bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of nitrogen, phosphate and potash on the secretion of nectar. Part I
Authors: Ryle Margaret
Published: March 2009

1. Experiments were carried out to test the effects of the three main mineral fertilizers on the secretion of nectar by apple, mustard and buckwheat. Factorial designs were used, and data on plant growth were collected in order to attempt to relate growth to nectar production. Apart from the apple trees the plants were cultivated in clean sand to which known quantities of pure minerals were added.

2.Apple.The mean quantity of sugar per flower was significantly increased by extra potash; phosphate also tended to increase it. At the higher level of potash, nitrogen had significantly increased the crop of apples the previous year; it decreased the nectar yield. Potash increased nectar yield most when its effect on the crop had been small, and vice versa.

3.Mustard. In this experiment the quantity of water supplied to the plants was varied as well as the fertilizers. On the last sampling occasion nectar was more frequently obtained from plants with the lower dose of nitrate than from those with the higher dose. At the high level of water, and with low nitrate, extra potash consistently increased the mean quantity of sugar per flower but with the high level of nitrate it consistently decreased it. The phosphate level had no significant or consistent influence on nectar yield.

Treatments increasing nectar production tended (a) to decrease stem weight and total number of flowers; (b) to retard flower production, probably as a consequence of relatively slower growth; (c) to increase petal length, and (d) to increase the proportion of plants with orange or red pigment in the withering leaves.

4.Buckwheat. Nectar was obtained significantly more frequently from those plants which had received extra nitrate and extra potash. It is suggested that the nitrate effect was due primarily to the senescent condition at the time of sampling of some of the plants with the lower dose, especially those which also had the high level of phosphate, and to the interactions of nitrate with phosphate and potash in respect to nectar production. Such explanations do not account for the effect of extra potash. Extra nitrate and potash always increased the stem weight and number of flower sprays; phosphate had little effect.
Observations on the development of the fleece and follicle population in Suffolk sheep
Authors: Burns Marca
Published: March 2009

Observations were made on four Suffolk lambs from birth to 14 months of age, wool and skin samples being taken periodically. The lambs were on a high nutritional plane and grew well throughout the experiment.

1. There is good agreement between estimates of growth based on body weight, calculated surface area, and expansion of tattooed squares.

2. Fibre Type Arrays were Valley or Plain.

3. Benzene tests showed considerable medullation in the fleeces of all the lambs, mainly in the posterior parts. There were practically none on the shoulder.

4. The weight of keratin produced daily per unit area of skin reached or exceeded the figure given as maximal by Galpin (1948) in only six samples, of which four were grown prior to 1 month old.

5. The follicle population completes its development early, only a few secondary follicles being added after birth. The definitive S/P ratio is 5/, which is similar to the Leicester, and lower than in the Romney breed. The follicle density, although high at birth, is lower than in the Romney or Leicester, after 9 months old. Both S/P ratio and follicle density are higher than in the Blackface breed.

6. The transitory black colour of the birth-coat of Suffolk lambs is due to pigmentation of the tips of many fibres; this may affect any type of fibre from haloes and sickles to histerotrichs. With very few exceptions all follicles cease to produce pigmented fibre at or shortly after birth of the lamb. Large amoebic melanoblasts are present in the skin.
Studies on soil phosphorus III. Phosphorus fractionation as a fertility index in South Australian soils
Authors: Williams Colin H.
Published: March 2009

A simplification of Ghani's method for the fractionation of soil phosphorus has been used to study relationships between soil and plant phosphorus in field and pot-culture experiments.

In pot-culture experiments with red-brown earth soils (pH 5·6–6·1) wheat derived approximately 60% of its phosphorus from the fraction of soil phosphorus soluble in 2·5% acetic acid-1% 8-hydroxyquinoline and 30% from the inorganic fraction soluble in 0·1 n-sodium hydroxide, even although the amount of acetic acid soluble phosphorus present in these soils was only about half that present as inorganic alkali soluble. Very little use was made of organic phosphorus.

In field experiments with similar soils there was a correlation between the percentage phosphorus in the plant material and the acetic acid soluble, the inorganic alkali soluble, and the sura of these two fractions of soil phosphorus. The sum of these two fractions was also correlated with the amount of phosphorus taken up by the crop.

In pot-culture experiments with a wider range of soil types there was good correlation between the total extractable inorganic soil phosphorus and both the phosphorus content of the plant and the phosphorus uptake. Correlations between individual inorganic extractable soil phosphorus fractions and plant phosphorus were influenced by the pH of the two groups of soils examined.
Effective temperature as a measure of environmental conditions for pigs
Authors: McLagan Joan R. , Thomson W.
Published: March 2009

1. Three experiments confirmed the view that losses, poor weight gains and low food consumption were always problems among pigs reared in an open pen in a large uninsulated building in comparison with the better results for pigs reared in wooden ark huts. Pigs in an ark hut with an outdoor run did better than those in one with an indoor run.

2. The effective temperature of the different types of housing was estimated. The differences found were not large but the environment which produced the best pigs had the highest effective temperature.

3. The provision of an insulated, dry floor to sleep on made it possible to rear good pigs in a pen where before they had failed. Woollen jackets did not provide sufficient insulation to affect the growth or health of pigs in a hut or pen.
Studies in grazing management II. The amount and chemical composition of herbage eaten by dairy cattle under close-folding and rotational methods of grazing
Authors: Waite R. , Holmes W. , Campbell Jean I. , Fergusson D. L.
Published: March 2009

1. An attempt has been made to measure the amount of herbage eaten by groups of milking Ayr shire cows when grazing under two different systems, (a) close-folding and (b) rotational.

2. Under close-folding the daily consumption of dry matter varied from 18 to 27 lb. per cow. Long herbage reduced the amount eaten. Considerable increases in the weight of herbage offered resulted in only slightly increased consumption. On good leafy pasture the dry-matter intake was about 24 lb. per cow per day.

3. Under the rotational system the intake was more constant at about 28 lb. dry matter per cow per day. Some abnormally low results were obtained which were associated with the difficulty of obtaining a representative sample of herbage, particularly after grazing.

4. Frequent chemical analysis of the pasture before and after grazing on the close-folding system were made, and the intake of the major grass constituents calculated. A comparison of nutrient intake as calculated from these results with that theoretically required has been made.
Investigations on copper deficiency in plants
Authors: Piper C. S.
Published: March 2009

A water-culture technique has been described which makes it possible to determine with precision the effects on plant growth resulting from the absence of traces of the various heavy metals.

The essential nature of copper for plant growth has been confirmed, and the quantitative data presented show that the addition of traces of copper to a nutrient solution leads to increases of growth of the order of 200–1200%.

The characteristic symptoms produced by growing oats, peas, wheat, Wimmera rye-grass,Phalaris, flax, tomato, subterranean clover, and lucerne in nutrient solutions devoid of copper are described. Copper becomes necessary for normal healthy growth at an early seedling stage and is required so long as active growth is proceeding. Optimum growth of oats was obtained throughout a wide range of copper concentration in the nutrient solution.

Oats grown in a copper-free nutrient solution until the development of acute deficiency symptoms recovered and completed their normal life cycle on the addition of sufficient copper to the solution.

The copper content of oats at various stages of growth has been determined. The proportion of copper in the dry matter of the plant was greatest in the young stages and rapidly decreased as growth proceeded.

The copper content of mature oat plants showing symptoms of copper deficiency was less than 1·0 mg. per kg. whether grown in nutrient solution or obtained from copper-deficient soils. Oats which ceased growth from copper deficiency at an earlier stage of development contained a relatively greater amount of copper in their dry matter.
The composition and nutritive value, when fed to ruminants, of pea-pod meal and broad-bean-pod meal
Authors: Woodman H. E. , Evans R. E.
Published: March 2009

Attention is directed in this paper to the desirability, particularly at the present time, of conserving, for purposes of winter-feeding, the pea-pods that accumulate in large quantities at the factories during the pea-canning season. Conservation on the farm is best carried out by the method of ensilage, young pea-pods, such as are obtained in the factory, giving rise to a very satisfactory type of silage without the use of molasses. Broad-bean-pods, on the other hand, do not lend themselves to successful conservation by ensilage, owing to the fact that they become “slimy” in the process and yield an unpalatable product.

Both pea-pods and bean-pods are conserved in the factory by the method of artificial-drying. One such process is described in the present paper. The final product in both cases is obtained as a fine brown meal. Pea-pod meal, in some respects, particularly in regard to its satisfactory content of protein and lime, has a composition not unlike that of the leguminous hays. The similarity, however, does not extend to the fibrous constituent, pea-pod meal having a very much lower fibre content than the hays.

An outstanding characteristic of pea-pod meal is its richness in sugar, no less than 16·5% of the dry matter consisting of a mixture of sucrose and invert sugar. It is the presence of this abundance of sugar that accounts for the favourable fermentation that takes place when young pea-pods in the fresh condition are conserved as silage.

Bean-pod meal displays the same general features in respect of composition, but is distinctly poorer in lime and sugar than the pea-pod meal. Pea-pods and bean-pods, both in the fresh and artificially-dried condition, contain very little carotene and have, therefore, little or no significance as a source of this vitamin A-precursor in the feeding of live-stock.
Clinical and experimental observations on reproduction in the mare
Authors: Day F. T.
Published: March 2009

1. The length of oestrus in mares varied from 3 to 54 days, although in most cases it was 7–8 days.

2. The length of dioestrus varied from 5 to 30 days, but in most cases was 11–16 days.

3. Ovulation occurred in most cases on the last day of oestrus, but a considerable number of ovulations occurred on the 1st and 2nd days before the end of oestrus, and in a few cases from the 5th day before the end of oestrus to 1 day after the end of oestrus.

4. Artificial insemination of mares was equally effective in the intervals of 24, 48 and 72 hr. before ovulation but was unsuccessful in intervals of 2 and 4 hr. after ovulation.

5. Pregnancy was diagnosed in all mares by rectal palpation on the 23rd day and in one mare as early as the 16th day.

6. The foetus developed in the opposite horn of the uterus to the ovary which ovulated at the onset of pregnancy in five out of seven mares.

7. Ovulation occurred in one mare on the 23rd day of pregnancy.

8. Gonadotrophic hormones had no effect when given in the anoestrous period (November to March).

9. Ovulation was induced in 20–40 hr. in most cases after the intravenous injection of 1000–2000 mouse or rat units of pregnancy urine extract intravenously, provided a fairly mature follicle was present in the ovary at the time of injection.

When this ovulation occurred, the duration of oestrus was shortened.
The movement of potassium in irrigated and fertilized red sandy clay
Authors: Lachower D.
Published: March 2009

The present investigation was intended to furnish information concerning:

(1) The movement of water-soluble and exchangeable potassium in the soil profile after successive fertilizer applications.

(2) The form of potassium—exchangeable, soluble, or non-exchangeable—into which added potassium fertilizer is converted in the soil.

(3) The effect of doubling the fertilizer ration on the absorption of potassium by the soil; and the effect of doubling the ration of irrigation water on the absorption and accumulation of potassium in the soil.

(4) The effect of frequent successive summer irrigation following fertilizer application on the distribution of the three forms of soil potassium.

(5) The effect of fertilization followed by irrigation on soil pH. value.
The fate of manganese sulphate in alkaline soils
Authors: Wain R. L. , Silk B. J. , Wills B. C.
Published: March 2009

1. Experiments have been made to determine the effect of treating alkaline soils with manganese sulphate on the quantities of manganese which can be extracted by N-ammonium acetate.

2. Two soils of known total and ‘extractable’ manganese content were treated with manganese sulphate solution in the laboratory and re-analysed after definite time intervals. In the first of these, a calcareous soil from the College Farm, the extractable manganese decreased for 14 days after treatment, after which time manganese was again liberated, presumably due to a waterlogging effect. The extractable manganese in the second soil, a slightly alkaline soil with a high organic matter content, increased appreciably after treatment and remained at this level for the duration of the experiment.

3. An experiment conducted in the field on a highly calcareous soil showed that the extractable manganese content down to a depth of 12 in., had fallen to its original level only 7 days after treatment. This behaviour is in agreement with the observations of other workers that there is little residual effect from manganese sulphate treatment for subsequent crops. The desirability of performing similar experiments on other soils is suggested.

4. The effect of waterlogging and steam sterilization was to increase the quantities of extractable manganese in the soils examined.

The authors wish to express their grateful thanks to Mr B. S. Furneaux, M.Sc, for the descriptions of the soils investigated, and to Dr N. H. Pizer for his valuable suggestions in the preparation of this paper. They are also indebted to Mr J. Hargrave of the Agricultural Institute, Kirton, Lines, for providing the Bourne Fen soil, and to Mr J. Tinsley, B.Sc., for pH and organic matter determinations.
The effect of herbage allowance on herbage intake and performance of ewes and their twin lambs grazing perennial ryegrass
Authors: Gibb M. J. , Treacher T. T.
Published: March 2009

The effect of herbage allowance on the intake and performance of Scottish Half bred ewes with twin lambs was investigated over the first 16 weeks of lactation. Herbage allowances were defined as g herbage D.M./kg live weight (LW)/day, and were maintained by provision of fresh areas of ungrazed sward each day.

Herbage allowances in the range 25–120 g D.M./kg LW/day were offered on an area of perennial ryegrass (Lolium perenne cv. S. 23). Parturition was synchronized and ewes and lambs were turned out to pasture 1 day after lambing.

Measurements were made of the herbage intake, live-weight change and milk yield of ewes, of lamb growth rates and of the herbage intake of lambs from 10 weeks of age.

Herbage allowance had a significant linear effect on intakes of grass by ewes and lambs. The highest intakes by the ewes were achieved during the second week, and were in the range 23–43 g OM/kg LW/day. Intakes declined, as lactation proceeded, to 19–29 g OM/kg LW/day at week 12. Intakes of lambs were similar in weeks 10 and 12 and were in the range 17–24 g OM/kg LW/day. Allowance had a significant effect on live-weight change of the ewes after the first month and upon final body condition.

There was no effect of allowance on milk yield until week 6. Mean milk yields were 2·3 kg/day at day 14, 1·0–1·5 kg/day at day 42 and 0·7–1·1 kg/day at day 84. There was a positive effect of allowance on growth rates of the lambs after the first month. Mean overall growth rates to 84 days of age were 175–243 g/day.
The carotene content of certain species of grassland herbage
Authors: Smith A. M. , Wang Tung
Published: March 2009

The total nitrogen and carotene have been determined in sixty-three samples of white clover, cocksfoot, rye-grass and timothy taken at different times during the growing season from various localities.

Except for rye-grass, there was more carotene in the leaves and stems than in the heads or flowers. A late dressing of ammonium sulphate increased the carotene content of rye-grass by 55 and 17% in the leaves and heads respectively. The effects of lime and slag on the carotene content of cocksfoot and rye-grass were much less marked and there were no obvious effects due to environment.

The predominant factor in determining both nitrogen and carotene, which were very closely related, was stage of growth. Grazing effected important increases in both constituents.
The role of exogenous plant regulators in the dormancy of onion bulbs
Authors: Abdel-Rahman M. , Isenberg F. M. R.
Published: March 2009

Experiments were conducted to study the effect of plant injection with growth regulators on the dormancy of onion bulbs cv. Elba Globe. Application of abscisic acid induced early senescence of the leaves and prolonged the rest period of the bulbs. This effect was partially overcome by subsequent applications of gibberellin, auxin or cytokinin and totally overcome with the application of a mixture of the three hormones. Maleic hydrazide application prolonged the rest period by inhibiting both sprouting and rooting of the bulbs throughout the storage period. This inhibitory effect was not overcome by the subsequent application of auxin, gibberellin, kinetin, or their combinations. Ethephon application increased rooting of bulbs and partially overcame the effect of abscisic acid on dormancy.
Investigations on the root nodule bacteria of leguminous plants: XX. Excretion of nitrogen in associated cultures of legumes and non-legumes
Authors: Virtanen Artturi Ilmari , von Hausen Synnöve , Laine Tauno
Published: March 2009

The associated growth of peas and different non-legumes (barley, oats, wheat, and potato) was investigated both under sterile conditions and in ordinary pot cultures. In the former case the medium consisted of quartz sand, and in the latter of clay or sandy loam soil, poor in soluble nitrogen. It is shown that nitrogen was transferred from the pea nodules to the non-legumes.

In sterile cultures, where the excreted amino-acids cannot undergo decomposition, oats, wheat and barley utilized only a part of the excreted nitrogen, generally less than 50 per cent. In some instances, however, the barley took up considerably over 50 per cent of the excreted nitrogen. There was an apparent accumulation of aspartic acid in the medium of the associated cultures. In pot cultures, where the amino-acids may have been broken down by contaminating micro-organisms, the transfer of the excreted nitrogen to the potato exceeded 90 per cent.

All experiments show that with increasing ratio of non-legumes to legumes the growth of the peas suffers, obviously from lack of nitrogen. Under these conditions, the excretion from the nodules increases to such an extent that the peas receive only a small fraction of the nitrogen fixed by the nodules. The major part of the carbohydrate material furnished by the pea for the amino-acid synthesis in the nodules is excreted into the medium. This naturally causes disturbances in the growth of the pea.
Ovulation in the ewe
Authors: Anderson James
Published: March 2009

Thirty-one laporotomies, in addition to a number of confirmatory operations, were performed to determine the time of ovulation in the ewe. It was found that (1) ovulation did not occur during oestrus, (2) in ewes with oestrous periods lasting 30 hr. or more ovulation occurred a short time after the end of oestrus and that the time of its occurrence is related to the end and not to the beginning of oestrus, and (3) there is a minimum period of approximately 23–25 hr. before which ovulation does not occur, irrespective of the duration of oestrus.
Fecundity of male rabbits as determined by “dummy matings”
Authors: Macirone C. , Walton Arthur
Published: March 2009

A method of obtaining samples of semen from rabbit males by means of a dummy and artificial vagina is described. The volume of the semen, and the number of spermatozoa per cm. (density) and the total number of spermatozoa in the sample have been measured. The data obtained from these measurements have been analysed under the following headings:

1. Relation between total volume and total number of spermatozoa. With an increase in the total volume of the ejaculate there is an increase in the total number of spermatozoa, but the relationship is not linear. The density of spermatozoa varies considerably.

2. Seasonal variation. Seasonal variation in sperm production is not marked in these data. There is slight tendency for the numbers to be highest in the early part of the year and lowest in August and September when the animal is moulting.

3. Individual variation. In each individual, variation is considerable. Differences between individuals are not marked, but as most of the animals were of low average fertility, it is probable that this result is not typical of male rabbits in general.

4. Effect of successive matings with in a short period. In successive matings the number of spermatozoa diminishes rapidly. As the density is not much affected, the diminution is due to reduction in the volume of the ejaculate.

5. Relation between the number of spermatozoa in the ejaculate and the number in the various sections of the spermatic tract. After a series of samples had been obtained, some males were killed and an estimate made of the number of spermatozoa present in various parts of the tract. From the results it is concluded that on ejaculation the vas deferens is practically emptied and that some sperm in the ejaculate come from the cauda epididymis.

6. Observations on sexual behaviour. The sexual pattern of the male rabbit is described and the relation between sexual stimulation and sex drive is discussed.
Digestibility trials with poultry: VIII. The digestibility of dried molassed sugar-beet pulp
Authors: Halnan E. T.
Published: March 2009

In the process of manufacture of sugar from sugar beet, the sugar is first extracted from the beet by appropriate means, and the wet residue or pulp is then dried and sold for cattle feeding. The composition of the dried pulp or slices differs somewhat according to the nature of the process used in the extraction of the sugar. In the “diffusion” process, in which water is used, the extraction is very efficient, with the result that the sugar content of the dried pulp is low. In the Steffen process, in which press methods are used, a fair amount of sugar is left in the dried residues. In the de Vecchi process the sliced beets are dried before the extraction of the sugar takes place, and a certain proportion of these slices is occasionally marketed on the Continent as cattle food. The characteristic differences between these three types of pulp are shown by analyses given by Fangauf and Waldow(1).
A study of the effect of feeding oils to dairy cows and of the value of the Latin square lay-out in animal experimentation
Authors: Garner Frank H. , Sanders H. G.
Published: March 2009

1. A description is given of an adaptation of the Latin square lay-out to experiments with dairy cows. Experiments were conducted to test the effect of adding various fats and oils to the ration, and since effects were rapidly produced the Latin square technique proved very efficient, experimental errors being rather lower than those usually obtained in experiments with crops.

2. Seventeen separate experiments, including, in all, twenty-one different cows (many of whom were used more than once), were conducted; fourteen of these were short-term experiments with unit periods of 5 days, two were medium-term with unit periods of 10 days and one long-term with 20 days.

3. Palm oil, butter, lard and possibly cotton-seed oil were found to increase butterfat yield, chiefly by raising the butterfat percentage of the milk. Soya-bean, linseed and whale oils were without effect. Cod-liver oil definitely decreased butterfat percentage and butterfat yield.

4. It appears that the beneficial oils are those containing a large proportion of the saturated fatty acids.

5. Experiments with the same oil were not always consistent, and it appears that the effect may vary from cow to cow, and also with the same cow at different times.
Studies in tropical soils: IV. Organic transformations in soils, composts and peat
Authors: Duthie D. W.
Published: March 2009

1. Waksman's simplified scheme of fractionation was used in attempts to trace the organic transformations occurring in some tropical samples of composts, soils and peats.

2. It was found that a useful partition of the nitrogenous substances into hydrolysable and resistant fractions could be effected by boiling with 5 per cent sulphuric acid for 6 hours.

3. Two profile layers of a black calcareous Trinidadian clay soil were compared with two horizons of a prairie soil examined by Waksman & Stevens. The surface layers of both soils were found to be similar in chemical characters, but the lower subsoil layers of the Trinidadian soil gave evidence of a more advanced and profound degree of organic decomposition.

4. Serial soil samples, taken from eight undisturbed natural profiles representative of humid tropical soil types occurring in Jamaica and Trinidad, were similarly examined.
An analysis of the factors determining yields in crosses between semi-dwarf and taller wheat varieties
Authors: Lupton F. G. H. , Oliver R. H. , Ruckenbauer P.
Published: March 2009

The growth and development of two semi-dwarf winter wheat varieties, of two taller varieties, and of random selections from two crosses between semi-dwarf and taller varieties were compared over 2 years. Changes with time of crop dry weight/m2, leaf area index and ear size were expressed as orthogonal polynomial regression coefficients. Significant correlations were obtained between yield, the polynomial coefficients and growth measurements relating to number of tillers and flag leaf area duration, but many of these variables were significantly correlated with each other. Multiple regression equations were therefore calculated expressing yield in terms of the variables. These showed flag leaf area duration and rate of ear growth to be the most important characters determining crop yield. The greatest reduction in total yield variance was obtained by the simultaneous consideration of characters relating to photosynthetic capacity and ear development. The significance of this finding in relation to the relative importance of ‘apos;source’ and ‘sink’ in determining grain yield are discussed.
Analysis of post-weaning growth in pigs
Authors: Smith A. D. Buchanan , Donald H. P.
Published: March 2009

1. The post-weaning growth of 135 litters has been analysed with a view to determining the relationship of certain arbitrary subdivisions with each other. For this purpose, the weight increases during three periods of 28 days have been denned in two ways—first, by age, the periods being 10–14, 14–18, and 18–22 weeks, and secondly, by weight, the periods beginning at 40, 80 and 120 lb. and continuing as before for 4 weeks.

2. When the periods are defined by age, the mean increase per pig per litter is affected by weaning weight, but not by litter size (Table III). The variability of the individual increases becomes greater as the pigs become older and heavier (that is, passing from one period to a later one), but less within a period as the rate of growth increases (Table IV). It was not affected by litter size.

3. The distribution of individual weights became increasingly skew with age. This is regarded as a graphical illustration of the fact that while absolute rate of growth is increasing, initially small animals must fall farther and farther behind (Graph 3).

4. The correlations between the average litter increases in different periods were calculated for litter sizes 6–11. In general, the coefficient for periods 1 and 2 was about 0·4, and for periods 2 and 3 about 0·6 (Table VI). This is interpreted to mean that, when judged by results over the whole time under observation, litters with a high correlation between the increases in weight during short periods are not properly comparable with those with a low correlation. By this method, differences in rate of growth having an important influence on carcass quality may be obscured.
Distribution of copper in the Karaka tree (Corynocarpus Laevigata)
Authors: Pitcaithly N. P. , Worley F. P.
Published: March 2009

Copper has been detected in a large number of plants, and is probably present in very minute amounts in all vegetation. Estimations of copper content of a number of plants have been made, notably by Fleurent and Levi(1), Maquenne and Demoussy(2) and McHargue(3).
The effect of pregnancy on hair growth and shedding in the guinea-pig. (With one text-figure.)
Authors: Strangeways D. H.
Published: March 2009

The effect of pregnancy on hair growth and shedding in the short-haired guinea-pig has been studied. It is shown that during pregnancy the amount of hair produced on defined areas of skin decreases until at the time of parturition and for 2 weeks afterwards practically no hair growth is taking place. This is followed by an increased output of hair substance, and hair production returns to its normal level after 11 weeks.
The Maintenance of Healthy Stocks of Potatoes in England
Authors: Bbyan H.
Published: March 2009

1. An attempt to maintain the health of a stock of Scotch seed Majestic in England is described.

A small stock of seed obtained direct from Scotland was split up into three equal portions A, B, C, which were grown isolated from each other and all other potatoes for three years (1927–9).

A. Remained unrogued.

B. Had all plants showing virus disease symptoms rogued out and the requisite seed saved from the remaining plants when mature.

C. Had a similar quantity of seed saved from ostensibly healthy plants when immature.

2. In a final chequer board yield trial fresh Scotch “stock” seed, which can be assumed to be above the average of ordinary Scottish seed, beat stocks A, B and C significantly. There was no significant difference in the yields from the stocks obtained by the two methods B and C and both stocks beat the mature unrogued stock A significantly.
The effects of drought on barley growth: models and measurements showing the relative importance of leaf area and photosynthetic rate
Authors: Legg B. J. , Day W. , Lawlor D. W. , Parkinson K. J.
Published: March 2009

In a field experiment on the effects of drought on spring barley the crop was protected from rain by automatic rain shelters. Various plots received irrigation at different times to give a range of drought treatments from full irrigation to no irrigation between emergence and harvest. The foliage area, light interception, stomatal resistance and leaf photosynthesis rate of five treatments were measured throughout the growing season, and a mathematical model has related the computed whole canopy photosynthesis to the measured total dry-matter yields at harvest. Hence, it was possible to estimate tha independent influences of drought on radiation interception, efficiency of use of intercepted radiation, and respiration. The analysis shows that for all treatments the decrease of intercepted radiation was the major factor in reducing yield, and it accounted for a loss of 30–40% for treatments that were stressed from the beginning of the season, and of 10–20% for treatments that were stressed after mid-May. Stomatal closure caused a reduction of up to 11% in daily photosynthesis, and the maximum effect was on plants that acquired a large leaf area before being stressed. However, the effect of stomatal closure integrated over the whole season was only 6% or less. Our measurements of internal resistance to carbon dioxide transfer were not precise enough to show significant differences between treatments; but increases of internal resistance, caused by stress, may have contributed to loss of yield.
Results from two barley experiments at Saxmundham, Suffolk, measuring effects of the fungicide benodanil on three varieties, given three amounts of nitrogen at two times 1973–4
Authors: Widdowson F. V. , Jenkyn J. F. , Penny A.
Published: March 2009

Midas, a barley variety very susceptible to brown rust (Puccinia hordei), and two less susceptible varieties (Julia and Mazurka) were given three amounts of nitrogen (50, 100 or 150 kgN/ha) either at sowing (in March), in May, or half at each time. Benodanil sprays were applied to one half of each plot in June and again in July to control brown rust. Brown rust became more severe in 1973 than in 1974 and was most severe on Midas with 150kgN/ha. In 1973, there was most brown rust where all or part of the nitrogen was applied in May, but in 1974 there was least brown rust where all the nitrogen was applied in May, probably because dry weather limited its uptake.

In 1973, when ample rain fell in spring and summer, grain yield was increased more by nitrogen given in May than in March, especially when benodanil was given. In 1974, little rain fell until July and then March nitrogen increased grain yield most whether or not benodanil was given. Top dressing of N (in May) produced a smaller straw yield than seed-bed dressing did in each year.

Benodanil spray much decreased brown rust and increased yield of grain, but not of straw; the increase was greater in 1973 than in 1974, when brown rust was less abundant. Benodanil increased yields of all varieties, but that of the rust susceptible variety, Midas, most. Benodanil increased grain yield more, as more N was given to the barley, and more with N given in May than in March. It increased the amount of N removed by the barley grain, but not by the straw.
Effect of long term water deprivation on body weight and water intake of breeding ewes under semi-arid conditions
Authors: More T. , Sahni K. L.
Published: March 2009

Thirty-nine adult ewes of identical body size and age were randomly taken from the Chokla breed. They were divided into four groups which were allowed water once in 24, 48, 72 and 96 h. Seven ewes from each of the first, third and fourth groups were mated for the first time in the spring and for a second time in winter, so that they lambed in the monsoon and summer season respectively. All the ewes were maintained on uncultivated pasture. Watering once in 72 and 96 h caused body weight loss up to 26%, compared with those watered daily. The ewes which failed to maintain pregnancy lost more than 30% of their body weights due to watering only once in 96 h and there were about 43 and 100% lambing in the first and second breeding cycle of the same ewes. The remaining groups displayed 100% lambing. The water-intake increased significantly in the third month of pregnancy in the group allowed water daily and water consumption was found to be about 13% of body weight, whereas the values for those watered once in 72 and 96 h were 9 and 8% respectively. The water-deprived animals were able to drink up to 32 % of their body weights within 2–3 min. It is concluded that breeding ewes could be watered once in 72 h without any loss of lambing during summer.
Influence of foliar applied chlormequat on radiation attenuation by winter barley canopies
Authors: Green C. F. , Dawkins T. C. K. , Hunter B.
Published: March 2009

Biomass production in barley is determined by the amount of solar radiation absorbed by the foliage (Gallagher & Biscoe, 1978). As incident irradiance per unit area varies little between neighbouring sites and seasons in the cereal growing areas of the U.K. (Monteith, 1978), biomass production will largely be governed by the size of the canopy, the orientation of canopy constituents and the efficiency of conversion of absorbed radiation into dry matter (Green, 1984). Reviewing the literature, Monteith & Elston (1983) have highlighted the constancy of mean seasonal efficiency, concluding that growth is limited by the ability of the stand to absorb radiation.
A comparative method for describing the seasonal distribution of production from grasses
Authors: Corrall A. J. , Fenlon J. S.
Published: March 2009

A standard method is proposed for establishing the seasonal pattern of production for grasses. The procedure consists in recording the yield from grass swards cut every 4 weeks and from which limitations to growth from the supply of water or nutrients have been removed. Four series of plots are harvested in rotation, spaced a week apart so that there is a routine of harvesting a constant number of plots on the same day each week. A statistical analysis is also described enabling comparisons to be made between the grasses under test. An example is given to illustrate the method and the results obtained.
A comparison of gastrointestinal water content and osmolality in East African herbivores during hydration and dehydration
Authors: Maloiy G. M. O. , Taylor C. R. , Clemens E. T.
Published: March 2009

A wealth of information is available concerning the ‘normal’ gastrointestinal mechanisms within various species of herbivores (Alexander, 1962; Church, 1971; Quarterman, Phillips & Lampkin, 1957). In addition, the effect that dehydration has upon the physiology of digestion has also been investigated (Schmidt-Nielsen et al. 1956; Schmidt-Nielsen, 1964; Maloiy, 1972; Macfarlane et al. 1972). This communication presents preliminary observations on the effect that dehydration hasupon gastrointestinal water content, as a percentage of total gut contents, and fluid osmolality (m-osmol/kg H2O). A comparison was made under controlled laboratory conditions between six species of domestic herbivores fed identical diets and exposed to a simulated desert environment
Analysis of yield stability in field beans (Vicia faba L.) in the Northern Province of the Sudan
Authors: Yassin T. E.
Published: March 2009

Ten varieties of field beans, grown in different environments, were analyzed for genotypic stability of their seed yield. The linear responses to the environments were insignificant, but deviations from linearity were highly significant suggesting that the relatively unpredictable component of the genotype x environments interactions was more important in this material than the relatively predictable component. Environmental effects per se were very important in determining differences in mean seed yield. The relatively large deviations from linearity of variety IW may be due to powdery mildew disease. RB 29 was identified as a good yielding and stable variety in the range of environments tested.
Nutrient composition of the produce of the Broadbalk continuous wheat experiment II. Changes occurring during one season's growth
Authors: Chambers W. E.
Published: March 2009

1. In the summer of 1945 samples of the growing crop were taken from eight Broadbalk plots. On all the plots the concentrations of nutrients in all parts of the plants decreased during growth. The compositions of the roots and stems and leaves varied with fertilizer treatment at all times of the season. The nutrient composition of the ears was only slightly affected by fertilizer treatment.

2. The total uptake of nutrients by the crop increased to a maximum and then decreased. The losses of potassium and magnesium from the stems and leaves were particularly large, due to translocation into the ear but there were also net losses of potassium and calcium from the whole plant.

3. The changes which occurred were similar on all plots and the effect of fertilizer treatment on plant composition was always related to the effect at harvest. There was no evidence that the composition of the crop at harvest differed radically from the composition earlier in the season.
Myoepithelial cells in bovine sweat glands
Authors: Goodall A. Myfanway , Yang S. H.
Published: March 2009

1. Spindle-shaped myoepithelial cells with longitudinal myofibrils have been demonstrated in the sweat glands of Ayrshire and Zebu cattle.

2. The cells in both breeds are similar in structure, location and arrangement.

3. Under the polarizing microscope they are birefringent as is characteristic of other fibrillar structures.
Effect of egg transfer on the skin follicles and birthcoats of Finnish Landrace and Soay lambs
Authors: Burns Marca , Ryder M. L.
Published: March 2009

The birthcoats of Finnish Landrace lambs showed a wide range of halo-hair grades but all had strongly checked fibre type arrays, which were either Plain or Valley. Transfer to Welsh Mountain dams reduced the effect of prenatal check, giving fewer sickle fibres and increased halo-hair and/or super sickle A percentage. Transfer to Border Leicester tended to have the opposite effect. Fibre diameter measurements made on skin samples indicated an increase in primary fibre diameter in transfers into Welsh dams, but no difference in transfers into the Border Leicester.

All Soay samples had Grade VII halo-hair density and Plateau or Saddle arrays. Transfer of Soay eggs to Finnish Landrace ewes increased the percentage of sickle fibres mainly at the expense of hairy-tip curly-tips. Skin samples from the transferred Soays indicated reduced primary fibre medullation, and evidence of retarded secondary follicle development.

Thus in both breeds the birthcoat changed slightly in the direction of that of the foster-dam. There was, however, no indication that increased prenatal check was associated with increased foetal size. It is therefore concluded that changes in birthcoat as a result of egg transfer are more probably due to direct effects of the maternal environment than to the effect of foetal size as previously postulated.
Muscle weight distribution in four breeds of cattle with reference to individual muscles, anatomical groups and wholesale cuts
Authors: Charles D. D. , Johnson E. R.
Published: March 2009

One side of each of 51 carcasses of Hereford, Angus, Friesian and Charolais cross-bred steers was dissected and the weights of individual muscles and total carcass muscle were obtained. The percentage distribution of total carcass muscle weight in muscles and in. standard groups of muscles was determined. In addition, the percentage distribution of total carcass muscle weight in wholesale cuts was determined from the weights of whole and part muscles specified as comprising the respective cuts.

Minor breed differences only were found in muscle weight distribution among muscles, groups of muscles and wholesale cuts. Similarity of muscle weight distribution in the different types of carcasses studied shows that carcass shape is not associated with differences in the distribution of muscle weight in wholesale cuts.
The effect of three different growth rates on the chemical composition of the dressed carcass of cattle and the relationships between chemical and dissected components
Authors: Murray D. M. , Tulloh N. M. , Winter W. H.
Published: March 2009

This paper describes the chemical composition of dressed carcasses of Angus steers and relationships between chemical and dissected components of these carcasses. These cattle were grown from 300 to 440 kg at three different rates. The rates were: High (H, 0·8 kg/day), Low (L, 0·4 kg/day) and High-Maintenance (HM, 0·8 kg/day followed by a period during which body weight was maintained constant).

There were no significant differences between treatments in the regression equations for weight of water, protein or chemical fat against left side weight (half carcass). However, weight of ash was significantly greater in the HM group than in the H group. These results are similar to those obtained with dissection data on the right side of the same carcasses.

There were no significant differences between treatments for regression equations predicting dissected composition from chemical composition. The common regressions for each component are as follows:

log y (total side muscle) = 0·282 + 1·061 log × (protein) (Sν,× 3%), (i)

log y (total side bone) = 1·055 + 0·836 log × (ash) (Sν×) (ii)

log y (total side fat) = – 0·380 + 1·076 log × (chemical fat) (Sν,× 4%), (iii)

where all values of × and y are in grams.

Equations (i) and (ii) were used to predict the dissected composition of Angus steers from another experiment in which one group of cattle lost weight. Equation (i) gave useful predictions but equation (ii) did not.
Effect of nitrogen rates, mulching and antitranspirants on water use and water use efficiency of barley (Hordeum vulgare L.) varieties grown under dryland conditions
Authors: Agarwal S. K. , De Rajat
Published: March 2009

Field experiments were made under natural rainfall during the winter seasons of 1972–3 and 1973–4 at the Indian Agricultural Research Institute, New Delhi, to study the soil water use by barley varieties as influenced by nitrogen rates, mulching and foliar application of antitranspirants. Both Ratna and Vijaya varieties of barley had similar efficiency of water use.

Total water use was not much different for various treatments but straw mulch and kaolin decreased evapotranspiration at tillering and pre-flowering stages enabling the plants to use more water at critical stages of grain formation. Application of nitrogen, straw mulch and a foliar coating of kaolin increased the efficiency of water use.
Developmental characteristics of grass varieties in relation to herbage production: 4. Effect of nitrogen on the length and longevity of leaf blades in primary growth of Lolium perenne, Dactylis glomerata and Phleum pratense
Authors: Davies I.
Published: March 2009

The effects of nitrogen treatment on blade length and longevity were studied in primary growth of early and late varieties of perennial ryegrass, timothy and cocksfoot. Reproductive and vegetative tillers were examined in cocksfoot, but in perennial ryegrass and timothy the study was restricted to reproductive tillers, which accounted for a large proportion of the primary growth in these species. Results obtained by a technique which involved repeated recording of tillers were corroborated by those obtained by destructive sampling of tillers.

With respect to the blade length of culm leaves, responses to nitrogen shown by S. 23 ryegrass and S. 48 timothy were greater than those of the early-heading varieties S. 24 ryegrass and S. 352 timothy. However, blade longevity was appreciably reduced by nitrogen in the late varieties whereas the early varieties showed a much lower response.

Implications of these results in relation to the accumulation of senescing material in primary growth are discussed.

The pattern of leaf expansion in vegetative tillers of cocksfoot is discussed in relation to regrowth.