bluuebunny/crossref_metadata_2025 huggingface dataset:
Maize fertilizer experiments in Western Tanzania
Authors: Scaife M. A.
Published: March 2009

Results of 132 maize fertilizer experiments (NP and NPK) carried out over 3 years in Western Tanzania have been grouped to give sixteen ‘response areas’. Responses to N and P were very large in the south-western half of the research zone, where rainfall is fairly well distributed. On granitic soils around Lake Victoria, responses were mainly to N alone. In the drier areas, notably Shinyanga district, responses to both N and P were on average very small. No significant positive responses to K were found, except for one trial in Karagwe district.

It was found that all observed responses to N and P could be accounted for in terms of a generalized two-factor Mitscherlich-Baule yield equation, with constant curvature terms, cn and cv.

Using this equation it is possible to define ‘maximum economic requirements’ of the nutrients N and P for various maize and fertilizer prices and potential yields. The difference between this maximum requirement and the amounts of these nutrients supplied by the soil (given by the Mitscherlich-Baule parameters bn and bp',)represents the optimum rate of fertilizer application, where profit per acre is at a maximum.

Empirical equations are presented for estimating b from soil analysis results for areas not adequately covered by these experiments, but such estimates may not always be accurate.
Studies in the geology and mineralogy of soils: I. A detailed study of a region characterised by diverse rocks and partly covered by glacial drift
Authors: Hart R.
Published: March 2009

1. An account is given of the geology and mineralogy of the soils of a small area characterised by diverse rock groups, which are mainly covered by glacial drift. The topography is also varied. The soils are mainly derived from boulder clay, glacial sands and gravels, and alluvium, the remaining soils being formed on screes and hill-wash. The underlying rocks are lavas of Old Red Sandstone age and sandstones and shales of Carboniferous age.

2. A similarity in mineral content of the soils on glacial material and alluvium is shown. All these soils have a high content of fresh ferro-silicates. The soils on the screes and hill-wash are characterised by their content of rock fragments and iron oxides, but minerals from glacial material are also present, though to a minor extent.

3. The soils on the drift material contain potash, phosphate and lime-bearing minerals.

4. The varied nature of the parent materials has given rise to varied textures in the soils. The soils on the boulder clay are the heaviest, while, the soils on the fluvio-glacial material are very variable.

5. The mineral content of the matrix of the boulder clay is similar to that of the local rocks, only the rarer minerals being derived from external sources.
The action of certain chemical substances on the zoospores ofPseudoperonospora Humuli(Miy. et Takah.) Wils
Authors: Goodwin W. , Salmon E. S. , Ware W. M.
Published: March 2009

1. BothPseudoperonospora HumuliandPhytophihora infestansare extremely susceptible in the zoospore stage to the action of weak solutions of soap or saponin. The zoospores are caused to disintegrate suddenly, apparently by changes in surface tension, within 60 seconds, in solutions containing over 0·1 per cent, soft soap. Those ofP. Humuliare more vulnerable than those ofP. infestans.

2. The fungicidal action of soap and saponin mixed with certain adherent substances was tested on hop plants.

3. The power of adhesion and the fungicidal efficiency of the mixtures were tested by allowing single drops to dry on the surface of watch glasses and by then adding drops of water containing zoospores.

4. Other substances,e.g.aluminium-lime mixture, glycerine, iodine, bromine, were also found to kill zoospores rapidly.
Studies in crop variation: VI. Experiments on the response of the potato to potash and nitrogen
Authors: Eden T. , Fisher R. A.
Published: March 2009

The development is recorded of the series of experiments with potatoes at Rothamsted during 1925–27, designed to examine the quantitative response of yield to varying quantities of nitrogenous and potassic manures, and to test the relative value with this crop of different sources of potash.

While rather precise comparisons were obtained on the qualitative question by means of Latin squares in 1925–26, the reality of the depression ascribable to chloride could not be demonstrated in these years, but became clearly apparent when in the following year, the qualitative experiment was merged with the quantitative one.

In the earlier quantitative experiments, although satisfactory responses were obtained, the precision of the results left much to be desired, since only four replicates could be used. When by merging the experiments this was increased to nine replicates, much smaller responses were clearly measurable.

The large and complex type of experiment finally adopted thus supplied more precise information on both heads than could previously be obtained, and in addition to a more thorough exploration of the different combinations possible.
Factors affecting the yield and quality of milk: I. The age of the cow
Authors: Kay R. R. , M'Candlish Andrew C.
Published: March 2009

1. The variations in production due to age have been investigated with the records of 738 Ayrshire cows for 4380 lactations.

2. Milk and butterfat production increase up to about 7 years of age and then show a decrease.

3. The fat percentage for 3-year-olds is higher than that for older cows.

4. After 3 years of age there is little change in the fat percentage with age that is of any practical significance until advanced ages are reached, when there may be a fall of importance.

5. The increase in production associated with age is probably attributable, in part, to the growth of the secretory tissue of the udder and to body growth in general.

6. Part of the increase may also be due to an improvement in functional activity through use.

7. The tendency for milk to show a slightly lower fat percentage as the cow advances in age is probably due to the fact that as the milk yield changes the fat yield changes in the same direction but at a slower rate.

8. There is little known regarding the influence of very advanced age on production, but it is probable that many cows maintain for a long time the production associated with maturity, and then decline slowly.

9. Heifers with a low fat percentage need not as a rule be expected to test higher on reaching maturity.

10. It is probable that the increase in production with maturity is associated more closely with high initial production than with persistency of production.

11. Correction factors for age are presented.
The influence of different levels of dietary calcium upon egg-shell thickness, with a study of the relationship between egg-shell thickness and porosity
Authors: Tyler Cyril
Published: March 2009

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.
Pyrethrin I and II: Their estimation in pyrethrum (Chrysanthemum cinerariaefolium). II
Authors: Tattersfield F. , Hobson R. P.
Published: March 2009

1. The acid method previously described has been used to evaluate samples of pyrethrum derived from both Swiss and Japanese seed, with equally successful results.

2. A rapid method for the evaluation of pyrethrum by a determination of pyrethrin I is described.
The effect of heat on milk: (A) On the coagulability by rennet. (B) On the nitrogen, phosphorus and calcium content
Authors: Mattick Elfreida C. V. , Hallett Howard S.
Published: March 2009

Milk which has been heated to temperatures varying from 105–209° F. for half an hour differs from raw milk in its reaction to rennet in all cases.

There is no change in the diffusibility of the nitrogenous substances in milk after heating to temperatures varying from 105–209° F. for half an hour.

Heating to 175° F. and above for half an hour appears to reduce the diffusibility of the phosphorus content of milk.

Heating to 125° F. and above for half an hour causes marked diminution in the diffusibility of the calcium content of milk.
Investigations on yield in cereals. VI. A. A developmental study of the influence of nitrogenous top-dressing on wheat: B. A measurement of the influence of disease (“take-all”) upon the yield of wheat
Authors: Doughty L. R. , Engledow F. L. , Sansom T. K.
Published: March 2009

This series of investigations embraces studies of the more important factors, external and internal, which govern yield in field crops of cereals. It has so far dealt with the causes and influence on yield of fluctuations in density of plant population and also with certain inter-field differences of environment. Throughout, an analytical method has been employed, in which periodic observations have been made upon small samples distributed over a representative acre in a field crop. The best size of sample has proved to be a one-foot length of row, i.e. row of plants as seeded by the drill. The basis of this method—a “census” of an acre of corn—has been described and critically examined in an earlier paper (Engledow(1)). Analyses of certain external factors affecting yield have been recorded by Engledow(2) and by Doughty and Engledow(3).
The Decomposition of Green Manures in Soil
Authors: Daji J. A.
Published: March 2009

Four plant materials of widely different origin and age were used as green manures mixed with soil for decomposition studies under laboratory conditions.

Provided the conditions of temperature, moisture, aeration, and micro-flora, are optimal, the decomposition depends upon the chemical constituents of the plant materials. It is shown that the soluble carbohydrates, hemicelluloses and cellulose are the compounds mainly responsible for the loss of total organic matter during decomposition.
Growth cabinet studies into cold-tolerance of Festuca arundinacea populations: I. Effects of low temperature and defoliation
Authors: Thomas W. D. , Lazenby Alec
Published: March 2009

The survival of potted plants of the North African Festuca arundinacea populations syn. 1 and syn. 2 was compared to that of the British cultivar S. 170 following 18 h periods in a growth cabinet at 24 °F, 21 °F and 18 °F. No plants in any of the three populations were killed by the 24 °F or 21 °F treatments but, following the 18 °F treatment, survival of both synthetics was greatly reduced, especially amongst plants that had been cut back to 1 in. (2·5 cm) 6 days prior to the cold treatment. Reduction in tillering and deaths in syn. 1 were both greater than in syn. 2. Both cut and uncut plants of S. 170 survived the 18 °F treatment, their tillering being relatively little affected.

In a subsequent study, survival of syn. 1 and syn. 2 at temperatures decreasing to 16 °F was less amongst plants cut back to soil level than amongst those cut back to 3 in (7·5 cm) or left uncut. No differences were detectable between survival in the two synthetics, nor was there any significant effect, on such survival, of time interval prior to the cold shock.

The results showed close agreement with previous patterns of winter survival of these populations in the field.
Transition from anoestrus in the mare and the effects of artificial lighting
Authors: Burkhardt John
Published: March 2009

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.
The nutritive value for pigs and ruminants of dried penicillin felt
Authors: Woodman H. E. , Evans R. E.
Published: March 2009

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.
Studies of natural herbage of the sub-tropics I. The digestibility of herbage grazed by cattle
Authors: Topps J. H.
Published: March 2009

1. In two continuous digestibility trials carried out in 1960 and 1961, groups of three wether sheep were fed on oven-dried herbage which had been selectively collected from natural pastures during December 1959 to March 1960 and December 1960 to March 1961. The organic matter digestibility and the digestible crude protein content of the herbage and the nitrogen concentration in faeces were measured over periods of 5 days. The fresh faeces of dairy cattle grazing the natural pastures were regularly sampled and analysed. Regressions of organic matter digestibility and digestible crude protein content on faecal nitrogen were evaluated. From these equations and the composition of the dairy cattle faeces the digestibility of the herbage grazed was calculated.

2. The herbage consumed by the cattle had a significantly higher organic matter digestibility and digestible crude protein content than the collected material. This difference, which increased as the season progressed, indicates that dairy cattle became increasingly selective in their grazing as the pasture deteriorated in quality.

3. There was a marked yearly difference in digestibility-faecal nitrogen relationships and in the quality of the consumed forage. The grass eaten in 1959-60 had a higher digestibility and lower digestible crude protein content than in the following year. These differences may be part attributable to a seasonal difference in rainfall.

4. The organic matter digestibility of the grazed herbage ranged from 52·71 to 65·03% and the digestible crude protein content from 3·08 to 7·43% For milk production, the herbage consumed is low in digestible protein in relation to the total amount of digestible nutrients.
The isoleucine requirement of the weanling pig
Authors: Evans R. E.
Published: March 2009

The current standards or estimates of the essential amino acid requirements of swine are based almost wholly on growth trials. These were carried out with groups of three or four pigs fed individually on semisynthetic diets. The trials generally lasted for only 30–35 days since several expensive amino acids were being fed. The main criticism is that the values given were not adequately substantiated by carrying out nitrogen-balance determinations. It is also possible that the nitrogen-retention values might have led to different conclusions from those arrived at on the basis of the growth trials only. The standards must remain tentative until tested with a larger number of animals and until many more nitrogenbalance determinations have been carried out.
Chick rearing: VI. The bacterial syndrome encountered in epidemic bacillary white diarrhoea of chicks (pullorumdisease)
Authors: Mann T. Barton
Published: March 2009

The bacterial syndrome encountered in epidemic bacillary white diarrhoea of chicks (pullorumdisease) is initially one of invasion by faecal type organisms, this is followed by invasion by anaerogenicB. pullorum.

Evidence is presented to show that ostensibly pure cultures of anaerogenicB. pullorum, consist of two organisms, a true aerogenicB. pullorumin symbiosis with an anaerobe, morphologically of thewelchiitype.

Evidence is presented to show that variation in fermentation reactions of ostensibly pure cultures of anaerogenicB. pullorumdepend 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 materialin vivoby the activities of a morphologicallywelchiitype organism.

It is proposed thatB. pullorumexists in one form only, namely, the aerogehic form, and that this organism is a potential pathogen only.
Effect of leaf-roll disease in potatoes on the composition of the tuber and “mother tuber.”
Authors: McLean W.
Published: March 2009

1. Tubers obtained from secondary leaf-roll plants have a lower dry matter content than tubers from healthy plants. The percentage of nitrogen in the dry matter is appreciably higher in the former than in the latter. The difference in dry matter content is sufficiently large in many varieties to characterise leaf-roll tubers. Seventeen varieties were examined.

2. The rate at which the nutrient materials are removed by the young plants from leaf-roll mother tubers is much slower than in the case of plants from healthy mother tubers. This may be a cause of the stunting characteristic of leaf-roll plants.

3. When there is any doubt as to the diagnosis of secondary leaf-roll by the usual symptoms, a determination of the dry matter in the mother tuber two to three months after planting, would serve as a further diagnostic character.
The maintenance requirement of the adult sheep
Authors: Wood T. B. , Capstick J. W.
Published: March 2009

In attempting to interpret the results of two series of sheep feeding experiments, we have been confronted with the fact that the sum of the accepted figure for maintenance requirement and the allowance for the live weight increase produced does not account for the whole of the ration consumed. Sheep averaging 100 lb. live weight folded on swedes in the winter usually eat per week at least 100 lb. of swedes, 7 lb. of hay and 3½ lb. of cake and corn. Such a ration supplies per week about 11½ lb. of starch equivalent.

Sheep fed in this way normally put on per week about 2 lb. of live weight increase, starting from store condition. It is true that figures for the composition of the live weight increase put on by store sheep are somewhat scanty, being practically confined to a series of analyses by Kern and Wattenberg (Journ. Landw. 1880) which give the composition of the live weight increase of store sheep as 44 per cent, water, 45 per cent. fat and 11 per cent, protein, which corresponds to 2200 calories or 2 lb. of starch equivalent per lb.

The requirement for producing 2 lb. of such increase would therefore be 4 lb. of starch equivalent per week.

Measurements of the maintenance requirement of sheep are likewise scanty. There are no recent measurements, but Armsby has recalculated the experiments of Henneberg, Kellner, Hagemann and Wolff, the most recent of which were made in 1893. These workers used two methods. The more scientific method of estimating by respiration experiments the storage of fat on a known ration and arriving at the maintenance requirement by deduction was used by Henneberg, Kellner and Hagemann. Recalculating and averaging their results, which differ widely, Armsby arrives at an average figure of 719 calories per day of net energy for the maintenance requirement of the 100 lb. sheep.
The rôle of aluminium in soil infertility and toxicity
Authors: Hardy F.
Published: March 2009

1. The main results of soil investigations on the rôle of aluminium in soil infertility are reviewed, with particular regard to the physicochemical principles involved.

2. Magistad's conclusion thatsoils or other nutrient media whose reaction values lie within the range pH 4·7and pH 8·5do not contain aluminium in soluble form, and are probably therefore not toxic to plants, is discussed in the light of modern knowledge of the properties of hydrous alumina and its peptisation phenomena.

3. Dialysis experiments which have led to this generalisation are criticised on the grounds that they do not take into account the disturbing effect of dialysis on hydrous colloidal systems, and that dialyser membranes do not simulate plant-cell membranes.

4. Aluminium may possibly penetrate plant-root cells, and, under certain conditions, may be translocated, within the plant body, in at least four different forms, namely, (a) simple ions, (b) more complex colloidal electrolytes, (c) co-ordinated complex anions, and (d) organo-compounds. These may conceivably be interconvertible.

5. Aluminium appears to exert truetoxiceffect only when presented to plant roots as simple ions, or as the more soluble colloidal electrolytes. Apparently, the degree of toxicity varies for different plant species.

6. The reaction conditions of nutrient media and of plant saps doubtless largely decide the form in which aluminium occurs therein. At reactions approaching the isoelectric point of hydrous alumina, toxic effects may never be exerted, although the assignation of a strict reaction-range applicable toallsoils or nutrient media, and toallplant species, is probably inadmissible.

7. Non-toxic forms of aluminium may apparently accumulate under certain conditions at definite tissue regions of certain plants, and may disturb their metabolic processes, disposing the plants to certain diseases.

8. Within the reaction-range at which toxic aluminous solutes cannot exist in soils or other culture media, hydrogen-ions may exert controlling influence on plant growth, and may thus be of major significance in natural plant distribution, and in the behaviour of plants growing in normal agricultural soils.
Potassium and caesium-137 distributions in Angus steer carcasses
Authors: Duggleby J. C. , Seebeck R. M.
Published: March 2009

Seven Angus steers were reared under controlled conditions, slaughtered and their carcasses dissected. Muscles, fat, bones, connective tissues and samples of the steers' diet were measured by gamma spectrometry and the concentrations of potassium and caesium-137 determined. Significant variations in the concentration of each element were found both within and between tissues. Average potassium concentration was about four times greater in the muscle tissue than in the remainder of the carcass. Caesium/potassium ratios were similar in both Caesium/potassium ratios were similar in both bone.

The main conclusions reached were as follows:

(1) The variations of potassium concentrations in muscle may impose limitations on the potassium-40 technique for estimating muscle content of the living animal for scientific purposes, though not necessarily for estimating commercial value.

(2) Differences between animals in caesium-137 content of muscle were fairly consistent over the different muscle groups, and bore some relationship to caesium intake. This indicates that it may be possible to utilize caesium content of a representative muscle to monitor caesium-137 fallout in remote regions of Australia, where milk is not produced.
An improved method for the determination of dissolved oxygen in water
Authors: Subrahmanyan V.
Published: March 2009

The determination of dissolved oxygen by Thresh's method may lead to discordant results because of the loss of iodine, which is carried away by the gas passed through the apparatus during the titration.

A modified method is described, which eliminates the above error and obviates the necessity for making separate determinations of the dissolved oxygen of the reagents used.

Correction for the nitrites present in the water can be made by making separate determination by the Griess-Ilosway colorimetric method.
Studies in mineral metabolism: VII. The unknown phosphorus fraction of calf blood
Authors: Malan A. I. , Green H. H.
Published: March 2009

An unknown phosphorus fraction previously recorded by the authors as frequently present in calf blood, is shown to be nucleoprotein and due to the presence of precursors of fully mature erythrocytes. The same fraction may also appear in small amounts in human blood and in horse blood, and always occurs in very large amount in the nucleated erythrocytes of birds.
Digestibility trials with poultry: II: The digestibility of “weak” and “strong” wheats, and their value for poultry feeding. III. The digestibility of “whole” and “flaked” maize
Authors: Halnan E. T.
Published: March 2009

(1) Digestibility trials with wheats, carried out with White Leghorn cockerels, indicate that “weak” and “strong” wheats are equally suitable as sources of supply of food nutrients for poultry.

(2) In the production of wheat for poultry feeding, yield rather than strength should be the primary aim of the grower.

(3) Further research work on the Katayama method of estimating the digestibility of poultry feedingstufls is indicated.

(1) Digestibility trials with “whole” maize and “flaked” maize indicate that steam cooking by commercial processes considerably increases the digestibility of the food nutrients in maize. (2) The view held that the fowl is akin to the pig so far as its powers of digestibility of low fibre foods are concerned is substantiated by the results of the trials here reported.
Note on the Effect of “Condition” on the Colour of Body Fat in Rabbits
Authors: Hirzel R.
Published: March 2009

Fat colour is of importance in beef produced for English markets because of discrimination against deep yellow fat. The factors at present known to affect colour are genetic(1,4) and those relating to food supply(2,3), but not much is yet known of the various circumstances or natural conditions under which the colour will vary in shade. It was the purpose of this investigation to determine some of these. Rabbits were selected for the preliminary experiments, as, although it is questionable whether the colouring matter in the fat is quite the same as in cattle (3, 5), it is very probably affected by the same conditions. Experiments could be done quicker and cheaper in rabbits than in cattle on which the results could be tested after the pioneer work in the rabbit was completed.
Nutritive value of Lucerne: IV. The Leaf-Stem Ratio.
Authors: Woodman H. E. , Evans R. E.
Published: March 2009

In this paper are brought together a number of data concerning the ratio of the amount of leaf to stem in the lucerne crop, at different stages of growth, and the separate composition of the leafy and stemmy fractions.

It is shown that the proportion of leaf falls off as the crop advances in maturity, and that the rate of decrease of leafiness is greater before budding than during the period from the beginning of budding to early flower. The changes in the leaf-stem ratio largely account for the fall in protein content, the rise in fibre content and the running-off in digestibility and feeding value that take place as the crop passes through the successive stages of growth up to flowering.
Leaf Analysis as a Means of Diagnosing Nutrient Requirements of Tropical Orchard Crops
Authors: Hardy F. , McDonald J. A. , Rodriguez G.
Published: March 2009

1. Attention is drawn to the remarkable dissimilarity between the cacao and the grapefruit tree in their nutrient requirements, indicating that grapefruit is calcicolous in physiological habit. This conclusion is mainly based on a consideration of the results of chemical analysis of representative leaf material produced by trees grown on soil of known chemical and physical characteristics, under the same climatic conditions in Trinidad.

2. The nutrient relationships that obtain between the cacao and the grapefruit tree respectively and the soil in which they are growing have been gauged by means of chemical analysis of representative leaf material.

3. For this purpose, leaf material was obtained from trees growing on the differently manured plots of two large-scale field experiments in Trinidad.
Seed Disinfection: I. An Outline of an Investigation on Disinfectant Dusts Containing Mercury.
Authors: Dillon Weston W. A. R. , Booer J. R.
Published: March 2009

An outline is given of an investigation that has dealt with disinfectant dusts containing mercury, and it is shown that the majority of the inorganic mercury salts are of little value in this respect. Some organic mercury salts have been tested and the result of laboratory and field work suggests that there is a close relationship between composition and fungicidal power. In the series R-Hg-X, where R is a hydrocarbon and X an acidic radicle, the fungicidal power appears to decrease with the increase of the molecule of R. A study is made of the significance of X in the methyl series and the results as they apply to disease control are recorded on a series of graphs.

The specificity of some of the compounds is noted and a brief mention is made of the treatment of seeds other than cereals.

It is suggested that there is no evidence for stimulation in the sense of tonic effect but that instances of better germination, growth and crop yields are due not only to the control of seed-borne organisms but to the preservation of the food reserves in the seed from the attack of soil organisms or mould organisms adherent to the seed.
The relation between inhibitory substances and variability in time to germination of sugar beet clusters
Authors: Battle J. P. , Whittington W. J.
Published: March 2009

Evidence was obtained for the presence of germination inhibitors in the aqueous extract from sugar-beet clusters. A positive correlation was shown between the germination of cress seeds moistened with aqueous extracts from clusters of twenty sugarbeet plants and the germination characteristics of other clusters from the same plants. Inhibition was thus greater in extracts from clusters with poor rather than good germination, and also in extracts from immature clusters or those which had received overhead irrigation. The inhibitory effect was found to be located in the perianth and pericarp tissue rather than in the true seed.
Protein, lysine and feed intake level effects on pig growth
Authors: Blair R. , Dent J. B. , English P. R. , Raeburn J. R.
Published: March 2009

A total of 512 pigs were given from 50 lb live weight one of 16 diets (four lysine levels at each of 12, 14, 16 and 18% protein), at one of four levels of intake. They were killed at 100, 150, 200 or 250 lb live weight and the carcasses jointed in a standard manner and right sides dissected into lean meat, fat, skin and bone.

Mean percentage proportion of shoulder, middle and ham joints in the dressed sides at the four weights was 36·3, 36·4 and 27·3; 35·4, 37·9 and 26·7; 34·5, 39·6 and 25·9; and 33·8, 40·7 and 25·5, respectively. Mean percentage lean meat at the four live weights was 61·5, 59·9, 56·7 and 54·2 and the mean percentage fat was 20·7, 24·4, 29·4 and 32·8.

Carcass quality was influenced significantly by dietary treatment and sex. Increasing the level of protein in the diet up to 16, 16, 14–16 and 14%, respectively, for the four live weight groups gave a significant increase in carcass leanness. Increasing the level of lysine in the diet did not have a very marked effect on carcass composition, while increasing feed intake to the highest level produced fatter carcasses at all weights. Carcasses of males were fatter and with a lower proportion of ham than those of females. Interactions involving dietary treatments and sex were described.

Chemical composition of the m. longissimus dorsi was not altered markedly by dietary treatment or sex but dry matter and intramuscular fat content rose with increasing weight. Protein content of the dry matter remained fairly constant at all weights, while colour and shear value rose with increasing weight but were not significantly influenced by dietary treatment or sex.

The pH values of the m. multifidus dorsi just after slaughter or on the day following were not markedly affected by dietary treatment, sex or weight.
A comparison of field inoculation methods with Cercosporella herpotrichoides (Fron) on spring barley
Authors: Jones D. Gareth , Davies J. M. L.
Published: March 2009

A comparison was made of six different methods of inoculation with Cercosporella herpotrichoidesFron on field plots of the spring barley variety Impala. All inoculation treatments produced significant differences in terms of disease incidence and grain yield compared with the uninoculated controls. Significant differences were found between treatments in terms of disease incidence, disease severity, mean yield/head and 1000 grain weights. The time of inoculation was also found to be significant. The earlier inoculation caused a reduction in yield of approximately 66 % compared with 50 % at the later inoculation. The application of these methods is discussed.
Fertilizer nitrogen and growth regulators for field beans (Vicia faba L.):II. The effects of large dressings of fertilizer nitrogen, single and split applications, and growth regulators
Authors: McEwen J.
Published: March 2009

The largest mean responses to nitrogen ranged from 2·1 cwt grain/acre in 1966 (2 cwt N/acre) to 3·6 cwt grain in 1968 (1–5 cwt N/acre). Responses to the largest dressings were increased by dividing them, the increases ranged from 0·2 cwt grain in 1968 to 4·0 cwt grain in 1966.

In 1968 1·5 cwt N applied in late May increased grain yield by 5·5 cwt, more than the response to any other amount applied either to the seed bed or as a divided dressing. Removing the growing point of the plant at the 4-leaf stage promoted tillering but lessened yield by 5·4 cwt grain. Removing the growing point of the plant after flowering increased yield by 2·1 cwt grain in 1966 and lessened it by 1·7 cwt grain in 1967.

CCC (2-chloroethyltrimethylammonium chloride) had no visible effect on growth and lessened yield by 1·9 cwt.

B9 (N-dimethylaminosuccinamic acid) greatly affected growth and shortened stems by as much as 30%, depending on how much and when it was applied.

B9 had inconsistent effects on yield. Without fertilizer nitrogen, it increased yield by 2·5 and 2·6 cwt grain in 1966 and 1968 but decreased it by 2·1 cwt in 1967.

The main effects of B9 on the components of yield were to increase the number of stems and pods/acre and lessen 1000 grain weight. Plants given B9 in 1968 produced half a million more grains/acre than untreated plants. 1·5 cwt N had similar effects to B9 on the components of yield in 1968. Stems and pods/acre were increased, but there was also a small increase in 1000 grain weight. Plants given 1·5 cwt N produced half a million more grains/acre than plants not given N. A further1·5 cwt N lessened number of stems/acre but this was more than compensated for by an increased number of pods/stem, leading to a further increase of 160000 grains/acre. The effects of season were large and exceeded the effects of any of the treatments.
A critical study of the failure of a long-term calcium and phosphorus balance experiment with laying hens
Authors: Jenkins N. K. , Tyler C.
Published: March 2009

A long-term calcium and phosphorus balance experiment with laying hens is described.

The cumulative balances of calcium and phosphorus over a whole year were seen to be physiologically impossible.

Results from other workers using short term balancescouldbe equally impossible and a similar situation has recently been noted in balance experiments with ruminants.

The techniques employed in the experiment were, therefore, investigated in detail.

Only systematic errors could be responsible and it was found that the most likely source of such errors was (a) the spilling of food on to the floor or into the water bowl, and (b) failure to collect all the droppings.

These errors only become apparent in long-term experiments and are more pronounced when diets containing high levels of calcium and/or phosphorus are fed.
Reduction of nodule numbers and growth, produced by the addition of sodium nitrate to lucerne in sand culture
Authors: Thornton H. G. , Nicol Hugh
Published: March 2009

A sand-culture experiment with inoculated lucerne was made to test the effect of increasing doses of sodium nitrate upon the yield and nitrogen content of tops and roots, and upon the number and development of nodules. The pots were divided into six series receiving from 0 to 10 gm. of sodium nitrate per pot containing 12 kg. of sand.

There was no correlation between yield or nitrogen content of the lucerne, and the dose of nitrate.

The number of nodules, though unaffected by 1 gm. of sodium nitrate, was progressively decreased by the stronger doses.

The length of nodules was reduced about 30 per cent, by 1 gm. of sodium nitrate, and decreased progressively with stronger doses.

Nodules were found to show a definite relationship between their overall length and the volume of contained bacterial tissue. Using this relation, the mean volumes of bacterial tissue per nodule and per pot for each series were calculated. The reduction effected by nitrate was far greater when measured in this way, owing to the small contribution of bacterial tissue derived from nodules less than 1·5 mm. in length.
The relative importance of plot variation and of field and laboratory sampling errors in small plot pasture productivity experiments
Authors: Bartlett M. S. , Greenhill A. W.
Published: March 2009

An investigation of the relative importance in small plot pasture productivity experiments, of plot variations and of field and laboratory errors in sampling and subsampling for percentage dry matter and percentage nitrogen figures, revealed little advantage from duplicate sampling or subsampling in reducing the experimental error, which was due mainly to plot variation.

The effect of sampling errors was of even less importance in the estimation of the actual yields of dry matter or of nitrogen.
Studies on Azotobacter in Malayan soils
Authors: Altson R. A.
Published: March 2009

These observations have shown that the strains of Azotobacter occurring in certain Malayan soils are unable to initiate growth on standard media, except after a lag phase of considerable duration. Evidence has been obtained which suggests that this inability is not necessarily an indication of a scarcity of the organisms in the soil used as an inoculum, but may be due to factors associated with the composition of the culture medium.

In particular the strains of Azotobacter developing from these soils are checked by the presence of calcium carbonate in the medium. They will grow well in a medium in which calcium chloride replaces calcium carbonate, but equally well where the medium contains but traces of calcium.

These strains can tolerate a wide range of hydrogen-ion concentration extending on the acid side to pH. 3·6. Their existence invalidates the use for these soils of all such microbiological tests of lime requirement as make use of Azotobacter as indicator.
Incomplete Latin squares
Authors: Yates F.
Published: March 2009

A description is given of the statistical procedure appropriate for the analysis of a Latin square having missing the whole of one row, one column or one treatment, or one row and one column, or either and a treatment. These are the only types of incomplete Latin squares (except those which can be dealt with by the missing plot technique) for which a neat statistical analysis is possible.

It is shown that incomplete Latin squares of these types give unbiased estimates of error and are therefore valid experimental arrangements. They are consequently likely to be of use when the experimental material is such as to preclude the use of a complete Latin square owing to the fact that the number in one or both of the natural groups is one less than the number of treatments to be tested.
Investigations in crop husbandry. III. Effect of time of application of sulphate of ammonia to wheat
Authors: Garner F. H. , Sanders H. G.
Published: March 2009

1. Over a period of six years seven field experiments were carried out to study the effect of the time of application of sulphate of ammonia to autumn-sown wheat.

2. Three experiments were located on light gravelly soil which had been farmed highly for some years, and in those three cases sulphate of ammonia decreased yield, irrespective of time of application; the reduction in yield was of the order of 10 per cent. and is ascribed to more lodging and greater incidence of “foot-rot”.

3. Three experiments were located on heavy clay soil in poor condition; in these sulphate of ammonia gave percentage increases in yield of 18, 20 and 7.

4. Evidence is produced that early dressings of sulphate of ammonia do not affect germination or plant establishment, but that they tend to increase tiller formation by the end of February.
A method for pelleting small amounts of purified diets
Authors: Dewar W. A.
Published: March 2009

Purified diets prepared from finely ground constituents such as starch, casein, gelatine, cellulose, etc., are not readily acceptable by poultry. This is probably due to their powdery nature, for Coates, Kon & Shepheard (1950) found that chicks grew faster when fed a granulated purified diet than when this was fed unprocessed. Granulation was accomplished by mixing the diet with about a third of its weight of water, pressing the resulting paste through a no. 8 sieve and drying the granules at 40 °C.
The value of artificially dried grass, silage made with added molasses and A.I.V. fodder in the diet of the dairy cow and their effect on the quality of the milk, with special reference to the value of the non-protein nitrogen
Authors: Watson S. J. , Ferguson W. S.
Published: March 2009

An experiment has been carried out with dairy cows to measure the value of artificially dried grass, silage made with added molasses and A.I.V. fodder (silage made with mineral acid in quantity sufficient to bring the pH of the mass to between 3·0 and 4·0) in the diet, on the yield and quality of the milk. A preliminary period of 3 weeks when all cows were on the control diet was followed by an experimental period of 17 weeks. There were four treatments: a control ration consisting of hay, roots and concentrates; one in which artificially dried grass replaced part of the concentrates; a third in which molassed silage was fed; and a fourth including A.I.V. fodder. There were originally five blocks of four cows each, the four treatments being randomised in each block, each block of cows standing together in the cowshed to eliminate any possible effect of position. One block went dry after 8 weeks, but the remaining four blocks completed the experiment.
Advanced sugar–beet seed
Authors: Longden P. C.
Published: March 2009

A technique is described for speeding germination of monogerm sugar-beet seed. The optimum treatment was four cycles of wetting seed with its own weight of water and storing it in a sealed container for 24 hours before drying for 48 hours. The number of cells per embryo was doubled, seedlings emerged approximately 2·5 days sooner and seedling shoot weight was increased by 31 to 53%.
Manganese deficiency in peas and other crops in relation to the availability of soil manganese
Authors: Heintze S. G.
Published: March 2009

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.
Experiments on the use of home-grown foods for milk production. V. The protein requirements of growing dairy heifers
Authors: Blaxter K. L. , Price H. A.
Published: March 2009

1. The changes which have occurred in the nutrition of young dairy stock are discussed. It is emphasized that any food shortage of a farm affects young cattle before the rations of the cows are reduced.

2. An estimate of minimum protein level is developed using Mitchell's (1926) method.

3. An experiment designed to show the optimal level of protein in the ration for growing stock showed a difference between this minimum estimate and the optimal. Some considerable economy in protein can, however, be effected in Wood & Woodman's (1936) standard is the one normally used to calculate rations.

4. The growth of young cattle on protein supplemented wartime dietaries of straw is shown to be below that of heifers fed the rations more normal in peace time.

5. Stunted cattle undergrown by 7–8 months when 18 months to 2 years old have been found. This has been attributed to the effects of wartime rations.
Long term effects of fertilizers on grassland: III. Effects on some soil properties
Authors: Heddle R. G. , Simpson K.
Published: March 2009

Effects of N as ‘Nitro-chalk’, P as superphosphate, and K as KCl and K2SO4 on ‘available’ P, K and Mg were examined over 14 years. The area was under grass/clover regularly cut 6 times a year.

Soil pH was maintained by annual applications of ‘Nitro-chalk’ supplying an average of 4 cwt CaCO3 and 174 lb N per acre. Superphosphate supplying 43 lb P per acre per annum increased available P (modified Morgan method) appreciably even on plots where more than this quantity was taken off in herbage. Applied N also consistently increased available P. It was thought that this was because P in the root system was rapidly mineralized. Applied K consistently reduced available P because of increased uptake in cut herbage, with no apparent increase in root P for mineralization.

The amount of available K in soils which received no added K was fairly constant over the period for a given N treatment. About 40 lb/acre/annum of K was released by weathering.

There was a very marked interaction effect between rates of N and K fertilizers on available soil K, the large increase in available K where K fertilizer but no N was applied being considerably reduced with increasing N rates. These effects directly reflected uptake of K in cut herbage.

Residual values of applied P, K and Mg on the respective ‘available’ nutrients were considerable and persistent.

Available Mg was reduced by increasing rates of fertilizer N and by fertilizer K.
The influence of energy intake on plasma levels of glucose, non-esterified fatty acids and acetone in the pregnant ewe
Authors: Davies P. J. , Johnston R. G. , Ross D. B.
Published: March 2009

Forty cross-bred ewes were individually fed from the end of week 13 of pregnancy to parturition on two diets whioh were designed to provide intakes of metabolizable energy above (treatment El) and below (treatment E2) the maintenance requirement of the non-pregnant ewe.

Energy intake had no significant influence on birth weight of single lambs but twin lambs from ewes on treatment E1 were 25% heavier than twins from ewes on treatment E2. A net loss of body weight occurred between week 13 of pregnancy and the day following parturition in all groups of ewes. These losses represented 5 and 10% of body weight in ewes carrying singles on treatments E1 and E2 respectively. In ewes carrying twin lambs losses represented 11 and 16% of body weight on treatments E1 and E2 respectively.

Levels of plasma N.E.F.A. and acetone were used to characterize the state of nourishment of ewes at 16, 18 and 20 weeks pregnant. Values obtained indicated that ewes carrying one lamb on treatment El were ‘moderately’ undernourished. Ewes carrying one lamb on treatment E2 and those carrying twin lambs on treatment E1 were undernourished to a similar degree characterized as bordering between ‘moderate’ and ‘severe’. Ewes carrying twin lambs on treatment E2 and all those carrying triplets were ‘severely’ undernourished.