ALBERT

Description: Feeding trials with sheep, subsisting out-of-doors on typical winter rations of known dry-matter and starch-equivalent content, have been carried out during the winters of 1933–4, 1934–5 and 1935–6. Records have been kept over these periods of the live-weights of the animals and their daily consumption of dry matter and starch equivalent.It has been found that the standards of appetite, in terms of lb. dry matter, proposed by Prof. T. B. Wood are uniformly too high, a result in harmony with the findings of Prof. J. A. S. Watson and co-workers at Oxford. It is suggested that Prof. Wood's values should be multiplied throughout by the factor 0·85 in order to obtain reasonable measures of the appetites of sheep at different live-weights.The data from the feeding trials have been used in an attempt to decide between the old and the recently proposed standards for the maintenance starch-equivalent requirement of the 100 lb. sheep, namely, 0·74 and 1·26 lb. of starch equivalent per day. The results point to the reliability of the higher figure, and it is shown that the results of recent work on the energy metabolism of sheep are in harmony with this conclusion.A table embodying a revision of Prof. Wood's feeding standards for sheep is included in the paper.

Description: From metabolism experiments carried out on the pigs enumerated in the first paper of this series the following conclusions are drawn:(a) The metabolism in a state of inanition appears to be more a function of a power of the weight than of the true surface area as determined by the photographic method.(b) Hogs born in the summer and autumn of one year appear to show two maxima of metabolism; one almost immediately, as has been observed previously, and another during the following summer, provisionally ascribed to the effect of light on thyroid activity, produced by the intermediary action of the anterior pituitary.(c) Actual, and theoretically computed average growths are shown to agree remarkably well in the case of eleven of the pigs which were treated in an exactly similar manner. Individual growth curves showed no such agreement. This is considered to strengthen the evidence for the writer's previously stated view that nett energy is a statistical rather than a physiological constant.

Description: Many estimates have been made of sperm production in various species, but in most cases examinations have been made infrequently or with irregular intervals between successive collections. Since during a period of sexual rest spermatozoa may accumulate in the epididymis, or with longer periods may undergo disintegration and absorption in the vas and ampulla (Simeone & Young, 1931), the number ejaculated at an particular collection will not necessarily reflect the level of sperm production in the testis. Moreover, there is the possibility that copulation may actually stimulate spermatogenesis. In horses, Chang (1943) found that more sperms were ejaculated if collections were made frequently and at regular intervals. In the present experiments an attempt has been made to determine the effect of frequency of collection upon the sperm production of rams, the collections being taken at regular intervals and for a definite period, in this case ten days.

Description: A technique for measuring the appetites of sheep on pasture is described.Results are given to show that sheep consume a bigger ration, in terms of lb. dry matter, when on pasture than when subsisting out-of-doors on the winter type of diet composed of hay, swedes (or kale) and concentrates. This difference was noted even on grass that had deteriorated in quality, in one case as a result of hot, dry weather in early summer, and in a second case as a consequence of cold, dry weather in spring. With young, leafy pasturage at its best, however, the distinction is most marked.In the March of 1934, to quote but one example, four pure-bred Suffolk wethers, of live-weight varying from 120 to 181 lb., were shown to consume, on a diet of concentrates (350 g. daily), swedes (ad lib.) and chaffed hay (ad lib.), only 80–88 per cent of the amounts of dry matter predicted on the basis of Wood's feeding standards. During the following May, when grazing leafy pasturage of very good quality (digestion coefficient of organic matter = 81·l per cent), the appetites of the same sheep (range of live-weight now from 137 to 201 lb.) were found to have undergone a striking stimulation, the mean daily consumption of dry matter now being from 104 to 117 per cent of the amounts predicted from the standards. This implied that the sheep were consuming 1·13, 1·37, 1·13 and T53 lb. respectively more dry matter per day than they would have eaten had the diet consisted of hay, concentrates and swedes. The increased appetite is to be attributed to the superior palatability of the young grass.

Description: A laboratory study has been made of nitrification rates of the soil's own nitrogen, ammonium sulphate and certain organic nitrogen compounds. It is shown that nitrification in this soil is substantially normal, with no striking differences from that in soils of other arid regions.I am indebted to H. Greene and E. M. Crowther for access to their earlier unpublished work on nitrification in Gezira soil, and to O. W. Snow of this Service for advice during the course of this work.

Description: A method is presented for the preparation of a sensitive and diagnostic stained antigen for the detection of fowls suspected of infection by the organisms found in epidemic bacillary white diarrhoea (pullorum disease).Evidence is presented that an antigen prepared from organisms grown in a medium which provides for the peculiar growth requirements of the anaerobic organism associated with anaerogenic pullorum, is more sensitive than antigens prepared from organisms grown on media which lack these peculiar growth factors.A stained antigen has been prepared which is agglutinated by pullorum antisera in 15 sec. at 4°C. and in 6 sec. a t 15°C. and which is not agglutinated by normal sera in 5 min.The author wishes to thank the Directors of Messrs J. Bibby and Sons, Ltd., for permission to publish these papers.In particular he would thank Mr J. Pye Bibby for his keen interest in the investigations and for his loyal support throughout.In addition he wishes to thank Miss Margaret Davies for her assistance in the bacteriological investigations, and Miss Margaret Shafto for laboratory work and the compilation of relevant data.

Description: An experiment involving twelve pens of twenty-five pullets demonstrated that two types of dried potatoes compared favourably with cereals, as regards their effects on egg production, when up to 42½% of each product was included in the mash.The records of the experiment, as regards (a) the number of eggs laid in 12 months, (b) the mean weight of eggs during the year, and (c) the change in live weight during the year, were studied by analysis of variance, using the approximate method of Yates (1933) for obtaining standard errors of pen means from the variance within pens. Similar analyses of the number of eggs laid in the month were carried out for each month separately. The latter analyses indicated the months in which increased production was obtained from the superior rations, and showed that duplicate pens had reacted similarly to the experimental feeding. The results of the statistical analyses are set out in some detail as an example of method.

Description: 1. Dressings of 12–100 lb. borax per acre resulted in marked temporary ‘yellowing’ of bean seedlings. Dressings of 25 lb. or more depressed the stand and reduced the yield.2. Determinations were made to ascertain the distribution of boron within the treated plants and to measure the uptake of boron from the soil. The relevant figures are quoted in the text.

Description: Evidence is presented, based on feeding tests, that vitamin A metabolism is adversely affected when meat meal having a vitamin A consuming power in vitro is included in the diet of chicks.Evidence is presented, based on feeding tests, that when fish meal having no vitamin A consuming power in vitro is fed to chicks in a basal ration which produces negligible mortality, the addition of such fish meal to the ration does not appreciably increase mortality.Evidence is presented, based on feeding tests, that when fish meal having a vitamin A consuming power in vitro is fed to chicks in a basal ration which produces negligible mortality, the addition of such fish meal to the ration causes appreciable mortality.

Description: The main object of the present investigation was to test the inference from the results of previous trials that a diet composed substantially of cereal and weatings, with a small percentage of lucerne meal or grass meal, and supplying 7% of white-fish meal up to 90 lb. live weight and no protein supplement at all thereafter, should provide all the protein needed for the maximum rate of growth in bacon pigs and the production of carcasses of satisfactory quality, when fed at the rates shown in the feeding chart in Table 3.Two separate trials were carried out, and both the individual-feeding and group-feeding techniques were employed. In Trial I the control treatment A supplied the standard allowances of high-protein supplement, consisting of 10% of white-fish meal from weaning to 150 lb. live weight, and 5% of extracted soya-bean meal from 150 lb. to slaughter at about 200 lb. The white-fish meal in the rations of the pigs on treatment B was restricted to 7% up to 90 lb. live weight, and from this stage onwards the high-protein supplement was entirely omitted from the diet. The rest of the diet in both treatments consisted of barley meal and weatings, with a small percentage of lucerne meal, care being taken also to safeguard the animals against mineral deficiencies.

Description: Trichlorethylene-extracted palm-kernel meal is not an essential factor in the production of six-day disease.A comparison of the results of tests 1, 2 and 3 clearly indicates that under the same conditions and with similar chicks, some diets tend to produce six-day disease and some do not.

Description: The experiments of Briggs & Shantz led them to conclude that the “wilting coefficient” is a soil “constant” which is (a) independent of the kind of plant used as indicator, (b) independent of the conditions under which the plant was grown, and (c) directly related to several other soil constants.Subsequent research as well as an examination of their own results has shown that (c) is untrue, while (a) and (b) are substantially correct for hygrophytes and mesophytes. Earlier writers have been led to wrong conclusions regarding (a) and (b) through assuming (c) to be correct and through disregarding the particular nature of “permanent wilting” as defined by Briggs & Shantz.The fact that considerable variation is to be found between the osmotic pressure found in different plants, in different parts of the same plant and in the same part under different conditions is not at variance with conclusions (a) and (b) when properly understood.An important factor making for the substantial constancy of the “wilting coefficient” for a given soil is the extreme steepness of the curve connecting suction pressure and soil moisture content, in consequence of which differences of suction pressure of unquestionable significance from the standpoint of plant physiology give rise to differences in soil moisture content that are too small to be detected.

Description: When a factorial experiment involves many factors each of which is tested at two levels, economy of space and material may be effected by using only a fraction of a complete replicate of all possible combinations of levels of the factors. The consequence is that each main effect and each interaction has one or more aliases, and the experiment cannot distinguish which member of a set of aliases is responsible for an observed difference in yields. For less than five factors, this feature prevents fractional replicate designs from being much use; for five or more factors, the fraction can be so chosen that main effects and two-factor interactions have only higher order interactions as their aliases, and the possibility that these are important may often be ignored. Within the fraction of a replicate chosen for an experiment, confounding of interactions may be introduced in order to reduce the block size.Designs likely to be useful in field experiments are those for six factors in four blocks of eight, for seven factors in eight blocks of eight, and for eight factors in eight blocks of sixteen or in sixteen blocks of eight; in the first of these a two-factor interaction is amongst those confounded, but elsewhere all main effects and two-factor interactions are unconfounded. The method of construction of the blocks, for these designs and those involving more factors, has been described, and an example of the statistical analysis of experimental results (which presents no special difficulties) has been given.

Description: This paper deals with the final phase of the investigations described in the two papers immediately preceding it in the present issue of this Journal. These earlier papers may therefore be consulted for complete details concerning the general design and wider issues of the work as a whole (Woodman & Evans, 1938a, b).

Description: 1. Substantial control of covered smut of wheat, Tilletia caries, was obtained when seed was treated with an approved organo-mercury seed disinfectant using both rotational and gravitational machines for mixing.2. Good control of leaf spot of oats, Helminthosporium Avenae, was also obtained, using an approved organo-mercury seed disinfectant and mixing grain and powder together in a model rotational-type machine.3. The model rotational machine gave an even mixing of grain and seed disinfectant with as few as forty-eight turns. Twenty-four turns was almost as effective but the mixing was much less even.4. The gravitational machine was not so efficient in producing an even mixing as the rotational machine as assessed by the control of covered smut of wheat.5. There was an indication that the rotational machine gave a better disease control.6. Improvement was effected in the efficiency of mixing with the gravitational machine by the addition of a felt lining to the feed hopper.

Description: 1. A study has been made of the relative development of some regions in the fleece of twin lambs of a Suffolk ♂ × Suffolk (Border Leicester-Cheviot) ♀ cross during growth. The different regions develop in the following order: shoulder → leg → belly → tail. It is concluded that an improved animal is one in which the latest developing part of the fleece has the least possible number of undesirable fibres at the earliest possible age. The breeds of sheep begin their wool improvement by changes in the earliest developing regions (shoulder) and finish it in the latest (tail).2. The properties of the fleece studied were the colour of the fibres, the medullated fibres, the fineness of the fibres, and uniformity of fibre size. In general a relationship is found between the stage and rapidity of development of the area, and the properties of the fibre. The intensity of the colour is stronger during the early active stages of development. There is a tendency to lose some kinds of coloured fibres, and to diminish the intensity of the colour in others as the development of each region in which the fibres grow proceeds.The medullated fibres appeared in greatest quantities in the later developing regions, except the belly which presents few medullated fibres.The staple is much finer at the first month of growth than in the later stages. Frequency curves of fibre size are of more value than average fibre size in estimating the value of the fleece.3. It is suggested that the examination of the fleece of the lamb will give some idea of its genetic constitution and will reveal defects which would be concealed in the adult. Such a “phaeno-genetic” selection can be made best in a “late developing” area of the body such as the tail of the lamb at one month old.

Description: 1. From an analysis of the records from 702 cattle of predominating Jersey type tested for at least six consecutive years under normal and average herd conditions in New Zealand, the authors have attempted a detailed study of the nature of the increase in production according to age.2. They are unable to find any evidence supporting the theory that increase in production for dairy cattle operates as a percentage addition from early age to maturity.3. The evidence secured from an analysis of 702 Jersey records of six consecutive lactations commencing at 2 years of age, strongly suggests that the increase in production according to age can be summarized neither by a percentage addition nor a constant addition alone, but is best represented by a regression formula of the nature X = aY + b, where X equals the maturity production and Y the immature production.4. The strict regression formula will probably change according to the interpretation of “maturity equivalent”, but in general its application should lose little of the simplicity of the ratio form of conversion.

Description: Critical estimations of the recovery of sulphur, when materials such as fodder and excreta were subjected to a number of analytical procedures. The only method in this series which resulted in consistently good estimations was one involving oxidation in compressed oxygen confined in an Emerson Calorimeter Bomb.

Description: In the spring of 1937 an experiment was conducted to test existing commercial facilities for the transport of bull semen between England and Holland. Samples were sent to and received from Holland via Royal Dutch Air Lines, to whom the authors wish to express their sincere thanks for most useful co-operation. The minimum interval between collection in one country and insemination in the other was 28 hr. and the maximum, 57 hr.

Description: 1. The high grain-yielding capacity and low total nitrogen content of predominant British varieties of barley, in conjunction with high ear survival at harvest, are discussed.2. The results of a series of quantitative comparisons in which increased tillering was promoted by the application of nitrate of soda at various phases of plant development, and similarly when tillers were removed at various stages, were examined.3. It was shown that the effect of nitrogen on the yield and quality of the grain depends upon the time in relation to the stage of plant development at which it was applied; the early applications enhanced the yield without detriment to the quality of the grain, whilst the later applications did not increase the yield but increased the total nitrogen content, and consequently reduced the malting quality of the grain.4. The increase in yield was obtained primarily by an increase in the number of surviving tillers and to a less extent by an increase in yield of grain per ear; the latter was in some cases accompanied by an increase in 1000-grain weight. High ear survival in varieties such as those under examination may consequently be regarded as an index of high yield of grain and of low total nitrogen content.5. The removal of tillers resulted in increased total nitrogen content and increased 1000-grain weight in the grain of the main stem; the former was not affected by the stage of development of the plant at which abscission was made, but the highest value of the latter was obtained when the abscission was made before flowering.6. The relation of 1000-grain weight and nitrogen content was discussed, and it was shown that high 1000-grain weight may exist with both high and low total nitrogen. Although the 1000-grain weight is an hereditary attribute it is subject to considerable fluctuation and cannot by itself be usefully employed as an index of nitrogen content, and consequently of malting quality, in either an inter- or intra-varietal sense.

Description: 1. The vitamin A content of the colostrum of one hundred cows, kept under the same conditions of dietary and management, was found to range from 1181 to 35 I.U. per 100 ml.2. It has been established that this wide range was not due to any differences in dietary, breed or date of calving in animals kept under the same conditions of management.3. It is suggested that the vitamin A content of the colostrum may be materially affected by the length of the non-lactating period between successive calvings.

Description: The method suggested by Papadakis of using covariance with the yields of neighbouring plots to reduce the error of replicated field experiments is illustrated on two large-scale cotton experiments. In a discussion on the validity and value of the method, it is concluded that for such experiments, where the number of plots per block is large, the method should be approximately valid and sometimes useful.

Description: An account of the agricultural conditions which influence the development of stem-end blackening in cooked potatoes has recently been given (Wager, 1946). The evidence given by Smith, Nash & Dittman (1942) shows that the average air temperature for the three weeks preceding the lifting of the tubers, or the death of the tops, controls the development of stem-end blackening in the tubers and the authors claim that this is an overriding factor. In their experiments, extending over several years, little or no blackening developed when the average air temperature was between 70 and 80° F., when between 60 and 70° F. there was a medium development of blackening and when between 50 and 60° F. there was much blackening.

Description: In this paper are presented the results of an investigation into the composition and digestibility of fodder cellulose. This product was manufactured from wheat straw by the method employed in the making of paper. Wheat straw was boiled with 5·9% caustic soda solution for 7 hr. under a pressure of 70 lb./sq.in. The alkaline liquor was then run off, and the residual cellulose, after being washed with water until free from alkali, was pressed, dried in electric ovens at 100° C. and finally obtained in the form of a coarse meal. It contained, on the basis of dry matter, 79·82% of crude fibre, 16·22% of N-free extractives (mainly xylan), 0·36% of crude protein, 0·49% of other extract and 3·11% of ash. Its content of total cellulose (‘true’ cellulose plus associated cellulosan, as defined by Norman & Jenkins, 1933) amounted to 97·4% on the moisture and ash-free basis.Digestion trials were carried out with both sheep and pigs. The daily ration of the sheep consisted of 800 g. of chaffed meadow hay, 600 g. of fodder cellulose, 100 g. of linseed cake, 60 g. of molasses and 18 g. of a mixture of equal parts of common salt and precipitated tricalcic phosphate. Although the fodder cellulose formed as much as 38% of the total daily food, no difficulty was experienced in securing clean and ready consumption.

Description: 1. Treatment of seed beans with an organomercurial dressing has been shown to have little or no effect on growth and yield.2. Experiments have shown that the emergence of ‘weevilled’ beans is markedly less than that of sound beans for both winter and spring sowings.3. It is suggested that the reduced emergence of weevilled beans is due to beetle injury of the seed and not to invasion by soil organisms.

Description: The purpose of this note is to present the results of the analysis of a series of experiments for the existence of interactions between treatments tested and blocks. It is implicit in all modern designs which involve confounding and/or fractional replication that such interactions are negligible compared with the effects and interactions which the experiments are designed to estimate. The matter has been discussed from the theoretical point of view in a recent paper on confounding and fractional replication (Kempthorne, 1947). This note will consist of a short statement of the problem and the results of an examination of a series of experiments on sugar beet which provide information on the point in question.

Description: 1. One laying and one non-laying bird were fed a normal calcium ration, and one laying and one non-laying bird were fed a low calcium ration. Four hours after feeding the birds were killed, and the contents of the various portions of the alimentary tract were analysed and compared with the composition of the original food.2. The pH of the crop contents is influenced by the pH of the food. The lowest pH value is given by the gizzard contents, but after that there is a gradual rise, until, by the time the 4th segment of the small intestine is reached, the pH. is almost constant at about 6·8 for all birds.

Description: There was a significant positive correlation between the buffer capacity and motility of sperm and a highly significant negative correlation between the buffer capacity and the pH. There was no correlation between the buffer capacity and the volume of the ejaculate or the number of sperm per c.mm. Specimens which maintained a good motility on storage had a better buffer capacity than those which did not.The specific gravity of 125 semen specimens was 1·0337. There was a highly significant positive correlation between the specific gravity and the number of sperm per c.mm. and the percentage motility and a highly significant negative correlation between the specific gravity and the pH. There was no relationship between the specific gravity of semen and the volume of the ejaculate, or the pH change. In general, the higher the specific gravity of the seminal fluid, the better was motility maintained on storage. The higher the specific gravity, the lower was the pH and the better the buffer capacity of seminal fluid.

Description: Consideration of the composition of pig depot fats from the point of view of Callow's growth-rate theory (Callow, 1935a,b), shows that the theory appears to explain the iodine values of fats both of groups of animals and of depots of an individual pig. When, however, the fatty acid compositions of the fats are considered, the theory is untenable in respect of the depots of an individual pig. Differences in unsaturation between outer back fat, inner back fat, and perinephric fat are essentially determined by differences in the ratio of oleic acid to stearic acid, differences in linoleic acid content being inconsiderable.It can equally be shown that the growth-rate theory does not explain the results obtained by Hilditch & Pedelty (1941) for depot fats of sheep. Differences between different depots both of the pig and of the sheep seem to be characteristic of the species and cannot readily be altered by altering either the quantity or the quality of the diet.

Description: The wartime expansion in the home production of grass, clover and other seeds raised the question of the value of such seeds as food for livestock, since during the later years of the war, surpluses that had been discarded on account of low germination or other causes were being sold to compound manufacturers for inclusion in cattle foods. During 1944, the writers made determinations of the digestibility and starch equivalents of the following seeds: ryegrass (a mixture of Italian and Perennial), red clover, lucerne and un-milled sainfoin. All the samples were reduced to a fine meal before being submitted to test in the digestion trials.Apart from its lower content of digestible ether extract, ryegrass-seed meal resembles oats in respect of chemical composition, digestibility and starch equivalent. It is a carbohydrate concentrate, containing, on the dry matter basis, 69·4% of starch equivalent, including 7·3% of digestible protein.

Description: 1. For experimental purposes the treatment of cotton seed with sulphuric acid, prior to planting, has always been the custom at Barberton. In view of the doubts about the benefits of this treatment which were expressed by Christidis (1936), experiments were carried out at Barberton in the 1938–9 and 1939–40 seasons, to provide concrete proof, if possible, of the advantages which it was believed resulted from it.2. A series of stand counts made soon after germination revealed definite benefits with acid treatment, in all experiments in both seasons. The seedlings emerged considerably earlier than those from untreated seeds, and the stands recorded at the final counts revealed a significant advantage for acid-treated seed, throughout the experiments. The second season's experiments gave a greater advantage for acid treating when meteorological conditions were bad than when they were good, but the advantage even with ideal weather was still significant. The benefit of acid treatment was shown to be greater, too, with poor samples of seed than with good, and with the smaller seed rate than with the greater.

Description: 1. The effect of low-temperature and continuous-light treatment of seedlings of certain sugar beet strains in the isolation of distinct physiological types is described. The progenies of individual plants and bulk samples of different anthesis dates show some difference in the proportions of early and late plants, when these progenies are similarly exposed to low temperatures and continuous light in the seedling.2. Different treatments of progenies in relation to light treatment in the seedling stage result in distinct behaviour with regard to anthesis date and the number of plants reaching the stage of anthesis.3. The comparative resistance to bolting from a field sowing of seed obtained from plants which ripened seed after continuous light treatment of the seedlings is noted. This was so in spite of the fact that only 66% of the plants had reached anthesis as a result of the treatment, and the seed was obtained from the most rapidly bolting plants.4. Light and low temperature exposure of seedlings is effective in two different strains for isolating bolting-resistant types as measured directly from the seed of these bolting-resistant plants and selected progenies from these plants. Differences in the field germination and establishment from very early sowings were discernible in the progenies.

Description: Much work has been done with regard to the elements necessary for plants, their function in the plant, methods of absorption, amounts necessary, nutrient solutions, etc. The following is particularly, concerned with nutrient solutions, including their composition, concentration, methods of application, and the general methods of dealing with sand and water cultures. The work is confined mainly to a study of the major elements.

Description: In the breeding of animals like cattle which reproduce slowly relative to the working life of a breeder, time is a factor of major importance. A study has therefore been made of the duration of samples of pedigree herds in order to obtain some indication of the time actually spent by breeders in the selective breeding of dairy cattle.The samples consisted of pedigree Ayrshire, Jersey and Shorthorn herds, (a) established at various fixed times in the past; and (b) existing in 1939. The former were traced forwards, and the latter backwards, by means of herdbook registrations. Each sample contained not less than 300 herds, and the distribution of durations in each was considered in relation to the movement of population numbers in the whole breeds from which they were drawn.

Description: The low temperature ignition of soil organic matter has been investigated for temperatures ranging from 100 to 500° C.Appreciable losses are found to occur below 100° C.; up to 200° C. heating results essentially in the distillation of volatile constituents, while between this temperature and 300° C. destructive distillation is the major reaction. These reactions are responsible for the removal of 85% of the soil organic matter.By 300° C. the greater part of the residual organic matter consists of carbonaceous material, and the final reaction is simple ignition of this material.Two hours’ heating of the soil at 450° C. or about half an hour at 500° C. are recommended for the removal of 99% of the soil organic matter.

Description: 1. Wheat, barley or mangolds gave nearly the same yield if grown on seed beds prepared by ploughing and harrowing, by using the grubber or cultivator and harrowing and by using the Rototiller, provided that the cultivators were used for one year only. If used for several years in succession deterioration of yield sometimes sets in, possibly due to the increased weediness of the non-ploughed plots.2. There was no advantage in ploughing deeper than 4 in. but it is advantageous to use the grubber of Rototiller deeper.3. The effect of cross-ploughing, subsoiling or heavy rolling the seed bed for spring-sown crops was without effect on the yield.4. Spring rolling and harrowing improved the yield of winter wheat but had little effect on the yield of straw. Rolling alone may have produced a slightly increased yield of grain but it improved the straw yield while harrowing depressed the straw yield.5. There was strong evidence that intensive hoeing of sugar-beet or kale is detrimental. Two to three hoeings appear to be ample.

Description: 1. The principal change in the composition of adult fowls during fattening is an increase in the fat content of the body, the protein increase being subordinate in amount.2. Within the limits studied, the efficiency of conversion of food energy to carcase energy is not affected by variation in the protein content of the ration.3. A food mixture consisting of 5% dried skim milk of 95% Sussex ground oats proved as efficient for fattening fowls as a food mixture consisting of 20% dried skim milk, and 80% Sussex ground oats.4. The food mixtures used gave satisfactory results in fattening when used in pellet form in a dry state.

Description: 1. Experiments are described in which the riboflavin contents of the liver, kidney, heart and leg muscles of chicks were assayed during the first few weeks after hatching, using birds reared on both riboflavin-deficient and riboflavin-adequate diets.2. Changes in the composition of the liver during the first 3 weeks after hatching have been studied.3. At hatching, half the chick's liver consists of oil; this proportion is maintained during the first week, but falls to about one-eighth during the second week and maintains this level during the third week.4. When birds are reared on a riboflavin-deficient diet, the riboflavin concentrations of the heart and kidney are reduced more rapidly than that of the leg muscles.

Description: SUMMARYA method is described for economizing in the use of fertilizers on deficient soil by soaking the cereal seeds in nutrient solutions containing the deficient element at a sufficiently high concentration to supply a large part of the total requirements of the plants.The result of greatest potential practical importance was obtained on oats. Soaking oats in molecular tribasic potassium phosphate brought about an increase in yield from 17 to 25 cwt./acre (46 %) on phosphate-deficient soil at the cost of 13·6 lb./acre of the potassium phosphate (or 4·6 lb. P2O6) without the addition of any phosphate to the soil. There was a correspondingly large increase in the weight of straw. Nearly 75% of the P2O5 introduced in this way was recovered from the harvested grain. Sodium phosphate appears equally efficaceous for oats. Strikingly beneficial effects were also obtained on barley and wheat.

Description: The apparatus is a simplification and an improvement on one devised by the author for the study of soil metabolism (Lees & Quastel, 1944) Its function is to percolate a column of sieved soil automatically and regularly with small quantities of a well-aerated solution of metabolites and to return the percolated solution, now modified by the activities of the soil microflora, to the reservoir whence it came As this circulatory process is continuous, metabolic activities in the soil are reflected as chemical changes in the reservoir solution and can be followed by analyses of it.

Description: The influence of rainfall during the growing season on the yield of the Park Grass plots at Rothamsted, which are cut for hay every year, has been investigated.The average yields in the period 1858–1902 on the thirteen plots examined were from 18 cwt./acre on an unmanured plot to 61 cwt./acre on a plot receiving a complete fertilizer including a heavy dressing of nitrogen. All the plots showed some deterioration in yield. The effect of the total amount of rainfall from 5 March to 8 July was very substantial on all plots, the average increase in yield for each additional inch of rain varying between 0·7 and 2·4 cwt./acre; the benefit was greatest on the plots dressed with sulphate of ammonia. The rainfall effects reached a maximum in the latter part of April and early May, but the distribution of the rain appeared to be of relatively small importance.

Description: 1. An experiment was performed to compare some methods of supplying calcium to intensively kept chickens.2. The calcium content of a mash was adjusted to contain low (0·13%), normal (1·16%) and high (2·14%) amounts, and each of these mashes was fed to groups of chicks having access to: (a) no grit, (b) flint grit alone, (c) limestone grit alone, (d) both flint and limestone grit.3. The addition of flint grit significantly improved the efficiency of food utilization on all diets, whether limestone grit was provided or not.4. On all three mashes the total amount of calcium grit consumed was greater in the presence of flint grit than when it was fed alone.5. As the level of calcium in the diet increased, the amount of limestone grit consumed decreased, whether it was fed alone or in the presence of flint grit.6. The best results, judged on a live-weight basis, were obtained when the normal calcium mash was fed with flint grit alone, followed by the low calcium mash with both flint and limestone grit, followed by the normal calcium mash with no grit.7. On the basis of the efficiency of food utilization, the low calcium diet with flint and limestone grit was best followed by the normal calcium diet with flint grit alone.8. Access to limestone grit reduced the efficiency of food utilization in all but the low calcium diet.

Description: Samples of potatoes were collected in three successive seasons from a wide range of soil types and their liability to stem-end blackening determined.Variety and season of growth affected the amount of stem-end blackening which developed.All soil types gave samples with a wide range of stem-end blackening, but the average amounts of blackening in samples from different soil types were shown to differ significantly. Samples from fen, blackland, sand, gravel, limestone and chalk blackened more than those from skirt, silt, warp, clay and boulder clay.The pH of the expressed sap of tubers was independent of the type of soil in which they were grown, but dependent on variety and locality of growth. No evidence that the pH of the tubers influenced the amount of stem-end blackening pigment was obtained.The yellowness of the flesh of tubers showed an approximately normal distribution. Slight evidence for an effect of soil type on the amount of yellow pigment was obtained.The work described above was carried out as part of the programme of the Food Investigation Board of the Department of Scientific and Industrial Research.

Description: The copper, iron and lead contents were determined on an age series of foetal livers obtained during the latter half of pregnancy from normal ewes at Cambridge. The total amounts of the metals showed a rapid rise during the last 3 weeks of gestation due to an increase in the size of the organ and in the actual concentrations. Towards full term and in the new-born animal the results showed an increasing variation which even extended to twins. It is noted that foetal transference takes place without affecting the blood copper of the ewe or causing a physiological anaemia of pregnancy. The time at which the process is at its height is correlated with experience in the prophylaxis of swayback. It is estimated that the store of copper at birth may tide the lamb through the suckling period but the store of iron requires to be supplemented by the diet and that the ewe's milk may make a significant contribution towards this. The small amounts of lead found were of the same order as reported for normal humans and in swayback lambs in Derbyshire; hence the latter cannot be regarded as abnormal.

Description: 1. Experience raised doubts as to the usefulness of filling gaps in bad stands of cotton at Barberton and experiments were conducted in two seasons to measure its effectiveness. The experiments gave clear-cut results.2. Randomized gaps ranging from 20 to 40% of the stand were filled and left open for comparison, the filling being done 13 and 19 days after planting.3. Any reduction in stand, though reducing yield per acre, led to large and significant increases in yield per plant, even when the spacing was 3 by 3 ft., wider than that normally used on the Station.4. Replanting the gaps in a bad stand did not lead to any increase in yield per acre; there were, in fact, indications that this practice actually reduced yield per acre, the refills preventing plants of the original sowing from benefiting fully from the extra space available to them in a bad stand.5. The general conclusion is that no useful purpose is served by refilling the gaps in poor stands of cotton with up to 40% of gaps.

Description: The wool production of a small flock of Romney Sheep has been studied for a few years. When the sheep were 1 month old squares were tattooed on to four regions of each sheep.The weight of wool from, and the area of, these squares has been studied.We find that, under good growing conditions, for the same region, all sheep produce the same weight of wool per sq.cm. of skin per day (denoted by c), which is independent of age, seasons, year of birth of sheep, but varies from region to region, being higher the nearer the region to the mid-dorsal line.When conditions are unfavourable the weight of wool a particular sheep produces from a particular region falls below the c value for the region, approximately, by a factor (1 – B/E), where E is the skin expansion ratio of the particular region and B is a number, the same for all sheep and all regions in one season and is greater the worse the season.I am particularly indebted to Dr Hammond, School of Agriculture, Cambridge, and to Mr W. S. Kelly (Australia) for help and advice, and to the Animal Research Station, Cambridge, for providing the facilities for working with sheep. I wish to express my indebtedness to my colleagues of the Biology Department of this Association who have assisted me in various ways, and to Dr Daniels for help with the statistical treatment of the data, and to Mr R. C. Palmer for criticism and help in preparing the results for publication. My thanks are due to Mr B. H. Wilsdon, Director of Research, for his encouragement, to the International Wool Secretariat for providing the sheep, and to the Council of the Wool Industries Research Association for permission to publish the results.

Description: 1. A manometric technique for the assessment of soil aeration, described in a preceding paper by Webley (1947), has been used for comparing the effects of the incorporation into soil of alginic acid (as the ion) and other organic materials on soil airwater relationships. Some of the shortcomings of the technique, as well as its advantages are described.2. The addition of sodium alginate to a soil improves its crumb stability and its water-holding power. It is shown that the addition of 0-1 g. sodium alginate to 100 g. of the air-dried standard soil used in this work has a gross effect equivalent to an increase in the water-holding power of soil of 11%. The effect of the alginate rapidly increases to a maximum with increase of the concentration of the alginate. The incorporation of the relatively insoluble calcium alginate has but little effect on the soil airwater relationship. It is suggested that alginate confers hydrophilic properties on soil by its combination as an ion with one or more constituents of the soil particle, thereby presenting new surfaces with high water-holding powers.3. Incorporation into soil of cellulose acetate, methyl cellulose or of carboxymethyl cellulose improves its water-air relationships.

Description: SUMMARY1. The results of a study of sampling for ginning percentage in cotton variety trials are given. The investigation was undertaken to determine the most satisfactory method of obtaining the necessary ginning percentage factors for conversion of yield of seed-cotton to yield of lint.2. The material consisted of a widerange of strains derived from the jassid-resistant Upland, U4, planted out in trials of randomized block design, in different seasons.

Description: SUMMARYThe loss of viability of seeds of Chewing's Fescue Grass has been a serious problem to both the producers in New Zealand and the trade in the United Kingdom. It has been shown by Foy (1934) that seeds with a high moisture content (20 %) held at 30° C. deteriorated rapidly after 10–14 days and even more quickly at 40° and 50° C. Seeds with a water content of 13 % deteriorated more slowly but it was not until the water content was reduced to and maintained at 5 % that seeds retained their viability at 30°, 40° or 50° C. for 42 days. Even at room temperature (16–20° C.) the loss of viability occurred after 4–5 months at 20 % water content and after 8–9 months at 13 % but at 5 % water content there was no loss. Foy discusses the effects of temperature and humidity that may occur during transport; Hyde (1935) has examined the effect of heating seeds to 50°, 60°, 70°, 80° and 90° C. with a view to working out the conditions for artificial drying of the seeds before transport, and Lewis (1934) has found that, in some seasons, there was a marked loss of viability in storing these seeds in the United Kingdom.

Description: SUMMARY1. Sexually immature White Wyandotte pullets have been treated with gonadal hormones with the object of simulating those changes in calcium and phosphorus metabolism which normally take place during the fortnight or so before laying begins.2. It is shown that certain treatments of the sexually immature pullet with oestradiol dipropionate evoked hypertrophy of the oviduct and changes in blood calcium and phosphorus similar to those encountered in the normal laying pullet, but did not produce any significant increase in the rate of calcium or phosphorus retention.

Description: 1. A series of experiments was carried out to assess the importance of the sense of smell to the grazing sheep.2. The results of the first two experiments described indicated that the sense of smell is of importance in the initial stimulation of appetite, but under the experimental conditions the selection of particular herbage species was not affected.3. Further experimentation showed that, because of its adaptation character, olfaction can only be of supplementary importance in influencing the food selection of the grazing sheep.

Description: SUMMARY1. The physiological effects of severe hyperthyroidism on five sheep are described.2. Increases in pulse rate of more than 100% were observed. The increase in pulse rate was proportional to dosage with the exception of one sheep which had lesions on the chordae tendinae of the left ventricle.3. The heart, even though beating at this elevated rate, reacted normally to severe exercise, but there was a tendency for the sheep to carry out its normal functions at a slower rate so such large increases in pulse rate did not occur as the result of voluntary activity.4. Considerable cardiac arrhythmia was noticed in all hyperthyroid sheep.5. The relative increases in pulse rate of the cow and the sheep given iodinated casein of the same potency suggest that as between species dosage of iodinated casein is proportional to ‘metabolic body size’—the between species unit of basal metabolism—rather than to body weight itself. On this basis the stimulation of the sheep was between 1 and 4 times the dosage accepted as normal for the cow.6. Body temperatures increased in the most severely affected animals. Respiratory rates quadrupled in some cases.

Description: SUMMARYIn the investigation described, we have observed a t monthly intervals throughout gestation the changes taking place in a series of similar ewes, in lamb to the same ram, and each receiving the same standard diet.In following the live-weight growth curves of the ewes it was found that on a constant level of feeding the weight gains became greater during each succeeding month of pregnancy, and at corresponding stages were larger for ditocous than for monotocous ewes. This was found to be due to the fact that, although on our diet the ewes did gain slightly in actual body weight, the main increases in live weight resulted from the growth of the gravid uterus itself, and this increases in weight far more rapidly in the later stages of gestation, and is also heavier where twins are carried.

Description: SUMMARYComparative digestibility trials have been carried out on hays top-dressed with nitrogenous fertilizers 8–13 days before cutting and on similar hays which were not top-dressed.The top-dressing resulted in an increase of 2·0% crude protein and 1·2% true protein.The digestibility of the protein was significantly higher in the top-dressed hays and no other constituents were affected.The protein equivalents in hay dry matter were increased from 4·4 to 6·0% by the top-dressing.

Description: The Journal of Agricultural ScienceVol. 38, Part 3July 1948Page 323Fructose Content and Fructolysis in Semen. Practical Application in The Evaluation of Semen QualityBy T. Mann, Molteno Institute, University of CambridgeThe last sentence on p. 323 at present reads as follows: “0.25M phosphate buffer pH 7.4, prepared by dissolving Na2HPO4 (or Na2HPO4. 12H2O) in 190 ml. glass distilled water and adding 10 ml. IN-HCI.”

Description: SUMMARYEvidence is provided to prove that the nutritional malady, Coast Disease, which affects sheep de-pastured without change on the shell-sand littoral of South Australia is due solely to the inability of the pastures to provide the quantity of cobalt and copper necessary to fulfil the nutritional requirements of grazing sheep.An experiment started in 1936 in which five evenly matched groups of young cross-bred ewe hoggets were dosed thrice weekly with cobalt, copper, cobalt plus copper, and with cobalt plus copper together with iron, manganese, zinc and nickel is described.

Description: A statistical experiment was made on May King lettuce grown in a gravel soil in the unheated greenhouse to ascertain the effect of periodic sowings, two levels of water, and alternate drought and saturation with water on bolting and growth.Mature lettuces at a low level of water were darker than those at a high level. The total numbers bolting irrespective of treatment were highest in May to July, and this period coincided with temperatures above 60° F., long days, and decreasing ages from germination to bolting; the largest lettuces were harvested in October to May (excluding mid-January to late March), a period of low temperatures less than 60° F., short days, and increasing ages from germination to harvest.

Description: An outline is given of an investigation that has dealt with disinfectant dusts containing mercury, and it is shown that the majority of the inorganic mercury salts are of little value in this respect. Some organic mercury salts have been tested and the result of laboratory and field work suggests that there is a close relationship between composition and fungicidal power. In the series R-Hg-X, where R is a hydrocarbon and X an acidic radicle, the fungicidal power appears to decrease with the increase of the molecule of R. A study is made of the significance of X in the methyl series and the results as they apply to disease control are recorded on a series of graphs.The specificity of some of the compounds is noted and a brief mention is made of the treatment of seeds other than cereals.It is suggested that there is no evidence for stimulation in the sense of tonic effect but that instances of better germination, growth and crop yields are due not only to the control of seed-borne organisms but to the preservation of the food reserves in the seed from the attack of soil organisms or mould organisms adherent to the seed.

Description: 1. The details of the Dennstedt dry-combustion method for determining carbon in soils were described, and some simplifications suggested.2. The Bangor modified Kjeldahl method for carbon and nitrogen in soils requires carefully standardised heating. Errors may arise from contamination of sandy soils by material abraded during grinding in iron or porcelain mills.3. For many heavy soils the addition of water before the Kjeldahl digestion is convenient but not essential. For heavy alkaline soils with little organic matter it is advisable to grind the soil very finely and to add water.

Description: 1. A reliable identification of grain samples of related wheat varieties of different grain values is of economic importance.2. The distensometer test distinguishes with a high degree of reliability between Tuscan and Cross 7 grain, whereas eye inspection, baking and fermentation tests cannot be relied upon for differentiation between the two varieties.3. A testing service for the use of farmers, grain merchants and millers would involve no technical difficulties.

Description: The task of wheat growing in New Zealand is limited to providing for the needs of a population of 1½ million. Owing to the long distance from other wheat-growing countries it is considered essential for the Dominion to remain independent in its supply of wheat and flour. A sliding scale duty fixes the price of wheat at a level sufficiently remunerative to the grower to insure the production of approximately the required amount. Since 1927, when this duty was introduced, the area under wheat has varied between 236,000 and 302,000 acres, and the annual production between 6½ and 11 million bushels. The requirements for flour milling, seed and stock food being slightly less than 9 million bushels, shortages due to unfavourable seasons are covered by the carry-over from the previous season, and/or by importation. It is only in seasons of excessive yields that export of wheat becomes necessary. Under the compulsory pooling system in force since 1932·3, losses due to the difference between local and export prices are distributed amongst all the wheat growers in the Dominion.

Description: Fat colour is of importance in beef produced for English markets because of discrimination against deep yellow fat. The factors at present known to affect colour are genetic(1,4) and those relating to food supply(2,3), but not much is yet known of the various circumstances or natural conditions under which the colour will vary in shade. It was the purpose of this investigation to determine some of these. Rabbits were selected for the preliminary experiments, as, although it is questionable whether the colouring matter in the fat is quite the same as in cattle (3, 5), it is very probably affected by the same conditions. Experiments could be done quicker and cheaper in rabbits than in cattle on which the results could be tested after the pioneer work in the rabbit was completed.

Description: 1. Attention is drawn to the remarkable dissimilarity between the cacao and the grapefruit tree in their nutrient requirements, indicating that grapefruit is calcicolous in physiological habit. This conclusion is mainly based on a consideration of the results of chemical analysis of representative leaf material produced by trees grown on soil of known chemical and physical characteristics, under the same climatic conditions in Trinidad.2. The nutrient relationships that obtain between the cacao and the grapefruit tree respectively and the soil in which they are growing have been gauged by means of chemical analysis of representative leaf material.3. For this purpose, leaf material was obtained from trees growing on the differently manured plots of two large-scale field experiments in Trinidad.

Description: In this paper are brought together a number of data concerning the ratio of the amount of leaf to stem in the lucerne crop, at different stages of growth, and the separate composition of the leafy and stemmy fractions.It is shown that the proportion of leaf falls off as the crop advances in maturity, and that the rate of decrease of leafiness is greater before budding than during the period from the beginning of budding to early flower. The changes in the leaf-stem ratio largely account for the fall in protein content, the rise in fibre content and the running-off in digestibility and feeding value that take place as the crop passes through the successive stages of growth up to flowering.

Description: The variations in sticky point of homionic soils as determined by kneading with electrolytic solutions have been examined. In the case of sodium soils, a well-marked maximum has been found in the sticky-point/electrolytic concentration curve; and the form of the curve shows parallelism with the extent of flocculation produced by varying electrolytic concentrations.

Description: The study of the effect of rainfall on the yields of wheat from the continuous experiments on Broadbalk, Rothamsted, gave clear evidence of a close relation between the response in yield to rainfall and the manurial treatment of the soil. In later investigations of a similar nature on barley at Rothamsted and on wheat and barley at Woburn, however, the evidence did not point to a significant effect of rainfall on yields, and on this account little can be said with confidence from these investigations. The present note shows that the relation between seasonal variations in yield and manurial treatment is just as clear at Woburn as on Broadbalk, the difference between the two centres being that similar studies on rainfall effects have had more definite and successful results on Broadbalk. At Woburn, indeed, little progress has been made towards elucidating the particular weather factors whose quantitative influence is important.

Description: V. SummaryFor the purpose of describing the development of the Romney lambs’ coats it was found convenient to divide the skin into six areas, A, B, C, D, E and F, each being formed by the grouping of all regions that develop at the same time and rate.These areas are determined by the following methods:1. All regions where X and Y follicles begin growth at the same time belong to the same area.2. All regions attaining the trio stage of development at the same time belong to the same area.

Description: The estimation of the experimental yields of cereal crops by sampling methods is considered in the light of results of eighteen experiments which were harvested by these methods at Rothamsted and its associated centres. The harvesting results of the Crop-Weather series of experiments are also included.A preliminary discussion of the interpretation of the analysis of variance as applied to sampling results is given, and an expression is found for the loss of information arising out of sampling. The results of the discussion are applicable to all types of sampling carried out on replicated experiments.The sampling and experimental errors of all the experiments have been calculated. The variation between sampling units in the same subplot (usually between l/100th and l/200th acre) was found to be such as would arise if each metre length of row had a standard deviation (about the plot mean) of the order of 25–30 per cent. of the mean yield.

Description: The crude-fibre determination is misleading, because the fraction obtained does not bear any definite relationship to the structural constituents of the material. The cellulose is partially attacked, and lignin extensively removed. Considerable variation is found in the lignin content of crude-fibre fractions. Highly lignified materials do not necessarily yield a crude fibre high in lignin.Since the presence of lignin exercises a direct effect on the digestibility of the material, any empirical method should include all the lignin, and alkaline treatment must be avoided. Acid hydrolysis may be a possible alternative method, if a correction for protein be made in the case of materials high in nitrogen, and a determination of the lignin content made.

Description: In field experimentation the effects involved can often only be satisfactorily evaluated on the basis of dry matter yield. The size of plots usually renders the drying of the whole produce impracticable; this necessitates the determination of dry matter content by means of sampling. Since it is essential, on statistical grounds, that each plot should be separately sampled, an experiment may entail the determination of a large number of dry matter percentages. Agricultural produce is generally bulky and subject to fermentation, and therefore apparatus of a larger capacity than that usually found in laboratories is required. In the past much use has been made of uncovered gas heated hot plates, but these are unsatisfactory. Such hot plates do not lend themselves to accurate control of temperature, nor is uniformity of temperature over the plate easy to attain. It is therefore necessary either to run the risk of occasionally burning samples or to dry more slowly than is desirable. Hot plates are very wasteful of heat and the samples are unprotected during drying.

Description: Attention has been drawn to the remarkable growth rates obtained in certain litters of pigs under farm conditions.It has been pointed out that no explanation has been put forward to account for their occurrence.The literature relating to the new dietary factor, physin (Mapson), essential for optimum growth and reproduction in experimental rats, trout and dogs, has been reviewed.Experiments are reported in which rations, adequate as far as our present knowledge of essential dietary constituents goes, were fed to young growing swine. In each of three experiments, animals which received in addition 4 oz. of raw minced liver per day showed a 40 per cent. increase in growth rate compared with the controls.When food intake was controlled according to the new method of individual feeding, the liver animals showed the same gains in weight as the animals receiving the basal diet alone.

Description: The original object of the breeding investigations described above was to secure a new variety of oats exhibiting the resistance to winter conditions and the grain quality characteristic of Grey Winter, in combination, if possible, with straw of better standing power.The characters of the hybrids studied in the course of the investigations were accordingly resistance to winter conditions, standing power of the straw, quality of the grain, and the early growth habit, particularly in relation to these three features.

Description: 1. A soil moisture meter which gives direct and continuous measurement of the soil moisture content is described. The instrument consists of a special porous pot filled with water, connected by a tube to a mercury manometer. The pot is buried in the soil, whose capillary pull causes the mercury to rise. The height to which the mercury rises depends on the amount of moisture in the soil, and also on the size of soil particles and the degree of compactness of the soil. (The last two factors remain constant for an instrument in one position.)2. To read actual moisture percentage each instrument has to be calibrated for the soil in which it is placed. Once this is done, all sampling and weighing is eliminated.

Description: XII. SummaryThe experiment was designed to compare under Trinidad conditions three varieties of fodder grass and ascertain the correct stage at which each should be cut to give the maximum nutritive value per acre. It consisted of a yield trial in the form of a Latin square in which the treatment series included four cutting rotations on main plots and three varieties of fodder grass on subplots as appended

Description: 1. Exp. I was conducted with two pigs in each group, which pigs were kept during certain times in digestion boxes, permitting the separate collection of faeces and urine.2. The total amount of food given to the pigs was slightly below the present standards.3. The different rations contained different amounts of protein and different amounts of non-nitrogenous constituents.4. Exp. II was conducted with one pig in each group and served to control and supplement the data collected in the previous experiment.

Description: 1. New and old seed beans have been compared for three years, in the last two of which precise field experiments have been conducted with two different strains.2. In general new seed gave higher yields than old seed, but the difference was only of the order of 10 per cent. There was some evidence that conditions when the seed was harvested might be more important than age.3. New seed produced more branches in early spring, and a greater number of pod-bearing stems at harvest; on the other hand, old seed produced stems that were more thickly podded at harvest, and pods that contained a greater number of beans.4. In one case abnormally large seed produced very vigorous plants, and very large beans at harvest.

Description: The exposure of turkey eggs during the latter part of incubation, to temperatures (uniform around the egg) ranging from 30–5 to 41–5° C, in intervals of one degree, showed that:1. The hatchability was best at temperatures of from 36 to 38° C.; then it declined with a greater slope towards high than towards low temperature.(2) The time of hatching was progressively delayed, from 1 to 3 days, towards high and low temperatures.(3) The weight of birds at hatching from eggs exposed to various temperatures was fairly uniform.

Description: The cause of variation in the live-weight increase of animals on experiment has been further investigated. It had been shown previously that varying food intakes and initial weights-inherent drawbacks of the group-feeding method-accounted for much of this variation. When these two factors are rigidly controlled small differences in live-weight gains are still obtained. Evidence is presented to show that the basal metabolism and the digestive capacity of animals are for all purposes the same, and cannot account for any great part of the residual variation.

Description: This study treats of the progress in the milk production of a cow during a single lactation, and the relation of this trend to various factors associated with the particular lactation. The analysis is based on the monthly milk production records of all cows having six or more lactations, in a single large herd of pure-bred Jerseys. The herd provided records on ninety-nine such cows having a total of 679 lactations. Since the trend in the amount of milk produced in a lactation may be described by a simple exponential curve, this equation was fitted to the first 8-months’ production records for each of the 679 lactations. From these curves, constants were obtained which measure for each lactation: the theoretical initial yield; the decline of milk yield with time, or in other words the persistency rate; and the scatter of the observed monthly yields about the smooth curve. It is these constants which were studied relative to certain general and biological factors.

Description: In this paper, which is the third of a series dealing with the nutritive properties of the lucerne crop, an account is given of the results of an investigation into the composition, digestibility and nutritive value of lucerne hay, lucerne meal and lucerne leaf meal.Three samples of lucerne hay were dealt with, the first two having been made by baling direct from the field and the third by the usual procedure of filling into the stack. It is shown that by baling from the field, it is possible to conserve forage at a higher moisture content than would be considered safe when filling the material into a stack. In such circumstances, however, too tight a compression of the bales should be avoided, since if the process of partial drying-out during storage be retarded by over-compression, there is danger of extensive mould development and spoiling. It is advisable that the bales should be stored under good cover and in such a manner as to permit of free circulation of air between them. The hay from the bales was of much poorer quality than that made in the stack.

Description: 1. The question whether the amount of cystine in the wool grown may exceed that in the diet is discussed.2. When 1 gm. of laevo-cystine was added to the daily ration of a ewe on a low protein diet, the wool grown upon a circumscribed area was 14 per cent, more than that grown during a similar period immediately preceding. Four-fifths of the sulphur in the added cystine was absorbed, about half of which was excreted in the urine during the period the cystine was being fed.3. When 1 gm. of laevo-cystein was injected subcutaneously each day for 10 days, a 34 per cent, increase in wool growth occurred. During three succeeding periods, of 10 days each, immediately after the injections had been discontinued, the increases were 30, 18 and 7 per cent, respectively. Of the 2.6 gm. of sulphur in the cystein injected during the 10 days, 1.7 gm. was retained and could be accounted for by the extra amount of wool grown during that and the succeeding periods.

Description: 1. During the fermentation of water-logged soil containing added substances with different carbon-nitrogen ratios, the reaction first turns slightly acid, but soon returns to the original hydrogen-ion concentration (pH 7·6).2. The quantities of ammonia present in the medium increase up to a point, after which there is steady decrease.3. There is nitrification only in the case of substances with narrow C/N ratios. The production of nitrate generally commences only after about a month, when the vigour of the initial fermentation has subsided and fairly large quantities of ammonia have accumulated in the medium.4. The extent of mineralisation of nitrogen is determined chiefly by the C/N ratio, though in the cases of substances like mahua and lantana the presence of other constituents may also influence the processes. The quantities of mineralised nitrogen present in the soil system generally tend to decrease after about two months.

Description: The effects of lime on five soils representative of types from northeast Scotland have been studied and different lime requirement methods compared.Laboratory analyses including mechanical and ultimate chemical analyses, pH, exchangeable cation and lime-requirement determinations were carried out on samples taken before and at two intervals of 6 months after the application of lime.In some cases the maximum effect of the lime applied occurs within 6 months, in others neutralization is continued during the second 6 months.The change in pH value varies, according to the soil type, from 0·5 to 1·0 pH units per ton of calcium oxide applied per acre.

Description: 1. Several authors have previously reported that the sulphuric acid treatment of the cotton seed resulted in: (a) earlier germination, (b) higher percentage of seeds germinating, (c) higher yield of seed cotton per acre, and (d) better and more uniform planting (this paper is not concerned with the disinfecting effect of this process).2. A series of experiments, both in the laboratory and under field conditions have been carried out to determine whether the above statements are in agreement with actual experimental data.3. In so far as the rate of germination is concerned, it was found that: (a) untreated seeds often show a smaller percentage of germination than seeds treated with sulphuric acid for various time-intervals, particularly when tested in the laboratory; (b) cotton seed treated with the reagent for from 5 min. to 2 hr. or even 5 hr. in some cases, does not show any decrease in its germinative value as determined by laboratory tests. In field trials seeds treated for 5 or 12 hr. practically do not germinate at all, whereas the 2 hr. treatment often shows a small decline in germination; (c) an enormous difference in the rate of germination has been revealed between the laboratory determinations on the one hand and the field determinations on the other.

Description: In recent years a number of workers have investigated the influence of nitrogenous fertilizers on the growth of pastures. In some cases they have claimed that such fertilizers lengthen the grazing season by producing grass earlier than normal in the spring, but no research has been carried out on the factors controlling this spring growth. Watson et al. (15) in a study of the influence of nitrogenous fertilizers on the seasons’ yield of rotationally grazed pasture at Jealott's Hill, showed that in 1 year ammonium sulphate applied at the rate of 23·2 lb. nitrogen per acre in March enabled the treated plots to be grazed some 14 days earlier than the control. Richardson(13) found that 44·8 lb. nitrogen per acre gave marked increases in yield. Woodman & Underwood(16), however, claimed that ammonium sulphate (14·5 lb. nitrogen per acre) produced no strikingly higher yields.

Description: The present practice of basing payment for bacon pigs not merely on carcass weight, but also on carcass quality as expressed in the factory grading results, has led necessarily to an enlargement of outook on the part of the investigator in the domain of swine nutrition. The interest of the experimenter in the past has tended to be restricted to such questions as the influence of nutritional factors on the rate of live-weight increase and the efficiency of food conversion, the problem of how feeding may influence carcass quality and conformation not having received the attention its importance merited.While the questions of the rate of growth and the efficiency, in terms of meal consumption, with which such growth is achieved are still matters of primary economic importance, it is realized that much more attention must be devoted than heretofore to the study of carcass quality and conformation in relation to feeding. In present circumstances, a nutritional investigation can scarcely be considered complete unless a substantial part of the research is carried out in the bacon factory following the slaughter of the experimental animals.