bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of the field drying of herbage on sward regrowth
Authors: OWEN I. G. , WILMAN D. 
Published: April 2006

AbstractGrass which had grown without interruption from late April was cut as for hay in early July in each of 2 years. Fifteen dates of removal of the cut herbage were compared ranging, at 1‐d intervals, from the day of cutting to 14 d after cutting. Sward regrowth was studied.A delay of 5 d in removing cut herbage reduced herbage dry matter harvested during the remainder of the growing season by 9% and a delay of 10 d reduced yield by 16%. Delaying the removal of cut herbage reduced the density of grass tillers considerably in the short term, but the effect had worn off in 8 to 12 weeks. The presence of cut herbage reduced the rate of extension of leaf blades considerably. Delaying the removal of cut herbage reduced the area per leaf blade and the weight per unit area and these effects persisted for several weeks. Grass growing under cut herbage had a less negative leaf water potential and a rather cooler but much darker environment in which to grow than uncovered grass.
The susceptibility of agricultural grasses to pre‐emergence damage caused by Fusarium culmorum and its control by fungicidal seed treatment
Authors: HOLMES S. J. I. 
Published: April 2006

AbstractA total of 104 cultivars of six agricultural grass species were compared under controlled conditions for their relative susceptibility to the common soil‐borne fungus Fusarium culmorum (W.G.Sm.) Sacc. A number of the perennial ryegrass (Lolium perenne) cultivars showed a high degree of resistance, their emergence being little reduced under the stringent test conditions. The emergence of others was, however, severely affected. Italian ryegrass (L. multiflorum) cultivars generally had a high level of resistance, the outstanding exception being cv. Leda Daehnfeldt which proved very sensitive. None of the cultivars of cocksfoot (Dactylis glomerata), timothy (Phleum pratense), meadow fescue (Festuca pratensis) or tall fescue (F. arundinaceae) which were tested had more than a moderate level of resistance and most were highly susceptible.The vigour of ryegrass seedlings was, in most cases, closely correlated with percentage emergence but was less closely correlated in the more susceptible species. These often had a very low emergence but those seedlings which did establish were frequently of a size similar to that of healthy plants.Treatment of grass seed with a fungicide mixture of benomyl (15% a.i.) plus captan (60% a.i.) provided excellent protection against F. culmorum on even the most susceptible cultivars.Drazoxolon (40% a.i.) was, however, much less effective.
In vitro digestion of bundle sheath cells in rumen fluid and its relation to the suberized lamella and C4 photosynthetic type in Panicum species
Authors: WILSON J. R. , HATTERSLEY P. W. 
Published: April 2006

AbstractDifferences in ease of digestion of bundle sheath cell walls of leaf blades of Panicum spp. are shown to be associated with differences in bundle sheath cell wall structure, including the presence or absence of a suberized lamella. These structural differences are correlated with photo‐synthetic type (viz. C3, intermediate C3/C4, and the C4 types, PCK, NADP‐ME and NAD‐ME), as are mesophyll: bundle sheath area ratios.
The influence of sward condition on rates of herbage growth and senescence in mixed swards under continuous stocking management
Authors: BIRCHAM J. S. , HODGSON J. 
Published: April 2006

AbstractA study was conducted to determine the influence of herbage mass under continuous stocking management with sheep on rates of herbage growth (G), senescence (S) and net production of green herbage (NP) in a mixed‐species sward of Lolium perenne. Poa annua and Trifolium repens. Plots were maintained in as nearly constant herbage mass as possible at 500, 700, 1000 and 1700 kg organic matter (OM) ha−1 by continuous but variable stocking with sheep for the period May to July inclusive. Estimates of G, S and NP were obtained for each species from repeated measurements over two 2‐week periods on individually identified grass tillers or clover stolons. Estimates of species population densities enabled estimates of G. S and NP per unit area to be made.Rates of G were higher and of S were lower for Lolium tillers and Trifolium stolons than for Poa tillers. The laminae of Poa tillers occupied inferior positions in the canopy of the swards maintained at higher herbage masses and were less accessible to the grazing animals, so that Poa tissue was less well utilized.The total population densities of tillers and stolons declined at herbage masses both above and below 700 kg OM ha−1. The rate of G for the three species combined increased with herbage
Sward management, lamina turnover and tiller population density in continuously stocked Lolium perenne‐dominated swards
Authors: GRANT S. A. , BARTHRAM G. T. , TORVELL L. , KING J. , SMITH H. K. 
Published: April 2006

AbstractMeasurements of rates of growth and senescence of leaf lamina per tiller and of changes in tiller population densities were made in three experiments designed to investigate the influence of sward slate on leaf turnover and net production under continuous stocking.In each experiment initially uniform swards were fenced to provide four plots on which animal numbers were adjusted twice weekly to give a series of swards maintained as nearly as possible in a steady state with respect to sward surface height (range 1.1–6.4 cm) and herbage mass (range 440–2690 kg OM ha−1). Two experiments were carried out in July–September on vegetative swards and one in May–June on a reproductive sward. Measurements were begun 3–7 weeks after treatments were started and were repeated weekly during 3–4 week measurement periods.In all three experiments the rate of lamina growth per tiller increased linearly with an increase in sward surface height and herbage mass. In the two experiments conducted in July–August this relationship was partially offset by a linear increase in the rate of senescence per tiller but net production per tiller also increased linearly in relation to sward height and mass. In the experiment conducted in May–June the rates of growth and senescence per tiller increased in parallel so that net production per tiller showed no relationship with sward condition.Tiller population densities in the July–August experiments were highest in swards maintained between 2 and 3 cm surface height and declined in swards maintained above and below this height. In the experiment in May–June tiller numbers were similar in all treatments prior to the summer solstice but diverged in a manner similar to the other experiments later in the year.The rate of lamina growth per unit area increased in a manner consistent with an asymptotic relationship and the rate of senescence increased linearly with increasing sward height and mass in all three experiments. Net production per unit area was reduced on swards below about 2.5 cm in height but was insensitive to variation in sward surface height between 2.5 and 6.0 cm (approximately 1000–2500 kg OM ha−1 herbage mass).The effectiveness of adjustments in tiller numbers and production per tiller and of changes in the balance between growth and senescence as mechanisms of sward homeostatis, together with their implications in the scope for manipulating herbage production by grazing management are discussed briefly.
The effect of stocking rate on a lamb production system with February‐lambing ewes
Authors: ORR R. J. , NEWTON J. E. 
Published: April 2006

AbstractMasham ewes were stocked at 12(L), 16(M) or 20 (H) ewes ha−1, with 1·8 lambs per ewe on average, on two blocks (A and B) in both 1976 and 1977. Silage was offered at pasture to the ewes in early lactation and as stocking rate increased from 12 to 16 and then 20 ewes ha−1, 47, 73 and 100 kg DM per ewe was consumed respectively. Silage was cut mainly in the autumn and 179, 100 and 9 kg per ewe was made for L, M and H respectively. More variation between treatments was measured in net herbage accumulation in summer than spring and 11·4, 10·0 and 9·7t DM ha −1 was grown over the whole season for L, M and H respectively as a mean of both years.High intakes of herbage OM were measured with values up to 40 g per kg live weight for BL lambs in 1976. Rapid lamb growth was achieved. There were effects of stocking rate on lamb performance and for L, M and H the respective growth rates to 4 weeks were 266, 248 and 247 g d−1; growth rates to sale were 274, 263 and 252 g d−1; days to sale were 124, 126 and 129; mean carcass weights were 17·7, 17·1 and 16·7 kg. Most ewes lost weight in early lactation, especially AH and BH in 1976, but there were no stocking rate effects on ewe weight change in 1977.
A comparison of unwilted and wilted grass silages offered to beef cattle without and with monensin sodium
Authors: STEEN R. W. J. 
Published: April 2006

AbstractA randomized block experiment was conducted to compare unwilted and wilted grass silages and the effects of the feed additive monensin sodium on the silage intake and performance of finishing beef cattle. Two regrowths from a predominantly perennial ryegrass (cv. S24) sward were ensiled either without wilting or after field wilting for 3 d (dry matter (DM) concentrations 161 and 266 g kg−1 respectively). Both silages were treated with formic acid (2·6 and 30 litre t−1 respectively) and were well preserved. The silages were offered ad libitum to forty‐eight Charolais‐cross cattle (thirty‐two steers and sixteen heifers, mean initial live weight 351 kg) for 145 d. All animals received 2·2 kg concentrates per head daily and half of those on each silage treatment received in addition 200 mg monensin sodium per head daily. Silage DM intake was 5.04, 504. 5·48, 5·63 ± 0.134 kg d−l; fasted liveweight gain was 0·69, 0·77. 0·64 and 0·73 ± 0.033 kg d−l and carcass gain was 0·47, 0·50, 0·40 and 0·45 ± 0·020 kg d−1 for the unwilted silage without and with monensin and the wilted silage without and with monensin respectively. It is concluded that wilting grass of low DM concentration for 3 d prior to ensiling reduced the performance of finishing beef cattle below that obtained from well‐preserved unwilted silage in spite of a higher DM intake being achieved with the wilted silage. The inclusion of monensin sodium in a silage‐based diet increased performance without significantly affecting feed intake.
The antimicrobial spectra of organic compounds with respect to their potential as hay preservatives
Authors: WOOLFORD M. K. 
Published: April 2006

AbstractFormic acid, sodium diacetate, propionic acid and two of its ammonium salts, ammonium isobutyrate and tributyl phosphate, were examined for their antimicrobial effects with cultures of micro‐organisms typical of the microflora of moist hay. The assays, which were conducted at pH 5, 6, 7 and 8, revealed that all potential preservatives discriminated against actinomycetes in particular and were least effective against fungi. In addition, it was apparent that antimicrobial properties were enhanced under slightly acid conditions and for this reason the use of mixtures of organic acids and salts in commercial hay preservatives is justified. Tributyl phosphate not only had the strongest antimicrobial properties of the compounds tested but was also the least affected by pH.
The effects of change in herbage mass on rates of herbage growth and senescence in mixed swards
Authors: BIRCHAM J. S. , HODGSON J. 
Published: April 2006

AbstractA study was conducted to determine the influence of a change in herbage mass on rates of herbage growth (G), senescence (S) and net production of green herbage (NP) in swards of Lolium perenne L., Poa annua L. and Trifolium repens L. under continuous stocking with sheep. Swards were maintained at either high (1700–1900 kg OM ha−1; H) or low (700–900 kg OM ha−1; L) herbage mass from April to 20 August. From 20 August to 13 September half of the L sward was permitted to grow until a herbage mass similar to that of the H sward was achieved (LH), and at the same time half of the H sward was grazed down until a herbage mass similar to that of the L sward was achieved (HL). The other half of each sward was held at constant mass (LL and HH). Estimates of G, S and NP were obtained for each plant species over a 2‐week period from 17 September to 1 October and estimates of species population densities were also made.The combined species rates of G and S per unit area were highest in treatment LH and lowest in treatment HL, whilst the rates for the LL and HH swards were intermediate. The rate of NP was similar in the LL, HH and LH treatments (34.5, 29.3, 33.6 ± 6.2 kg DM ha−1d−1) but was lower in the HL sward (100 ± 6.2). The effects of alteration of herbage mass on individual tiller or stolon G and S rates were rapid but population density changes were slower.Within the limited conditions of this trial it was not possible to increase NP by manipulation of herbage mass under continuous stocking management but the results indicate that NP can be reduced in the short term if a sward of high herbage mass and low population density is grazed hard.
Silage and milk production: a comparison between unwilted and wilted grass silages
Authors: CASTLE M. E. , WATSON J. N. 
Published: April 2006

AbstractThree grass silages made in sunny weather in early July from second‐harvest perennial ryegrass were compared in a 16‐week feeding experiment with twelve Ayrshire cows. The silages were either unwilted or wilted with and without conditioning, and had mean dry matter (DM) concentrations of 201, 261 and 272 g kg−1, and in vitro DOMD concentrations of 650, 669 and 672 g kg−1 DM respectively. All the silages had formic acid (‘Add‐F’) applied at a rate of 2.6 litres t−1 and were offered ad libitum plus 6 kg concentrates per cow per d. The daily intakes of silage DM were 905 kg per cow on the unwilted treatment and 9.86 and 9.65 kg on the wilted treatments with and without conditioning respectively. Daily milk yields were 171, 17.6 and 17.4 kg per cow on the unwilted, and wilted with and without conditioning treatments respectively and were not significantly different. Fat concentrations in the milk were not affected significantly by treatment, whereas the crude protein and solids‐not‐fat concentrations were significantly higher on the wilted than on the unwilted treatment. The efficiency of utilization of metabolizable energy for lactation was 6–7% lower with the wilted than with the unwilted silages and it is concluded that the unwilted silage was superior to the wilted silages as a feed for dairy cows.
A system for rapid freezing of pasture samples in the field
Authors: COLEBROOK W. F. , JAMES K. J. , HAMILTON W. J. 
Published: April 2006

AbstractA system for rapid freezing and containment of pasture and forage samples in the field is described. Core temperatures of pasture samples of 2–5 kg mass can be reduced to below 0°C in a few minutes using liquified carbon dioxide in the ratio of 1 to 2 kg carbon dioxide to 1 kg of green plant material. Changes in the pH of the plant extract were very small (ca. 0 1 pH unit). The system is especially suitable for use in areas remote from normal laboratory facilities, where rapid freezing of herbage samples is essential.
The utilization of sown and indigenous plant species by sheep and goats grazing hill pastures
Authors: GRANT SHEILA A. , BOLTON G. R. , RUSSEL A. J. F. 
Published: April 2006

AbstractThe utilization of sown and indigenous plant species was studied in three experiments in which plots were stocked with similar live weights of sheep and goats. In the first experiment the animals grazed plots containing 0–5 ha of rush (Juncus effusus)‐ infested reseeded pasture and 0–5 ha of unimproved blanket bog. The second and third experiments took place on old rush‐infested improved pasture; in one experiment two levels of herbage mass of grass were provided while in the other the rushes were cut in spring or remained uncut.The goats grazed the rushes readily in all three experiments. Reduction in herbage mass of grass increased utilization of rushes by goats although these animals still grazed rushes when grass supply was plentiful. Sheep scarcely grazed J. effusus even when hard‐pressed by shortage of grass. Both sheep and goats grazed J. acutiflorus.In Experiment I sheep utilized reseeded pasture more heavily than did goats. Sheep grazed similar proportions of the leaves of grass and clover while goats grazed a lower proportion of clover leaves as compared with grass. Among the grasses sheep discriminated in favour of Lolium perenne whereas goats did not. On the blanket bog vegetation, Eriophorum vaginatum and Calluna vulgaris were grazed both earlier in the season and more heavily by goats than by sheep.The relationships between sward structure and grazing height in accounting for differences in species selection by sheep and goats are briefly discussed. The possibility of using goals to control coarse weeds in hill pasture and for strategic grazing to manipulate floristic composition is outlined.
Growth rate, senescence and photosynthesis of ryegrass swards cut to maintain a range of values for leaf area index
Authors: KING J. , GRANT S. A. , TORVELL L. , SIM E. M. 
Published: April 2006

AbstractAn experiment was carried out in which simulated swards of ryegrass (cv. S23) were grown in boxes. In the first instance the swards were cut at weekly intervals to maintain five levels of leaf area index (LAI) from LAI 1 to 4–5 in simulation of continuous grazing. Measurements were made of growth, senescence and net growth rate and of net canopy photosynthesis at constant irradiance. The results showed that the swards adapted to the defoliation regimes mainly by changes in tiller population density and pseudostem length. When the swards had equilibrated to the cutting regime growth rate increased with LAI but, since tiller density and the partitioning of growth between herbage harvested and that lost by sensecence also changed with LAI, net growth rate was constant over the LAI range 2–4·5. Maximum weight of herbage harvested was obtained between LAI 2 and 3.After 10 weeks of weekly cutting all the swards were cut back to LAI 1 and allowed to regrow. Growth rate showed almost no response to the previous culling treatments. The relationship of net canopy photosynthesis to LAI was linear for the frequently defoliated swards and curvilinear for regrowing swards. The reasons for this difference were examined.
The effect of cutting for conservation on a grazed perennial ryegrass‐white clover pasture
Authors: CURLL M. L. , WILKINS R. J. 
Published: April 2006

AbstractContinuous stocking with sheep at high stocking rates may reduce the content of white clover (Trifolium repens) in mixed grass‐clover swards. The present experiment was carried out to investigate the effects on sward production and composition of resting a perennial ryegrass (Lolium perenne)‐ white clover sward from grazing and taking a cut for conservation.Swards were set‐stocked with 25 and 45 yearling wethers ha−1 either throughout a grazing season, or on swards that were rested for a 6‐week period and then cut in early, mid‐ or late season. In an additional treatment swards were cut only and not grazed.Net herbage accumulation was higher at the lower of the two stocking rates and was marginally increased by the inclusion of a rest period at the high but not the low stocking rate. Clover content was higher at the lower stocking rate and was increased by the inclusion of a rest period by 30% at 45 sheep ha−1and by 11% at 25 sheep ha−1 The effect was most marked at the end of the rest period before cutting. When rested from grazing the tiller density of ryegrass decreased although tiller length increased, and clover stolon length, petiole length and leaflet diameter increased though leaf and node number per unit length of stolon decreased; the reverse applied when the sward was returned to grazing after cutting.At the high stocking rate, rest periods in mid‐season or later maintained the greatest clover content and marginally increased total net herbage accumulation. At the low stocking rate the timing of the rest period had no significant effect on total net herbage accumulation or on clover content.These results show that the combination of grazing and cutting is of benefit where the stocking rate is high enough to threaten clover survival and limit sheep performance. However, at such a stocking rate, feed reserves are at a minimum throughout the grazing season and so opportunities for resting the sward are probably low.
Variation among pregnant, non‐lactating dairy cows in eating and ruminating behaviour, digestibility and voluntary intake of hay
Authors: Harb M. Y. , Campling R. C. 
Published: April 2006

AbstractThe variation between non‐lactating British Friesian cows in eating and ruminating pattern, digestibility and voluntary intake of hay were measured about 4 weeks before calving. Among fourteen of the cows the daily duration of eating ranged from 214 to 462 min and rumination from 410 to 599 min with CV of 20 and 14 respectively. Daily hay intake varied between cows from 5.93 to 11.18 kg dry matter (DM) with a CV of 14. The mean digestibility coefficient of organic matter measured in nineteen cows was 0.57 ± 0.014 s.d. and of cellulose 0.70 ± 0.013 s.d. Intake of hay and cellulose digestibility were correlated (r = 0.51, P<0.05). There was a positive correlation between hay intake and duration of eating (r=0.64, P<0.01) but not between intake of hay and rate of eating. Daily time spent ruminating per kg hay DM eaten was negatively correlated with hay intake (r = 0.66, P<0.01). It is concluded that variation between cows in chewing time and in digestibility of cellulose may be important factors related to variation between cows in voluntary intake of hay.
A comparison of faba beans and peas as whole‐crop forages
Authors: FAULKNER J. S. 
Published: April 2006

AbstractFaba beans and peas were compared as spring sown whole‐crop forages in two trials at Lough‐gall. No herbicide, insecticide or N fertilizer was used. Harvesting took place at the end of July. As pure stands, tic beans (cv. Blaze) yielded up to 10 t of dry matter (DM) ha−1. Lower yields were obtained at lower seed rates, or with horse beans (cv. Stella Spring), broad beans (cv. Polar) or peas (cvs Minerva and Krupp). Tic and horse bean forage had a mean DM concentration of 166 g kg−1, which was higher than those of broad bean and peas. Crude protein (CP) concentration at a mean of 159 g kg−1 was similar in tic beans and peas. Faba beans mixed with cereals yielded less than beans alone, but peas with cereals yielded slightly more than peas alone. The inclusion of a cereal raised forage DM contents but lowered CP contents. Perennial ryegrass‐white clover mixtures undersown in faba beans established well, but poorer swards were obtained in some of the pure pea stands which lodged severely. It is concluded that, as pure stands, tic beans have advantages over peas. Some of the disadvantages of peas can be overcome by growing a mixture of peas with cereals.