ALBERT

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 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from that in soils of other arid regions.I am indebted to H. Greene and E. M. Crowther for access to their earlier unpublished work on nitrification in Gezira soil, and to O. W. Snow of this Service for advice during the course of this work.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: 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: 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: 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: 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: A comparison of four methods for the determination of the exchangeable hydrogen content of soils was carried out on 157 soils, from twenty-one profiles and representative of four soil types.The methods employed were those of: (1) Hardy & Lewis, (2) Mehlich, (3) Bradfield & Allison, (4) Schofield.The best agreement was obtained between methods (2) and (3) which are also the simplest to apply.A positive correlation was found between low values given by method (1) and the organic matter content of the soil.

Description: 1. A method is described whereby absolute changes in the organic and mineral constituents of cacao leaves during decomposition may be followed.2. On a basis of their behaviour during decomposition, the components measured fall naturally into three groups. The first group comprises lignin, total protein, resistant protein, dilute-acid protein, concentrated-acid protein and nitrate-nitrogen; these exhibit an absolute increase during decompositión. The second group, represented by hemicelluloses, cellulose and pentosans, all show a downward trend, the decrease being most rapid at the outset. Alcohol- and ether-soluble substances constitute the third group and are characterized by a very rapid decrease during the first few weeks of decomposition.3. A large amount of material soluble in dilute acid which is neither protein nor reducing sugar is not accounted for; this on a carbon basis constitutes over 50% of the dilute acid hydrolysable fraction. The trend of this fraction is somewhat similar to the carbohydrate fractions. It is pointed out that this fraction should not be neglected in a proximate analysis of decomposing organic matter.4. Potassium exhibits a very rapid decrease at the onset of decomposition, and the trend is closely parallel to the alcohol- and ether-soluble substances. At times of heavy leaf fall there is consequently a marked manurial effect which may amount to the equivalent of 1 cwt. of sulphate of potash per acre.

Description: The bacterial syndrome encountered in epidemic bacillary white diarrhoea of chicks (pullorum disease) is initially one of invasion by faecal type organisms, this is followed by invasion by anaerogenic B. pullorum.Evidence is presented to show that ostensibly pure cultures of anaerogenic B. pullorum, consist of two organisms, a true aerogenic B. pullorum in symbiosis with an anaerobe, morphologically of the welchii type.Evidence is presented to show that variation in fermentation reactions of ostensibly pure cultures of anaerogenic B. pullorum depend upon the degree of symbiosis exerted between the anaerobe and the aerobe and this degree of symbiosis is greatly affected by methods of cultivation on solid media.It is proposed that the ovarian blight peculiar to adult hens which are carriers of bacillary white diarrhoea infection is caused by putrefaction of ovarian material in vivo by the activities of a morphologically welchii type organism.It is proposed that B. pullorum exists in one form only, namely, the aerogehic form, and that this organism is a potential pathogen only.

Description: A feeding test performed on Hanns Hall Farm chicks demonstrates that a diet conducive to intestinal putrefaction fed to chicks after 14 days from birth initiates an epidemic of bacillary white diarrhoea (pullorum disease).If is proposed that measures for the control of epidemic bacillary white diarrhoea of chicks (pullorum disease), which consist of the detection and removal of reacting hens from the flock by means of a diagnostic and sensitive antigen, cannot be effective unless accompanied by an alteration in nutrition for the purpose of reducing intestinal putrefaction.Experiments at this laboratory show that the agglutination test for bacillary white diarrhoea cannot differentiate between fowls which produce diseased chicks and fowls which produce chicks resistant to disease.Experiments at this laboratory show that B. pullorum as a potential pathogen does not remain viable to an extent that it is able to produce bacillary white diarrhoea in chicks from an incubator or brooder which has held diseased hatches or broods, respectively.

Description: Average lactation curves have been prepared from selected animals in a group of heifers treated for 60 or 100 days with stilboestrol or hexoestrol tablet implants. A treatment period of 100 days appears to give poorer results than one of 60 days. The optimum duration, on the average, is probably about 75 days, but seems to depend upon the way lactation develops—which bears no obvious relationship to the amount of oestrogen absorbed.A rise in yield follows tablet removal whether this is done while the yield is still rising or after it has begun to decline. Yield in an induced lactation may fall very far short of the animal's inherent capacity, but comparison between induced lactations and those at subsequent calvings shows that it may very nearly approach what would be a normal yield.A heifer which was treated twice did rather less well in her second induced lactation.Breeding histories of a number of implanted heifers are outlined. They were all animals which had failed previously to get in calf. 5–10% (without further treatment) did not return to an ovulatory cycle. About 70% of anatomically normal heifers got in calf, the service rate being about 2·6. A rather high incidence of abortions may be a feature of a recovery period from treatment, but may have been due to selection of animals with such a tendency.

Description: 1. By premature harvesting, as early as 5 days after fertilization, dwarf grains are obtained which will germinate readily and produce normal plants, even though grain size may be only 10% that of fully developed grain. Such plants tend to attain the same final size as those from mature grain. This paper deals with the growth under field conditions of dwarf grain with regard to survival during the winter, and final yield.2. Pot cultures with vernalized winter and spring varieties of rye, wheat, and barley have shown that the high growth rate characteristic of dwarf grain is not confined to the vegetative phase of growth, but is also manifested after the ear has developed. The fact emerges that dwarf grain can be successfully vernalized.3. A field trial is described using three size classes of grain (mature, medium, dwarf) with mean grain weights of 33·93, 23·56 and 10·23 mg. respectively. These were sown (i) at sowing rates of 2 and 3 bushels per acre, and (ii) at uniform spacings of approximately 200 and 300 grains per 9 ft. row. A subsidiary experiment with spacing of 1 ft. was also carried out.4. All classes of grain germinated well and survival during the winter was uniformly high in the equally spaced plots; with the close spacing of the dwarf grain at 2 and 3 bushels per acre (plots 11 and 12) percentage survival was somewhat reduced.5. The effect of grain size and spacing on time of flowering was negligible.

Description: 1. Experiments were made on the respiration of bran at different moisture levels using a continuous absorption apparatus in which the humidity of the air-stream was adjusted to be at equilibrium with the respiring bran. The rate of respiration was accelerated with increasing moisture content and was very rapid deterioration due to the high respiration rate and microbiological damage.2. Experiments were made on the storage of bran at known moisture contents in closed tins in the laboratory and also in sacks kept under farm conditions. The total nitrogen content of the bran stored in the tins appeared to increase during storage. From similar increases in total phosphorus, it is clear that the increase in total nitrogen was caused by a loss of dry matter from the stored feeding stuff, a fact which was further demonstrated by the loss in dry weight of the sacks of bran with attributed to two causes: (1) the respiration of the plant cells still active in the bran itself, and (2) the respiration of developing micro-organisms. It is evident from these experiments that fresh bran, free from insect infestation and stored at a moisture content of less than 13%, will have a very low respiration rate and will, therefore, not be liable to heating. Bran of 15–19% moisture content respires at a much faster rate and the time for which such material can be stored with freedom from heating or other types of deterioration will be limited.

Description: 1. Experiments were carried out to determine the period of survival of spermatozoa in the genital tract of the cow.2. No reliable results were obtained by searching, post-mortem, the genital tracts of two cows and three heifers killed at various intervals after insemination.3. An attempt to induce ovulation at a definite time to which insemination could be related, in order that the survival time of the spermatozoa might be determined by the recovery of the ova post-mortem, was not successful. Of four cows and one heifer given pregnant mare's serum followed by pregnancy urine, one ovulated. To one animal, where a large follicle was present in one ovary, pregnancy urine was given. Ovulation occurred but could not be definitely attributed to the pregnancy urine.

Description: 1. Losses of incorporated non-protein nitrogen compounds from stored cubes have been determined. The loss of incorporated urea was very small provided moulding did not occur. The loss of incorporated ammonium bicarbonate was large, amounting in all to some 50–60%.2. The effects of the size of the cubes and of the nature of the container on nitrogen losses are discussed.

Description: 1. The occurrence of stripe smut of rye, Urocystis occulta (Wallr.) Rab. in Great Britain is recorded.2. Control of seed-borne infection by disinfecting seed prior to sowing with an approved organomercury seed disinfectant has been shown.3. Experiments have confirmed that the disease may be soil-borne.4. With the increase of the acreage of rye grown in Great Britain it is suggested that seed should be treated with an approved organo-mercury seed disinfectant as a preventive measure.

Description: 1. Data are presented for the chemical and botanical compositions of ryegrass seed and various by-products of the ryegrass seed cleaning industry.2. Digestibility data are presented for a more limited range of samples of ryegrass seed, ryegrass seed cleanings and, for comparative purposes, of certain by-products of the milling of oats.3. Ground high quality perennial ryegrass seed has a chemical composition and digestibility comparable with that of oats.4. Ground rough (i.e. uncleaned) perennial ryegrass seed has a chemical composition and digestibility such that its starch equivalent is 90–95 % of that of oats.5. Ground bulked ryegrass seed cleanings has a starch equivalent of about four-fifths that of oats and is comparable in feeding value with better grades of oat feed, i.e. those containing not more than about 20 % of fibre.

Description: 1. The daily retention of calcium, carbonate, phosphorus and chloride was studied using four birds and changing the calcium carbonate content of the ration every 5 days for 15 days.2. It was shown that high calcium diets result in a much lower retention of calcium and thin-shelled eggs are produced.3. Retention of calcium was higher in the laying than in the non-laying bird when calcium carbonate was fed.4. High calcium diets depressed the retention of phosphorus, and in one case the retention was negative, even when no eggs were laid. Laying birds gave negative values for retention because of the heavy phosphorus excretion associated with egg laying.5. High calcium diets also depressed the retention of chloride, and on occasion led to negative retention values.

Description: 1. An experiment was performed to obtain information on the fluctuations in excretion of calcium, carbonate, phosphorus and chloride within the day.2. It was found that there was a lower excretion of calcium and carbonate in the 12 midnight–8 a.m. subperiod than in the 8 a.m.–4 p.m. and 4 p.m.–12 midnight subperiods. Phosphorus showed a much smaller variation, whilst chloride gave inconsistent results.3. When eggs were laid there was a distinct increase in phosphorus and chloride excretion and a fall in calcium and carbonate excretion. These changes, although related in time to each other, were not clearly related to the time of oviposition. Thin-shelled eggs did not give the same results, much smaller changes being observed.4. When changes were made in the amount of calcium carbonate added to the basal ration the effect on the composition of the excreta was noted within 4 hr., the full effect showing itself within 16 hr.5. The significance of these results in relation to egg-shell formation is discussed.

Description: A continuous cattle census scheme was started in the Central Province of Nyasaland in 1943, and data thus accumulated on the calving rate of native cattle form the basis of this paper.The system of animal management prevailing in the area is described, and meteorological data collected at Lilongwe over 3 years are also given.

Description: 1. A fraction of soil manganese soluble in buffered pyrophosphate solutions has been identified as three-valent manganese, present in the extract as a soluble complex salt of mangani-pyrophosphoric acid H[MnP3O7].2. Evidence is given to show that a very significant part of soil manganese may be present as three-valent manganese, and that the product of oxidation of divalent manganese in soils is three-valent manganese. In any soil where the production of divalent manganese by reducing processes is going on at any appreciable rate, the oxidation of divalent manganese will supply three-valent manganese, which may therefore be expected to form a relatively large part of the manganese of certain soils.

Description: From time to time during the course of the present war, pig feeders have reported that they have experienced considerable difficulty when making use of extracted palm-kernel meal as a major constituent of the rations of bacon pigs. This has been attributed partly to the lack of palatability of the extracted meal, which leads to a reduction in food consumption and a consequent depression in the rate of live weight increase, and partly to its high fibre content, which causes the ration to be somewhat bulky and of lowered digestibility and nutritive value. The present experiments were designed to throw light on these somewhat contentious matters, since little guidance is to be obtained from the scanty references to this subject in the scientific literature dealing with animal nutrition.

Description: 1. The fertility records of two groups of bulls, one group used for controlled service, and one group used for free service, were compared over a period of one year.2. The fertility of the free-service group was consistently better except during the months of December, January, February and March.3. The difference in fertility between the two groups was correlated with the varying length of the oestral periods of the cows at different seasons of the year.4. It is suggested that the higher fertility in the free-service group was due to a closer relationship of service to the end of heat and thus to ovulation.

Description: 1. 238 samples of carrots comprising over seventy varieties were analysed for total carotenoids (t.c.) during five autumns.2. The average t.c. value for common types (excluding certain very high value varieties and the almost colourless varieties) is 13·8 mg./100 g. fresh carrot. Assuming 90% of the carotenoids to be ‘carotene’ the average for the latter is 12·4 mg./100 g. Negligible correlation is found between named variety and t.c. Red-cored and small-cored varieties are slightly richer than others. The pedigree of the seed is the most reliable indicator of probable t.c. content.3. Six high t.c. varieties and a Red-Cored Chantenay are described in detail. Four of them are of the long slim type with small red cores. One of them (Dippe's Surrey Long) has a mean t.c. value of 37·1 mg./100 g. The high values have been further improved by selection in two subsequent generations.The authors thank Drs L. J. Harris and T. Moore for their interest in this work, and Miss D. Bailey, Messrs A. G. Dockrill and K. R. Symonds for technical assistance.

Description: 1. The seeding rate of radish seed may be influenced by the mechanical effect of the material with which it is treated.2. The seedling emergence of radishes may be improved by treating the seed with an organomercury seed disinfectant.3. The beneficial effect is correlated with adverse weather conditions at the time of germination, and advantages are therefore usually confined to early sowings.

Description: 1. Lactation was studied quantitatively in a heterogeneous stock of laboratory mice, in order to find out whether the milk production of mice could be satisfactorily evaluated from measurements of the growth of the young; and, if individual differences were proved to be readily detectable, to find out to what extent these differences were heritable.2. The total weight of the litter suckled, at 12 days of age, was found to provide a convenient measure of milk production.3. Since the amount of milk given by a mouse is greatly influenced by the number of young suckled, allowance for differences of litter size was made by means of an index of performance which expressed the amount of milk given by a mouse at a particular lactation as a percentage of the average amount given to litters of that size. The index of performance thus evaluated the response of the mouse to a standard stimulus and gave no indication of the maximum productivity of the mouse.

Description: The nutrition of the carrot in a light gravel soil of known analysis with high available phosphate has been studied by statistical pot-culture methods, and the responses, linear and curvature components, etc., due to nitrogen, phosphate, and potash, have been calculated.No hard and fast rule can be made as to the adequacy or otherwise of any particular fertilizer in a soil, as the different parts of the plant (top and root) were shown to be capable of responding quite differently to that fertilizer.

Description: 1. A survey was made of swede fields in Cumberland and it was found that more than half the gross acreage was affected with Brown Heart to a greater or lesser extent.2. The water-soluble boron content of soils from affected and non-affected fields was determined. In general the boron content of fields showing Brown Heart was less than 0·30 parts per million.3. There is a close association between soil texture and the incidence of boron deficiency, a greater proportion of cases occurring on light soils.4. Recent liming rather than the actual pH. level of the soil appears to be correlated with the occurrence of Brown Heart in the field.5. It would appear that some prediction of the possibility of Brown Heart occurring might be made from a knowledge of the ‘available boron’ content of the soil taken in conjunction with such factors as the soil-texture and liming history of the field concerned.

Description: 1. Meiosis was studied in pollen mother cells of the following F1 hybrids: Victory × Avoine d’hiver, Victory × Grey Winter, Argentine × Avoine d’hiver, Victory × Argentine and Avoine d’hiver × Grey Winter.

Description: The fodder cellulose used in this investigation was prepared from wheat straw by the factory process described in the preceding communication. It was dried and milled, so that the resultant material was light and fluffy in character, with the fibres well frayed. This was considered to be important, since the physical state of the cellulose might exert a considerable influence on the ability of the intestinal bacteria to bring about its fermentation and breakdown.It was shown in the preceding paper that the fodder cellulose, on the basis of dry matter, contains 79·8% of crude fibre, of 85·1% digestibility, and 69·2% of ‘total digestible nutrients’. The present feeding trial has demonstrated that the figure for ‘total digestible nutrients’ obtained from the results of the pig digestion trial is a true measure of the productive value of the fodder cellulose for growth and fattening in bacon pigs, provided that the product is fed in a finely divided condition and in intimate admixture with the meal forming the rest of the ration.

Description: 1. The recommencement of the sexual rhythm from deep anoestrus, is described in barren pony mares. Follicular development and oestrus follow after an interval of preliminary changes in the ovaries and accessory reproductive organs.2. The onset of oestrus can be accelerated by general irradiation with strong artificial light. Local irradiation with a mercury vapour lamp has no effect on the ovaries.3. Pregnant matings will result from such artificially induced heat periods provided that ovulation is induced.4. Doses of less than 10 c.c. of sperm injected will cause fertilization when ovulation is so induced.5. There is a close connexion between the shedding of the coat and renewed ovarian activity.6. The stimulus to the ovaries probably passes through the eyes as in the ferret.

Description: 1. The aneurin content of samples of whole oat grain representing six commonly used varieties grown in different districts in Scotland and Wales did not vary widely and there were no appreciable varietal or geographical differences.2. There was a significant positive correlation between aneurin and protein content (r = 0·42).3. During the growth of the oat plant from the flowering stage a steady storage of aneurin in the kernels was observed until the crop was harvested, and there was a simultaneous decrease in the aneurin content of the dry matter of the hulls, leaves and straw, suggesting a translocation of aneurin from the leaves to the kernels during the maturation of the plant.

Description: 1. A large-scale experiment with 274 dairy cows has been carried out to determine whether urea can be a substitute for part of the protein requirement of the lactating. dairy cow.2. It has been emphasized that any proteinsparing effect of urea or other sources of non-protein nitrogen can only be determined in the proteindeficient animal and one of the experimental treatments was therefore designed to supply well below that minimum requirement of protein compatible with milk production.3. The addition of protein to such a ration increasing the percentage of crude protein in the production rations from 12·9 to 17·9 and the protein equivalent from 9·5 to 14·5 resulted in a significant increase in milk production. This gave ample confirmation of the protein deficiency of the low protein ration.

Description: 1. A method of moderate accuracy suitable for the routine determination of potash on a large scale is described.2. Certain minor alterations in the method of precipitation by Lewis & Marmoy are suggested.3. Di-sodium monohydrogen phosphate is suggested as a solvent for the cobaltinitrite precipitate before the permanganate titration, thereby simplifying previous volumetric procedures.The writer wishes to express his indebtedness to the Director of Malacca Rubber Plantations for permission to publish this work. Acknowledgement is also made of the routine work so loyally carried out by his Asiatic staff in the development of the method, especially Messrs Warrior and Thamboo, who were chiefly responsible.

Description: SUMMARYTen fully grown Border Leicester-Cheviot ewes were divided into two groups of five; the heavier ones being about 150 lb. live weight, and the lighter ones about 70 lb. The former were placed on a low plane of nutrition, and the latter on a high plane. As the weights changed by successive amounts of 20 lb. animals were killed and dissected, and their organs and tissues weighed.

Description: SUMMARY1. Pot and field experiments were made to compare the effects of thiosulphates and sulphur on the incidence of manganese deficiency in oat, beet and pea grown in two manganese-deficient soils.2. The addition of sodium or calcium thiosulphate to oat plants growing in a manganese-deficient fen soil in boxes markedly reduced symptoms of ‘grey speck’ and increased the soluble manganese content in the leaf tissues, but the effect was transient.3. The growth of beet in this soil in clay pots was improved by the addition of thiosulphates, and also by painting the exterior of the pots with bitumen paint or by covering the surface of the soil with a thin layer of sand. The thiosulphate treatments increased the manganese uptake by the plants and reduced the symptoms of manganese deficiency, particularly when applied to pots painted with bitumen paint.4. Field experiments with an old garden soil deficient in manganese showed that thiosulphate treatments increased the manganese uptake of beet. Placement treatments were more effective than broadcast treatments and greatly improved the growth of beet and reduced or eliminated manganese-deficiency symptoms, without producing any change in soil pH.

Description: SUMMARY1. A study of different methods of staple-length measurement of material from a cotton variety trial, of the comparative accuracy of three persons' measurements and of the number of seeds which it is necessary to measure in order to achieve various degrees of accuracy in the determination of differences in variety trial and single plant material is described.2. If, in making single plant selections, the breeder is satisfied with a level of significance of P =0·1 when using a sample of only five seeds per plant, he would be justified in discarding material falling one and a half millimetres below the standard of staple-length at which he was aiming.

Description: SUMMARY1. Metabolism experiments have been made with five sheep fed iodinated casein in doses sufficient to give symptoms of hyperthyroidism, ranging from moderate to severe. Two comparable sheep were included to serve as controls.2. The same ration was used throughout each experiment, and it was found that the digestibility of its dry matter and of its crude protein content declined when the sheep were made hyperthyroid. This was due to increased peristalsis.3. The treated sheep lost body N when iodinated casein was given, the loss being proportional to dosage. Calculations indicated increases in the endogenous catabolism by up to 120%, and also increases in deamination.4. There was an increased excretion of urea and ammonia during hyperthyroidism, the latter being associated with a decrease in the plasma carbon dioxide combining capacity.5. Purine catabolism was accelerated by more than 50% in some sheep. Starvation of one sheep did not depress nucleoprotein catabolism as it does in the normal sheep.

Description: SUMMARYMoisture content and temperature are of first importance in the storage of seeds. Seeds are usually stored in porous containers like sacks and paper bags, and their water content fluctuates with the humidity of the surrounding atmosphere. In sealed chambers, on the other hand, the humidity of the atmosphere will be determined by the water content of the seeds and, with different kinds of seeds in an enclosed space, an exchange of water will occur until equilibrium has been reached. This does not mean, however, that different kinds of seeds, or even different samples of the same kind will have exactly the same final water content, since the water content/humidity relations are affected by differences in structure, chemical composition and previous drying treatment; it is permissible, however, for practical purposes, to ignore the slight differences which occur between samples of the same kind of seed.

Description: SUMMARYThe available data on calcium, phosphorus and carbonate balance experiments with laying and non-laying birds have been collected and condensed. From this condensed data the following relationships have been derived:(1) Calcium excretion is a function of calcium intake.(2) Phosphorus excretion is a function of phosphorus intake.(3) Carbonate excretion is a function of carbonate intake.(4) Carbonate/calcium ratio of the excreta is a function of carbonate/calcium ratio of the intake.(5) Calcium/phosphorus ratio of the excreta is a function of calcium/phosphorus ratio of the intake.

Description: SUMMARYThe effects of cobalt deficiency and of varying degrees of copper deficiency in young sheep were investigated.Five of six evenly matched groups of hoggets aged about 8 months when transferred to the deficient pastures were supplemented with the equivalent of 1 mg. Co/day, 10 mg. Cu/day, 1 mg Co + 1 mg. Cu/day, 1 mg. Co + 5 mg. Cu/day, 1 mg. Co + 10 mg. Cu/day, respectively, administered thrice weekly as a drench; the sixth group was untreated.All individuals that received no cobalt developed typical symptoms of cobalt deficiency and most of them died within a year. After 11 months the remaining cases were removed to the laboratory. They were then in the advanced stages of the terminal cachexia.

Description: 1. The object of this investigation has been to advance knowledge of the methods necessary for the practical application of the transplantation of fertilized ova in cattle.2. The induction of ovulation at any specific time can be produced by squeezing out the corpus luteum per rectum. Oestrus occurs from 2 to 4 days afterwards; this is accompanied by ovulation and the ova so produced are readily fertilized. The onset of oestrus after the expression of the corpus luteum is hastened by previous treatment with P.M.S.3. The induction of multiple ovulations is necessary to produce an augmented supply of fertilized ova, but it is of primary importance that the ova so produced are fertilized, viable and capable of full development. Four methods of doing this have been tested.

Description: Two examples are given of field trials for which randomized blocks would seem the most suitable design, but in which special considerations of the future of the trial or the nature of the treatments make complete randomization impossible or impracticable. A type of design which takes account of these difficulties is described, together with the appropriate methods of analysis.The author wishes to thank Mr S. C. Pearce for much valuable advice throughout this investigation.

Description: SUMMARYThe metabolism trials described in the present communication were undertaken with the object of testing the conclusions arrived at in farm-scale feeding trials, designed in accordance with the requirements of the modern statistical lay-out, respecting the minimum protein supply needed to support the maximum rate of growth in bacon pigs.

Description: Some disorders causing chlorosis and necrosis of the foliage of oil palms from three West African estates have been investigated by spectrochemical analysis of the dry leaflets for potassium, calcium, magnesium and manganese.Statistical examination of the chemical analyses of leaflets from fronds of different ages, and from different positions along the frond, shows that it is important to sample and analyse separately at least upper, middle and lower fronds from each tree. Little is gained by analysing separately samples from different positions along the length of the frond.The ‘bronzing’ diseases are tentatively ascribed to deficiency of potassium. One palm is probably a case of combined magnesium and potassium deficiency. One disease, ‘lemon frond’, cannot be attributed to a deficiency of any of the elements determined.The differences in mineral composition of the leaflets between palms from the three estates are greater than those due to the diseases and a further survey is proposed to determine the range of variation of composition of healthy trees and the levels below which deficiencies set in.

Description: 1. Chemical analyses have been carried out on the muscular and fatty tissues from thirty-one beef animals and twenty-nine lambs, and also on the psoas muscle from twenty-nine pigs. The animals were selected to represent a very wide cross-section of our meat industry.2. The water content of muscular tissue (psoas muscle), calculated on a fat-free basis, was found to be the same for cattle, lambs, and pigs (immediately after death), the average being about 78%.3. Similarly, the original water-content of the fatty tissue (perinephric), calculated on a fat-free basis, was found to be the same for cattle and lambs, being on the average about 81–82%.4. The average water-content of boneless meat (i.e. the combined muscular and fatty tissues from a whole side or carcass) was the same for cattle and lambs, being about 79% (on a fat-free basis), shortly after death.5. In all these cases there was no significant difference between the different species.

Description: In this study samples of the mixed milk from a herd of sheep were taken weekly for analysis throughout a season of approximately 7 months. The following are the mean values obtained: sp.gr. 1·0350, S.e.m. 0·0002; acidity 0·226%, S.e.m. 0·003; fat 8·00%, S.e.m. 0·07; S.n.f. 11·35%, S.e.m. 0·06; and total N 0·920%, S.e.m. 0·007.Samples were also taken at 2-week intervals throughout the lactation period of six individual ewes of the Rahmany breed and of the same number of the Awsemy breed. The variation in the composition of their milk throughout lactation and also the variation due to individuality are discussed.

Description: A study has been made of the distribution of the various fractions of phosphorus in the Blairmont clay soils. Nearly three-fifths of the total phosphorus is present in the organic and inorganic alkali-soluble forms.The organic alkali-soluble phosphorus and the exchangeable phosphorus vary in direct relation to cane production and to phosphorus content of the juice. The Truog phosphorus values are nil for all three soils and do not give a satisfactory indication of the phosphorus-supplying ability of the soils.The soils have a high anion exchange capacity (23· mmol. of phosphorus per 100 g. of soil). It is indicated that the high fixing power of these soils for phosphorus is largely a mechanism of anion exchange reactions.

Description: 1. It has been shown in a previous paper (Callow, 1948) that, with ‘standard’ carcasses of cattle, sheep and pigs containing more than 18 % of fatty tissue, FT/C, there is a close correlation between FT/C and MT/C, the percentage of muscular tissue. This is shown by the linear regression equationMT/C = 76·1 — 0·684FT/C ± 1·0 (r= — 0·9782).The reasons for this close correlation and the effects of varying rates of fattening on the constants of the generalized equationMT/C = a — bFT/Chave been deduced by a mathematical and biological analysis of the data.

Description: 1. A field experiment in which ninety-seven farms co-operated has been carried out to find whether giving cows a daily dose of 20 g. of iodinated casein, incorporated with an additional allowance of concentrated food, could be used to increase milk yields for short periods on commercial farms. The results have been analysed statistically, and the causes of variation in the response to iodinated casein have been investigated. The farms supplied 1164 cows, and 1008 cows were finally included in the analysis. Not all of the seventy-eight pairs which were deleted were discarded, and some could legitimately be used in certain parts of the analysis.2. 4% of the cows refused the iodinated casein cube. The refusal rate was higher in the Channel Island cattle which are known to be fastidious feeders

Description: 1. The influence of different levels of dietary calcium upon egg-shell thickness and uniformity of egg-shell thickness is discussed.2. The low calcium diet caused a gradual thinning of the shell, but no soft-shelled eggs were laid.

Description: 1. With the object of determining the vitamin A value of carotene in different green fodders, an investigation has been undertaken to study (i) the relation between the chemically determined carotene and its biological activity as compared with that of standard carotene, (ii) the purity of apparent carotene from different sources, (iii) absorption of carotene in rats, and (iv) the relative efficiency of the standard carotene and preformed vitamin A.2. Biological tests have shown that the chemical method of assay is a fair index of the true carotene content in green fodders, and carotene in the form of an extract is quite as effective in the system as that present in the plant tissues. β-Carotene appears to be predominant in these materials.

Description: Experiments are described in which the ‘once-used’ soils left over from previous culture experiments were employed as aggregates in the growth of vegetables. It was demonstrated that sand with full nutrients was superior to ‘once-used’ soil with water only, but that ‘once-used’ soil supplied with the full quota of soluble nitrogen was superior to the sand with full nutrients. The root of the cabbage in sand was an exception, and a possible explanation was that sand as aggregate favoured true root formation, while soil favoured the formation of tops. The ‘once-used’ soil in these experiments deteriorated in physical propertes owing to the conditions of the experiment, which included the use of nitrogen as sodium nitrate, possibly owing to the tendency to the formation of sodium clay; it is argued that a judicious choice of fertilizers and/or the use of flocculating electrolytes should overcome such tendencies.

Description: A convenient method of introducing into a field experiment additional factors which can be applied to smaller areas than that of the whole plots is to use split plots: each whole plot is split into sections, and the different combinations of the additional factors are randomized over each set of sub-plots. An extension of this idea is the device of split-plot confounding, by which not all the combinations of the additional factors are used in every whole plot; instead, the possible combinations are subdivided into two or more sets which are then assigned to blocks and whole-plot treatments in a balanced manner, in such a way as to confound certain interactions of the additional factors between whole plots and certain higher order interactions between blocks.

Description: Repeated attempts have been made, both during the recent war and the war of 1914–18, to make the store of starch and other nutrients in the horse-chestnut available for farm animals. Unfortunately, the extremely bitter taste of the horse-chestnut, due to the presence of saponins and, to a smaller extent, of tannins, has proved a severe obstacle, and horse-chestnuts have been found to be an unsuitable food for livestock both on account of their unpalatable character and their constipating action.

Description: 1. Crops sensitive to manganese deficiency are generally healthy on soils with more than 0·3 mg. exchangeable Mn%, but they may also be healthy on soils with less than this amount.2. Other fractions of the soil manganese, including those which are either readily reducible or soluble in sodium hexametaphosphate, are no more successful than the exchangeable manganese in characterizing deficient soils.

Description: The dry-matter content of about 260 samples of potatoes was determined. The samples were collected over three seasons and from many types of soil.The average dry-matter content of a variety varied from season to season, but it always bore an approximately constant relationship to the average value of other varieties.Wet seasons led to potatoes low in dry matter.The variation in the content of dry matter of potatoes in different seasons and from different soil types is not a direct effect of the water balance of the tubers.The average content of dry matter of potatoes depends on the soil in which they were grown; fen and blackland gave potatoes with the lowest dry matter, followed by skirt, silt and warp, then loam and medium loam, then clay, and the highest dry matter occurred in stocks grown in sands, gravels or light loams.The difference between the soils is discussed, and it is tentatively concluded that the factor responsible for the variation in content of dry matter of the potatoes is the available water content of the soils.

Description: A suitable method of fluorimetric determination of riboflavin was developed, and riboflavin in various poultry feeding stuffs was determined by its use.Riboflavin was determined in fodder plants, vegetable refuse and wild plants. The influence of seasonal changes and of different stages of growth on the riboflavin content in fodder plants was investigated. Summer-grown plants contain more riboflavin than those grown in the rainy winter season. The riboflavin content of the plants declines in the course of their growth.

Description: The effect of beet yellows virus on the yield of sugar beet was tested in the presence and absence of various fertilizers and farmyard manure. In general the manorial treatments increased the root and sugar yields of both infected and healthy plants, but the losses caused by infection increased proportionally as the mean yields increased. When the effects of nitrogen, farmyard manure and salt on mean yield were large, the losses caused by infection were increased more than proportionally.The fertilizers had little effect in varying the symptoms of the disease. There was some indication that the red colour associated with some varieties of sugar beet was intensified by deficiency of phosphate and potash.The effect of fertilizers on rate of spread of infection was variable, and again appeared to depend largely upon the magnitude of the fertilizer effects on mean yield. Nitrogen, phosphate and potash occasionally had positive effects, and salt had a fairly consistent negative effect. None of the effects appeared to be of any economic importance.

Description: 1. In pony mares during oestrus in which a follicle was considered to be sufficiently ripe (thin walled) the intravenous injection of 500 i.u. pregnancy urine extract induced ovulation in nineteen out of twenty-three mares between 24 and 48 hr., in three cases within 24 hr., and in one case between the fourth and fifth days.2. Dialysed egg yolk as a medium for storage of horse sperm for 24 hr. was shown to give satisfactory results when ovulation is controlled by the above method, so that it occurs within 24 hr. after insemination. Nine single inseminations during one oestrus resulted in five pregnancies.3. The number of spermatozoa required for successful inseminations is discussed.4. Means of detecting a sufficiently ripe follicle before injection with pregnancy urine extract are described.5. It is shown that the duration of oestrus is shortened as the result of pregnancy urine injections.6. Data is given concerning the time which elapses between ovulation and the cessation of oestrus.

Description: Caecal coccidiosis of rather more than usual severity has been found to develop in chicks folded on a stemmy type perennial rye grass pasture at Hanns Hall Farm this season.Subsequent brooder house experiments have demonstrated that chicks receiving a diet relatively low in protein and fibre content and relatively high in starch content, as cereals, failed to develop coccidiosis when subjected to severe infestation by coccidial oocysts, while the chicks in the same brooder house on a diet containing more roughage developed acute coccidiosis, and other chicks in the same brooder house on a diet containing a relatively high proportion of protein developed chronic coccidiosis.As these experiments have shown that coccidiosis occurs on diets designed to promote proliferation of anaerobic bacteria in the intestines, and, conversely, does not occur when chicks are fed a diet designed to depress the proliferation of undesirable bacteria in the intestines, it would appear that coccidiosis in chicks is a secondary complaint, the primary aetiological agents being bacteria which proliferate to excess in the presence of roughage or protein.Attention is drawn to the occurrence of postcoccidial abscesses which may occur after apparent successful treatment with Sulphamezathine for the cure of coccidiosis.

Description: The present communication deals with the results of an inquiry into the possibility of utilizing dried penicillin felt, a by-product of the manufacture of penicillin, in the feeding of livestock. The availability of this by-product on a suitable scale afforded an opportunity of obtaining information about the digestibility and biological value of a mould protein. During the course of the investigation, digestion trials with both sheep and pigs, and a farm-scale feeding trial with bacon pigs, have been carried out.

Description: Kale silage was made in five large silos and the losses of dry matter and kale constituents determined.The losses of dry matter averaged 33%, of N-free extract 41% and of crude protein 34%.The percentage losses are higher than with wellmade grass silage, but, nevertheless, the yields of silage (and animal nutrients) per acre compare very favourably with those of other crops, including grass.Inclusion of straw in kale silage did not reduce losses of dry matter; it merely reduced slightly the quantity of water lost.