bluuebunny/crossref_metadata_2025_split huggingface dataset:
The carotene content of certain species of grassland herbage
Authors: Smith A. M. , Wang Tung 
Published: March 2009

The total nitrogen and carotene have been determined in sixty-three samples of white clover, cocksfoot, rye-grass and timothy taken at different times during the growing season from various localities.Except for rye-grass, there was more carotene in the leaves and stems than in the heads or flowers. A late dressing of ammonium sulphate increased the carotene content of rye-grass by 55 and 17% in the leaves and heads respectively. The effects of lime and slag on the carotene content of cocksfoot and rye-grass were much less marked and there were no obvious effects due to environment.The predominant factor in determining both nitrogen and carotene, which were very closely related, was stage of growth. Grazing effected important increases in both constituents.
The role of exogenous plant regulators in the dormancy of onion bulbs
Authors: Abdel-Rahman M. , Isenberg F. M. R. 
Published: March 2009

SUMMARYExperiments were conducted to study the effect of plant injection with growth regulators on the dormancy of onion bulbs cv. Elba Globe. Application of abscisic acid induced early senescence of the leaves and prolonged the rest period of the bulbs. This effect was partially overcome by subsequent applications of gibberellin, auxin or cytokinin and totally overcome with the application of a mixture of the three hormones. Maleic hydrazide application prolonged the rest period by inhibiting both sprouting and rooting of the bulbs throughout the storage period. This inhibitory effect was not overcome by the subsequent application of auxin, gibberellin, kinetin, or their combinations. Ethephon application increased rooting of bulbs and partially overcame the effect of abscisic acid on dormancy.
Investigations on the root nodule bacteria of leguminous plants: XX. Excretion of nitrogen in associated cultures of legumes and non-legumes
Authors: Virtanen Artturi Ilmari , von Hausen Synnöve , Laine Tauno 
Published: March 2009

The associated growth of peas and different non-legumes (barley, oats, wheat, and potato) was investigated both under sterile conditions and in ordinary pot cultures. In the former case the medium consisted of quartz sand, and in the latter of clay or sandy loam soil, poor in soluble nitrogen. It is shown that nitrogen was transferred from the pea nodules to the non-legumes.In sterile cultures, where the excreted amino-acids cannot undergo decomposition, oats, wheat and barley utilized only a part of the excreted nitrogen, generally less than 50 per cent. In some instances, however, the barley took up considerably over 50 per cent of the excreted nitrogen. There was an apparent accumulation of aspartic acid in the medium of the associated cultures. In pot cultures, where the amino-acids may have been broken down by contaminating micro-organisms, the transfer of the excreted nitrogen to the potato exceeded 90 per cent.All experiments show that with increasing ratio of non-legumes to legumes the growth of the peas suffers, obviously from lack of nitrogen. Under these conditions, the excretion from the nodules increases to such an extent that the peas receive only a small fraction of the nitrogen fixed by the nodules. The major part of the carbohydrate material furnished by the pea for the amino-acid synthesis in the nodules is excreted into the medium. This naturally causes disturbances in the growth of the pea.
Fecundity of male rabbits as determined by “dummy matings”
Authors: Macirone C. , Walton Arthur 
Published: March 2009

A method of obtaining samples of semen from rabbit males by means of a dummy and artificial vagina is described. The volume of the semen, and the number of spermatozoa per cm. (density) and the total number of spermatozoa in the sample have been measured. The data obtained from these measurements have been analysed under the following headings:1. Relation between total volume and total number of spermatozoa. With an increase in the total volume of the ejaculate there is an increase in the total number of spermatozoa, but the relationship is not linear. The density of spermatozoa varies considerably.2. Seasonal variation. Seasonal variation in sperm production is not marked in these data. There is slight tendency for the numbers to be highest in the early part of the year and lowest in August and September when the animal is moulting.3. Individual variation. In each individual, variation is considerable. Differences between individuals are not marked, but as most of the animals were of low average fertility, it is probable that this result is not typical of male rabbits in general.4. Effect of successive matings with in a short period. In successive matings the number of spermatozoa diminishes rapidly. As the density is not much affected, the diminution is due to reduction in the volume of the ejaculate.5. Relation between the number of spermatozoa in the ejaculate and the number in the various sections of the spermatic tract. After a series of samples had been obtained, some males were killed and an estimate made of the number of spermatozoa present in various parts of the tract. From the results it is concluded that on ejaculation the vas deferens is practically emptied and that some sperm in the ejaculate come from the cauda epididymis.6. Observations on sexual behaviour. The sexual pattern of the male rabbit is described and the relation between sexual stimulation and sex drive is discussed.
A study of the effect of feeding oils to dairy cows and of the value of the Latin square lay-out in animal experimentation
Authors: Garner Frank H. , Sanders H. G. 
Published: March 2009

1. A description is given of an adaptation of the Latin square lay-out to experiments with dairy cows. Experiments were conducted to test the effect of adding various fats and oils to the ration, and since effects were rapidly produced the Latin square technique proved very efficient, experimental errors being rather lower than those usually obtained in experiments with crops.2. Seventeen separate experiments, including, in all, twenty-one different cows (many of whom were used more than once), were conducted; fourteen of these were short-term experiments with unit periods of 5 days, two were medium-term with unit periods of 10 days and one long-term with 20 days.3. Palm oil, butter, lard and possibly cotton-seed oil were found to increase butterfat yield, chiefly by raising the butterfat percentage of the milk. Soya-bean, linseed and whale oils were without effect. Cod-liver oil definitely decreased butterfat percentage and butterfat yield.4. It appears that the beneficial oils are those containing a large proportion of the saturated fatty acids.5. Experiments with the same oil were not always consistent, and it appears that the effect may vary from cow to cow, and also with the same cow at different times.
Studies in tropical soils: IV. Organic transformations in soils, composts and peat
Authors: Duthie D. W. 
Published: March 2009

1. Waksman's simplified scheme of fractionation was used in attempts to trace the organic transformations occurring in some tropical samples of composts, soils and peats.2. It was found that a useful partition of the nitrogenous substances into hydrolysable and resistant fractions could be effected by boiling with 5 per cent sulphuric acid for 6 hours.3. Two profile layers of a black calcareous Trinidadian clay soil were compared with two horizons of a prairie soil examined by Waksman & Stevens. The surface layers of both soils were found to be similar in chemical characters, but the lower subsoil layers of the Trinidadian soil gave evidence of a more advanced and profound degree of organic decomposition.4. Serial soil samples, taken from eight undisturbed natural profiles representative of humid tropical soil types occurring in Jamaica and Trinidad, were similarly examined.
An analysis of the factors determining yields in crosses between semi-dwarf and taller wheat varieties
Authors: Lupton F. G. H. , Oliver R. H. , Ruckenbauer P. 
Published: March 2009

SUMMARYThe growth and development of two semi-dwarf winter wheat varieties, of two taller varieties, and of random selections from two crosses between semi-dwarf and taller varieties were compared over 2 years. Changes with time of crop dry weight/m2, leaf area index and ear size were expressed as orthogonal polynomial regression coefficients. Significant correlations were obtained between yield, the polynomial coefficients and growth measurements relating to number of tillers and flag leaf area duration, but many of these variables were significantly correlated with each other. Multiple regression equations were therefore calculated expressing yield in terms of the variables. These showed flag leaf area duration and rate of ear growth to be the most important characters determining crop yield. The greatest reduction in total yield variance was obtained by the simultaneous consideration of characters relating to photosynthetic capacity and ear development. The significance of this finding in relation to the relative importance of ‘apos;source’ and ‘sink’ in determining grain yield are discussed.
Analysis of post-weaning growth in pigs
Authors: Smith A. D. Buchanan , Donald H. P. 
Published: March 2009

1. The post-weaning growth of 135 litters has been analysed with a view to determining the relationship of certain arbitrary subdivisions with each other. For this purpose, the weight increases during three periods of 28 days have been denned in two ways—first, by age, the periods being 10–14, 14–18, and 18–22 weeks, and secondly, by weight, the periods beginning at 40, 80 and 120 lb. and continuing as before for 4 weeks.2. When the periods are defined by age, the mean increase per pig per litter is affected by weaning weight, but not by litter size (Table III). The variability of the individual increases becomes greater as the pigs become older and heavier (that is, passing from one period to a later one), but less within a period as the rate of growth increases (Table IV). It was not affected by litter size.3. The distribution of individual weights became increasingly skew with age. This is regarded as a graphical illustration of the fact that while absolute rate of growth is increasing, initially small animals must fall farther and farther behind (Graph 3).4. The correlations between the average litter increases in different periods were calculated for litter sizes 6–11. In general, the coefficient for periods 1 and 2 was about 0·4, and for periods 2 and 3 about 0·6 (Table VI). This is interpreted to mean that, when judged by results over the whole time under observation, litters with a high correlation between the increases in weight during short periods are not properly comparable with those with a low correlation. By this method, differences in rate of growth having an important influence on carcass quality may be obscured.
The effect of pregnancy on hair growth and shedding in the guinea-pig. (With one text-figure.)
Authors: Strangeways D. H. 
Published: March 2009

SummaryThe effect of pregnancy on hair growth and shedding in the short-haired guinea-pig has been studied. It is shown that during pregnancy the amount of hair produced on defined areas of skin decreases until at the time of parturition and for 2 weeks afterwards practically no hair growth is taking place. This is followed by an increased output of hair substance, and hair production returns to its normal level after 11 weeks.
The Maintenance of Healthy Stocks of Potatoes in England
Authors: Bbyan H. 
Published: March 2009

1. An attempt to maintain the health of a stock of Scotch seed Majestic in England is described.A small stock of seed obtained direct from Scotland was split up into three equal portions A, B, C, which were grown isolated from each other and all other potatoes for three years (1927–9).A. Remained unrogued.B. Had all plants showing virus disease symptoms rogued out and the requisite seed saved from the remaining plants when mature.C. Had a similar quantity of seed saved from ostensibly healthy plants when immature.2. In a final chequer board yield trial fresh Scotch “stock” seed, which can be assumed to be above the average of ordinary Scottish seed, beat stocks A, B and C significantly. There was no significant difference in the yields from the stocks obtained by the two methods B and C and both stocks beat the mature unrogued stock A significantly.
The effects of drought on barley growth: models and measurements showing the relative importance of leaf area and photosynthetic rate
Authors: Legg B. J. , Day W. , Lawlor D. W. , Parkinson K. J. 
Published: March 2009

SUMMARYIn a field experiment on the effects of drought on spring barley the crop was protected from rain by automatic rain shelters. Various plots received irrigation at different times to give a range of drought treatments from full irrigation to no irrigation between emergence and harvest. The foliage area, light interception, stomatal resistance and leaf photosynthesis rate of five treatments were measured throughout the growing season, and a mathematical model has related the computed whole canopy photosynthesis to the measured total dry-matter yields at harvest. Hence, it was possible to estimate tha independent influences of drought on radiation interception, efficiency of use of intercepted radiation, and respiration. The analysis shows that for all treatments the decrease of intercepted radiation was the major factor in reducing yield, and it accounted for a loss of 30–40% for treatments that were stressed from the beginning of the season, and of 10–20% for treatments that were stressed after mid-May. Stomatal closure caused a reduction of up to 11% in daily photosynthesis, and the maximum effect was on plants that acquired a large leaf area before being stressed. However, the effect of stomatal closure integrated over the whole season was only 6% or less. Our measurements of internal resistance to carbon dioxide transfer were not precise enough to show significant differences between treatments; but increases of internal resistance, caused by stress, may have contributed to loss of yield.
Results from two barley experiments at Saxmundham, Suffolk, measuring effects of the fungicide benodanil on three varieties, given three amounts of nitrogen at two times 1973–4
Authors: Widdowson F. V. , Jenkyn J. F. , Penny A. 
Published: March 2009

SummaryMidas, a barley variety very susceptible to brown rust (Puccinia hordei), and two less susceptible varieties (Julia and Mazurka) were given three amounts of nitrogen (50, 100 or 150 kgN/ha) either at sowing (in March), in May, or half at each time. Benodanil sprays were applied to one half of each plot in June and again in July to control brown rust. Brown rust became more severe in 1973 than in 1974 and was most severe on Midas with 150kgN/ha. In 1973, there was most brown rust where all or part of the nitrogen was applied in May, but in 1974 there was least brown rust where all the nitrogen was applied in May, probably because dry weather limited its uptake.In 1973, when ample rain fell in spring and summer, grain yield was increased more by nitrogen given in May than in March, especially when benodanil was given. In 1974, little rain fell until July and then March nitrogen increased grain yield most whether or not benodanil was given. Top dressing of N (in May) produced a smaller straw yield than seed-bed dressing did in each year.Benodanil spray much decreased brown rust and increased yield of grain, but not of straw; the increase was greater in 1973 than in 1974, when brown rust was less abundant. Benodanil increased yields of all varieties, but that of the rust susceptible variety, Midas, most. Benodanil increased grain yield more, as more N was given to the barley, and more with N given in May than in March. It increased the amount of N removed by the barley grain, but not by the straw.
Effect of long term water deprivation on body weight and water intake of breeding ewes under semi-arid conditions
Authors: More T. , Sahni K. L. 
Published: March 2009

SummaryThirty-nine adult ewes of identical body size and age were randomly taken from the Chokla breed. They were divided into four groups which were allowed water once in 24, 48, 72 and 96 h. Seven ewes from each of the first, third and fourth groups were mated for the first time in the spring and for a second time in winter, so that they lambed in the monsoon and summer season respectively. All the ewes were maintained on uncultivated pasture. Watering once in 72 and 96 h caused body weight loss up to 26%, compared with those watered daily. The ewes which failed to maintain pregnancy lost more than 30% of their body weights due to watering only once in 96 h and there were about 43 and 100% lambing in the first and second breeding cycle of the same ewes. The remaining groups displayed 100% lambing. The water-intake increased significantly in the third month of pregnancy in the group allowed water daily and water consumption was found to be about 13% of body weight, whereas the values for those watered once in 72 and 96 h were 9 and 8% respectively. The water-deprived animals were able to drink up to 32 % of their body weights within 2–3 min. It is concluded that breeding ewes could be watered once in 72 h without any loss of lambing during summer.
A comparative method for describing the seasonal distribution of production from grasses
Authors: Corrall A. J. , Fenlon J. S. 
Published: March 2009

SummaryA standard method is proposed for establishing the seasonal pattern of production for grasses. The procedure consists in recording the yield from grass swards cut every 4 weeks and from which limitations to growth from the supply of water or nutrients have been removed. Four series of plots are harvested in rotation, spaced a week apart so that there is a routine of harvesting a constant number of plots on the same day each week. A statistical analysis is also described enabling comparisons to be made between the grasses under test. An example is given to illustrate the method and the results obtained.
Analysis of yield stability in field beans (Vicia faba L.) in the Northern Province of the Sudan
Authors: Yassin T. E. 
Published: March 2009

SummaryTen varieties of field beans, grown in different environments, were analyzed for genotypic stability of their seed yield. The linear responses to the environments were insignificant, but deviations from linearity were highly significant suggesting that the relatively unpredictable component of the genotype x environments interactions was more important in this material than the relatively predictable component. Environmental effects per se were very important in determining differences in mean seed yield. The relatively large deviations from linearity of variety IW may be due to powdery mildew disease. RB 29 was identified as a good yielding and stable variety in the range of environments tested.
Nutrient composition of the produce of the Broadbalk continuous wheat experiment II. Changes occurring during one season's growth
Authors: Chambers W. E. 
Published: March 2009

1. In the summer of 1945 samples of the growing crop were taken from eight Broadbalk plots. On all the plots the concentrations of nutrients in all parts of the plants decreased during growth. The compositions of the roots and stems and leaves varied with fertilizer treatment at all times of the season. The nutrient composition of the ears was only slightly affected by fertilizer treatment.2. The total uptake of nutrients by the crop increased to a maximum and then decreased. The losses of potassium and magnesium from the stems and leaves were particularly large, due to translocation into the ear but there were also net losses of potassium and calcium from the whole plant.3. The changes which occurred were similar on all plots and the effect of fertilizer treatment on plant composition was always related to the effect at harvest. There was no evidence that the composition of the crop at harvest differed radically from the composition earlier in the season.
Myoepithelial cells in bovine sweat glands
Authors: Goodall A. Myfanway , Yang S. H. 
Published: March 2009

1. Spindle-shaped myoepithelial cells with longitudinal myofibrils have been demonstrated in the sweat glands of Ayrshire and Zebu cattle.2. The cells in both breeds are similar in structure, location and arrangement.3. Under the polarizing microscope they are birefringent as is characteristic of other fibrillar structures.
Effect of egg transfer on the skin follicles and birthcoats of Finnish Landrace and Soay lambs
Authors: Burns Marca , Ryder M. L. 
Published: March 2009

SummaryThe birthcoats of Finnish Landrace lambs showed a wide range of halo-hair grades but all had strongly checked fibre type arrays, which were either Plain or Valley. Transfer to Welsh Mountain dams reduced the effect of prenatal check, giving fewer sickle fibres and increased halo-hair and/or super sickle A percentage. Transfer to Border Leicester tended to have the opposite effect. Fibre diameter measurements made on skin samples indicated an increase in primary fibre diameter in transfers into Welsh dams, but no difference in transfers into the Border Leicester.All Soay samples had Grade VII halo-hair density and Plateau or Saddle arrays. Transfer of Soay eggs to Finnish Landrace ewes increased the percentage of sickle fibres mainly at the expense of hairy-tip curly-tips. Skin samples from the transferred Soays indicated reduced primary fibre medullation, and evidence of retarded secondary follicle development.Thus in both breeds the birthcoat changed slightly in the direction of that of the foster-dam. There was, however, no indication that increased prenatal check was associated with increased foetal size. It is therefore concluded that changes in birthcoat as a result of egg transfer are more probably due to direct effects of the maternal environment than to the effect of foetal size as previously postulated.
Muscle weight distribution in four breeds of cattle with reference to individual muscles, anatomical groups and wholesale cuts
Authors: Charles D. D. , Johnson E. R. 
Published: March 2009

SummaryOne side of each of 51 carcasses of Hereford, Angus, Friesian and Charolais cross-bred steers was dissected and the weights of individual muscles and total carcass muscle were obtained. The percentage distribution of total carcass muscle weight in muscles and in. standard groups of muscles was determined. In addition, the percentage distribution of total carcass muscle weight in wholesale cuts was determined from the weights of whole and part muscles specified as comprising the respective cuts.Minor breed differences only were found in muscle weight distribution among muscles, groups of muscles and wholesale cuts. Similarity of muscle weight distribution in the different types of carcasses studied shows that carcass shape is not associated with differences in the distribution of muscle weight in wholesale cuts.