bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incomplete Latin squares
Authors: Yates F. 
Published: March 2009

A description is given of the statistical procedure appropriate for the analysis of a Latin square having missing the whole of one row, one column or one treatment, or one row and one column, or either and a treatment. These are the only types of incomplete Latin squares (except those which can be dealt with by the missing plot technique) for which a neat statistical analysis is possible.It is shown that incomplete Latin squares of these types give unbiased estimates of error and are therefore valid experimental arrangements. They are consequently likely to be of use when the experimental material is such as to preclude the use of a complete Latin square owing to the fact that the number in one or both of the natural groups is one less than the number of treatments to be tested.
Investigations in crop husbandry. III. Effect of time of application of sulphate of ammonia to wheat
Authors: Garner F. H. , Sanders H. G. 
Published: March 2009

1. Over a period of six years seven field experiments were carried out to study the effect of the time of application of sulphate of ammonia to autumn-sown wheat.2. Three experiments were located on light gravelly soil which had been farmed highly for some years, and in those three cases sulphate of ammonia decreased yield, irrespective of time of application; the reduction in yield was of the order of 10 per cent. and is ascribed to more lodging and greater incidence of “foot-rot”.3. Three experiments were located on heavy clay soil in poor condition; in these sulphate of ammonia gave percentage increases in yield of 18, 20 and 7.4. Evidence is produced that early dressings of sulphate of ammonia do not affect germination or plant establishment, but that they tend to increase tiller formation by the end of February.
Advanced sugar–beet seed
Authors: Longden P. C. 
Published: March 2009

SummaryA technique is described for speeding germination of monogerm sugar-beet seed. The optimum treatment was four cycles of wetting seed with its own weight of water and storing it in a sealed container for 24 hours before drying for 48 hours. The number of cells per embryo was doubled, seedlings emerged approximately 2·5 days sooner and seedling shoot weight was increased by 31 to 53%.
Manganese deficiency in peas and other crops in relation to the availability of soil manganese
Authors: Heintze S. G. 
Published: March 2009

1. Crops sensitive to manganese deficiency are generally healthy on soils with more than 0·3 mg. exchangeable Mn%, but they may also be healthy on soils with less than this amount.2. Other fractions of the soil manganese, including those which are either readily reducible or soluble in sodium hexametaphosphate, are no more successful than the exchangeable manganese in characterizing deficient soils.
Experiments on the use of home-grown foods for milk production. V. The protein requirements of growing dairy heifers
Authors: Blaxter K. L. , Price H. A. 
Published: March 2009

1. The changes which have occurred in the nutrition of young dairy stock are discussed. It is emphasized that any food shortage of a farm affects young cattle before the rations of the cows are reduced.2. An estimate of minimum protein level is developed using Mitchell's (1926) method.3. An experiment designed to show the optimal level of protein in the ration for growing stock showed a difference between this minimum estimate and the optimal. Some considerable economy in protein can, however, be effected in Wood & Woodman's (1936) standard is the one normally used to calculate rations.4. The growth of young cattle on protein supplemented wartime dietaries of straw is shown to be below that of heifers fed the rations more normal in peace time.5. Stunted cattle undergrown by 7–8 months when 18 months to 2 years old have been found. This has been attributed to the effects of wartime rations.
Long term effects of fertilizers on grassland: III. Effects on some soil properties
Authors: Heddle R. G. , Simpson K. 
Published: March 2009

SUMMARYEffects of N as ‘Nitro-chalk’, P as superphosphate, and K as KCl and K2SO4 on ‘available’ P, K and Mg were examined over 14 years. The area was under grass/clover regularly cut 6 times a year.Soil pH was maintained by annual applications of ‘Nitro-chalk’ supplying an average of 4 cwt CaCO3 and 174 lb N per acre. Superphosphate supplying 43 lb P per acre per annum increased available P (modified Morgan method) appreciably even on plots where more than this quantity was taken off in herbage. Applied N also consistently increased available P. It was thought that this was because P in the root system was rapidly mineralized. Applied K consistently reduced available P because of increased uptake in cut herbage, with no apparent increase in root P for mineralization.The amount of available K in soils which received no added K was fairly constant over the period for a given N treatment. About 40 lb/acre/annum of K was released by weathering.There was a very marked interaction effect between rates of N and K fertilizers on available soil K, the large increase in available K where K fertilizer but no N was applied being considerably reduced with increasing N rates. These effects directly reflected uptake of K in cut herbage.Residual values of applied P, K and Mg on the respective ‘available’ nutrients were considerable and persistent.Available Mg was reduced by increasing rates of fertilizer N and by fertilizer K.
The influence of energy intake on plasma levels of glucose, non-esterified fatty acids and acetone in the pregnant ewe
Authors: Davies P. J. , Johnston R. G. , Ross D. B. 
Published: March 2009

SummaryForty cross-bred ewes were individually fed from the end of week 13 of pregnancy to parturition on two diets whioh were designed to provide intakes of metabolizable energy above (treatment El) and below (treatment E2) the maintenance requirement of the non-pregnant ewe.Energy intake had no significant influence on birth weight of single lambs but twin lambs from ewes on treatment E1 were 25% heavier than twins from ewes on treatment E2. A net loss of body weight occurred between week 13 of pregnancy and the day following parturition in all groups of ewes. These losses represented 5 and 10% of body weight in ewes carrying singles on treatments E1 and E2 respectively. In ewes carrying twin lambs losses represented 11 and 16% of body weight on treatments E1 and E2 respectively.Levels of plasma N.E.F.A. and acetone were used to characterize the state of nourishment of ewes at 16, 18 and 20 weeks pregnant. Values obtained indicated that ewes carrying one lamb on treatment El were ‘moderately’ undernourished. Ewes carrying one lamb on treatment E2 and those carrying twin lambs on treatment E1 were undernourished to a similar degree characterized as bordering between ‘moderate’ and ‘severe’. Ewes carrying twin lambs on treatment E2 and all those carrying triplets were ‘severely’ undernourished.
The use of vaginal sponges in spring breeding of Mutton Merino and cross-bred ewes
Authors: Goot H. , Schindler H. 
Published: March 2009

SUMMARYFifty-nine Mutton Merino and cross-bred 2-year-old and older ewes were allotted to two groups according to age, weight and breeding performance in the preceding 1966/67 in-season. In the experimental ewes the treatment started on 22 March 1967 and consisted of vaginal sponges (Syncro-Mate) inserted for 17 days and 750 i.u./ewe of P.M.S. injected on the day of the removal of the sponges.As from 1 March, all the ewes were ‘teased’ daily but hand service commenced on 20 April, to coincide with the 13th day after the removal of the sponges.At the time of sponge insertion, approximately a third of the ewes, in each group, were already cycling. The treatment advanced the average post-treatment oestrus by 8 days, out of a possible 15 days, synchronized it in 70% of ewes and shortened the tupping season in 97% of treated ewes to 9 days (23 days in controls), but otherwise the performance of the treated ewes (and their offspring) did not differ from that of the controls. In both groups forty ewes lambed (68%) and fifty lambs were born (85%). Out of nineteen dry ewes, five were in anoestrus and in at least nine, an early death of the embryo could be suspected. Among the reproductive activities during the preceding in-season, date of weaning, days of suckling and barrenness may be implicated in the failure to breed in the spring.
Residual value of basic slag, Gafsa rock phosphate and superphosphate in a sandy podzol
Authors: Mattingly G. E. G. 
Published: March 2009

SUMMARYSurface soils (0–15 cm) from a field experiment on a sandy podzol were used to evaluate the residues from basic slag, Gafsa rock phosphate and superphosphate (using ryegrass in pots), and to measure the solubility and buffer capacity during cropping, and the distribution of the residual phosphate in different particle-size fractions of the soil.After applying P at about 3·6 g P/m2/year for 6 years, residues of the three P fertilizers were equivalent but after applying more P (9–11 g P/m2/year) for a further 8 years, basic slag and rock phosphate gave larger labile P values, were more effective for ryegrass and buffered soils more than residues of superphosphate. The percentage recoveries of P from the surface soils were approximately 7, 40 and 65 % of the total applied in 8 years as superphosphate, basic slag and rock phosphate respectively.Residues from basic slag (mainly 75–20 μm particles) accumulated in the < 20 μm fraction of the soil. Rock phosphate (mainly 200–20 μm particles) dissolved more slowly and about one-half of the material > 20 μm remained in the sand fractions of the soil.Residues from rock phosphate maintained values of ½pCa + pH2PO4 and pH–½pCa consistent with the solubility of fluorapatite, even when P was removed from the soil by exhaustive cropping with ryegrass. Residues from basic slag were more soluble than hydroxyapatite.
The effect of intra-ruminal feeding on the intake of silage
Authors: McLeod D. S. , Wilkins R. J. 
Published: March 2009

SUMMARYA ryegrass silage with pH of 3·8 was prepared and part was neutralized to pH of 5·4 with sodium bicarbonate. Sheep were fed ad lib. in four treatments in which the two silage feeds were fed with either all the feed being consumed per os or with the introduction of silage (15 g D.M./kg LW0·75 per day) directly into the rumen through a fistula. Intake per os was significantly higher (P < 0·001) for the modified silage than for the original silage and was significantly lower (P < 0·001) for the treatments which included feeding per rumen rather than all the food being consumed per os. Feeding per rumen resulted in a small but significant (P < 0·05) increase in the total (per os + per rumen) intake of both types of silage. This increase in intake through feed being introduced directly into the rumen suggests that factors sensed in the oro-pharyngeal region which were by-passed with this treatment may have some limiting effect on the intake of both these silages. The effect of the introduction of feed directly into the rumen on intake per os was similar for the two silage feeds, despite much higher levels of consumption of the modified silage for both feeding methods. This suggests that the increase in intake brought about by partial neutralization was not mediated through this treatment affecting any oro-pharyngeal limitation on the intake of silage.Volatile fatty acid concentrations in the rumen were higher for the modified silage treatments, but differences between silage treatments for molar proportions of volatile fatty acids, rumen pH and rates of cellulose digestion were non-significant. The initial digestion of cellulose was slower, the molar proportions of acetic acid were lower and of propionic acid higher for treatments which involved feeding per rumen rather than all the food being consumed per os. These observations are discussed in relation to the use of the intra-ruminal feeding techniques and to possible factors limiting the intake of highly acid silages.
Effects of nitrogen fertilizer, plant population and irrigation on sugar beet: II. Nutrient concentration and uptake
Authors: Draycott A. P. , Durrant M. J. 
Published: March 2009

SUMMARYThe concentration of nitrogen, phosphorus, potassium, sodium, calcium and magnesium was measured in the dry matter of sugar beet from four field experiments (1966–9). All combinations of four amounts of nitrogen fertilizer (0–1·8 cwt/acre), four plant populations (8800–54000 plants/acre) and irrigation were tested, which gave a wide range of plant size and yield. Nutrient concentration and uptake by the crop were also greatly affected by the treatments.Nitrogen fertilizer and irrigation increased uptake of nitrogen by the crop but increasing the plant population had little effect on uptake and decreased the concentration of nitrogen. Sugar yield was related to the total nitrogen concentration in tops and roots and to uptake. There were optimal values of nitrogen concentration for maximal sugar yield, but the optima were greatly affected by plant population. Leaf colour was a good guide to nitrogen concentration.Phosphorus concentration was affected little by the treatments but cation concentrations were greatly affected. In general, uptake of all the elements was increased by all treatments – the exception was sodium, which decreased as the plant population increased but this was balanced to somo extent by increased potassium uptake.
The interrelationship of some components of forage quality
Authors: Thomson A. J. , Rogers H. H. 
Published: March 2009

SUMMARYTo produce forage crop varieties of improved quality, the plant breeder must consider both the content of the quality components and their interrelationships. The methods used to examine the interrelationships involve simple correlations and path analyses. In the path analyses a dependent variate is specified which is completely and additively determined by a number of independent variates. The amount of variation present in the dependent variate accounted for by variation in each of the independent variates is calculated. The effects of an increase in the mean content of one of the quality components on the other components in the path system is predicted.As an example of the method, data for two years is analysed from timothy polycross progenies grown as swards and spaced plants. Primary and subsequent growths are compared.There are inconsistencies in the interrelationships of the quality components between years and between swards and spaced plants. Although only phenotypic statistics were calculated, the findings have implications in relation to plant breeding.
The effects of nitrogenous fertilizer on the nutritive value of artificially dried grass
Authors: Blaxter K. L. , Wainman F. W. , Dewey P. J. S. , Davidson J. , Denerley H. , Gunn J. B. 
Published: March 2009

SUMMARY1. A field trial in which a sward, predominantly of S. 24 ryegrass was fertilized with 248, 301, 532 or 589 kg N/ha showed that a maximal yield of 13·1 tonnes/ha of artificially dried grass could be obtained from four harvests in the year.2. The materials harvested ranged in crude protein content from 10·1 to 23·6% and in apparent digestibility of dry matter from 72 to 76%. The amounts of the grasses voluntarily consumed by sheep were slightly and significantly lower for those containing the least N × 6·25.3. In feeding trials with twenty-five steers, a barley diet was compared with a diet entirely of dried grass from the 3rd and 4th harvests from an area in the same field which had received 487 kg N/ha. The cattle given the barley diet consumed 8·7 kg/day and gained 1·22 kg/day. Those given dried grass consumed 8·9 kg and gained only 0·85 kg/day. Carcass quality of animals given dried grass was significantly lower than of those given the barley diet.4. Calorimetric trials were made using two herbages from the first harvest (501, 532 kg N/ha) and all four herbages from the third harvest. In each of the six experiments three sheep were each given three amounts of a herbage, and in addition were fasted. Fifty-four calorimetric observations each lasting 5 days and eighteen fasting metabolism measurements were made.5. With both 1st and 3rd harvests, methane energy losses fell and urinary energy losses increased with the level of N fertilization. Faecal energy losses were little affected by fertilizer application and the metabolizable energy (kcal/g D.M.) was 2·8 (11·7 kJ/g) for 1st harvests and 2·6 (10·9 kJ/g) for 3rd harvests. There was a slight decline in metabolizable energy/g D.M. with N application for the 3rd harvests.6. The net energy values of the grasses for maintenance were 1·99 kcal/g D.M. (8·4 kJ/g) for the 1st harvested material and 1·84 kcal/g D.M. (7·7kJ/g) for the 3rd harvests. Net energy values for fattening, however, were 1·28 kcal/g D.M. (5·4kJ/g) for 1st harvests and 0·87 kcal/g D.M. (3·6kJ/g) for 3rd harvests. There were no significant effects of level of N fertilization.7. The poorer nutritive value for fattening of the 3rd harvested grass, corresponding to an efficiency of utilization of metabolizable energy of only 33%, was contrary to prediction from equations relating nutritive value to either chemical composition or to metabolizable energy. The results of the calorimetric work, however, agreed with those of the feeding trial with cattle.8. Combination of the results of the various trials showed that it was possible to obtain 1400 kg live-weight gain/ha from a system of husbandry based on high fertilizer use and artificial drying of herbage. With a barley system a maximal output/ha would be less than half this amount.
The growth and yield of tall and short sorghums in Nigeria
Authors: Goldsworthy P. R. 
Published: March 2009

SUMMARYA Nigerian, long-season, sorghum produced 15 tons of dry matter/acre in about 155 days, but the grain yield was small (2000 lb/acre or 2242 kg/ha) because only part of the dry matter formed after heading went into the grain. In contrast, an American, short-season hybrid which formed only from one-half to one-third as much dry weight as Farafara, gave over 4000 lb of grain/acre (4484 kg/ha) in 100 days. A Nigerian sorghum of intermediate height and a long-season hybrid, produced by crosses between Nigerian varieties and an American, short-season sorghum, gave larger yields than the tall variety because they formed more heads/unit area and more grains/head.Crop growth rates of the three long-season sorghums sown in June increased to a peak in July, but declined sharply to very small values in September, and then increased again very rapidly at the end of September as heads emerged. The most important factors causing the decline were a decrease in radiation and a loss in dry weight from decay and detachment of dead leaves. An increase in radiation at the end of September and developmental changes associated with head emergence contributed to the increase in growth rates just before heading.A large proportion of the dry weight formed after heading in Farafara accumulated in the stem but a smaller proportion in the other long-season variety and the longseason hybrid. There was an inverse relationship between the increase in stem weight and the yield of grain. For large grain yields, sorghums are needed that will produce heads with sufficient grains to accommodate all the assimilate that the leaves produce at the end of the rains when crop growth rates are increasing.
Nitrogen requirement of cereals: 2. Multi-level nitrogen tests with spring barley in south-western England
Authors: Needham P. , Boyd D. A. 
Published: March 2009

SummarySeventeen experiments with spring barley testing seven amounts of nitrogen were made on commercial farms in Somerset, Devon and Cornwall between 1965 and 1968. Crop measurements and determinable site factors were only partially successful in accounting for differences between sites and between years in optimal N and efficiency of N use below optimum.The actual optima were found to differ considerably from predicted N requirements based on past cropping and summer rainfall.
The effects of a wide range of nitrogen rates on some chemical constituents of the herbage from perennial ryegrass swards with and without white clover
Authors: Reid D. , Strachan N. H. 
Published: March 2009

SummarySelected herbage samples from a 6-year experiment in which nitrogen rates between 0 and 897 kg/ha were applied annually on perennial ryegrass swards were analysed for nitrate-nitrogen, true-protein and non-protein nitrogen, water-soluble carbohydrate, potassium and sodium content and for amino acid composition. The nitrate-nitrogen content of the herbage increased with increasing nitrogen rate from 224 kg/ha upwards, but the potentially toxic level of 220 mg/100 g dry matter was not reached until the annual nitrogen rate was about 560 kg/ha. On average, at the 897 kg nitrogen/ha rate the non-protein nitrogen content had increased to 27·5% of the total nitrogen yield, and 40·3% of the non-protein nitrogen yield consisted of nitrate nitrogen. Nitrate content was shown to be a sensitive indicator of the level of nitrogen nutrition of the herbage, the optimum nitrogen rate for dry-matter production coinciding with a nitrate-nitrogen content of approximately 100 mg/100g dry matter. The amino acid composition of the herbage varied little with either the rate of nitrogen or the date of cutting. It was demonstrated that, on average, a 1% unit increase in the crude-protein content of the herbage was accompanied by a 1% unit decrease in the carbohydrate content. The sodium content of the herbage increased with increasing nitrogen rate up to between 448 and 560 kg/ha, but the potassium content showed little variation.
The effect of three different growth rates on some offal components of cattle
Authors: Murray D. M. , Tulloh N. M. , Winter W. H. 
Published: March 2009

SummaryThis paper describes the effect of three different growth rates on some offal components of Angus cattle. The growth rates were: high (H, 0·8 kg/day), low (L, 0·4 kg/day) and high-maintenance (HM, 0·8 kg/day followed by a period during which body weight was held constant).Equations are presented which enable the weights of the offal components to be calculated within the body weight range 300–440 kg.For most tissues, weights in the H group were greater than in the L and HM groups and included: liver, rumen-reticulum, small intestine and the total alimentary tract. Weight of fat trimmed from the rumen-reticulum, omasum, large intestine and total alimentary tract was also greater in the H than in the L and HM groups. The reverse situation held for head, feet and tail and the spleen.In spite of these differences between groups in weights and composition of offals, the carcass composition in all groups was similar (Murray, Tulloh & Winter, 1974). It appears that, at a given body weight, changes in the offals may buffer the carcass against change in composition when cattle are exposed to different growth patterns.