bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of dazomet and nitrogen fertilizer on successive crops of maize (Zea mays L.) grown for either grain or forage
Authors: Barnard A. J. , Hornby D. 
Published: March 2009

SUMMARYMaize was grown for grain or forage on the same site at Woburn for 7 consecutive years. Yields were satisfactory and there were no serious pest or disease problems, provided the small plots were netted until young plants were established. Different rates of nitrogen fertilizer were tested with and without annual applications of a soil sterilant, dazomet. Average yields of grain (85% dry matter) and forage (dry matter) were respectively 4·5 and 8·8 t/ha with 50 kg N/ha and 5·0 and 9·5 t/ha with 100 kg N/ha. Without dazomet there was a further increase with 150 kg N/ha. Weather influenced the response to nitrogen, and the response to a split dressing of the highest rate was variable. Except for plots receiving the split dressing of N in 1973 and 1974 dazomet always increased yields: grain yields were increased on average by 1 t/ha and forage by 1·6 t/ha. Dazomet-treated plots had taller and heavier plants with more stems, leaves and nodal roots, but fewer seminal roots than untreated plots. Dazomet-treated plots also had fewer migratory nematodes and smaller and less varied root myoofloras. Most of these differences were greatest in the young crop and possible reasons for this ‘early boost’ are discussed.
An assessment of accumulation of Cd, Cr, Gu, Ni and Zn in the tissues of British Friesian steers fed on the products of land which has received heavy applications of sewage sludge
Authors: Rundle H. L. , Calcroft Marian , Holt C. 
Published: March 2009

SummaryFifteen British Friesian steers were reared using grain and forages which had been grown on land which has had a long history of use for disposal of sewage sludges. The food consumption was recorded and samples of feedingstuffs analysed for Cd, Cr, Cu, Ni and Zn. The various components used in compounding the feedingstuffs were also analysed. After about 13 months the animals were slaughtered and samples of various organs and tissues obtained for analysis.The majority of the Cd, Cr, Cu and Zn came from sources other than uptake into plants. The largest single contributor was the high phosphate mineral supplement. No animal health problem due to the feed regime was encountered. Concentrations of cadmium in liver and kidney were slightly higher than average. Muscle cadmium concentrations of Cr, Cu, Pb, Ni and Zn were within the range of published values.
The effect of level of concentrate supplementation given with grass silage during the winter on the total lactation performance of autumn-calving dairy cows
Authors: Gordon F. J. 
Published: March 2009

SummaryA total of 140 British Friesian cows in their second or later lactation and with a mean calving date of 27 October (s.D. 18 days) were used in a randomized-block experiment over a 3-year period. The experiment was designed to examine the effects of level of concentrate given during the winter period, in addition to ad libitum access to grass silage, on total lactation performance. The silage had a mean dry-matter content and digestible organic matter in the dry matter of 206 and 698 g/kg respectively and the mean inputs of concentrates on the five treatments were 0–64, 0–89, 1–14, 1–38 and 1·59 t/cow (treatments 1–5 respectively). Sixteen replicates per treatment were housed in individual stalls during the winter period in order to facilitate the measurement of silage intake and the remaining animals in each year were maintained as a single group.All animals in each year grazed together as a single group at pasture at a mean stocking rate of 6–0 cows/ha and without supplementary concentrates.Level of concentrate supplementation had a significant linear effect on the intake of silage dry matter with the relationship between total intake of silage dry matter over the winter period (kg, y) and concentrate dry matter input (kg, x) being described by equation (1)
The incidence and effect of poisoning with Lantana camara in different cattle breeds
Authors: Frisch J. E. , O'Neill C. J. , Burrow H. M. 
Published: March 2009

SummaryThe incidence of lantana poisoning and its effect on mortality, growth rate and fertility were recorded from 1975 to 1982 in seven lines of Bos taurus and Bos indicus cattle and their crosses.Two Bos taurus Hereford × Shorthorn (HS) lines had higher incidences of poisoning and higher mortalities after poisoning than the Bos indicus based breeds.During the period of poisoning, live–weight gains of affected animals of all breeds were reduced but subsequent recovery was rapid. Lantana poisoning had no detectable effect on the fertility of animals affected at least 10 months prior to their first mating, irrespective of breed.Parasite control influenced the incidence of poisoning and mortality in genetically similar groups of HS cattle. This observation, when combined with the between-breed relationships between the incidence of lantana poisoning and susceptibility to environmental stresses suggests that the marked breed differences in susceptibility to lantana poisoning stem from differences in resistance to other environmental stresses, including cattle ticks. This offers little scope for selection of animals that are resistant to lantana poisoning per se but has practical significance in lantanainfested regions.
Effect of postnatal development and weaning upon the capacity of pig intestinal villi to transport alanine
Authors: Smith M. W. 
Published: March 2009

SummaryThe relationship between structure and the ability of piglet intestine to transport alanine has been determined during the first few weeks of postnatal life.Villus length halved without change in crypt depth during the 3rd week of postnatal life. A similar shortening of villi, accompanied by an increase in crypt depth, took place when 2-week-old piglets were weaned on to a solid diet. Weaning piglets at 3 weeks increased crypt depth without causing further shortening of villi.Alanine transport was shown, by quantitative autoradiography, to be largely confined to enterocytes in the region of the villus tip. The way in which this transport function developed was analysed further by fitting logistic growth curves to measurements of intra-enterocyte alanine concentration. The ability of enterocytes to transport alanine occurred earlier and alanine was accumulated to higher concentrations in enterocytes studied in 21- compared with 15-day-old unweaned piglets. Weaning piglets on day15 or 21 and measuring alanine transport 5 days later produced a pattern of development similar to that reported previously for adult animals.Transport of alanine throughout postnatal development showed sodium dependency. Effects of alanine on intestinal short-circuit current of weaned piglets were again similar to those recorded in adult animals.These results are discussed in terms of intestinal adaptation to a changing environment and in relation to the ‘notional capacity’ of a pig villus to transport amino acids during the early postnatal period of development.
The effect of variety and harvesting stage on forage production of barley in a low-rainfall environment
Authors: Droushiotis D. N. 
Published: March 2009

SummaryThree cutting stages, the boot stage, 50% heading and the milk stage of grain, were imposed on eight barley varieties at four sites, two in each of two successive cropping seasons. Dry-matter and digestible yield increased significantly when harvest was delayed from the boot to the milk stage but crude-protein content and digestibility declined with advanced maturity. A similar pattern of response was obtained in most cases when varieties were examined individually. Variety 628 produced the highest yield, 8·34 t D.M./ha, while the most digestible variety was Athenais with 61·9% digestibility. In low-rainfall regions harvesting at the later stages of maturity is recommended, to take advantage of the higher D.M. yields.
Quantitative digestion by sheep of carbohydrates, nitrogen and S-methyl-L-cysteine sulphoxide in diets of fresh kale (Brassica oleracea)
Authors: Barry T. N. , Manley T. R. , Duncan S. J. 
Published: March 2009

SummaryApparent digestibility of forage kale (cv. Maris Kestrel) was compared with that of mixed perennial ryegrass (0·85) and clover (0·15) herbage in two experiments. In a third experiment measurements were made of the partition of digestion between the reticulo-rumen and post-ruminal regions of the digestive tract in sheep fed kale, using intra-ruminal infusion of inert ruthenium phenanthroline and chromium-EDTA markers and time sequence sampling from the duodenum. Results in Expt 3 were compared with predicted values for a range of ruminant diets, including digestion of fresh perennial ryegrass and white clover.In Expts 1 and 2 the ratio of readily fermentable to structural carbohydrate (CHO) was much higher in kale (2·6–3·2) than in mixed ryegrass and clover herbage (0·6), and showed little difference between kale leaf and stem components. Apparent digestibilities of organic matter (OM), cellulose and hemicellulose were 80–90% for kale diets, varied little with changes in leaf/stem ratio, and were generally slightly higher than for mixed ryegrass and clover herbage. Calculated metabolizable energy (ME) concentrations were 12·0 and 11·7 MJ ME/kg D.M. for kale and mixed ryegrass and clover respectively.Despite large intakes of water-soluble CHO and pectins in kale-fed sheep in Expt 3, duodenal flows were small and respectively 92 and 98% of the total amounts digested were digested in the rumen. Ruminal cellulose digestion (95% total digested) was as predicted for normal ruminant diets, but less hemicellulose was digested in the rumen (71% total digested) than predicted. Total N flow at the duodenum was 5 g/day less than N intake, and respectively 27 and 66% of the N apparently digested was accounted for as total N absorption from the rumen and post-ruminal absorption of NAN. Calculated absorption of amino acids from the small intestine was less for the kale diet (14% ME intake) than for diets of fresh perennial ryegrass and white clover (20% ME intake). Possible reasons are that 10% more of the OM ingested was digested in the rumens of sheep fed kale than was predicted, that the ratio of dietary total N/100 g digestible OM was much less for kale (3·7) than for perennial ryegrass and white clover (5·6) diets, and that protein formed a lower proportion of the total N in kale diets (75%) than in diets of ryegrass and clover (90%). Despite 3·3 g of S-methyl-L-cysteine sulphoxide (SMCO) being consumed per day, none was detected in either rumen or duodenal contents or in faeces.In was concluded that complete conversion of SMCO to dimethyl disulphide occurred in the rumen, that dimethyl disulphide may have caused the depression in ruminal digestion of hemicellulose, and that the digestion products of kale are deficient in absorbed amino acids relative to other forms of energy, thus explaining responses to essential amino acid supplementation in lambs grazing kale.
A comparison of sample preparation and calibration techniques for the estimation of nitrogen, oil and glucosinolate content of rapeseed by near infrared spectroscopy
Authors: Starr Carol , Suttle Janet , Morgan A. G. , Smith D. B. 
Published: March 2009

SummaryPredictions of nitrogen, oil and glucosinolate concentration in rapeseed samples were made by near infrared reflectance analysis after various grinding treatments. Also examined were the effects of normalizing reflectance data and the possible advantage of using all combinations of two and three wavelengths in the calibration regression analysis over forward stepwise regression. The main conclusion was that drying the samples prior to a controlled grinding treatment gave the best results, although acceptable results for selection purposes could be obtained using whole seeds to predict nitrogen and oil. None of the treatments of the seed or reflectance data allowed acceptable prediction of glucosinolate content.
Effect of temperature and light intensity on resistance in marrow (Cucurbita pepo) to cucumber mosaic virus
Authors: Pink D. A. C. , Walkey D. G. A. 
Published: March 2009

SummaryPlants of Cucurbita pepoL. cvs Cinderella, Cobham Bush Green and Goldrush were inoculated with cucumber mosaic virus (CMV) and some grown at each of three temperatures (15, 20 and 25 °C) and three light intensities (13, 40 and 120 W/ma). Symptom severity in all three cultivars decreased with increased temperature but only for ovs Cinderella and Cobham Bush Green when the light intensity was raised. In general ov. Cinderella was most resistant and cv. Goldrush most susceptible, except at 25 °C, when most plants were symptomless.
The rates of nitrification of peat soils in British Guiana
Authors: Paul H. , Shariff M. A. A. 
Published: March 2009

A study has been made of some of the nitrogen fractions of the pegasse soils of British Guiana in virgin and exhausted conditions, that is, before and after cropping.1. Preliminary field experiments on the virgin and exhausted soils adduced strong evidence in support of the complaints made by farmers that the productivity in yields of the pegasse soils after continuous cropping for a comparatively short period is considerably impaired.2. The virgin soil showed an appreciable amount of nitrate nitrogen, while the exhausted sample indicated no nitrate. The latter soil, on the other hand, contained a higher amount of ammonia nitrogen measured by KCl extraction than the former soil.3. Nitrification studies with added ammonium salts indicated that under optimum conditions the nitrifying power of the exhausted soil was extremely low. Additions of sodium nitrate indicated that the nitrate was partially reduced to ammonia by the worn-out pegasse soil. The virgin pegasse, on the other hand, showed an appreciable rate of nitrification.
Studies on the oxalate contents of the leaves of certain varieties of Beta vulgaris
Authors: Baker C. J. L. , Eden A. 
Published: March 2009

1. Studies were made during the 1951 and 1952 seasons of the oxalate contents of the leaves of mangolds, sugar mangolds and fodder sugar beet.2. In all varieties greater concentrations of total oxalates were found during the summer months, the amounts diminishing gradually as the season advanced. Up to 12% was found in the dry-matter of mangold leaves and 9% in fodder sugar-beet leaves in July, these levels falling to 3% by mid-winter. There is some evidence that these changes are due in part to loss of outer leaves.3. Roughly one-third of the oxalates are present in water-soluble form. The addition of 1 part of chalk to 1000 parts of leaves, as has been generally recommended, is theoretically sufficient to render unavailable the soluble oxalates present during winter, but insufficient for leaves fed earlier hi the season.4. A number of observations showed small reductions in the soluble oxalate contents of the leaves due to wilting, but there were exceptions to this, and these appear to be related to sampling periods rather than to varieties.5. Insoluble oxalates appear to be unaffected by wilting and may show apparent increases in amount due to respiration losses of labile leaf constituents. The insoluble/soluble oxalate ratio is thus changed by wilting.6. It is suggested that the undesirable effects sometimes resulting from the feeding of beet leaves to livestock may not be due to oxalates, but that other factors present, which are labile during wilting, may be involved.
The assessment of structure in tropical soils
Authors: Pereira H. C. 
Published: March 2009

A comparison of methods of measuring the structural condition of cultivated surface soil was made for two important East African soil types.The soil samples were drawn from two field experiments: (i) a tillage trial in coffee on a porous red lateritic clay soil of recent volcanic origin; (ii) a rotation trial for cotton, on a red sandy lateritic loam of granitic origin.Of the measurements on soil cores, total porespace and field capacity (⅓ atmosphere) showed little change, while percolation rates, free-draining pore-space and a new rainfall acceptance test all reflected the observed field behaviour of the soils, and showed fairly close and highly significant correlation. Field sieving of dry clods gave highly significant differences in the lateritic clay, the stronger clods indicating the poorer soil condition. Drysieving for ½ mm. crumb was ineffective, as was wet-sieving after wetting under vacuum. Wetting by immersion gave some differences between treatments, but higher variability and no significant correlation with free-draining pore-space. Wetting by rainfall impact on dry crumbs gave the best wet-sieving tests on the clay soil. Different sieving techniques gave inconsistent results on the sandy soil. Crumb structure measurements are not efficient indications of structural conditions on these soil types, which are of wide occurrence in tropical countries.
Nitrogen transformations during the biological decomposition of straw composted with inorganic nitrogen
Authors: Bremner J. M. 
Published: March 2009

1. Nitrogen transformations during the decomposition of straw composted with ammonium carbonate have been studied by following the changes in (a) the amounts of inorganic and organic nitrogen; (b) the amounts of ammonia-, volatile base-, α-amino- and amino sugar-N liberated by acid hydrolysis of the organic nitrogen complexes; and (c) the amino acid composition of acid hydrolysates of the composts.2. Synthesis of organic nitrogen during the biological decomposition of straw composted with ammonium carbonate is not accompanied by any gross change in the distribution of the forms of organic nitrogen. A large fraction of the organic nitrogen synthesized is in the form of protein; a smaller fraction is in the form of amino sugar.
Effects of row width and planting density on growth and yield of two maincrop potato varieties. 2. Number of tubers, total and graded yields and their relationships with above-ground stem densities
Authors: Ifenkwe O. P. , Allen E. J. 
Published: March 2009

SUMMARYData are reported from three experiments from 1972 to 1974 which examined the effects of two row widths (66 cm and 132 cm) and five planting densities on number of tubers, tuber yields and tuber saleability of two maincrop potato varieties (Désirée and Maris Piper). Fewer tubers were generally found in 132 cm rows than in 66 cm rows; in 1972 reductions were most marked at high densities in both varieties and in 1974 effects were most pronounced in Maris Piper. Row width had little effect on total tuber yield at any stage of growth in either variety. The use of 132 cm rows reduced tuber greening, so that yields of saleable ware tubers at final harvest were not reduced by 132 cm rows in any year and in 1973 were higher in Désirée from 132 cm rows than from 66 cm rows. These results suggest that wider rows than are currently used in practice should be considered for maincrop potatoes, especially where water is not limiting.Increasing planting density increased total yields in both varieties although the responsesto the final increments in planting density were small. Yields > 38 and > 57 mm declinedat the higher planting densities in Maris Piper and the optimum above-ground stem densities for ware grades differed markedly in the two varieties. Good relationships between tuber yieldsand number of above-ground stems were found in all years and support the use of stems as thebasic unit of density in this crop.
Studies on reproduction in prolific ewes. 4. Sequential changes in the maternal body during pregnancy
Authors: Robinson J. J. , McDonald I. , McHattie I. , Pennie K. 
Published: March 2009

SUMMARYSeventy-eight Finnish Landrace × Dorset Horn ewes in lamb to Suffolk rams were slaughtered serially between 50 and 145 days of gestation. The mean litter size was 2·7. The daily feeding regime aimed to provide each ewe with 15 MJ of metabolizable energy (ME) in the first month of gestation and 9·4 MJ in the second and third. Thereafter the ewes were provided with a basal intake of either 9·6 MJ (low plane, LP) or 13·4 MJ (high plane, HP) plus 1·3 MJ for each foetus.For ewes with 2, 3 and 4 foetuses the mean percentage changes in maternal body weight over pregnancy were respectively — 5, — 10 and — 14 (LP) or + 3, — 2 and — 6 (HP). Changes in weights of blood, liver and the empty gastro-intestinal tract through gestation varied with the plane of nutrition but not with number of foetuses. In contrast, udder weight at parturition was dependent on number of foetuses but not on plane of nutrition.Increased hydration of the maternal tissues in late pregnancy tended to mask concurrent losses of body fat. For example, over the last 2 months, HP ewes carrying quadruplets lost on average 1·0 kg in body weight but 5·5 kg of (chemically determined) fat. The latter was lost at a rate which increased up to an average of 170 g/day over the last 2 weeks of pregnancy. Net changes in body protein were estimated to be relatively small, but there was some redistribution, including loss from muscle and gain by the udder. There was no evidence of any demineralization of the maternal skeleton.The practical significance of the changes in body composition is discussed, in particular that of the increasing rates of loss of body fat with increasing litter size. It is suggested that the dangers implicit in these rates of fat loss must be taken into consideration when deciding on dietary regimes and the timing of breeding cycles for highly prolific ewes, or indeed when embarking on a programme of increased prolificacy.
Composition of beef carcasses:I. Material, measurements, jointing and tissue separation
Authors: Pomeroy R. W. , Williams D. R. , Harries J. M. , Ryan P. O. 
Published: March 2009

SUMMARYOne side of the carcasses from 145 beef animals was weighed, measured and quartered. Measurements were made in the exposed eye muscle region which was then photographed. Measurements were made from the photographs and the quarters were jointed. Each joint was separated into lean, bone, intermuscular fat, subcutaneous fat and ‘other tissues’. The material is described in terms of breed, sex and side weight. Details of the measurements made are given and the methods of jointing and tissue separation are described. The latter was different in three groups of 30, 72 and 43 animals. The overall carcass composition in terms of lean, bone, intermuscular fat plus ‘other tissues’, and subcutaneous fat for the three groups is summarized and the reasons for including ‘other tissues’ with intermuscular fat are given.