bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photoperiodic control of breeding activity in the Southdown ewe with particular reference to the effects of an equatorial light regime
Authors: Thwaites C. J. 
Published: March 2009

1. Oestrous activity was studied in three groups of eight Southdown ewes exposed respectively to natural lighting (30½° S.), accentuated reversed seasonal lighting, and equatorial lighting for a period of 2 years.2. Control ewes exhibited a restricted breeding season confined to the autumn and winter months of each year. The breeding season averaged 102–5 days in length and during it the ewes experienced an average of 7·14 ± 0·47 oestrous periods.3. The natural breeding season was almost completely reversed by artificial reversal of the normal seasonal variation in daylength. This constitutes presumptive evidence that daylength is the major factor controlling seasonality of oestrus in Southdown ewes.
Change of skeletal dimensions during growth in sheep: the effect of nutrition
Authors: Searle T. W. , Graham N. McC. , Donnelly J. B. 
Published: March 2009

SummaryMeasurements of skeletal size were made at 2–3-month intervals on 30 Border Leicester × Merino castrate male (wether) sheep between 2 and 27 months of age. Fifteen sheep were fed ad libitum on a high-quality diet and the other 15 half the average amount consumed by the first group, age for age. The ad libitum group grew faster and were larger in all body dimensions on each occasion, except for leg length at 27 months which showed no statistical difference between groups. When the groups were compared over the live-weight range common to both (16–44 kg) the unrationed animals were consistently wider at the shoulders but smaller in leg and chest dimensions.The relationship between each body component and age is described by a Mitscherlich equation and the relationship with live weight by a linear equation in which both variables are log transformed. Separate relationships were determined for each sheep and tested for differences within and between groups.
Genotypic and phenotypic variances and correlations in field beans (Vicia fabaL.)
Authors: Yassin T. E. 
Published: March 2009

SUMMARYEstimates of genotypic and phenotypic variances and covariances were determined for yield and yield components in ten field beans varieties grown at two locations over three seasons.Substantial amounts of genotypic variance were obtained for yield/plot, 1000-seed weight and number of pods/plant. Variability in number of seeds/pod and much of the variation in yield/plant was attributable to environmental effects and their interaction with the varieties. Seed yield/plot was closely and positively correlated with number of pods/plant and yield/plant, while it was closely and negatively correlated with 1000-seed weight.The implications of these correlations for selection are discussed.
Sources of magnesium for grassland
Authors: McIntosh S. , Crooks P. , Simpson K. 
Published: March 2009

SUMMARYIn a 3-year field experiment, calcined magnesite, Epsom salt, magnesium ammonium phosphate and magnesian limestone gave only small and non-significant increases in yield of a mixed sward but increased the concentration of magnesium in the herbage at all 11 cuts. Magnesianlimestone increased plant magnesium concentrations less than calcined magnesite, magnesium ammonium phosphate or Epsom salt, all of which had a similar effect; each increment of calcined magnesite gave additional increases in magnesium concentration.Concentration of magnesium in the plant dry matter increased as each season progressed and was linearly related to exchangeable magnesium. At an exchangeable soil magnesium of 1·4 m-equiv./100g soil, Mg concentrations doubled between the first and last cuts. Changes in magnesium concentrations caused by increasing the exchangeable soil magnesium from 0·7 to 1·4 m-equiv./100g soil were less than the seasonal effects.
Effect of dense, stratified sandy soil on crop roots
Authors: Worker G. F. , Ayers R. S. , Karah M. A. , Thomason R. E. 
Published: March 2009

SUMMARYA study was conducted to determine root development in a stratified and mixed sandy soil in the Sahara sands of Libya. Lucerne (Medicaqo sativa L.), millet (Pennisetum typhoides Burn.)> wheat (Triticum activumL.), grain sorghum (Sorghum bicolor L.), and several other crops were grown on soil that varied in depth to the stratified layers. Root depth and growth were measured by excavating along a representative root at intervals until the crop was mature or until no further root penetration into the subsoil occurred.Trial plantings showed that none of the root systems of the plants tested could penetrate the stratified layers to any important extent, even with the application of adequate water and fertilizer, although all the layers were sufficiently porous to allow surplus water to drain through them freely. However, a few roots of lucerne, sudangrass, grain sorghum, and millet penetrated 2—3 cm into these layers, and many roots, especially of lucerne, grew into any natural cracks that occurred in these layers. If the compacted layer was loosened by cultivation, all the crops tested rooted normally in the loosened zone.
Metabolic and endocrine responses of pregnant and lactating ewes to intravenous glucose or insulin
Authors: Bassett J. M. 
Published: March 2009

SUMMARYTo investigate whether late pregnancy results in increased resistance to insulin action in ewes, a group of 18 crossbred ewes (six with twin foetuses) were given intravenous injections of glucose (0·25 g/kg) and insulin (0·25 U/kg) about 18days before full term and again during lactation, about 36 days after delivery. Before the injections, basal plasma concentrations of glucose, free fatty acids and growth hormone were lower during pregnancy than during lactation, but insulin concentrations were similar on the two occasions and cortisol concentrations were higher during pregnancy.Rates of glucose removal and insulin secretory responses to the glucose injection were similar on the two occasions, both in ewes with single lambs and in those with twins. Insulin injection also resulted in similar decreases in glucose concentration on the two occasions in all ewes. Recovery from hypoglycaemia was somewhat delayed during pregnancy whencompared with lactation, but less so than in wether sheep given a similar injection of insulin. The plasma free fatty acid concentration decreased more slowly after glucose injection during pregnancy than in lactation. Responses of plasma cortisol concentration toinsulin-induced hypoglycaemia were similar on the 2 days, but plasma growth hormone concentration increased far more in lactating ewes after both injections.The results did not indicate increased antagonism to insulin action in ewes during late pregnancy, but did show that changes in the counter-regulatory hormones after the disturbances to glucose homeostasis may differ markedly in the two situations and suggest that hyper-responsiveness of the system regulating growth hormone secretion contributes to the increased plasma growth hormone concentration observed in lactating animals.
Concentrations of blood constituents from 12 to 72 weeks of age in genetically high and low milk production lines of Friesian and Jersey cattle
Authors: Gibson J. P. , Wiener G. , Field A. C. 
Published: March 2009

SummaryBlood samples were collected at 12-week intervals from 12 to 72 weeks from a total of 221 growing Friesian and Jersey calves and assayed for plasma concentrations of free fatty acids (FFA), ketones, glucose, calcium, phosphorus, magnesium, copper, albumin and globulin. Sixty-six of the animals could be allocated to genetically high and 73 to genetically low milk producing lines on the basis of being sired by the ‘best’ or ‘worst’ nationally available progeny tested sires. All animals were housed indoors and fed a complete pelleted diet ad libitum. There were no differences between genetically high and low milk production lines for any blood constituent and no useful indicators of genetic merit for milk production in later life. There were no differences between breeds for metabolites related to energy status (FFA, ketones, glucose). Friesians bad higher magnesium and lower mean copper concentrations than Jerseys and had higher phosphorus concentrations up to 36 weeks. Differences between breeds and ages in mineral concentrations were not related to breed differences in the discrepancy between observed intakes and predicted requirements of minerals. Concentrations of globulins were higher and of albumin lower in Jerseys than in Friesians at 12 and 24 weeks possibly owing to slightly higher disease incidence of Jerseys in early life. There were changes with age in concentrations of all constituents except FFA. There was evidence of genetic variation within breeds and lines for mean plasma concentrations of ketones, copper and globulin. There was no evidence for differences between females and castrates for any blood constituent.
Dispersal of Pyrenopeziza brassicae spores from an oil-seed rape crop
Authors: McCartney H. A. , Lacey M. E. , Rawlinson C. J. 
Published: March 2009

SummarySpores of Pyrenopeziza brassicae, which are mostly dispersed by rain splash, were trapped 4 m above and 20 m downwind of an oil-seed rape crop. This suggests that not all trapped spores were transported in ballistic splash droplets (100–2000 μm); indeed some were airborne during periods of dry weather following closely after rain. Vertical and horizontal spore concentration gradients corresponded to the gradients expected for spores with fall speeds of between 2 and 5 cm/sec. Atmospheric dispersal calculations suggest that such spores have the potential for transport over considerable distances to other susceptible crops.
Effect of cultivar, carbofuran and row spacing on the incidence of stem and leaf nematodes (Ditylenchus dipsaci and Aphelenchoides ritzema-bosi) in lucerne (Medicago sativa) and on lucerne herbage yield
Authors: Whitehead A. G. 
Published: March 2009

SUMMARYIn a clay loam at Rothamsted, inoculated with lucerne stem nematode (Ditylenchus dipsaci) and a leaf nematode (Aphelenchoides ritzema-bosi), lucerne herbage yields were increased on average by 17 and 59% respectively, in the first and second years of a 4-year experiment (1988–91), by carbofuran granules applied around the seeds at sowing in spring 1988. In seven-row plots over the 4 years of the experiment, 1·65 kg a.i./ha increased total yield as much as did 3·3 kg a.i./ha (11 and 12%, respectively). In four-row plots over the same period, 1·9 kg a.i./ha increased total yield by 9%. The cultivars Euver and Vertus, which are partially resistant to D. dipsaci, yielded 44·3 and 48·5 t dry matter/ha, respectively, whereas Europe and Vela, which are susceptible to the nematode, yielded less (36·3 and 28·6 t/ha, respectively). When sown in summer 1990 in four-row plots, cultivars Europe and Euver yielded larger crops in 1991 in plots given 1·2 or 2·3 kg a.i. carbofuran/ha in 1990 (on average 34 and 48%, respectively) than in untreated plots. As little as 0·6 kg carbofuran/ha increased the yield of cv. Europe in infested soil.The stunting of lucerne plants, associated with D. dipsaci infestation, was greatly decreased by carbofuran, which prevented infestation of the first crop by D. dipsaci and A. ritzema-bosi. Stem nematode infestation of lucerne plots was adequately and quickly assessed by measuring the lengths of rows stunted by D. dipsaci. Other methods of assessment were laborious and no more reliable.
Use of para-amino hippuric acid to measure blood flows through portal-drained-viscera, liver and hindquarters in sheep
Authors: Ortigues I. , Durand D. , Lefaivre J. 
Published: March 2009

SUMMARYThe objectives of this study were (i) to evaluate a new surgical procedure to catheterize hepatic vessels as well as the posterior aorta and vena cava, (ii) to test a modification of a downstream dilution technique in order to measure blood flows through splanchnic tissues and hindquarters in rapid succession, and (iii) to improve the reliability of splanchnic blood flow measurements using paraamino hippuric acid (PAH). Ten adult ewes were used. The transhepatic surgical approach used proved successful; it was relatively easy to set up and a good recovery of hepatic functions was obtained. The attempt to measure splanchnic and hindquarters blood flow in rapid succession by alternating the sites of PAH infusion was unsuccessful, probably because of transient modifications in infusion rates due to different blood pressures in veins and arteries. Indeed, arterial PAH concentrations changed with infusion site. Finally, a better reproducibility of splanchnic blood flow measurements was obtained in sheep, fed every 3 h, by infusing the required amount of PAH partly via the mesenteric vein and partly via a ruminal vein.
Attainment of puberty and reproductive performance in Clun Forest ewe lambs
Authors: Dýrmundsson Ó. R. , Lees J. L. 
Published: March 2009

SUMMARYCertain aspects of puberal development and reproductive performance in Clun Forest ewe lambs with a wide range of birth dates were investigated during the two seasons 1969–71. Of 33 ewe lambs born in the spring of 1969, 26 exhibited their first oestrus at a mean date of 8 November 1969 ± 2·5 days, the mean age being 228·3 ± 2·4 days and the mean body weight 36·3 ± 0·9 kg. The lambs which failed to breed in their first year, together with lambs born in the autumn of 1969, attained puberty during the autumn of 1970. Twenty-three ewe lambs carried foetuses to term in the spring of 1970 and had a mean lambing rate of 113·0 ± 7%. Of 84 ewe lambs born in the spring of 1970, 73 attained puberty in the first year of life at a mean date of 11 November 1970 ± 2·7 days, the mean age being 223·7 ± 3·0 days and the mean body weight 32·2 ± 0·5 kg. Cyclic activity of ewe lambs born in 1970 was recorded throughout their first breeding season. They experienced their last oestrus of the season at a mean date of 24 January 1971 ± 2·2 days, the mean age being 296·9 ±3·9 days and the mean body weight 32·4 ± 0·6 kg. The mid-breeding season was 18 December 1970, coinciding with the shortest days, and the mean number of heats exhibited throughout the season was 5·15 ± 0·24 per lamb.Marked individual variation existed in age and body weight at puberty and in breeding activity, largely due to differences in date of birth and growth rate during rearing. Ewe lambs born early tended to experience their first oestrus earlier in the season than late born lambs but they did so at a higher age and heavier body weight. Fast growth rate and earliness of puberty were associated with extended duration and enhanced regularity of cyclic activity. Time of birth was clearly of fundamental importance in relation to the onset and duration of breeding activity in the ewe lambs included in the present study.Adult rams of three breeds were found to vary consistently in the proportion of ewe lambs which they detected in oestrus, rams of the lambs' own breed being most efficient.
Errors associated with expressing pasture intake as dry rather than organic matter at high stocking intensities
Authors: O'Donovan P. B. 
Published: March 2009

SUMMARYFollowing both a low and high plane of winter feeding two groups of 18 bullocks each were stocked at 2·5 (low), 4·3 (medium) and 6·2 (high) bullocks per hectare. The Hereford × Shorthorn bullocks averaging 350 kg live weight were rotationally grazed on ten plots, seven of which contained a H.I. white clover mixture and the remaining three contained permanent pasture. Pasture digestibility and intake were determined for 16 weekly periods between early April and late September. In vitro digestibility was determined on samples obtained by means of two rumen-fistulated bullocks. A gelatin capsule containing 10 g of chromic oxide was administered daily to each bullock to estimate faecal output. Digestibility, faecal output and intake were expressed on both a dry and organic-matter basis. Increasing the stocking rate resulted in a corresponding decrease in organic matter (OM) percentage of the faeces but the magnitude of the differences varied throughout the growing season. The average decline (all 16 periods) was linear, the OM percentage of faeces being 80·9, 76·8 and 72·6 for low, medium and high stocking rates, respectively. Faecal ash content of rectal samples and those taken from the pasture differed significantly only in a few instances, indicating that pasture faecal contamination may not be serious if careful sampling is practised. Higher ash intakes at high stocking intensities are reflected in herbage intake errors when results are expressed as dry matter instead of organic matter.
An experiment begun in 1958 measuring effects of N, P and K fertilizers on yield and N, P and K contents of grass:2. Residual effects on arable crops, 1968–76
Authors: Penny A. , Widdowson F. V. 
Published: March 2009

SUMMARYAn experiment at Rothamsted during 1958–67 measured effects on yield, on K uptake and on soil K of applying all combinations of 38, 75 and 113 kg N and 0, 31 and 62 kg K/ha per cut to grass leys, which were cut and removed. Soil K was depleted most where most N and least K were given. Annual applications of 0, 33 and 66 kg P/ha were also tested; soil P was not depleted. The grass was then ploughed.In 1968, residual effects were measured by spring wheat. In 1969 and in 1970 104 kg/ha of fresh K was applied on half of each plot; potatoes (1969) and spring wheat (1970) valued residual and fresh effects of K.In 1971 potatoes tested 0, 104 and 208 kg/ha of fresh K, cumulatively with the three amounts given to the grass and also extra K (104 kg/ha) on half-plots, cumulatively with that given in 1969 and 1970. In 1972 winter wheat, and in 1974 and 1975 spring barley, measured residues of all treatments previously applied (the site was fallowed in 1973).Finally, in 1976, potatoes tested 0, 156 and 312 kg/ha of fresh K on whole plots, cumulatively with the previous dressings of K, and also 156 kg/ha of extra K on half-plots, again cumulatively. All these test crops were given basal N.Yields and K contents of wheat at ear emergence and yields of wheat grain were largest after grass given 38 kg N and 62 kg K/ha per cut, because here soil K depletion was least. Wheat grain yields benefited consistently from fresh K. K content of the wheat at ear emergence was a good indicator of the need for K, but K content of grain was not, because it was unaltered by K fertilizer. Barley was a poor test crop for K, because yields of grain were little affected by previous treatments.Percentage K in potato leaves (in July in 1969 and 1971, in August in 1976) and yield of tubers were well correlated. Largest yields in 1969, 1971 and 1976 came where the leaves contained 3·43, 3·76 and 2·82% K, respectively, i.e. from soil containing most exchangeable K, plus most fresh K. There was no indication that maximum yields had been obtained, so the largest amounts (kg/ha) of fresh K tested (104 in 1969, 312 in 1971 and 468 in 1976) were insufficient to counteract depletion of soil K by the grass. Because the grass did not deplete soil P, the test crops benefited only little from either residual or fresh P.
Environmental effects on seed oil percentage and fatty acid composition in white lupin (Lupinus albus)
Authors: Williams Watkin , McGibbon R. 
Published: March 2009

SUMMARYThe effects of temperature, light intensity and nitrogen supply on the amount and fatty acid composition of the seed oil in Lupinus albus has been investigated. The percentage seed oil was reduced and its degree of saturation increased at higher temperatures. High temperatures during the dark period caused a reduction in percentage oil only when combined with day temperature of 20 °C, indicating a highly specific interaction between day and night temperatures. Shading reduced oil content, an effect which may determine response to population density and the optimal phenotype for high-oil cultivars.
Microvolt T-wave alternans and the selective use of implantable cardioverter defibrillators for primary prevention: A cost-effectiveness study
Authors: Filion Kristian B. , Xie Xuanqian , van der Avoort Charlotte J. , Dendukuri Nandini , Brophy James M. 
Published: March 2009

Objectives:Implantable cardioverter defibrillators (ICDs) are an effective but expensive treatment for the prevention of sudden cardiac deaths in patients with severe left-ventricular dysfunction. Recent studies suggest that microvolt T-wave alternans (MTWA) predicts mortality and severe arrhythmic events in this population. However, the impact of MTWA on ICD cost-effectiveness is unknown.Methods:A Markov decision-analysis model evaluated three treatment strategies for primary prevention in patients with severe left-ventricular dysfunction: (i) medical therapy for all; (ii) ICD therapy for all; and (iii) selective ICD therapy based on non-negative (positive or indeterminate) MTWA test results. Incremental cost-effectiveness ratios (ICER) were calculated from the perspective of a third party payer using a 10-year time horizon. Sensitivity analyses examined the robustness of the estimates.Results:A treatment strategy involving ICD therapy in all patients was associated with an ICER of $121,800/quality-adjusted life-year (QALY) compared with medical therapy, whereas a treatment strategy involving the selective use of ICDs based on MTWA test results was associated with an ICER of $108,900/QALY compared with medical therapy. Sensitivity analyses suggest that, under most scenarios, the selective use of ICDs based on MTWA results does not decrease the ICER to below $100,000/QALY.Conclusion:MTWA only marginally improves the cost-effectiveness of ICDs for primary prevention in patients with severe left-ventricular dysfunction. There remains a need for improved means to effectively identify which patients will derive the greatest benefit from ICD implantation.
Modeling the cost-effectiveness of treatment of rheumatoid arthritis with rituximab using registry data from Southern Sweden
Authors: Lindgren Peter , Geborek Pierre , Kobelt Gisela 
Published: March 2009

Objectives:The aim of this study was to estimate the cost-effectiveness of rituximab in patients not responding adequately to the first tumor necrosis factor (TNF) inhibitor using a model constructed to predict resource consumption and health outcomes in a population-based registry of biological treatments in Southern Sweden (SSATG).Methods:The model was developed as a discrete event simulation model, using SSATG data for the years 1999–2007. The data set included 1,903 patients with complete data on treatments (up to three treatment lines), functional capacity (HAQ), disease activity (DAS28), and utility (EQ-5D). Resource consumption was based on a regular population-based survey of patients in Southern Sweden. Rituximab was incorporated as second line treatment, using effectiveness data for the active group (N= 311) in a clinical trial comparing rituximab to placebo (REFLEX). It is thus compared to the mix of second line biologics used in SSATG. The analysis starts after failure of the first TNF inhibitor. Results are reported as costs (€2008) per quality-adjusted life-year (QALY; both discounted 3 percent), for the societal perspective in Sweden.Results:Total costs in the rituximab strategy are estimated at €401,100 compared with €403,000 in the TNF-inhibitor arm. Total QALYs are 5.98 and 5.78, respectively. The findings were found to be robust in extensive sensitivity analysis.Conclusions:In our model, a strategy where rituximab is used as second line treatment after failure of the first TNF inhibitor provides a small saving (essentially due to the lower price of rituximab) and a QALY gain (due to better effect than the mix of second line TNF inhibitors).