Showing papers in "The Journal of Agricultural Science in 1940"
TL;DR: In this paper, the dependence of the coefficient of diffusion, D, upon the porosity, S, of a granular solid is investigated experimentally, and it is shown that a curve connecting D/D0 and S can be drawn which is independent of the nature of the solid, its moisture content and, within limits, its texture.
Abstract: The dependence of the coefficient of diffusion, D, upon the porosity, S, of a granular solid is investigated experimentally. For steady state conditions, using carbon disulphide and acetone vapours, it is shown that a curve connecting D/D0 and S can be drawn which is independent of the nature of the solid, its moisture content and, within limits, its texture. For a limited range of values of S (0·0 < S < 0·7) a good approximation is D/D0 = 0·66S and over this range the diffusion coefficients are larger than those found by Buckingham for carbon dioxide.Investigation of the non-steady state shows that in soils the attainment of pressure equilibrium is retarded by adsorption, and it is suggested that Buckingham's low values for steady-state conditions can be attributed to premature observations of the diffusion rates; the steady state had probably not been attained when his measurements were made.
480 citations
TL;DR: The relative changes with age in these characters have been studied in a series of male pigs killed at monthly intervals from birth to 7 months, establishing the general order of development during post-natal life of the body proportions, tissues, and anatomical units.
Abstract: 1. With the object of establishing the general order of development during post-natal life of the body proportions, tissues, and anatomical units, the relative changes with age in these characters have been studied in a series of male pigs killed at monthly intervals from birth to 7 months. The study is to be regarded in the light of a preliminary investigation, providing a background to experimental studies on the influence of nutrition on the growth and development of the pig.2. Growth in body proportions, when measured both photographically and by the weight of the individual anatomical regions, conforms to the law of developmental direction, exhibiting a well-defined anterior-posterior gradient from earlier to later developing regions. The limbs appear as relatively early developing parts with the fore limbs slightly earlier developing than the hind.3. The major body tissues exhibit marked differential growth behaviour; skeleton, muscle, and fat develop in that order. This situation has its origin in the differential rates of growth of the three tissues, in consequence of which the earlier developing skeleton makes a greater proportion of its growth earlier in life than does muscle, while the latter makes a greater proportion of its growth earlier than does the still later developing fat.4. Within any one tissue, the individual anatomical units or regions of the body similarly show well-defined differential growth relationships. Thus, the skeletal units of the head and trunk exhibit an anterior-posterior gradient in their order of development, while the bones of each limb show a centripetal gradient, the upper units being later developing than the lower units. To an even more marked degree, both the muscle and the fat surrounding these skeletal units afford evidence of similar gradients in these tissues.
293 citations
TL;DR: In this paper, the yields of grain and straw per plot were estimated by weighing the total produce on each plot and taking samples, usually from the sheaves, to estimate the ratio of grain to total produce.
Abstract: In a number of cereal experiments, three on wheat, three on barley and one on oats, the yields of grain and straw per plot were estimated by weighing the total produce on each plot and taking samples, usually from the sheaves, to estimate the ratio of grain to total produce. This paper discusses the sampling errors of this method. The method proved considerably less accurate than was anticipated from previous calculations made by Yates & Zacopanay. Amongst the reasons which are suggested to account for this are the larger sizes of plot and sampling unit used in these experiments and the additional variability introduced by the presence of weeds, undergrowth and moisture.Nevertheless, the method appears to be substantially superior to the older method of cutting small areas from the standing crop, without weighing total produce, only about one-quarter of the number of samples being required to obtain results of equal precision.The samples were taken both by an approximately random process and by grabbing a few shoots haphazardly from each of several sheaves. The grab samples gave on the whole a slightly higher yield of grain, the greatest positive bias being 6%, but were otherwise just as accurate as the random samples. Since the grab samples can be selected and bagged in about one-third of the time required for random samples, their use is recommended for the majority of the samples required in any experiment.The validity of an approximate formula for calculating the variance of a ratio (in the present instance the ratio of grain to total produce) is discussed briefly in an appendix.
237 citations
TL;DR: By quantitative control of the plane of nutrition, twenty closely inbred pigs have been made to conform to four major variations in the shape of the growth curve from birth to 200 lb live weight.
Abstract: It is impracticable to give a detailed summary of the many findings of.this experiment; attention is confined, therefore, to the major aspects and the general principles emerging.1. By quantitative control of the plane of nutrition, twenty closely inbred pigs have been made to conform to four major variations in the shape of the growth curve from birth to 200 lb. live weight. A high rate throughout (High-High), a high followed by a low rate (High-Low), a low followed by a high rate (Low-High) and a low rate throughout the period (Low-Low) afforded comparison between animals of the same weight but different age and between animals of the same weight and age but with differently shaped growth curves. The relative effects of the treatments upon the development of body proportions and anatomical composition have been studied.
132 citations
TL;DR: In this article, an approach for measuring the rate of diffusion of carbon dioxide through granular solids is described and the results obtained with it are shown to conform to the curve connecting D/D0 and S previously obtained for carbon disulphide and acetone.
Abstract: Apparatus for measuring the rate of diffusion of carbon dioxide through granular solids is described and the results obtained with it are shown to conform to the curve connecting D/D0 and S previously obtained for carbon disulphide and acetone. The equation D/D0 = 0·66S, which it is suggested should replace Buckingham's equation D/D0=S2, is applied to a discussion of soil aeration, and it is shown that at all porosities the rate of diffusion of carbon dioxide from the soil is sufficient to account for normal respiration without invoking the assistance of meteorological changes. A further application of the equation to water vapour movement in soils is briefly discussed.
126 citations
TL;DR: The influence of extremes of high and low planes of nutrition during the first 16 weeks of post-natal life upon the growth in body proportions and in anatomical composition has been studied experimentally in six pairs of closely inbred pigs.
Abstract: No attempt will be made to give a detailed summary of all the findings of the present experiment. It is rather our purpose to draw attention to the main principles emerging.1. The influence of extremes of high and low planes of nutrition during the first 16 weeks of post-natal life upon the growth in body proportions and in anatomical composition has been studied experimentally in six pairs of closely inbred pigs. Quantitative differences in nutrition operative from birth have resulted in an average live weight at 16 weeks of 113 lb. in the High-Plane and 37 lb. in the Low-Plane animals.2. In body proportions, the head, ears, neck, legs, and body length are penalized relatively less by inadequate nutrition than are body depth, loin, and hindquarters. Conversely, good nutrition favours most the latter characters. These effects upon body form are similarly evident i n the gross weight of the different anatomical regions involved. Low-Plane animals to a large extent retain the proportions of the juvenile and High-Plane approach the conformation of the adult
118 citations
TL;DR: The foetus developed in the opposite horn of the uterus to the ovary which ovulated at the onset of pregnancy in five out of seven mares and in one mare as early as the 16th day of pregnancy.
Abstract: 1. The length of oestrus in mares varied from 3 to 54 days, although in most cases it was 7–8 days. 2. The length of dioestrus varied from 5 to 30 days, but in most cases was 11–16 days. 3. Ovulation occurred in most cases on the last day of oestrus, but a considerable number of ovulations occurred on the 1st and 2nd days before the end of oestrus, and in a few cases from the 5th day before the end of oestrus to 1 day after the end of oestrus. 4. Artificial insemination of mares was equally effective in the intervals of 24, 48 and 72 hr. before ovulation but was unsuccessful in intervals of 2 and 4 hr. after ovulation. 5. Pregnancy was diagnosed in all mares by rectal palpation on the 23rd day and in one mare as early as the 16th day. 6. The foetus developed in the opposite horn of the uterus to the ovary which ovulated at the onset of pregnancy in five out of seven mares. 7. Ovulation occurred in one mare on the 23rd day of pregnancy. 8. Gonadotrophic hormones had no effect when given in the anoestrous period (November to March). 9. Ovulation was induced in 20–40 hr. in most cases after the intravenous injection of 1000–2000 mouse or rat units of pregnancy urine extract intravenously, provided a fairly mature follicle was present in the ovary at the time of injection. When this ovulation occurred, the duration of oestrus was shortened.
71 citations
TL;DR: An investigation of the metabolism of a number of Light Sussex cockerels has shown that there exists a rhythm in the metabolism during fasting amounting to about 9% as between morning and night observations, the former being the higher by the percentage stated.
Abstract: An investigation of the metabolism of a number of Light Sussex cockerels has shown that there exists a rhythm in the metabolism during fasting amounting to about 9% as between morning and night observations, the former being the higher by the percentage stated. Two methods were adopted to exclude the effect of variation in the activity of the birds at different times of day. In the first, the birds were artificially stimulated during the normal period of repose in such manner as to give periods of approximately equal activity by day and by night. In the second, the movements of the birds were recorded by a system of “point scores”, and regression equations were deduced from a large number of such experiments so as to make it possible to reduce the metabolism observations to a basis of zero activity. The results obtained by these two methods of procedure were in good agreement with one another. The metabolism in the standing position is 40–45% above that in the sitting position, a figure considerably above that for the increase of metabolism as between the lying and standing positions usually found in quadrupeds, while at the moment of rising the heat output may occasionally be trebled, but averages about cent per cent above sitting. The former of these observations is of importance in estimating food requirements as our experiments show that generally speaking rather more than 12 out of each 24 hr. period is spent standing when the birds are kept in cages. It follows that the sitting metabolism must be increased to allow for this when the figure is being used for computation of rations. The large heat increase on rising to the standing posture is of such short duration as to exert little influence on the mean metabolism over a 24 hr. period.
45 citations
TL;DR: This study confirms the picture presented by the statistical comparison based on carcass measurements of the same breeds and crosses at constant weight described and discussed in Part II, and the concept of early and late development as a fundamental factor in meat production is demonstrated.
Abstract: It is not intended to present a detailed summary of the many points arising out of this investigation. The following represents merely a brief statement of the field covered and the major features emerging. 1. Complete anatomical dissection of eleven wether lambs at approximately 4·5 months old and 40 lb. carcass weight and five wether hoggets at approximately 13 months and 60 lb. carcass weight provided material for a comparative study of the anatomical composition and characters of different breeds and crosses of which the individuals concerned were selected as representative. 2. In both lambs and hoggets this study confirms the picture presented by the statistical comparison based on carcass measurements of the same breeds and crosses at constant weight described and discussed in Part II. 3. The breed differences in the relative development of the different regions of the body and the relative development of the major tissues, bone, muscle and fat in different joints and the total carcass have been studied in relation to carcass quality. 4. From the differential development of the different parts and tissues of the body in the various breeds and crosses, the concept of early and late development as a fundamental factor in meat production is demonstrated. 5. The proportional development of the various parts of the body and its major tissues in lambs and hoggets is compared. Regions of an intermediate rate of development are relatively best developed in the hoggets. In the total carcass, bone has increased least, muscle only slightly more and fat most, with an increase in age from 4·5 to 13 months and body weight from 40 to 60 lb. This is in line with the order of the development of the tissues. 6. The differential effect upon differentially developing tissues of the plane of nutrition is advanced as a major factor influencing the relative differences between lambs and hoggets. 7. Variations, affecting the value of the animal for meat production, in the number of vertebrae in the different anatomical regions have been described. 8. The bearing of the many factors discussed and principles elucidated upon practical problems of lamb and mutton production has been considered.
36 citations
TL;DR: The mineral compositions of the clays from a red earth and a black cotton soil from Hyderabad, Deccan State, India, occurring in close proximity in the field are determined as mentioned in this paper.
Abstract: The mineral compositions of the clays from a red earth and a black cotton soil from Hyderabad, Deccan State, India, occurring in close proximity in the field are determined. Both soils are derived from the same or from very similar parent rocks, a coarsely crystalline granite or gneiss. For both soils there is practically no variation in the mineralogical composition of the clay throughout the profile, but for any given clay there is some variation with grain size. The main contrast between the two is that the red clay contains predominantly kaolinite or halloysite, whereas the black clay contains mainly beidellite, a member of the montmorillonite group. The topography appears to be the principal factor associated with this difference in minerals, and the processes of weathering believed to have produced the contrasted clays are discussed with reference to experiments on the leaching of felspar in the laboratory and on hydrothermal synthesis.
25 citations
TL;DR: No significant difference was found between the average digestibility coefficients recorded with the zebu and the grade oxen and the slight differences in feeding values were of no practical significance.
Abstract: 1. With three different groups, each of two zebu and two zebu × Ayrshire grade oxen, and ten typical East African feeding stuffs, no significant difference was found between the average digestibility coefficients recorded with the zebu and the grade oxen. 2. The slight differences in feeding values were also of no practical significance. 3. Some of the zebu × Ayrshire cattle were 3/4 and others 7/8 Ayrshire but the higher grading to the European breed apparently did not affect the digestive powers.
TL;DR: In this article, the influence of storage in the light and in the dark at ordinary temperature and in a heated room at 70-80° F on the carotene content of finely ground artificially dried grass stored in paper sacks and jute sacks was studied.
Abstract: 1. The influence of storage in the light and in the dark at ordinary temperature and in a heated room at 70–80° F. on the carotene content of finely ground artificially dried grass stored in paper sacks and jute sacks was studied. There was an initial drop in carotene content from 61·1 to 46·5 mg./100 g., i.e. 23·9%, in the first month, and a total loss of 31·4% during 6 months' storage (August to February). No difference could be detected either between treatments or types of containers. 2. There was a marked loss of carotene during 13 months' storage of baled artificially dried grass and of hays, amounting to 30–40% of the original value. 3. Two methods of estimating carotene were compared. The method of Ferguson & Bishop (1936) gave higher results than the method of Peterson, Hughes & Freéman (1937). The difference is probably due to incomplete extraction in the latter method. 4. Chromatographic analyses of “carotene” fractions from the above grasses showed the presence of coloured impurities amounting to 20·5–33·8% of the total recovered pigments. 5. As these impurities are biologically inactive, chromatographic analysis or the use of special solvents are probably necessary for the accurate determination of carotene in forage.
TL;DR: In this article, the size distribution of clods in the field is determined by simple sieving of the soil without any pre-treatment provided the soil is not too wet, i.e., clods smaller than 3 mm.
Abstract: 1. It is possible to determine the size distribution of clods in the field by simple sieving of the soil without any pre-treatment provided the soil is not too wet. There is a personal factor involved in the sieving, but with care and training this will not affect comparisons of results obtained by that person. If the soil is too wet the individual clods smaller than 3 mm. stick together on the 3 mm. sieve. This sticking together is first apparent on the 3 mm. sieve but may become appreciable on the ¼ in. (6 mm.) sieve. No certain way was found for overcoming this difficulty.2. There appears to be no best method for determining the size distribution of the soil crumbs, i.e. of the water-stable aggregates in the soil. The method and the technique must be chosen so as to give the maximum amount of useful information. If an appreciable proportion of the crumbs are larger than ½ mm., a water-sieving method is practically essential.3. The method of wetting to be used can only be chosen from a consideration of what information is wanted. If possible it would be desirable for general purposes to use a very slow or a vacuum wetting technique and a very rapid wetting technique such as wetting the soil by immersion in water.4. The decision whether air-dry or field-moist soil should be used depends entirely on the information needed. For general purposes the use of air-dry soil is recommended.
TL;DR: The comparative nett energy for fattening of Sussex ground oats and white maize meal have been determined on Light Sussex cockerels by difference experiments with a direct calorimeter and there was no significant difference in the utilization of metabolizable energy from the two cereals.
Abstract: 1. The comparative nett energy for fattening of Sussex ground oats and white maize meal have been determined on Light Sussex cockerels by difference experiments with a direct calorimeter.2. The mean values for nett energy per gram dry matter, nett energy/ metabolizable energy, metabolizable energy per gross feed energy and digestible energy per gross feed energy were as follows:3. There was no significant difference in the utilization of metabolizable energy from the two cereals. The higher nett energy of the white maize meal was due to its higher digestibility.We again welcome the opportunity of expressing our indebtedness to Mr G. A. Childs for his assistance in carrying out the experiments.
TL;DR: A method is described by which small quantities of indolyl acetic acid can be detected and measured quantitatively, depending on the effect of this substance on osmotic pressure of root hair cells of wheat seedlings, and it was found that farmyard manure tended to increase the quantity present.
Abstract: A method is described by which small quantities of indolyl acetic acid can be detected and measured quantitatively, depending on the effect of this substance on osmotic pressure of root hair cells of wheat seedlings. Full details are given of the procedure adopted and the precautions which it was found necessary to take, and suggestions are put forward as to how the method might be rendered more accurate if necessary. Possible sources of e\"rror are also discussed. An experiment is described in which this method is used to determine what effect is produced by different manurial treatments on the content of indolyl acetic acid in the soil. It was found that farmyard manure tended to increase the quantity present.
TL;DR: 1. In the Eastern Counties of England, annual wastage from milk recorded dairy herds amounts to 29·3 % of the number of cows at the beginning of the year, and average length of productive herd life in milk recorded herds is 3·4 years.
Abstract: 1. In the Eastern Counties of England, annual wastage from milk recorded dairy herds amounts to 29·3 % of the number of cows at the beginning of the year. 2. Average length of productive herd life in milk recorded herds is 3·4 years. 3. Average length of total productive life in milk recorded herds is probably a little more than 4 years. Average length of total productive life in all herds is probably longer, and may be of the order of 5 years. 4. Deaths of cows are equivalent to 10·4% of the total wastage, and to a mortality rate of 3·0% of the number of cows at the beginning of the year. 5. During the three-year period 1934–5 to 1936–7, cows leaving the herd realized an average of £10. 10s. 6d. per head. The average market value placed upon heifers when they entered the milking herd was £20. 14s. per head, while cows for replacement purposes cost an average of £22. 5s. per head. 6. Of all replacements, 67·7 % are heifers, but not all of these are home-bred. In annual valuations, 49·0 % of cows are described as homebred, 50·6% as purchased and 0·4% as unknown.
TL;DR: Differences in the manganese content of size groups suggest that peas of uniform size should be selected for analysis when the relativeManganese levels of different samples are to be tested.
Abstract: 1. An outline of recent investigations on the cause of marsh spot in pea seeds indicates that the disease is caused by a deficiency of available manganese in the soil. 2. The symptoms of the disease are very briefly described. 3. The methods of analysis used by the writers for determining the amounts of manganese in whole peas and in different parts of peas are described. 4. As no loss of manganese was found to result from soaking the peas in water for 24 hr., soaked peas were used for dissection in preference to dry peas. 5. Referring to the diseased peas, the highest level of manganese was found in the peripheral tissues of the cotyledons, followed by the germ and seed-coat. Only slight traces of manganese were found in the healthy and in the necrotic tissue from the centre of the cotyledons. All parts of the healthy seed were richer in manganese than the corresponding parts of the diseased sample. In addition, the order of distribution was different; notably in that the tissue from the centre of the cotyledon contained a higher level than the seed-coat, and the germ a higher level than the outer layers of the cotyledon. 6. A given weight of small peas proved to contain less manganese than the same weight of large peas selected from the diseased sample. The reverse was found to be true for similar size groups selected from the healthy sample. These differences in the manganese content of size groups suggest that peas of uniform size should be selected for analysis when the relative manganese levels of different samples are to be tested. 7. It is suggested that migration of cell contents from the necrotic tissue of diseased peas may partly account for the differences in manganese content of healthy and diseased peas.
TL;DR: The results are described of twenty-two experiments carried out on the feeding of bacon pigs at different centres throughout Great Britain, in the course of which nearly 400 pigs were fed according to three different scales of rationing.
Abstract: The results are described of twenty-two experiments carried out on the feeding of bacon pigs at different centres throughout Great Britain, in the course of which nearly 400 pigs were fed according to three different scales of rationing. All the pigs were fed on the same scale until reaching 100 lb. live weight, when they were eating 4 lb. of meal per head per day. From this stage three different levels of feeding were followed; in each case the daily allowance reached a maximum when the pigs were 170 lb. live weight. The amounts being fed were then: 7 lb. 8 oz., 6 lb. 5 oz. and 5 lb. 3 oz. per head per day respectively.
Journal Article•
TL;DR: In this paper, an examination of carcass reports from two groups of bacon pigs (comprising eleven litters and seventy-five pigs) was made to determine whether the variation in growth rate of normally reared pigs was associated with differences in carcass measurements.
Abstract: 1. An examination of carcass reports from two groups of bacon pigs (comprising eleven litters and seventy-five pigs) was made to determine whether the variation in growth rate of normally reared pigs was associated with differences in carcass measurements. The method adopted was to fit orthogonal polynomials to the third degree to the last 10–11 fortnightly weighings converted to logarithms. 2. The residual standard deviation after fitting was about 2–4%. For present purposes, the fitting of second degree parabolae appeared adequate.
TL;DR: In this paper, an account has been given of the percentages of nutrients in the dry matter and weights of nutrients of potato plants throughout growth under six fertilizer treatments, including balanced manuring (N2PK) and unbalanced manuring.
Abstract: 1. An account has been given of the percentages of nutrients in the dry matter and weights of nutrients in tops, tubers and roots of potato plants throughout growth under six fertilizer treatments. 2. Manurial treatment affected dry-matter content of tops but not of tubers. 3. Balanced manuring, as represented by N2PK treatment, resulted in tubers in which nitrogen content of dry matter declined with age. The effect of the K was to lower the nitrogen, phosphorus and calcium contents, to increase chlorine content of all parts of the plant, and to maintain a much higher and more constant concentration of potassium in tops and roots. With unbalanced manuring the nitrogen content of the tubers was more constant. 4. Manuring with nitrogen only raised the content of potassium in the dry matter of all parts of the plant. 5. Nitrogenous manuring, whether alone or in combination, raised the nitrogen content of the dry matter of all parts of the plant, a smaller proportion of which was present as protein. Calcium and chlorine contents were lowered. 6. Phosphate manuring in conjunction with nitrogen depressed the concentration of potash in the dry matter of all parts of the plant. 7. N2P plants were the first to attain their maximum uptake of all nutrients, namely, about 7 weeks from appearance above ground, at which time N2PK plants had absorbed only 40% of the quantities finally noted. 8. No losses of elements were observed in the plants which received balanced manuring (N2PK), but losses of calcium and chlorine occurred in all other plants, amounting on the average to 25 and 37% respectively, but being highest in N2P plants. A significant loss of potassium occurred in N2 plants and a highly suggestive loss of phosphorus occurred in N2P plants.
Journal Article•
TL;DR: Evidence was obtained which shows that treatment with P.U. at the time of service increases the fertility of cows which show regular oestrus but nevertheless fail to conceive, believed that this condition is often due to failure to ovulate, and to deficiency of progesterone following ovulation.
Abstract: 1. The fertility of three sterile bulls was restored by injections of human pregnancy urine extract (P.U.). 2. Cows which failed to exhibit oestrus were treated by injections of P.U. Three out of five cows responded within 24 hours to intravenous injections of 5 c.c. P.U. (2500 rat units) and one out of four to an injection of 3 c.c. P.U. Two out of five cows responded immediately to a series of three intramuscular injections of 2 c.c. P.U. and one cow responded to a single intramuscular injection of 2 c.c. P.U. In addition four cows failed to respond immediately to four intramuscular injections of 2 c.c. P.U. 3. Evidence was obtained which shows that treatment with P.U. at the time of service increases the fertility of cows which show regular oestrus but nevertheless fail to conceive. It is believed that this condition is often due ( a ) to failure to ovulate, and ( b ) to deficiency of progesterone following ovulation. We are grateful to Prof. R. Rae and Mr K. W. C. Campbell for their co-operation. Part of this work was carried out during the tenure by one of us (H.M.S.W.) of a Research Grant from the Ministry of Agriculture and Fisheries.
TL;DR: Lucerne drilled at a constant seed rate per acre, in narrow rows, gave a greater yield per acre than when drilled in rows 10½ and 14 in.
Abstract: As a result of one detailed experiment and four demonstrations carried out on the University Farm at Cambridge the following conclusions can be drawn:1. Lucerne drilled at a constant seed rate per acre, in narrow rows (3½ and 7 in.), gave a greater yield per acre than when drilled in rows 10½ and 14 in. in width. Over a four-year period the yield of dry matter per acre from narrow rows was half a ton more than from wide rows. No evidence was obtained that weed infestation is reduced by narrow drilling.2. The broadcasting of 5 lb. of trefoil per acre at the time the lucerne was drilled had no effect on the total yield or on weed infestation.3. Wild white clover broadcast at the rate of 2 lb. per acre at the time of drilling the lucerne slightly reduced the yield of lucerne in the first harvest year, but subsequently it served to secure some control of weeds, and thereby favoured the persistence of the lucerne. Differences in yield associated with sowing wild white clover were, however, slight.4. Commercial cocksfoot broadcast at the rate of 10 lb. per acre at the time of drilling the lucerne led to very considerable increases in total yield (nearly 3 tons per acre of dry matter over a four-year period). The increments were obtained principally during the spring growth, and some loss of lucerne plants was suffered, so that in a very dry summer the total aftermath yield was slightly reduced. Since cocksfoot almost completely controlled weeds and its mixture with lucerne was very suitable for hay or for silage, it is regarded as a plant that may be included in a lucerne ley with advantage.
TL;DR: This review of the testing problem suggests the conclusion that empirical tests are limited in their significance and reliability, and that only an increased knowledge of the fundamentals can afford a truly scientific approach.
Abstract: 1. For both genetical and methodological reasons, tests for quality, in the majority of breeding schemes, are not required at the early stages of the breeding process. 2. Reliability and definition of any one empirical test is not sufficient to safeguard against losses of valuable material. 3. It is suggested, therefore, that as a rule agronomically promising lines should be carried on to a stage where comprehensive tests, using a number of selected methods, can be carried out, preferably over a number of seasons. It may be questioned whether a combination of such tests as the wholemeal fermentation and the gluten swelling tests (Pelshenke, 1938a) would suffice. In the light of the available evidence a testing system might be suggested comprising baking tests together with such “indirect” and, better still, “analytical” methods as will afford accurate information of an analytical nature. 4. This review of the testing problem suggests the conclusion that empirical tests are limited in their significance and reliability, and that only an increased knowledge of the fundamentals can afford a truly scientific approach. It should be admitted that the plant breeder, with his insistence on empirical tests where fundamental knowledge was lacking, has side-tracked the cereal chemist from the narrow path of scientific approach all too often. It is questionable whether this has been to the ultimate advantage of wheat breeding. 5. Inheritance studies on quality should greatly facilitate the task of the breeder. They will become feasible and valuable only when the nature of the desirable characters and the true significance of the testing methods are clearly understood.
TL;DR: In this article, the desirability of conserving young pea-pods for purposes of winter-feeding has been discussed, particularly at the present time, for the purpose of feeding live stock.
Abstract: Attention is directed in this paper to the desirability, particularly at the present time, of conserving, for purposes of winter-feeding, the pea-pods that accumulate in large quantities at the factories during the pea-canning season. Conservation on the farm is best carried out by the method of ensilage, young pea-pods, such as are obtained in the factory, giving rise to a very satisfactory type of silage without the use of molasses. Broad-bean-pods, on the other hand, do not lend themselves to successful conservation by ensilage, owing to the fact that they become “slimy” in the process and yield an unpalatable product. Both pea-pods and bean-pods are conserved in the factory by the method of artificial-drying. One such process is described in the present paper. The final product in both cases is obtained as a fine brown meal. Pea-pod meal, in some respects, particularly in regard to its satisfactory content of protein and lime, has a composition not unlike that of the leguminous hays. The similarity, however, does not extend to the fibrous constituent, pea-pod meal having a very much lower fibre content than the hays. An outstanding characteristic of pea-pod meal is its richness in sugar, no less than 16·5% of the dry matter consisting of a mixture of sucrose and invert sugar. It is the presence of this abundance of sugar that accounts for the favourable fermentation that takes place when young pea-pods in the fresh condition are conserved as silage. Bean-pod meal displays the same general features in respect of composition, but is distinctly poorer in lime and sugar than the pea-pod meal. Pea-pods and bean-pods, both in the fresh and artificially-dried condition, contain very little carotene and have, therefore, little or no significance as a source of this vitamin A-precursor in the feeding of live-stock.
TL;DR: Monthly aqueous extracts of soils which have been under wheat and barley cropping on the Woburn light sandy loam soils, with various manuring show very great similarity in the amount and character of the materials extracted in the wheat and the barley soils.
Abstract: 1. Monthly aqueous extracts of soils which have been under wheat and barley cropping on the Woburn light sandy loam soils, with various manuring show very great similarity in the amount and character of the materials extracted in the wheat and the barley soils. 2. Water-soluble phosphoric acid and potash are in extremely small amount where these manures have not been applied during the fifty years’ treatment, but, in spite of this, the amount of these constituents does not appear to be a limiting factor in determining the yield of either wheat or barley. The phosphoric acid is much higher in the plots treated with phosphatic manures, and the potash is slightly higher in those treated with potash manures, but these facts do not seem to have secured a seriously higher yield.
TL;DR: Individual dates for the termination of the cycle occur at so many points throughout the total range that this must either indicate a multiple factor situation or that the genes involved show a considerable range of expression.
Abstract: 1. Individual birds have a characteristic date for the termination of the egg laying cycle. 2. The date of cessation of production at the end of the pullet year is not a reliable indication of the bird's potentiality in this respect. 3. The longer the birds are retained the greater is the chance of distinguishing the true date. 4. Individual dates for the termination of the cycle occur at so many points throughout the total range (from July to December) that this must either indicate a multiple factor situation or that the genes involved show a considerable range of expression.