bluuebunny/crossref_metadata_2025 huggingface dataset:
Some Observations on the Assimilation of Atmospheric Nitrogen by a Free Living Soil Organism.—Azotobacter Chroococcum of Beijerinck
Authors: Ashby S. F.
Published: March 2009

Some years before the appearance of Hellriegel and Wilfarth's work on the sources of nitrogen of leguminous plants, and while the part played by atmospheric nitrogen in the nutrition of crops was under active discussion, Berthelot was making some exact observations on the behaviour of uncropped soils towards the free element. He found that when 50 kilograms of air-dry arable soil were exposed to the air and rain in a vessel for seven months a great increase in the nitrogen content could be observed; the total nitrogen of the original soil had increased from 50 grams to 63, or a gain of over 25 per cent, after allowing for the small amount of combined nitrogen brought down by rain; in another experiment where the soil had first been washed free from nitrates, a gain of 46 per cent, of nitrogen was proved. In many other cases, however, the gain was only from 10–15 per cent, of the original nitrogen present in the soil.
The Effect of Partial Sterilisation of Soil on the Production of Plant Food
Authors: Russell Edward John , Hutchinson Henry Brougham
Published: March 2009

When soil is partially sterilised, either by heat or by volatile antiseptics like carbou disulphide, toluene, etc., it becomes more productive and capable of yielding larger crops. The effect of heat was discovered incidentally about 25 years ago by the early soil bacteriologists; the action of carbon disulphide was first noticed somewhat later by a vine grower who had used it to kill phylloxera. Both cases have since been studied by several investigators, notably Koch and Hiltner and Störiner; a paper was also recently published by one of us in which it was shown that the property is a general one, holding for all the soils and volatile antiseptics examined and for all the plants, excepting those of the leguminous order. Thus when a soil had been heated to 95° C. it produced two, three, or sometimes four times as much crop as a portion of the soil which had not been heated, whilst treatment with volatile antiseptics led to an increase in crop varying between 20 and 50 per cent.
The Flow of Water and Air through Soils
Authors: Leather J. Walter
Published: March 2009

In Part I of the current volume of this Journal Green and Ampt make certain assumptions regarding the factors which control the rate of flow of water and air through soils, the basis of which is that the channels in a soil may be regarded as a bundle of capillary tubes, and that the velocity of flow of a liquid will consequently conform to Poiseuille’s formula. Such an assumption cannot however be maintained. Poiseuille’s formula was deduced from the ascertained rate of flow of liquids through straight tubes of approximately uniform diameter; the latter being 1 mm. or so. The formula is not however really accurate even under these limited conditions, as was shown by Thorpe and Roger, who found it necessary to add the correction – ρV/8πlt. But the passages through the soil are not straight or of uniform diameter for any measurable distance, in fact they are wholly irregular, which Green and Ampt recognise, for they describe them as “irregular in area, length, direction and shape.” But this being the case, Poiseuille’s formula obviously cannot be expected to apply.
The Fungicidal Action of Bordeaux Mixtures.
Authors: Barker B. T. P. , Gimingham C. T.
Published: March 2009

The mixture of copper sulphate and lime universally known as Bordeaux mixture has been in common use as a fungicide in many countries for some time; but it is still uncertain by what means such a mixture, containing no soluble copper, is effective. It has undoubtedly a physiological effect upon plants on to which it is sprayed, and may increase their powers of resistance to the attack of parasites; but in addition to this, there appears to be a direct fungicidal action which requires explanation.
The Action of Rennet on Milk
Authors: Nierenstein M. , Stubbs Jessie
Published: March 2009

During the renneting process in the manufacture of Cheddar cheese a retardation of the time of coagulation has often been noticed though the acidity had reached the required strength before the rennet was added to the milk. The cause or causes of this retardation are of great technical importance as they lead to infection of the milk with consequent production of taints. As the two main factors of coagulation are (i) the acidity of the milk when renneted, and (ii) the calcium salts of the milk, we approached the inquiry from these two points and tried to answer the following questions:—
On Ovariotomy in Sows with Observations on the Mammary Glands and the Internal Genital Organs
Authors: Mackenzie K. J. J. , Marshall F. H. A.
Published: March 2009

(1) Distinct changes take place in the tissues of the mammary region in sows during the period of heat. These changes consist mainly of congestion of the glands. Moreover the part affected is in the pig of much commercial value.

(2) The black pigment often found in the mammary tissue of black sows is not associated with the recurrence of heat, and the bacon manufacturer who wishes to differentiate between sows slaughtered at this period and other sows must not rely on this pigment as a guide.

(3) Since ovulation occurs during oestrus and not during prooestrum it is advisable to “hog” the sow towards the end of her heat period.
Further Studies of the Effects of Smoke from Towns upon Vegetation in the Surrounding Areas
Authors: Crowther Charles , Steuart Dan. W.
Published: March 2009

In two previous communications a summary has been given of the results obtained in determinations of the relative degree of atmospheric pollution, firstly in various parts of the city of Leeds, and secondly in the surrounding semi-urban and rural areas, to a distance in some directions of seven miles from the centre of the city. The results obtained in the latter series indicated clearly the presence of extensive atmospheric pollution, showing the characteristics of coal smoke, in all parts of the area investigated. The degree of pollution was found to fall rapidly on passing in a northerly direction from the centre of the city into an area free from smoke-producing industries, but less rapidly on passing into similar areas to the north-east and east of the city, owing to the greater dispersion of the city smoke in these directions by the prevailing winds. On the opposite side of the city, from north-west round by south to south-east, smoke pollution was found to be very high in all quarters.
The determination of potash in soils
Authors: Dodd A. H.
Published: March 2009

In June, 1921, the writer undertook a series of soil analyses in connection with the field trials organised by Dr J. A. Hanley for the Department of Agriculture at the University of Leeds. The soils were of diverse kinds and included samples of most formations from the Carboniferous upwards, most of which were from poor unmanured grass land. They were of obviously low potash content.
Sunflower silage
Authors: Amos Arthur , Woodman Herbert Ernest
Published: March 2009

One of the main problems confronting the advocates of silage in this country is the selection of crops suitable for being grown for ensilage purposes, particularly in view of the fact that attempts to produce maize silage in this country have frequently been unsuccessful. It has been demonstrated, in trials extending over a number of years at Cambridge, that the mixed oat and tare crop can be used for the production of silage with success. The silage from oats and tares, when made under favourable circumstances, is possessed of great palatability and excellent nutritive value, and moreover, the process, considered from the point of view of losses of ingredients as a result of silo fermentation, is, if anything, more economical than that by which maize forage is converted into silage (1).
The soil-point method for directly estimating the water-supplying power of a soil in the field
Authors: Hardy F.
Published: March 2009

1. Attention is drawn to Mason's modification of Livingston's soilpoint method of directly estimating the water-supplying power of a soil in situ. Mason used ordinary lead writing pencils as soil-points.

2. This method, heretofore tested only in the laboratory, has been employed by the writer in an ecological field study. Details of the procedure adopted are described, and the reliability of the method is indicated by the presentation of a series of mean results with their corresponding probable errors.

3. It is concluded that the method is practicable; it should prove of considerable usefulness to workers in ecology.
The influence of the administration of certain oils on the nutritive value of the butter fat of cows on winter rations
Authors: Drummond Jack Cecil , Channon Harold John , Coward Katharine Hope , Golding John , Mackintosh James , Zilva Sylvester Solomon
Published: March 2009

(1) Further experiments are described, the results of which support the relationship between the presence of vitamin A in the diet of the cow and its presence in milk fat.

(2) The typical winter ration of concentrates, roots and hay may be adequate to maintain the vitamin A value of the milk fat for considerable periods provided that at least one of the components supplies adequate amounts of that dietary principle. Well cured green meadow hays are in this respect greatly superior to dry brown seeds hays.

(3) The addition of cod liver oil to a winter ration deficient in vitamin A will induce a sharp rise in the vitamin A value of the milk fat of cows. No such effect is seen when oils deficient in this dietary factor (coconut oil, arachis oil) are given.

(4) The administration of cod liver oil in doses from 1 to 8 ozs. daily to milking cows caused no “fishy” taint in the milk or butter-fat.

(5) The administration of cod liver oil caused no appreciable change in the yield of milk but the higher doses appeared to cause a noticeable drop in the percentage of fat. Further experiments are required to throw more light on this observation.
The form of mechanical composition curves of soils, clays, and other granular substances
Authors: Robinson G. W.
Published: March 2009

1. The mechanical analysis of a number of soils, clays, and other granular materials has been carried out by the writer's method and the results have been set out in the form of curves showing the relationship between summation percentages and logarithm of settling velocity.

2. The curves obtained are smooth. This suggests that all the necessary information as to the mechanical composition of a material can be obtained by using a relatively small number of experimental points and drawing the appropriate curve. Results obtained on one scale can readily be transferred to another scale by interpolation.

3. The most common type of curve is a sigmoid. The steepest portion of the curve represents the fraction present in greatest frequency. This has been termed by the writer the modal fraction. Two sub-types were found. In the case of certain heavy clays, the modal fraction appears to be at the lower end of the curve, whilst in the case of materials mechanically disintegrated the modal fraction is at the upper limit of particle size.

4. Composite curves are obtained in certain cases. They may represent mixtures of different materials, or soils in the earlier stages of formation from rock.

5. The lower limit of particle size appears to be represented by log in the case of normal soils and clays. In the case of certain finely divided but non-plastic materials, the lower limit appears to be in the region of . It is suggested that a better picture of the properties of soils would be obtained by taking the limit for clay at this poiDt instead of at log .

6. The use of the logarithm of settling velocity as a measure of particle size is discussed and it is suggested that the use of negative logarithms might be avoided by using log (v × 107), for which the symbol Lv is proposed.
The digestibility of oat and tare silage
Authors: Wood Thomas Barlow , Woodman Herbert Ernest
Published: March 2009

During the last decade the production of silage has, in various parts of the country, become a matter of considerable importance, and many scientific investigations in connection with this practice have been carried out. The bulk of this work has been directed towards the study of the changes undergone by the crop in the silo, together with the determination of the character and the amount of the losses which occur. Little or no attention has been given to the question of the digestibility of silage, although it is of obvious interest to determine how the digestibilities of its ingredients compare with those of the green crop from which it has been made. The investigation to be described in this communication is preliminary to one of larger scope, which will have for its object the comparison of the digestibilities of the green fodder, hay and silage of the oat and tare crop. A knowledge of these comparative data, when considered in conjunction with the available information regarding the losses sustained by the crop in the making of hay and silage, will enable the question of the relative economy of hay and silage production to be settled.
A quantitative relation between soil and the soil solution brought out by freezing-point determinations
Authors: Keen Bernard A.
Published: March 2009

An examination has been made of some of the extensive experimental data obtained by Bouyoucos and his associates on the freezing-point depression of soil solution at varying moisture contents, examined in situ.

These workers find that the soil solution in quartz sand and extreme types of sandy soil obeys approximately the same law as dilute solutions—the freezing-point depression varying as the concentration, or in the present case, inversely as the moisture content. In other words

where K is a constant, and Dn is the freezing-point depression, at a moisture content of Mn. Soils do not obey this law, the freezing-point depression rapidly increasing as the moisture content decreases.
Studies of growth and development in the young pig Part II. A comparison of the performance to 200 lb. of pigs reared along different growth curves to 56 days of age
Authors: Elsley F. W. H.
Published: March 2009

1. Twenty blocks of four litter-mates were individually fed under standard conditions from 56 days of age to 200 lb. Each block consisted of three early-weaned pigs reared to 50, 40 and 30 lb. live weight, respectively, at 56 days of age and a suckled pig reared to 50 lb. live weight at 56 days of age.

2. There was no difference in the growth rate and feed conversion from 56 days of age to 200 lb. of the early-weaned and suckled pigs reared to 50 lb. at 56 days of age.

The age at 200 lb. of the 30, 40 and 50 lb. early-weaned pigs were 169·8, 176·8 and 182·7 days and the lb. of meal per lb. live-weight gain 3·3, 3·2 and 3·1 lb., respectively. A reduction in 56-day weight led to an increase in growth rate and feed conversion from 50 to 200 lb. live weight.

3. The conformation and composition of the bacon carcasses of the 50 lb. early-weaned pigs were not significantly different from the carcasses of the suckled pigs which also weighed 50 lb. at 56 days of age.

An extensive examination of the carcasses of early-weaned pigs showed that an increase in 56-day weight from 30 to 50 lb. live weight signifieantly reduced the weight of muscle present and significantly increased the amount of subcutaneous fat. The conformation of the carcasses was not affected.
Meiotic irregularities in hexaploid oats: II. A cytological survey of the variety Picton
Authors: Howard H. W.
Published: March 2009

1. Picton, a winter-hardy variety of oats selected from the cross Argentine x Grey Winter, contains plants which have irregular meiotic divisions.

2. Two types of irregularities were observed: first, univalents and the products of their division; and secondly, bridges and fragments at both first and second divisions.

3. Plants selected for a low frequency of irregularities produced offspring with a low frequency of irregular divisions. On the other hand, plants with regular divisions were also obtained from parents which had a high frequency of irregularities.

4. It is pointed out that the genetical effects of bridge chromatid formation and breakage is the production of gametes deficient for chromosome segments. There is some evidence that chlorotic plants are produced when such deficiencies become homozygous.

5. It is suggested that the meiotic irregularities produce a certain degree of heterozygosity which may make Picton more adaptable, and at the same time give it a certain degree of hybrid vigour.
The inception of lactation in the cow and goat
Authors: Asdell S. A.
Published: March 2009

Part I. The changes in amount and composition of the mammary secretions of a heifer in its first pregnancy are recorded.

The most striking feature is the abrupt appearance at half-way through pregnancy of a viscous secretion consisting largely of globulin.

These results are extended to the primiparous and to the multiparous “dry” goat.

Colostrum is shown to be normal milk admixed with the globulin secretion.

The significance of the globulin is discussed. Reasons are advanced indicating that it may be an excretion of the cell when it changes from the growth phase to the secretory phase of life.

The stimulus to mammary growth is briefly discussed.

A partial analysis is given of the secretion from the tubercular udder of a cow. This secretion resembles somewhat the secretions of mid-pregnancy.

Part II. Instances are given of cases of premature lactation in the goat, and analyses are recorded of these secretions.

These cases are discussed in the light of Part I of this paper, and their bearing on the corpus luteum theory of mammary development is considered. The sexual precocity of the goat is such that the mammary growth may in all cases have been due to luteal influences.

A few cases of premature lactation in the cow are also reported.

The theory that the foetus produces a hormone inhibiting lactation is shown to be unnecessary.
Control of ovulation in the cow
Authors: Hammond J. , Bhattacharya P.
Published: March 2009

1. Cows and heifers were injected shortly before slaughter with an extract of horse pituitary or with pregnant mare serum gonadotrophin.

2. These substances were administered at different times of the cycle or in pregnancy; various doses were given simultaneously with removal of the corpus luteum.

3. A series of animals were given 1500 or 5000 i.u. at intervals from 5 days before to 3 days after expression of the corpus luteum; up to thirty ovulations were so obtained.

4. A small number of cows have been treated and left to calve; there have been several twin and triplet births.
Observations On the Characteristics of the Semen in Relation to Fertility in the Bull
Authors: Laing J. A
Published: March 2009

1. The characters of the semen of twenty-one bulls were compared with their fertility as expressed by the service rate—the number of services required for each conception.

2. It was found that, on the basis of the density of the semen, the total number of spermatozoa ejaculated, the motility and change inpH of the semen on incubation at 37° C, the animals could be divided into a higher fertility group with service rates from slightly more than 1·0 to about 3·5, and a lower fertility group with service rates from above 3·5 to ∞. Totally sterile animals could be detected.

3. It is suggested that other factors than the quality of the semen can vary fertility so as to give service rates at different levels from 1·0 to about 3·5. Below a certain level of semen quality fertility appears to be impaired no matter what other factors operate.

4. No relationship could be detected between the percentage of abnormal spermatozoa ejaculated and the service rate.

5. Standards for use in diagnosis of fertility are suggested.
The nutrition of the bacon pig: X. The value of extracted palm-kernel meal in the feeding of the bacon pig
Authors: Woodman H. E. , Evans R. E.
Published: March 2009

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.
Studies in Tropical Soils I. Identification and Approximate Estimation of Sesquioxide Components by Adsorption of Alizarin
Authors: Hardy F.
Published: March 2009

1. An alizarin-adsorption method discovered by Schmelev has been successfully applied, with suitable modification, to the identification and approximate estimation of the free sesquioxide components of clays and soils.

2. Details of the tested procedure are presented, together with some preliminary results obtained.

3. The free alumina component of clays and soils appears to adsorb alizarin only after ignition, whereas the free iron oxide component adsorbs it only in the fresh, unignited state. Hence, by applying the procedure to the fresh, as well as to the ignited material, an approximate estimate of both components may be accomplished in a relatively short time.
The variation in the copper content of the blood of normal sheep
Authors: McDougall E. I.
Published: March 2009

The blood copper of normal sheep from the Institute flock at Cambridge was studied over the period October-April for three lambing seasons and showed no changes characteristic of pregnancy; in contrast to the behaviour of human beings and possibly sheep of low copper status. What changes there were took place in both pregnant and nonpregnant sheep, did not reflect the transfer of copper to the foetus and appeared to be due to extrinsic factors.

Comparison of the blood copper of the lamb with that of its dam for four lambing seasons showed that it was a changing quantity at birth, being lower in the foetus, variable a few hours after birth and higher some days later than in the ewe.

The blood copper of suckling lambs was studied from birth in February-March until June, for three seasons. There tended to be high values in the first 1 or 2 weeks of life, which decreased in the course of approximately 10 weeks.
Chick Rearing III. The effect of diet on vitamin A, xanthophyll and carotene metabolism
Authors: Mann T. Barton
Published: March 2009

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.
The Sticky Point Water of Soils. Part II
Authors: Marchand B. De C.
Published: March 2009

Keen and Coutts(8) and Coutts(1) have suggested that the percentage of water in a soil at the sticky point is related to the colloidal content of the soil, as measured by “loss on ignition,” in the following manner:

S = mI + c,

i.e. by a rectilinear equation, and point out that the figure obtained for c approximates to the theoretical percentage of water held in the interstitial spaces of an ideal soil.
Effect of the level and concentration of liquid milk substitutes fed to early weaned calves
Authors: Burt A. W. A. , Bell E. O.
Published: March 2009

1. The effects of feeding 6 or 9 oz. of milk substitute in 2 or 3 pints of water per feed were studied in Ayrshire calves weaned at 5 weeks, and of feeding 6 or 9 oz. in 3 pints with calves weaned at 3 weeks.

2. In both experiments higher milk substitute intakes significantly improved growth rate without detriment to the consumption of dry food.

3. Restriction of water to 2 pints per feed tended to reduce live-weight gain and concentrate consumption and increased free water intake, although not sufficiently to compensate for the restriction.

4. In calves weaned at 3 weeks the higher amount of milk substitute produced an effect which was still present at 88 days and this indicated that underfeeding in very early life may be permanently detrimental.

5. Regressions of live-weight gain upon concentrate and free water consumption and the progressive increase in live-weight gain and concentrate intake before weaning indicate the importance of this intake in providing energy for the calf before weaning and the beneficial effects of individual vigour.

6. The marked effects of the various systems of use of similar foods upon the distribution of liveweight gain during the first month and upon cost are described and discussed.
The mechanism of cellulose digestion in the ruminant organism
Authors: Woodman H. E.
Published: March 2009

During the carrying out of the series of researches which led to the formulation of the well-known expression for calculating the starch equivalent of a feeding stuff, Kellner(1) was led to investigate the value of crude fibre in the fattening ration of oxen. For this purpose he used material which had resulted from the boiling of rye straw with an alkaline solution under pressure, the object of this treatment being to free the cellulose of the straw from incrusting substances. This fibre-rich preparation was added to a basal ration which was slightly in excess of maintenance requirements. The result produced by the addition to the basal ration of the digestible matter derived from the fibre of the treated straw was found by Kellner to be equal to that produced by the addition of an equal weight of pure starch. The conclusion was therefore warranted that the digestion products of cellulose in the ruminant organism are equal, for purposes of fat formation in the body, to those derived from the digestion of starch. This finding is given practical expression in Kellner1s formula for calculating the starch value of a feeding stuff, an equal value being attached to digestible fibre and digestible carbohydrate.

It is clear that any theory which is put forward to explain the breakdown of cellulose in the ruminant tract must be compatible with the experimentally demonstrated fact that the products of such digestion of a given weight of digestible fibre are equal in nutritive value to the products derived from the digestion of the same weight of starch.
Investigations on yield in the cereals: V. A Study of four wheat fields: the limiting effect of population-density on yield and an analytical comparison of yields
Authors: Doughty L. R. , Engledow F. L.
Published: March 2009

In any field of corn the population-density or number of plants per unit length of row is very fluctuating. Accidental circumstances may result in considerable stretches being empty or thinly populated. Quite apart from this, the population of successive short lengths is sharply and characteristically inconstant. Where plants are few tillering is profuse and there is thus a tendency towards constancy in yield per unit length of row. Specific ascertainment has, in earlier experiments, suggested that the tendency is by no means marked. In consequence fluctuation of population-density in the sense here used, reduces yield in typical field crop substantially below the potential maximum appropriate to the soil and other circumstances. From short lengths of row, low in plant-population, yields are low. In aggregate these sparsely populated lengths are a feature of considerable economic importance.
Preliminary investigation on the fecundity of premium stallions
Authors: Walton Arthur , Keith Fair T.
Published: March 2009

A Recent statistical survey of the records of premium stallions by Sanders (1) draws attention to the fact that the breeding efficiency of the horse is much below that of the other domesticated animals and that it has apparently declined within recent years. For example, between 1887 and 1889 the average number of mares served by Light Horse stallions and which produced foals was about 59 per cent, of the total mares served. Between 1904 and 1910 this figure had fallen to about 56 per cent, and at the present time is not much above 50 per cent. While this decline may in part be due to the record of infertile services being kept more strictly now than formerly, and perhaps also to the more rigorous conditions to which travelling stallions are subjected, the figures are sufficient to indicate that much loss is actually occasioned by low breeding efficiency and also that there might be considerable improvement on the present standard.
A new method for the determination of total phosphoric acid in soils
Authors: Shrikhande J. G.
Published: March 2009

McLean's shorter method of H2SO4-HNO3 digestion of the soil for total P2O5 failed on some red soils from Ceylon, although Hall's HC1 method gave satisfactory results. The cause of failure of the McLean method was interference by the larger quantities of various bases extracted by H2SO4-HNO3.

After first separating the total phosphoric acid as ferric phosphate, McLean's method produced results closely agreeing with those obtained by Hall's method. Total phosphates were separated by first neutralizing the acids in the soil digest and then precipitating the HC1 solutions of the neutralized product by sodium acetate and acetic acid. On boiling, all the phosphoric acid in the soil extract was separated as ferric phosphate. HNO3 solution of this ferric phosphate when precipitated in the usual way gave a clean yellow precipitate of ammonium phospho-molybdate.

H2SO4-Se served as a good substitute for H2SO4-HNO3 in soil digestions and the results obtained were substantially the same as by Hall's method or by the modified McLean's method. H2SO4-Se digestion has certain advantages, such as the possibility of determining both nitrogen and phosphoric acid on the same soil digest.

When selenium is used as catalyst and the phosphate separated by ammonium acetate and acetic acid, the HNO3 solution of total phosphates produces a white precipitate of a complex ammonium selenito-molybdate along with ammonium phospho-molybdate when precipitated by ammonium molybdate. This defect was eliminated after replacing ammonium acetate by sodium acetate.

Attention is drawn to the unexpected behaviour of selenium compounds of phosphoric acid formed during soil digestion towards the reagents used for precipitating total phosphates.
Observations on the Mineral Metabolism of Pullets
Authors: Common R. H.
Published: March 2009

1. Previous observations on the calcium and phosphorus metabolism of the pullet are confirmed.

2. Calcium and phosphorus retention are shown to be related to the amount of sodium chloride in the food.

3. The extra phosphorus excretion which accompanies egg laying involves no marked concomitant change of the amount of potassium in the droppings. Small concomitant increases in the sodium in the droppings were observed where the food contained only small amounts of sodium and chloride; potassium retention was observed on the succeeding day in every case but one.
Liming as a factor in the amelioration of deteriorated tropical soils
Authors: Turner P. E.
Published: March 2009

1. There exist in Trinidad large areas of deteriorated soils which have been under cultivation with a single short-term crop for generations. It has previously been established that these soils differ but little from those which still retain their fertility in their content of organic matter. By comparison with the latter, however, they are markedly acidic and so deficient in exchangeable calcium that a material improvement in their lime status appears to be a necessary preliminary to their amelioration. An examination has therefore been made of the means by which this may most successfully be accomplished.

2. Determinations of the contents of exchangeable calcium and the pH values of a series of liming experimental plots indicate that:

(a) Contrary to experience in England, finely ground limestone has proved a more efficient soil ameliorant than slaked lime.

(b) Single relatively large applications of lime fertilisers have given more immediate beneficial results than small annual dressings.

(c) The effect of liming appears to have been almost entirely restricted to the depth to which the soil is worked. This is doubtless due to the impermeability and lack of aeration which characterises heavy deteriorated soils.

3. A significant increase in crop yield was obtained only on those plots which were later shown to have been rendered neutral in reaction by liming, and on which the degree of saturation of the top 6 in. of soil has been raised to 80 per cent. This value is comparable with that of the fertile soils of Trinidad.

4. The experience of liming methods gained in Trinidad may be applicable to other areas of alluvial soils under cultivation in the tropics.
Determination of soluble carbohydrates, lactic acid and volatile fatty acids in soils and biological media
Authors: Subrahmanyan V.
Published: March 2009

Methods for extraction, concentration and determination of minute quantities of soluble carbohydrates, lactic acid and volatile fatty acids have been described. Different factors affecting the accuracy of the determinations have been studied and corrections, where necessary, have been suggested.
The value of whole sugar beet in the nutrition of swine
Authors: Woodman H. E. , Duckham A. N. , French M. H.
Published: March 2009

Though it is neither customary nor perhaps desirable to utilise sugar beet for feeding purposes, it is conceivable that circumstances might arise occasionally when a farmer would be desirous of feeding the whole or part of his beet crop. This is indicated by the fact that enquiries as to the value of sugar beet for pigs are received from time to time. During the carrying out of the investigation into the value for pigs of dried sugar-beet pulp and molasses-sugar beet pulp, an account of which work is given in this issue of the Journal (1), the opportunity was taken of making a similar study of whole sugar beet. A dual investigation was made, consisting of a digestion trial under the conditions of the metabolism room and a large-scale feeding trial under ordinary farm conditions. It was hoped that the evidence from this twofold line of enquiry would not only settle the question of the value of sugar beet in the feeding of pigs, but also throw light on the subject of the value of root crops in general for swine.
Blood potassium and haemoǵlobin polymorphism in Indian sheep
Authors: Agar N. S. , Rawat J. S. , Roy A.
Published: March 2009

Blood potassium and haemoglobin types were investigated in three breeds of sheep in India. Both high and low blood potassium types and all three haemoglobin types—A, B, and AB—were found to be present in two of the breeds examined, namely Bikaneri and Corriedale x Bikaneri. Mandia sheep had both potassium types but only two haemoglobin types—B and AB. Haemoglobin B and high potassium types predominated in all the three breeds; this would clearly point to the comparative suitability of these animals for relatively drier parts of India.
Effect of placement of liquid and solid fertilizer on the growth and yield of potatoes
Authors: Holliday R. , Draycott A. P.
Published: March 2009

Three field experiments in 1963–5 compared the effects of three methods of fertilizer application, each at four rates, on the growth and yield of main-crop potatoes. Solid fertilizer was broadcast over the furrows and then concentrated round the seed tubers by splitting the ridges during machine planting. Liquid fertilizer was injected immediately after planting either 2 in below and 2 in to the side (shallow placement), or 6 in below and 2 in to the side of the seed tubers (deep placement). Solid and liquid supplied the same quantity of nutrients.

In two years deep placement of liquid gave larger yields than the solid fertilizer and in all three years larger yields than shallow placement of liquid. Results from growth analysis of the 1963 crop indicated that deep placement of liquid gave the largest yield after a dry period. Growth analysis on an additional experiment in 1964 showed that when the soil moisture deficit was limited by irrigation to 1-6 in, both the yield and nitrogen uptake from shallowly and from deeply placed liquids were similar. However, without irrigation deep placement gave a larger yield and nitrogen uptake than shallow placement. An artificial 'dry climate' emphasized that the magnitude of the response to deep placement was related to the soil-moisture regime. It is concluded that the deepplaced fertilizer was in a region of the soil which remained moist, whereas the shallower fertilizer was in drier soil where it was less available to the potato roots.
The ammonification and nitrification in soil of urea with and without biuret
Authors: Low A. J. , Piper F. J.
Published: March 2009

A laboratory investigation was made of the ammonification and nitrification in soil of pure urea with and without pure biuret and pure biuret alone. The soils ranged from acid (pH 5·1) to calcareous (pH 7·9). The work was done at two temperatures 5 and 25°C. The time between adding urea to the soil and the first analysis was from 1 h to 1 week. The soil moisture contents ranged from the wilting percentage to field capacity. In all work involving urea, ammonium sulphate was used as a standard to compare rates of nitrification.

Biuret had no detectable effect on the rates of ammonification and nitrification of urea. Biuret by itself nitrified in all the soils at both temperatures being slowest at 5 °C in the acid soil and fastest in the calcareous at 25°C.

Neither pH nor temperature appreciably affected the ammonification of urea but both had a marked effect on nitrification. The lower the pH and the lower the temperature the slower the nitrification. Ammonium from urea nitrified faster than ammonium sulphate and on the acid soil only ammonium from the urea nitrified.

The moisture content of the soil only affected ammonification of urea slightly but had a marked effect on the nitrification, the drier the soil the slower the nitrification. The same observation applied to ammonium sulphate.
The lime sulphur-calcium arsenate spray
Authors: Goodwin W. , Martin H.
Published: March 2009

The calcium arsenate-lime-lime sulphur spray has been studied in the laboratory and from the results so obtained it is inferred

(1) That the formation of a stable tricalcium arsenate by precipitation from aqueous solution is improbable. The interaction of calcium hydroxide and dicalcium arsenate results in the formation of a continuous series of basic calcium arsenates which are hydrolysed in aqueous suspension.

(2) That through the formation of such basic calcium arsenates the addition of lime to dicalcium arsenate reduces the amount of arsenic in solution. This reduction is temporary and on exposure to atmospheric carbon dioxide the original solubility of the dicalcium arsenate is restored. The concentration of soluble arsenic in the dicalcium arsenatelime spray will not be as great as in the dicalcium arsenate spray and the risk of spray injury with the dicalcium arsenate spray is therefore reduced when lime is added.

(3) The concentration of soluble arsenic in the dicalcium arsenate and lime spray is reduced by the admixture of lime sulphur with a corresponding reduction of the risk of foliage injury.

(4) The precipitation of sulphur from the calcium polysulphides of the lime sulphur is unaffected by the addition of dicalcium arsenate. The addition of lime may result in a diminution of the amount of sulphur so precipitated but such a reaction is dependent on the rate of carbonation of the free lime on the leaf surface. The fungicidal activity due to the calcium polysulphides is therefore unaffected by the addition of dicalcium arsenate but may be adversely influenced if excess of calcium hydroxide be present.
Variation in the onset of the breeding year in the goat
Authors: Asdell S. A.
Published: March 2009

A series of upwards of 6000 matings of goats has been arranged according t o the month of service and correlated with temperature and rainfall.

The maximum of reproduction is found to be in October, and the minimum in May.

A cool summer produces early oestrus while a hot one has the opposite effect. The August temperature is of paramount importance in this respect.

Rainfall had no effect, on the onset of oestrus in the series examined.

The hypothesis is advanced that most mammals breed only in the spring and autumn because their body temperature may be too high in summer for follicular development.
The determination of nitrates in plant materials
Authors: Pyne Gerald T.
Published: March 2009

1. The Valmari-Devarda method of estimating nitrates (i.e.distillation with magnesium oxide and Devarda's alloy) is unsatisfactory in presence of organic matter. Attempts to make it quantitative under these conditions by modifications of alkali and temperature proved unsuccessful.

2. Two new methods for the estimation of nitrate in plant juices are described. The first depends on the use of Devarda's alloy in cold weakly alkaline solutions, the second on the reducing power of titanous hydroxide, under conditions suitable for use with plant products.
Experiments measuring effects of ammonium and nitrate fertilizers, with and without sodium and potassium, on spring barley
Authors: Widdowson F. V. , Penny A. , Williams R. J. B.
Published: March 2009

1. Thirteen experiments were made with spring barley from 1963 to 1965 on soils overlying chalk. They compared yields at ear emergence and of ripe grain from ammonium sulphate and from calcium nitrate, from sodium nitrate or sodium chloride or both, and from potassium nitrate or potassium chloride. Two rates of seedbed N were tested, though they were different each year, and in 1964 and 1965 N top-dressings were also applied. The amounts of N, K, Na and Mg in the green barley, and of N in the grain, were measured.

greatly increased grain yields in all but one experiment, where the barley followed sugar beet. Calcium nitrate gave larger grain yields than ammonium sulphate in three-quarters of the comparisons, but gave much smaller yields than ammonium sulphate on one light soil in 1964 when much rain fell after the fertilizers had been applied. Grain yields from calcium, potassium and sodium nitrates were nearly the same.

3. Na slightly increased grain yields in three and K in two experiments, but combine-drilled P or PK fertilizers increased them in every experiment.
Studies in mineral metabolism: VI. Comparison of the blood of cow and calf in respect to mineral constituents
Authors: Green H. H. , Macaskill E. H.
Published: March 2009

In the paper “Minimum Mineral Requirements in Cattle,” by Theiler, Green and du Toit (1927), analytical data concerning the mineral constituents of the blood of a calf, born of a cow suffering from aphosphorosis, were recorded, but left over for later consideration.
Studies in mineral metabolism. IX: The phosphorus partition of blood in anaemia of cattle and sheep
Authors: Malan A. I.
Published: March 2009

In cases of anaemia in cattle and sheep, of infectious origin, parasitic origin, or due to simple haemorrhage, the phosphorus partition of the blood reveals an “unknown fraction,” confined to the corpuscles, and evidently nucleoprotein. It is determined by difference between the total phosphorus and the sum of total acid-soluble and lipoid phosphorus. It is associated with the appearance of nucleated red cells (normoblasts and Jolly bodies) and vanishes as they disappear. The amount may make up a considerable proportion of the total P.
Notes on the osmotic pressure of the contents of the stomach compartments of the sheep
Authors: Davey D. G.
Published: March 2009

1. A comparison is made of Δ for the blood of sheep with Δ for the contents of the stomach compartments. It is suggested that the approximate identity of the two sets of values is best explained by the view that absorption takes place from the compartments.

2. A variation of 0·570–0·630 is recorded for Δ for the blood of sheep.
The eradication of weeds in cereal crops by sulphuric acid and other compounds
Authors: Blackman G. E. , Templeman W. G.
Published: March 2009

In continuation of earlier work (2) on the destruction of annual weeds in cereal crops some thirty-four replicated experiments have been carried out during 1934 and 1935 in widely different localities. Besides sulphuric acid, nitric acid, ammonium and sodium hydrogen sulphates and ammonium thiocyanate were tested, while the effect of a wetting agent was also studied.

In every experiment the solution was applied by means of a knapsack sprayer at the rate of 100 gallons per acre. In general at the time of spraying the weeds were in the seedling stage, and the cereal crop not more than 6 in. high. Counts of the weed density were made in order to estimate the degree of control, while in the majority of the trials the yield of the cereal was determined.

Sulphuric acid at a concentration of 9·2 per cent. (1 gm. H2SO4 per 100 c.c.) gave a 90 per cent. control of Brassica arvensis (average of nine experiments) and when a 13·8 per cent, strength was used it gave a 95 per cent, control of Raphanus raphanistrum (average of eight experiments). Nitric acid at equivalent concentrations was slightly but significantly more effective in three out of nine trials for the eradication of these two species. Ammonium hydrogen sulphate (21·6 per cent.), sodium hydrogen sulphate (23·6 per cent.) or ammonium thiocyanate (3–10 per cent.) did not, on the whole, compare favourably with sulphuric acid. Decreasing the concentrations of sulphuric acid by a third resulted in a less effective destruction of Brassica arvensis or Raphanus raphanistrum. This loss of efficiency at the lower concentrations was not corrected by the addition of a wetting agent (Agral 1 at 0·1 per cent.); similar results were obtained for nitric acid.
The digestion of bacterial mucopeptide constituents in the sheep: 2. The digestion of muramic acid
Authors: Mason V. C. , Milne G.
Published: March 2009

1. In experiments with four lambs cannulated in the abomasum and terminal ileum the amounts of muramic acid, diaminopimelic acid and α-amino nitrogen passing through the abomasum, terminal ileum and rectum were compared. While the concentration of muramic acid and diaminopimelic acid was higher in the ileal than in the duodenal dry matter, the ratio of muramic acid to diaminopimelic acid remained fairly constant at about 1·00:0·86 on a molar basis.

2. There was a very significant net absorption of α-amino nitrogen between the abomasum and terminal ileum, but no net absorption of muramic acid between these points. However, less muramic acid passed out of the rectum than passed through the terminal ileum.

3. It was concluded that in the normal sheep bacterial mucopeptide synthesized in the rumen is not digested in the small intestine, but is extensively degraded by bacteria in the caecum and colon.
Experiments on the use of home-grown foods for milk production. IV. Methods of feeding bulky foods
Authors: Blaxter K. L. , French T. H.
Published: March 2009

1. An experiment has been carried out with dairy cows to find whether feeding the same ration in different ways has any effect on milk yield or milk composition.

2. No differential effect on milk yield or milk composition of the three methods of feeding which were used could be demonstrated, in spite of an extremely accurate experimental technique. It was therefore concluded that there is no advantage in increasing the number of meals into which a ration is divided, or spreading the ration over a longer period.