bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some causes of yield variation in an intensive spring barley experiment at Woburn, 1972–8
Authors: Hornby D. , Henden D. R. , Catt J. A. 
Published: March 2009

SUMMARYAn experiment with two blocks containing phased sequences of continuous spring barley after beans or fallow was located on sandy soil over Lower Greensand on a gentle north to south (N–S) slope at Woburn Farm. Season had the greatest effect on yield with a 135% difference between the worst (1975, 1·73 t/ha) and the best (1974, 4·06 t/ha). years. N–S position was the next most important factor with average differences of 65 and 52% between the plots at the top and bottom of the site in blocks I and II respectively. The third most important factor was E–W position which gave a maximum difference of 35% in 1975.A fertility trend with a strong linear component, which was most conspicuous in drier years, followed the main slope of the experiment and was attributed to erosion (fieldwash). After 1972 as different cropping sequences were progressively introduced, yield variation due to crop sequence differences was confounded with this positional effect.Crops in the eastern block were taller by l·5–12·3% and, after adjustment for the linear trend, yield was on average 15·6% greater than in the western block. The site is astride a N–S soil boundary with Stackyard series to the east and Cottenham series to the west. The Stackyard soil has a greater available water capacity, and is subject to drought less frequently than the Cottenham soil. Using Penman's (1971) data for the Cottenham series at Woburn and estimates of profile available water for the two series elsewhere on the farm, theoretical yields were derived, which were generally greater than actual yields adjusted for the N–S linear trend (block means 1·47–4·32 t/ha), but which showed similar trends in the between-block differences. Explanations for discrepancies between theoretical and actual yields are discussed. The incidence and severity of take-all disease and differences in soil pH were always small and unlikely to have caused significant yield variations.
Variability of wheat yields in England and Wales
Authors: Church B. M. , Austin R. B. 
Published: March 2009

SUMMARYInformation is assembled on how much wheat yields vary from place to place, from year to year and between years in England and Wales. Some indication of the practical importance of this variation is given by comparisons with the yield differences caused by individual management decisions as measured in comparative experiments, and with plot-to-plot variation in such experiments.
The effect of plane of nutrition on the growth and development of the East African dwarf goat. Part II. Age changes in the carcass composition of female kids
Authors: Wilson P. N. 
Published: March 2009

1. The age changes in carcass composition of female kids killed at birth, 9, 16, 25 and 30 lb. are described.2. The organs and tissues of the kids were weighed both wet and oven-dried, allowing the dry-matter percentages at different stages of growth to be calculated. The total dry-matter percentage for day-old kids averaged 26·5%, rising to a maximum of 40·5% at the 25 lb. stage. The greatest increase in dry-matter percentage was between birth and the 9 lb. stage, which was reached at approximately 1 month. This increase in dry matter is chiefly due to a steady rise in the dry-matter content of the muscular and skeletal tissues; from 20·2 to 25·4%, and from 34·3 to 59·6%, respectively, between birth and maturity.3. The various joints of the kid were weighed and recorded separately, and the changes in the proportions of the joints illustrated centripetal growth. At birth, the joints were present in the following proportions: thorax 30%; legs 40%; head 20%; pelvis 10%. As the kid developed, there was a marked increase in the proportion of thorax and pelvis, accompanied by a corresponding decrease in the proportion of the head and foreleg.
Denitrification in soil. I. Methods of investigation
Authors: Bremner J. M. , Shaw K. 
Published: March 2009

1. Methods of investigating denitrification in soil are critically discussed with special reference to methods based on total-N analysis.2. A modified Kjeldahl method of determining nitrogen which includes nitrate and nitrite and is applicable to waterlogged soil is described and the use of this method in studies on denitrification in soil is illustrated and discussed.3. It is shown that rapid denitrification of nitrate in soil can be induced by incubating the soil under waterlogged conditions with organic materials such as glucose and that denitrification can be followed by total-N analyses if the organic material used to induce denitrification is not added in such excess that it also promotes significant fixation of atmospheric nitrogen.4. The percentage of added nitrate-N lost by denitrification on incubation of waterlogged soils with different amounts of nitrate and sufficient glucose for denitrification was found to be the same whatever the level of application of nitrate.5. Denitrification of nitrate in waterlogged soil containing glucose was found to be accompanied by a rapid but temporary accumulation of large quantities of nitrite and by the formation of smaller amounts of ammonia. Hydroxylamine could not be detected during denitrification, but it was found that this compound was rapidly decomposed in the soils examined by a process which appeared to be purely chemical.6. It is shown that denitrification of nitrate in soil is a microbiological process and that the viability of the micro-organisms responsible for denitrification is not affected by air-drying and storage of the soil.
Comparisons between placing and broadcasting of nitrogen, phosphorus and potassium fertilizers for potatoes, peas, beans, kale and maize
Authors: Widdowson F. V. , Cooke G. W. 
Published: March 2009

1. In eight experiments on main-crop potatoes in 1953–4 placing 0·5 cwt. N/acre in a band beside the seed tended to give higher yields than broadcasting the dressing; when 1·0 cwt. N/acre was applied, broadcasting tended to be superior to placement. There were no consistent gains from placing 1·5 cwt. K2O/acre.2. Four other potato experiments in 1954–6 tested all combinations of placing and broadcasting two levels of nitrogen and potassium. There was no clear relationship between the effects of broadcasting or placing one nutrient and the way in which the other nutrient was applied. When 0·5 cwt. N was applied, placing gave higher yields in seven out of ten possible comparisons (one effect was significant). With 1·0 cwt. N/acre there were also seven of ten comparisons in favour of placement (three significant effects), but in two other comparisons broadcasting gave significantly higher yields. Placing potassium gave higher yields than broadcasting in sixteen out of twenty comparisons (six significant effects), in one of the remaining comparisons broadcasting potassium was significantly superior. Placing of the potassium and, to a lesser extent, the nitrogen components of a complete potato fertilizer is likely to be beneficial.3. In two experiments each on green peas and broad beans placing of phosphorus and potassium separately and together gave consistently higher yields than broadcasting these nutrients. When nitrogen was used in addition to phosphorus and potassium there were small gains in yield of broad beans provided the mixture was placed. There were no gains in yields of green peas from nitrogen however the mixture was applied.
Foetal dwarfism in sheep—an effect of high atmospheric temperature during gestation
Authors: Yeates N. T. M. 
Published: March 2009

The course of pregnancy was followed in three groups of Peppin-strain Merino ewes. Group 1 of seven ewes, maintained on a high plane of nutrition, all lambed; the mean birth weight of lambs was 8 lb. 6 oz. The six ewes in group 2, kept on a low plane of nutrition, all lambed; the mean birth weight of their lambs was 1 lb. 9 oz. lower (P<0·01). The seven ewes in group 3 kept on a low plane of nutrition and subjected daily to temperatures of 112° F. dry bulb, 92° F. wet bulb, produced only four lambs; the mean birth weight was 4 lb. 6 oz. less than those from group 1, and 2 lb. 13 oz. less than those from group 2 (P < 0·001).Scale photographs of the lambs, and X-rays and measurements of their long bones, after dissection, showed that the lambs of group 3 were miniatures: their skeletons were much reduced in size, whereas low nutrition alone (group 2), caused little skeletal reduction.The mechanism of dwarfing is not clear. However, fore-cannon bone lengths and liver weights, considered in relation to lamb birth weights indicated that it was not a nutritional effect.This study was undertaken at the Physiology Department, University of Queensland. It is a pleasure to thank Prof. W. V. Macfarlane for the valuable facilities, and for his help and encouragement.
Studies in the environmental physiology of cattle in Northern Rhodesia. I. The relation between the changes in the haemoglobin index with age and the development of the heat toleration coefficient
Authors: Walker C. A. 
Published: March 2009

An investigation has been made on the changes in the haemoglobin index with age in four breeds of indigenous African and two breeds of European cattle.1. Support is given to previous findings that the haemoglobin index was high and variable at birth and fell to an individual more stable adult level at between 2 and 3 years of age.2. The haemoglobin levels for mature animals of the four tropical breeds are higher than mean figures quoted for other tropical cattle, but still fall within the ranges quoted.3. The haemoglobin levels for the Friesian agreed with those quoted from temperate regions, but those for the Jersey were higher, agreeing most nearly with Jamaican figures. A reason for this is advanced.4. The haemoglobin levels of the tropical breeds were significantly higher than those of the two temperate breeds examined.5. Confirmation was given to the association of a high haemoglobin index with a high heat toleration coefficient.
The effect of sustained lactation on intake of solid food and growth rate of lambs
Authors: Doney J. M. , Peart J. N. 
Published: March 2009

SummaryAn experiment was designed to investigate the effect of a sustained lactation pattern on the intake of milk or solid food by lambs and on their consequent growth rate. Normal lactation pattern was compared with sustained lactation, achieved by fostering lambs at 24 days of age on to newly-lambed nurse ewes. Two genotypes of lamb were used; these were pure-bred Scottish Blackface and Textel × Blackface. Lambs were offered one of two qualities of pelleted concentrate food from 4 weeks of age.Maximum daily intakes of milk were 2·16 and 1·87 kg/day, respectively, for fostered and non-fostered lambs. This differential was maintained until the 10th week. Pattern of lactation had no significant effect on total energy intake from milk and solid food combined or on live-weight gain up to 10 weeks of age. Texel cross lambs consumed more food than did pure Blackface lambs and showed correspondingly higher rates of live-weight gain. Lambs ate slightly more of the higher quality pellets than the lower but there was no effect of solid food quality on milk intake. Within breed of lamb there was a negative relationship between intake of milk and of solid food.
Delaying ripening in harvested Nigerian green plantains
Authors: Ndubizu T. O. C. 
Published: March 2009

SummaryMature green plantains (Bini variety) dipped in fungicide and stored with Purafil in polyethylene bags, remained green and hard for 3–4 weeks before ripening started. Fruits stored with Purafil or potassium permanganate kept longer (by 2 weeks) than those stored with potassium iodate or potassium dichromate. Severe chemical and fungal damage occurred in fruits stored with calcium hypochlorite, indicating that plantain fruits may be sensitive to chlorine. No significant difference in storage life was observed between fruits stored in polyethylene bags alone and those stored in potassium iodate or potassium dichromate. There was much lower incidence of fungal infection in fruits dipped in thiabendazole (1 g/l) than those dipped in Diathane M45 (3 g/1). Fruits dipped in thiabendazole before storage remained virtually free of fungal attack even after they had completely ripened.
The effect of disposing high rates of copper-rich pig slurry on grassland on the health of grazing sheep
Authors: Gracey H. I. , Stewart T. A. , Woodside J. D. , Thompson R. H. 
Published: March 2009

SummaryOver a 3-year period 900 m3/ha of copper-rich pig slurry were spread during the growing season on a 0·6 ha permanent grassland sward and the grass continually grazed off each season with the same sheep. A total of 47 kg Cu/ha were applied to the area and this increased the EDTA-extractable copper in the topsoil. Herbage copper concentrations clearly showed that sheep grazing the area were continually exposed to high concentrations, and that most of the copper was present as surface contamination. Large quantities of copper were excreted in the sheep faeces indicating that copper passed through the animal.Monthly blood samples from the sheep showed that the enzyme glutamic-oxaloacetic transaminase (GOT) concentrations were slightly higher than those in sheep grazing an area which received no copper over the same period. By the end of the second season (October 1971) over 2000 i.u. GOT/1 were recorded in some sheep grazing the slurry treated area indicating severe liver breakdown at that time. However, during the winter when the sheep were inwintered, serum GOT concentrations decreased considerably. In the final grazing season a 0·2 ha area received monthly applications of copper sulphate instead of slurry. All sheep were slaughtered in November 1972 for post-mortem examination. There was little difference in the copper concentrations in the liver and kidneys of the sheep grazing the control and the slurry areas, although the sheep which grazed the copper sulphate area in the final season had higher concentrations.As no sheep died from chronic copper poisoning during the course of the investigation there would appear to be little or no danger to the health of sheep from grazing land which is receiving pig slurry at rates which supply less than 16 kg Cu/ha/year.
Sodium and Potassium Fertilizer in Relation to Soil Physical Properties and sugar-beet yield
Authors: Draycott A. P. , Durrant M. J. , Davies D. B. , Vaidyanathan L. V. 
Published: March 2009

SummaryDespite much experimental evidence showing that sodium fertilizer increases sugar–beet yield and decreases need for potassium, there is resistance to its use on some soil types through fears of deterioration in soil structure. Twelve field experiments with sugar beet were made in Eastern England, testing all combinations of autumn and spring applications of 0, 150 and 300 kg Na/ha and 0, 83 and 333 kg K/ha. Fields were chosen with soils of loamy very fine sand, very fine sandy loam, sandy clay loam and clay loam textures. Micro–plot and controlled environment studies were also made with the same soils to examine effects of sodium on seedling emergence and growth.Visual assessments of soil physical state following sodium application revealed no effect in the year sugar beet was grown nor in the following spring when cereals were grown. Measurements of physical properties of soils treated with sodium suggested that applications of several times the recommended amounts of sodium fertilizer would not damage soil structure. However, sodium fertilizer increased the osmotic suction of soil solution which, under some circumstances, e.g. dry springs or giving the fertilizer close to the time of sowing, decreased germination and seedling growth. For this reason and not because it has a detrimental effect on soil physical condition, sodium fertilizer best given in the autumn or some weeks before sowing.
Fat deposition in Hereford and Friesian steers: 1. Body composition and partitioning of fat between depots
Authors: Truscott T. G. , Wood J. D. , MacFie H. J. H. 
Published: March 2009

SUMMARYIn this paper, the first of a series of three in which fat deposition is examined in 42 castrate male Hereford and Friesian cattle, details are given on the experimental material and procedures used in all papers. Whole body composition (anatomical and chemical) and the partitioning of fat within the body are also reported in this paper.Four, two and 15 animals were slaughtered at 6, 13 and 20 months of age, respectively, afterad libitumfeeding of a complete pelleted diet.The Friesians were heavier than the Herefords, having 10%, 20% and 14% heavier empty bodies at 6, 13 and 20 months, respectively.At the same age, the Friesians had a greater percentage of empty-body weight as carcass muscle, carcass bone, total body water and total body ash than the Herefords but a lower percentage as dissectible fat and total body lipid. An analysis of linear body measurements showed no difference between breeds in the stage of development of external body dimensions at 20 months of age, and it was concluded that at the same age and stage of development of live weight or size, the Friesians were leaner than the Herefords.Relative growth coefficients of the fat depots showed late developmental growth in some intra-abdominal depots (omental and perirenal–retroperitoneal) but not in another (mesenteric). Relative growth coefficients of the omental, mesenterie and intermuscular depots were different between breeds. The Herefords deposited more dissectible fat subcutaneously than the Friesians whereas the Friesians deposited more in the intraabdominal depots. A multivariate index of fat partitioning, which was not influenced by age or stage of development of the fat depots, was not significantly correlated with fatness, suggesting no direct link between the pattern of fat partitioning and body-fat content.Breed differences in the distribution of fat within the subcutaneous and intermuscular depots were minor compared with the large difference in the partitioning of fat between depots. It was thus concluded that the factors controlling fat partitioning do not influence the distribution of fat within depots.
Fat deposition in Hereford and Friesian steers: 2. Cellular development of the major fat depots
Authors: Truscott T. G. , Wood J. D. , Denny H. R. 
Published: March 2009

SUMMARYThe size and number of recognizable fat cells (diameters greater than 5 μm) were examined at several sites in 42 Hereford and Friesian steers. Four, two and 15 animals from each breed were slaughtered at 6, 13 and 20 months of age, respectively, afterad libitumfeeding.For the 15 animals of each breed slaughtered at 20 months, biopsy samples of adipose tissue were removed at 10, 13 and 17 months from the 12th rib, midloin, rump and perirenal sites. Samples from these sites and from the brisket (subcutaneous), prescapular (intermuscular) and omental sites were also removed from the carcasses of slaughtered animals. Fat cell diameter (microscopic technique) and dry matter (from which lipid content was predicted) were measured on all samples. Measurement of fat depth (ultrasound) and surface area at the subcutaneous sites allowed changes in relative number of cells to be estimated during growth.From biopsied samples it was apparent that the perirenal depot grew almost exclusively through cell enlargement in both breeds. In contrast, the subcutaneous depot grew principally through cell enlargement to about 13 months of age and thereafter through both increase in number of cells and cell enlargement. The trigger for this increase in number of cells was possibly a critical average cell size, although this clearly did not operate in perirenal fat.Slaughter samples showed that cellularity changes with growth were similar in the perirenal and omental depots (intra-abdominal) whereas changes in the prescapular (intermuscular) site tended to parallel those in the subcutaneous depot.In relation to fat-free body weight (and therefore taking body size into account) both breeds had similar numbers of intra-abdominal and prescapular fat cells, but the Herefords had approximately double the number of subcutaneous fat cells compared with the Friesians.
Body heat storage in steers (Bos taurus) in fluctuating thermal environments
Authors: McLean J. A. , Stombaugh D. P. , Downie A. J. , Glasbey C. A. 
Published: March 2009

SUMMARYHeat stored in the body of cattle subjected to a daily 10 CC range of environmental temperature was measured by calorimetry and thermometry. The daily range of bodycore temperature of the animals was of the order of 0·5 °C but mean skin temperature cycled with a range of approximately 6 °C. Calorimetric estimates of changes in mean body temperature showed good agreement with thermometric estimates when core and mean body temperature changes were weighted in the ratio a: (1 – α) where α was found to be 0·85. This result is consistent with the findings of another study where cattle were subjected to abrupt changes in environmental temperature, the combined best estimate of a from the two studies being 0·86 ± 0·014 (s.E.). The 10 °C range of daily environmental fluctuation resulted in a daily variation of approximately 1 °C in mean body temperature, which is equivalent to the amount of heat produced by the animals every 40 min. It is suggested that a weighting factor α = 0·86 could be employed, using thermometry only, to estimate fluctuations in body heat storage which are likely to occur in animals subjected to fluctuating environmental conditions in the field.
Effect of dietary fat on the retention of calcium and phosphorus in buffaloes (Bos bubalis)
Authors: Nath K. , Agarwala O. N. 
Published: March 2009

SUMMARYFive feeding and metabolism trials were conducted on buffaloes fed different amounts of groundnut oil as a source of supplemental fat. Ca and P retentions were determined. The first two trials were conducted on 12 and 16 milch buffaloes and the other three trials on 15, 15 and 4 buffalo bulls. The dietary fat ranged from 1·32 to 6·00% of the ration in milch buffaloes and 0·51 to 6·33% in buffalo bulls. The retentions of Ca and P did not differ significantly with the percentage of fat in the ration. This showed that the phenomenon of formation of Ca soaps with fatty acids in non-ruminants with consequent wastage of Ca does not seem to be applicable to ruminants which have a much lower pH in the duodenum and upper jejunum. It is concluded that under practical conditions of feeding, within the usual range of dietary fat in ruminants, there is no likelihood of an adverse effect on Ca and P nutrition such as is encountered in non-ruminants on high-fat diets.