stocked lambs only when herbage allowance was low; otherwise no difference existed between these two systems. The forward rotationally grazed lambs generally had lower liveweights than did the rotationally grazed lambs, perhaps due to weaning stress.
Further development and use of an automatic recording system in sheep grazing studies
Authors: PENNING P. D. , STEEL G. L. , JOHNSON R. H. 
Published: April 2006

AbstractComparisons between some aspects of grazing and ruminating behaviour by sheep recorded automatically and by manual observation are reported.Behaviour was recorded manually and automatically on four swards with surface heights of 3, 6, 9 and 12 cm. The automatic recording method gave significantly higher biting rates (78 v 67 ± 2·4 bites min−1) than manual recording. Possible reasons for these differences are discussed. For recordings during ruminating there was no significant difference between the two recording methods.As sward surface height increased biting rate decreased by 4·6 (± 0.65) and 2·9 (± 0·87) bites min−1 cm−1, and masticating rate increased by 4·5 (± 1·13) and 3·7 (± 0·95) chews min−1 cm−1 for the manual and automatic recording methods respectively.It is concluded that the automatic recording system gives higher rates for jaw movements during grazing than manual recording but there is little difference between the two methods for activities recorded during ruminating.
Effects of defoliation intensity on white clover seedling growth
Authors: BOATMAN N. D. , HAGGAR R. J. 
Published: April 2006

AbstractWhite clover seedlings were defoliated when either two, four or six leaves had opened. There were four defoliation treatments, involving removal of younger laminae, older laminae, all laminae or all laminae and petioles, plus a control (no defoliation).Leaf removal reduced area of subsequently emerging leaves when measured as they became fully opened, though some compensatory expansion occurred after this. Petiole length was also reduced considerably. The magnitude of these effects varied according to severity of the treatment: removal or older laminae had little effect, removal of younger laminae had a similar effect to removing all laminae, but the effect was considerably increased by removing petioles in addition to laminae. The youngest plants showed the greatest reductions in leaf size following leaf removal. Defoliation had little effect on the rate of development of subsequent leaves.The most severe defoliation treatments reduced plant dry matter but younger seedlings appeared to have a capacity for recovery equal to or greater than that of older seedlings.It is concluded that white clover seedlings have a considerable ability to recover from leaf removal, especially if only laminae of old leaves are removed, but the growth reduction following removal of petioles as well as laminae appears to be especially severe.
Influence of some sward characteristics on the consumption of irrigated pastures grazed by lactating dairy cattle
Authors: STOCKDALE C. R. 
Published: April 2006

AbstractPasture variables measured in eight experiments at Kyabram, Victoria were used to quantify factors influencing the consumption of irrigated pastures grazed by dairy cows. In addition, whether intake prediction equations based on sward characteristics could be developed and applied in the field was also considered.Herbage intake (DMI) was positively related to herbage allowance (HA) in all cases; however, the increase in daily DMI achieved for every additional kg herbage offered to a cow ranged from 015 to 0·35 kg. Herbage intake was also consistently related to residual herbage (RH). For every additional tonne herbage dry matter (DM) ha−1 remaining after grazing, each cow consumed increased daily amounts of herbage ranging from 3·2 to 5·1 kg DM. However, of the other pasture variables, herbage mass (HM), pasture type (PT) and digestibility of the herbage DM on offer (DMD) influenced herbage intake less consistently.When the data from all experiments were included together, DMI was influenced by sward characteristics in the following manner:
image
where LW = live weight of the cow (kg) and DE = duration of experiment (d).When RH was considered instead of HA, only 61% of the variability in intake was accounted for compared to 80% when HA was considered:
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In both of these equations, two variables other than the sward characteristics were significant; these were LW and DE. The significance of these variables in these relationships are discussed together with the possibility of using them for predicting DMI in other environments. However, it is concluded that they do not have general applicability and it is suggested that they may be useful only in the environment in which they were generated.
The future of lucerne in British agriculture: an economic assessment
Authors: DOYLE C. J. , THOMSON D. J. 
Published: April 2006

AbstractWith its potential for high yields and high animal output, lucerne appears to be an underexploited crop in British agriculture. In this paper an attempt is made to assess the prospects for expansion of the area of lucerne in Britain from an economic viewpoint, concentrating on lucerne as a conservation crop. Under good management lucerne is shown to have lower production costs than grass and its inclusion in the diet of dairy cows, but not beef cattle, could significantly lower winter feed costs. However, under apparently similar growing conditions, lucerne yields on different farms vary significantly, ranging from 9 to 13 t dry matter ha−1 a−1. At the lower yields, the economic attraction of growing and feeding lucerne in place of grass is small. Moreover, since potential lucerne production is concentrated in the south and east of Britain, lucerne competes with other arable crops. For lucerne to offer a gross margin per unit area comparable with these, the price for conserved lucerne would have to be set at a level at which dairy farmers would derive little economic advantage from feeding it. Thus, although lucerne is a forage crop with some potential, at present it is likely to offer economic possibilities only where producers can combine high yields with on‐farm utilization of the crop.
The effect of the growth regulator paclobutrazol (PP333) on the growth, development and yield of Lolium perenne grown for seed
Authors: HAMPTON J. G. , HEBBLETHWAITE P. D. 
Published: April 2006

AbstractApplication at spikelet initiation of the growth retardant paclobutrazol (PP333) at a rate of 2.0 kg a.i. ha−1 increased the seed yield of perennial ryegrass cv. S24 from 139 to 180 g m−2 in 1981, and from 111 to 256 g m−2 in 1982. Yield increases were associated with an increased production of fertile tillers in both years and with an increased number of seeds per spikelet in 1982. Other yield components were not changed. Seed yield increased with increasing PP333 application rate in both years. No significant yield difference was recorded between application at spikelet and floret initiation in 1981.Lodging was prevented completely by the 2.0‐kg rate, delayed until after anthesis by the 1.0‐kg rate and began before anthesis with the 0.5‐kg rate. PP333 reduced stem internode length and strengthened the base of the stem; total stem dry matter (DM) was reduced, but root DM accumulation was increased at all rooting depths. Leaf area duration was significantly increased in both years.Vegetative regrowth after seed harvest was not significantly reduced by PP333 application, but soil residual properties were demonstrated.
Eating behaviour, social dominance and voluntary intake of silage in group‐fed milking cattle
Authors: HARB M. Y. , REYNOLDS VIVIEN S. , CAMPLING R.C. 
Published: April 2006

AbstractThe relationships between eating behaviour, social dominance and voluntary intake of silage were examined in three experiments. Small groups of Friesian cattle were offered forage as a group in several different situations which caused different degrees of competition for silage. Restriction of the number of mangers available to the cows and of the amount of silage offered encouraged a marked increase in rate of eating silage. In Experiment I when the cows were changed from individual mangers to group feeding their mean eating rate of silage increased from 43 to 71 g silage dry matter min−1. Results from the second experiment provided confirmation. In both experiments submissive cows increased their rate of eating to a greater extent than dominant animals. When group‐fed there was no significant correlation between degree of dominance and variation between cows in voluntary intake of silage, but milk yield and live weight were often directly correlated with silage intake. In Experiment 3 cows and heifers ate similar amounts of silage per unit live weight when group‐fed.
The microclimate of an upland grassland
Authors: HAY R. K. M. 
Published: April 2006

AbstractContinuous hourly measurements of air and soil temperatures, irradiance and wind velocity, and less frequent measurements of soil water status and dry matter (DM) yield were recorded over two growing seasons and the intervening winter 1978–79 for an enclosed upland grassland in Cumbria, with the aim of establishing realistic combinations of environmental factors for the design of experiments under controlled conditions. Important features of the microclimate included high diurnal and day‐to‐day variation in environmental temperature, relatively high winter soil temperatures, variation between years in the influence of altitude upon irradiance, low wind velocity throughout the year at plant height and the loss of DM yield in the early summer of 1978 due to severe drought. Combinations of environmental factors throughout the 2 years can be obtained from the figures presented; in particular, the records indicate that in growth‐cabinet or greenhouse experiments associated with the breeding or selection of cultivars for earlier DM production in spring, it is important to combine low temperatures (≤ 10°C) with realistic levels of irradiance (≥200 W m−2) and daylength (12.5–15 h).
In‐vitro dry matter digestibility and chemical composition of autumn‐accumulated tall fescue, orchardgrass and red clover
Authors: SHEEHAN W. , FONTENOT J. P. , BLASER R. E. 
Published: April 2006

SummaryThe objective of this study was to compare the in vitro dry matter digestibility (IVDMD) and chemical composition at various cutting dates of autumn‐accumulated tall fescue and orchard‐grass. The effect of time on the digestibility and chemical composition of accumulated red clover was also studied.Tall fescue had significantly higher (P< 0.01) IVDMD and total non‐structural carbohydrate (TNC) levels and lower crude protein (CP), acid‐detergent fibre (ADF). lignin (LIG) and cellulose (CEL) levels throughout autumn and winter than orchardgrass. The effects of accumulation period were similar on both grasses; TNC concentrations increased up to November but then declined, with a large drop in levels after December while IVDMD decreased slowly in autumn and fell rapidly in December. Overall there was a significant (P< 0.01) increase with advancing time in ADF and CEL levels in both grasses, but LIG levels declined with age in tall fescue between 15 September and 15 November, whilst there was a general increase in LIG in orchardgrass.In both tall fescue and orchardgrass IVDMD and TNC levels were higher (P< 0.001) and CP, ADF and CEL levels lower (P< 0.001) in the stem than in the leaf. LIG concentrations were higher in orchardgrass leaves than in the stem but the levels were similar in both fractions in tall fescue.Similar patterns of change in IVDMD and composition were evident in red clover but the legume had completely senesced by early winter.
The effect of the brown midrib‐3 gene on the maturity and yield of forage maize
Authors: WELLER R. F. , PHIPPS R. H. , COOPER A. 
Published: April 2006

AbstractResults from two trials with normal and brown midrib‐3 (bm3) types of LG11, Inra 188, Inra 240 and Inra 258 showed the bm3 mutant gene delayed silking by an average of 3 days, decreased whole plant dry matter (DM) concentration by 20 g kg−1 and the proportion of ear by 4·6 percentage units. Comparable yields of DM were obtained from normal and bm3 crops. The organic matter digestibility and yield of digestible organic matter of the bm3 plants was 0.06 units and 14% higher respectively than their normal counterparts.Measurement of the physical strength and resistance to lodging of normal and bm3 plants showed the bm3 gene reduced stem strength, which was highly correlated to stem diameter, stem weight and rind thickness. However, the major difference in plant lodging was between genotypes with Inra 240 plants less resistant to lodging than other genotypes. These results show that although the bm3 gene slightly increased lodging, genotype susceptibility is the major contributing factor to plant lodging.
Nutrient content and phenology of cool‐season grasses of Peru*
Authors: FLOREZ A. , MALPARTIDA E. , BRYANT F. C. , WIGGERS E. P. 
Published: April 2006

AbstractChanges in crude protein (CP) concentration and in vitro dry matter digestibility (IVDMD) associated with phenological development were documented for eight major cool‐season grasses on the Pampa Galeras Vicuna Reserve in the central Andes of Peru. Green‐up for most grasses occurred by late November and seed shatter occurred by late May for an average of 185 days from initiation of growth to maturation. CP and IVDMD levels were adequate for animal production from November to January for most grass species and until March for Muhlenbergia ligularis and Stipa brachyphylla. The data suggest domesticated ruminants should be managed so that greatest nutrient requirements (late gestation‐lactation) will coincide with the period of highest nutritional quality of the native grasses (November–January).
Effect of restriction of silage intake and the provision of an alternative forage on the performance of dairy cows
Authors: PHILLIPS C. J. C. , LEAVER J. D. 
Published: April 2006

AbstractIn three experiments the effects of restricting the silage ration of dairy cows and of offering alternative forages as buffer feeds were investigated.In the first experiment of changeover design with 3‐week periods, restricting the intake of low‐quality silage to 0.62 of ad libitum had no significant effect on milk yield in spite of the large energy deficit. Offering high‐quality hay as a buffer feed increased total DM intake and milk production of cows receiving either restricted or ad libitum silage.In the second experiment of similar design, restricting the DM intake of high‐quality silage to 0·58 of ad libitum significantly reduced milk yield and was associated with a large negative energy balance. Offering straw or ammonia‐treated straw with the restricted silage diet did not restore milk production to the level achieved with ad libitum silage but these supplements slightly reduced the energy deficit of the cows. In the third experiment of continuous design lasting 7 weeks, restricting the silage ration to 0.85 of ad libitum had no significant effect on milk production. Offering a strawmix based on straw, barley, molasses and soya with the restricted silage ration restored total DM intake to the ad libitum silage level.In all three experiments milk protein content was reduced by restricting the silage ration and partially restored by offering alternative forages. There were no significant effects on milk fat content and milk lactose content was only reduced by the severest restriction in Experiment 2. It is concluded that short‐term minor restrictions of silage intake can be partly sustained by body fat mobilization but more severe restrictions will result in loss of milk yield. Good‐quality hay and a strawmix were of benefit in restoring DM and metabolizable energy intakes, whereas straw and ammonia‐treated straw were of little value.
Long‐term effects of fertilizer on the botanical composition and soil seed population of a permanent grass sward
Authors: WILLIAMS E. D. 
Published: April 2006

AbstractResults are presented after 14 and 19 years of the botanical composition and seed bank of moderately fertilized or unfertilized grazed paddocks. Agrostis capillaris, Festuca rubra and broad‐leaved weeds contributed a larger proportion of the cover on unfertilized than on fertilized swards. In contrast Poa spp., Holcus lanatus, Alopecurus pratensis and Lolium perenne were relatively more abundant on the fertilized than on the unfertilized swards. A. capillaris was the most plentiful grass in the seed bank of the unfertilized swards but Poa spp. (especially P. annua) in that of the fertilized swards. Some of the relationships between the seed bank and vegetative cover are discussed and the possibility of further increasing the contribution of L. perenne highlighted.
Effect of time of application of nitrogenous fertilizer on development of white clover in an autumn‐sown mixed sward
Authors: LAIDLAW A. S. 
Published: April 2006

AbstractNitrogenous fertilizer was applied to autumn‐sown swards (soil N MAFF index 1) containing perennial ryegrass (cv. Cropper) and white clover (v. Huia) either at sowing or when nodulation was underway (38 days after sowing) at 0, 30, 60 or 120 kg N ha−1. Each treatment received 0, 45 or 90 kg ha−1 the following spring.Nitrogen at sowing or nodulation had no effect on net rate of growth of clover plants but increased the mean number of initiated stolons per plant (mean of 17% more than unfertilized controls in late autumn) and decreased the rate of N2 fixation until late in autumn. Seed‐bed N had a greater reducing effect on N2 fixation than N applied at nodulation. Nitrogen at sowing also reduced the nodule number per plant.Response of DM to N was not significant at the establishment harvest but was significant at the first harvest in the next year. The response to autumn applied N was lower than that to N applied in spring.It is concluded that applied N is unlikely to be necessary for grass‐clover seed beds with an N index of 1.
The effect of harvesting system on nutrient losses during silage making. 1. Field losses
Authors: MAYNE C. S. , GORDON F. J. 
Published: April 2006

AbstractAn experiment was carried out during 1982 in which the effects of three differing harvesting systems on the field losses occurring during the conservation of grass as silage were examined. The treatments were either (a) harvesting herbage directly by means of a flail harvester (unwilted flail, UF), or (b) pre‐cu ing of herbage with a rotary drum mower and lifting using a precision‐chop forage harvester with wilting (WP) and without wilting (UP). Herbage was harvested on 26 May, 21 July and 7 September 1982. The mean yields of herbage produced from plots harvested by the three systems were not significantly different, with dry ma er (DM) yields of 12470, 12300 and 12230 kg ha‐1 for the UF, UP and WP treatments respectively. However, field losses with the UP and WP treatments were greater than with the UF treatment (P<0·01). As a result the yields of herbage ensiled with the UP and WP treatments, 11690 and 11320 kg DM ha‐1 respectively, were significantly lower than with the UF treatment, 12710 kg DM ha‐1 (P <0·05). Wilting of first cut herbage for a period of 72 h resulted in a significant reduction (P<0·05) in digestible organic ma er (DOM) concentration (determined in vitro), whereas small increases in DOM concentration were observed following wilting of second and third harvest material.It is concluded that, even under favourable weather conditions, both pre‐cutting and wilting of herbage prior to harvesting can result in considerable losses of nutrients in the field.