bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of insecticide treatment on the establishment and growth of Italian ryegrass under different sowing conditions
Authors: HENDERSON I. F. , CLEMENTS R. O. 
Published: April 2006

AbstractItalian ryegrass, Lolium multiflorum Lam., cv. RvP., was broadcast in spring on to fine and coarse seedbeds at seed rates of either 2 or 20 kg ha‐1. Each of the four combinations of sowing condition was either left untreated or treated with fungicide or insecticide. The establishment of the sown species and of weeds under each regime was measured and their relative contribution to dry matter assessed in four cuts during the sowing year. Seed rate affected weed invasion and yield more than seedbed condition. Insecticide treatment increased the establishment and yield of ryegrass and its contribution to total herbage yield under all four sowing conditions. The fungicide treatment had no effect. The improvements caused by insecticide treatment were associated with a reduction in the level of infestation by shoot flies, Oscinella spp. (Diptera: Chloropidae): the effect of a single treatment in April was still detectable in October.
The effect of time of initial defoliation and height of defoliation on the productivity of perennial ryegrass swards
Authors: BINNIE R. C. , CHESTNUTT D. M. B. , MURDOCH J. C. 
Published: April 2006

AbstractOver a 3‐year period the productivity of perennial ryegrass (Lolium perenne L., cv. S24) swards as influenced by variations in the time of initial defoliation and close (2·5 cm) and lax (8 cm) defoliation was studied. Treatments with initial defoliations in the early vegetative stage, stem elongation and flowering stages of growth gave higher annual yields than treatments in which the initial defoliation was taken at an intermediate stage of growth when the majority of the stem apices had just been elevated above the height of defoliation. Initial defoliation treatments which removed a high proportion of apical meristems while the yield at the initial defoliation was still low produced the lowest annual yield. Consistent lax defoliation reduced yield by 14·5% compared with continual close defoliation. However, taking an initial lax defoliation followed by subsequent close defoliations produced a slight yield advantage of 4·8% over consistent close defoliation. The results are discussed in relation to other research findings and the practical implications commented upon.
The effect of supplements of fishmeal and lactic acid on voluntary intake of silage by calves
Authors: THOMAS C. , GILL M. , AUSTIN A. R. 
Published: April 2006

AbstractIn order to assess the relative effects of protein content and acid on intake, grass silage was given ad libitum to twelve entire male calves, initially 4 months of age and 117 kg liveweight (LW), either alone or supplemented with fishmeal at 50 g dry matter (DM) per kg silage DM. These two diets were offered alone or with additions of lactic acid at 50 g per kg silage DM in a partial changeover design in which lactic acid levels only were reversed between two 28‐d measurement periods.In the absence of lactic acid, fishmeal significantly increased absolute intake but not intake relative to LW. There was a significant interaction between treatments in that the addition of lactic acid depressed DM intake in the absence of fishmeal (23·9 vs 21·1 g kg‐1 LW) but not in its presence (23·2 vs 23·1 g kg‐1 LW). Addition of fishmeal increased the digestibility of DM from a mean of 0·708 to 0·744 (P < 0·05), of gross energy from 0·646 to 0·694 (P < 0·01) and of N from 0·422 to 0·592 (P < 0·001) but had no significant effect on the digestibility of cellulose (0·766 vs 0·788 for treatments without and with fishmeal respectively). Lactic acid addition had no effect on the digestibility of plant components and, further, interaction effects between treatments were not significant. Supplementation with fishmeal reduced the total time spent eating and ruminating (Ro value) from a mean of 284 to 240 min kg‐1 DM (P < 0·01) and increased urine pH from 8·34 to 8·50. Lactic acid influenced neither Ro value nor urine pH and the interaction effect did not reach significance for these two parameters.The results indicate that the addition of fishmeal can overcome a depressant effect of lactic acid on intake and it is suggested that the responses to treatment were mediated via changes in the ratio of energy to protein supply rather than as a result of treatment effects on digestive efficiency or acid‐base balance.
Effect of herbage allowance on the efficiency of defoliation by the grazing animal
Authors: STUTH J. W. , KIRBY D. R. , CHMIELEWSKI R. E. 
Published: April 2006

AbstractAn experiment examining the relationship of daily herbage disappearance (DHD) and daily herbage allowance (DHA) is described. Cows with calves were grazed at three stocking rates on Kleingrass and Coastal Bermudagrass pastures. DHD and DHA were monitored at 14‐d intervals. A significant positive linear relationship was noted between DHD and DHA (P0·25). Equations derived for Coastal Bermudagrass and Kleingrass were not significantly different and resulted in a combined equation Ŷ= 0·275X + 0·209 with an r2 vaiue of 0·27. As DHA exceeded 6–9 kg DM per 100 kg live weight, efficiency of defoliation by the cows and calves declined.
Variations in herbage mass and digestibility, and the grazing behaviour and herbage intake of adult cattle and weaned calves
Authors: HODGSON J. , JAMIESON W. S. 
Published: April 2006

AbstractTwo experiments are described in which groups of lactating cows, non‐lactating cattle and weaned calves grazed a sequence of swards varying in maturity and herbage mass under strip grazing management at a daily herbage allowance of 60 g dry matter per kg live weight. Lactating cows ate 43% and 76% more herbage than non‐lactating cattle of similar weight in the two experiments but herbage OM intakes per unit live weight by the calves and lactating cows were similar.Variations in diet digestibility and herbage intake in the lactating and non‐lactating cattle with changes in sward conditions were similar. In the first experiment the calves were experienced grazers; the variation in the digestibility of the herbage selected was less in the calves than the adult cattle, but the variation in herbage intake was greater. The calves in the second experiment were younger, and they were inexperienced grazers; their ability to increase herbage intake in response to changing sward conditions was poorer than that of adult cattle, though variations in diet digestibility were similar in all classes.The practical implications of these results are discussed briefly.
An investigation of problems of sward improvement on deep peat with special reference to potassium responses and interactions with lime and phosphorus
Authors: FLOATE M. J. S. , RANGELEY A. , BOLTON G. R. 
Published: April 2006

AbstractIn experiments to determine the minimum fertilizer requirements for improved pasture on deep peat, yields were initially low and declined rapidly. Within 2 years persistence of sown species was poor when only 2·5 t lime ha‐1 was applied. Analytical data suggested that K deficiency and low soil pH were contributory factors. When K was omitted from a composite nutrient solution, clover yield was reduced by 50% when 2·5 t lime ha‐1 was applied but was not significantly reduced with 5·0 t lime. Clover alone produced little response to either P or K separately, but highly significant positive interactions were recorded. Clover, but not ryegrass, responded to K topdressing in field cut‐herbage experiments. There was a 3‐fold increase in ryegrass yield with combined P and K topdressing under grazing; 10 times more N and K were recycled in urine on this treatment than on the control.It was concluded that at least 5·0 t lime, 60 kg P and 80 kg K ha‐1 are required for pasture establishment and that soil pH should be maintained above 5·0 to minimize K requirements. The significance of nutrient cycling and of lime × K and P × K interactions is discussed in relation to the persistence of sown species and the maintenance of improved swards on deep peat.
Competitive effects between ten cultivars of perennial ryegrass and three cultivars of white clover grown in association
Authors: CAMLIN M. S. 
Published: April 2006

AbstractIn an experiment of four years duration, the competitive relationships between three cultivars of white clover (Trifolium repens L.) and ten cultivars of perennial ryegrass (Lolium perenne L.) were studied under a N fertilizer regime of 200–240 kg ha‐1 a‐1. The clover cultivars were selected to embrace the various leaf sizes from medium large to small and the ryegrasses included early, mid‐season and late cultivars with a known range of persistence.During the experiment there was a progressive decline in the contribution of clover, though the different characteristics of each of the clover and ryegrass cultivars produced substantial deviations from the average trend. The clover cultivar Kersey was significantly more aggressive towards the companion grass cultivars than either S100 or S184. It produced consistently greater clover contribution to total yield than the other two cultivars and significantly depressed the yields of some of the companion grass cultivars. There was evidence that compatibility of the ryegrass cultivars with clover was inversely related to persistence; the non‐persistent ryegrass cultivars S321 and Presto consistently produced lower grass yields than the more persistent cultivars and consequently permitted greater clover contribution. In the second and third years yield substitution effects between clover and grass components substantially reduced differences in the total grass‐clover yield.The interactions revealed in the experiment showed that both ryegrass and clover cultivars have the potential to influence each other when in association although, with minor exceptions, total annual yields were similar for all grass and clover mixtures at the moderately high level of N applied.
Variation in forage yield and quality of three cruciferous catch crops grown in southern England
Authors: SHELDRICK R. D. , FENLON J. S. , LAVENDER R. H. 
Published: April 2006

AbstractCruciferous catch crops are an important source of forage, particularly in sheep systems, but due to their late sowing date, commonly July or early August, soil moisture is often a limiting factor in crop establishment and subsequent growth, causing wide variations in yield from year to year. Crops of stubble turnip (Brassica campestris ssp. rapifera), forage rape (B. napus ssp. biennis) and fodder radish (Raphanus sativus) were grown at Hurley between 1969 and 1977. Fodder radish was the most variable in dry matter (DM) yield, while stubble turnip was the most stable. Both DM yields and in vitro digestibilities rose during the autumn, reaching a maximum in mid‐December for stubble turnip and forage rape, and in mid to late November for fodder radish. Yield and digestibility subsequently declined. The N concentrations of the forages exhibited a contrary trend, reaching minimum values at about the time of the highest DM yields. The gradual changes in crop quality suggest that the crops are well suited to grazing utilization, in which management is simplified if crop quality shows little variation.
The herbage intake and performance of set‐stocked suckler cows and calves
Authors: BAKER R. D. , LE DU Y. L. P. , ALVAREZ F. 
Published: April 2006

AbstractGroups of eight Hereford × Friesian cows and their South Devon cross calves were set stocked over a 24‐week grazing season at 3·23 (low), 3·21 (medium) or 4·24 (high) cows ha‐1 together with their calves. For the first 8 weeks only two‐thirds of the total area was grazed. Increasing the stocking rate from low to medium reduced daily milk yield and cow and calf liveweight gains by 1·2, 0·24 and 0·29 kg d‐1 respectively, and from medium to high by 1·2, 0·24 and 0·23 kg d‐1. The main sward factor influencing faecal output and herbage intake was the quantity of organic matter on the pastures but the digestibility of the herbage selected also exerted a significant effect on the intake of cows. Major depressions in the herbage intake of cows occurred once the average sward height fell below 7 cm. Output of calf live weight was 628, 658 and 743 kg ha‐1 for the 3 stocking rates from low to high, and for cows 246, 179 and 30 kg ha‐1. It was concluded that decisions on pasture management should be taken in relation to the cow rather than the calf on set‐stocked swards.
A comparison of indirect methods of estimating feed intake on pasture
Authors: WANYOIKE MARGARET M. , HOLMES W. 
Published: April 2006

AbstractThe data from 12 individual cattle grazed on a uniform sward were used to compare field sampling of faeces with three time‐schedules for rectal sampling of faeces. Estimates of digestibility from a faecal nitrogen equation were compared with estimates based on in vitro digestibility, or modified acid‐detergent fibre determinations, on clipped herbage samples.Field sampling gave a lower coefficient of variation (8%) in chromic oxide content than did grab sampling (14%). Grab sampling introduced an upward bias in estimates of faecal output compared with field samples. The estimate of digestibility based on the faecal index was intermediate to those based on clip samples from the upper and lower horizons of the sward. There was no difference in the mean digestibilities estimated from in vitro or MAD fibre.
Establishment, persistence and nitrogen fixation of white clover and marsh trefoil on blanket peat
Authors: LAIDLAW A. S. 
Published: April 2006

AbstractWhite clover (cv. S184 or Blanca) or marsh trefoil (cv. Grasslands 4703 or Grasslands Maku) were sown alone and in combination with a companion grass (tall fescue, red fescue, perennial ryegrass or ryegrass cleanings) on a peat area of hill land originally dominated by Juncus articulatus and Molinia caerulea.Lime and ground rock phosphate were applied in 1973, the area rotavated to a shallow depth and seeds sown in May 1974. No fertilizers were applied except at sowing time and two harvests were taken per annum for 4 years.Differences in yield and legume content between companion grass treatments were small. After the first full harvest year Blanca swards usually had the lowest DM yields and those containing Maku the highest. The contribution of marsh trefoil to total herbage yield increased from 4·2% in 1975 to 22% in 1978, whereas white clover decreased from 4·2 to 1·2%. Legume yields in 1978 were less than half those in 1977. Overall, N yields were low, Maku swards fixing most N estimated to be highest in 1977 at 35 kg ha‐1.It is concluded that marsh trefoil grows well on upland peat but more information on its response to grazing is necessary before conclusions can be drawn about its value in hill land improvement.
The digestibility of herbage selected by oesophageally fistulated cows, steer calves and wether sheep when strip‐grazing together
Authors: LE DU Y. L. P. , BAKER R. D. 
Published: April 2006

AbstractThe digestibility of herbage selected by dairy cows, milk‐fed calves, weaned calves and wether sheep was examined on four occasions each day as they strip‐grazed together a daily allocation of herbage. The average quality of the material selected by each group was similar. Organic matter digestibility of the herbage selected declined from 0·274 to 0·223 as the average height of the sward fell from 16 to 6 cm; this decline was slightly more rapid for the cows than for the other stock. A similar trend was also evident in samples cut from the sward to simulate the horizon removed prior to each sampling time.
Productivity of red clover grown alone and with companion grasses over a four‐year period
Authors: McBRATNEY J. M. 
Published: April 2006

AbstractSix red clover cultivars, three diploid—Essex, Sabtoron and Violetta—and three tetraploid— Teroba, Red Head and Hungaropoly—were sown alone and with each of three companion grasses—timothy (S48), tall fescue (S170) and perennial ryegrass (S24). The productivity and persistency of the red clover cultivars were compared over 4 years. Dry matter (DM) yield, DM digestibility and the crude protein (CP) concentration were assessed and botanical analyses conducted on herbage samples from each treatment at each of three harvests per annum. Annual fertilizer application consisted of 165 kg P and 312 kg K ha‐1.Comparing clover cultivars alone Essex was significantly less productive and less persistent than the other five cultivars. Yield and persistency of the five other cultivars did not differ markedly within years with the exception that the diploids were significantly less productive than the tetraploids in the fourth year. Over all 4 years mean annual total DM and clover DM yields of the five cultivars were between 12·2 and 13·2 t ha‐1 and between 9·2 (79·2% of total DM yield) and 10·2 (83·2%) t ha‐1 respectively, and differences were not significant.Up to the end of the third year there was little or no advantage gained by the inclusion of a companion grass, annual total DM yields being between 11·2 and 14·2 t ha‐1 for clover alone and between 10·2 and 14·2 t ha‐1 for clover‐grass mixtures. In the fourth year there was an overall tendency for the yield of the clover alone to be lower, between 7·2 and 12·2 t ha‐1, than that of the clover‐grass mixture, between 8·2 and 13·2 t ha‐1, and this was more pronounced with the diploid than with the tetraploid clover cultivars. Sown with companion grasses, Essex and Hungaropoly were lower in yield and in contribution than the other cultivars over the 4 years. The influence of the companion grass on total dry matter yield showed that the contribution of timothy was low relative to that made by tall fescue and perennial ryegrass. Perennial ryegrass made the most varied contribution from year to year. Tall fescue was the most consistent contributor with all clover cultivars and at the end of 4 years both yield and clover‐grass balance had not changed materially.No pronounced differences in DM digestibility were evident between treatments.Crude protein concentration of the pure clover was similar to that of the clover‐timothy treatments and both would appear to be superior to either the clover‐perennial ryegrass or clover‐tall fescue mixtures.It is considered that red clover dominant swards are suitable for use under a cutting regime and can provide high yields of DM at a low cost for up to 4 years. Such swards are self‐sufficient in N and in addition soil N accumulation can be exploited in the production of succeeding crops.
A comparison of a hybrid stubble turnip (cv. Appin) with other cruciferous catch crops for lamb fattening. 1. Initial evaluation for dry matter yield and forage quality
Authors: SHELDRICK R. D. , LAVENDER R. H. 
Published: April 2006

AbstractA novel hybrid stubble turnip, Appin, bred by the Scottish Plant Breeding Station (Brassica campestris ssp. rapifera cv. Tigra ×B. campestris ssp. nipposinica cv. Mizuna) was compared in small‐plot cutting trials with stubble turnip (B. campestris ssp. rapifera cv. Ponda), forage rape (B. napus ssp. biennis cv. Canard) and fodder radish (Raphinus sativus cv. Neris) for 3 years, 1975–77, samples being taken from October to December or January each year to cover the likely period of utilization by grazing lambs. Except for the first year, Appin proved to yield less DM than Ponda, and be inferior in digestibility and metabolizable energy (ME) content, though N contents were on occasion higher. Canard had the highest overall ME content. In dry conditions in autumn 1977, Ponda proved the more reliable crop, suffering less depression in yield than other species. Anti‐metabolite contents were determined in freeze‐dried samples taken in winter 1976‐77 and showed Canard to have the most brassica anaemia factor (S‐methyl cysteine sulphoxide): contents of thiocyanate were generally similar between crops.As the degree of utilization of such forages when grazed can outweigh differences in recorded above‐ground DM yields from cutting trials, it was considered that claims of better root anchorage and hence better utilization for Appin warranted evaluation in a grazing trial.
Sward growth under cutting and continuous stocking managements: sward canopy structure, tiller density and leaf turnover
Authors: JONES M. B. , COLLETT B. , BROWN SIAN 
Published: April 2006

AbstractThe change in structure of continuously grazed versus infrequently cut swards of perennial ryegrass (Lolium perenne L), cv. S23, was investigated during their first full harvest year. Measurements were made from early May until late September. The intensity of stocking by sheep in the grazed sward was adjusted in an attempt to maintain a high level of radiation interception and the cut sward was harvested at approximately monthly intervals.The herbage mass, lamina area index and radiation interception of the cut sward varied in a cyclic pattern between harvests but in the grazed sward these parameters showed considerably less variation, although they all increased early in the season and then declined later. The proportion of dead material above ground increased throughout the season in both sward types but was more marked in the grazed sward.There were major differences between the grazed and cut swards in the number of tillers per unit ground area; the difference became more marked throughout the season and by September the tiller densities in the grazed and cut swards were 3·204 m‐2 and 6·203 m‐2 respectively. Divergence in tiller density was associated with differences in specific stem weight and leaf area per tiller.Rates of appearance and death of leaves on tillers in the grazed sward were determined. During May, leaf appearance exceeded leaf death but this was reversed in June. During the rest of the season as a new leaf appeared on a tiller so the oldest leaf died.
Slot‐seeding investigations. 2. Time of sowing, seed rate and row spacing of Italian ryegrass
Authors: HAGGAR R. J. , SQUIRES N. R. W. 
Published: April 2006

AbstractItalian ryegrass was slot‐seeded into permanent grass in two field experiments at Oxford. In the first experiment August and September proved to be the most reliable months for slot‐seeding, with April as a possible alternative. A row‐spacing experiment showed that the optimum distance between rows was about 30 cm; seed rate in the row had a lesser influence on increasing herbage growth. In both experiments slot‐seeding did not result in any substantial change in earliness of growth or alter total herbage harvested but it did even out the seasonal distribution of growth, particularly by increasing it in the following July.
Evaluation of propionic acid‐treated hay as a feed for growing sheep
Authors: DAVIES M. H. , WARBOYS I. B. 
Published: April 2006

AbstractTwo experiments were carried out to evaluate propionic acid‐treated hay as a feed for sheep in which eighteen ewes (experiment 1) and eighteen ewe lambs (experiment 2) were fed ad libitum on hay only. At feeding, the propionic acid‐treated hays had higher D‐values and water‐soluble carbohydrate concentrations, but a lower dry matter concentration, than the untreated hays. The voluntary feed intake and liveweight gain of the sheep fed on two acid‐treated hays and on an untreated hay in experiment 1 were similar. In the second experiment an acid‐treated moist hay was eaten in greater amounts by the sheep and liveweight gains were greater than on the corresponding untreated hay, but were not significantly different from those of sheep fed on field‐cured hay.