bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of paraformaldehyde on the fermentation quality and feeding value of ryegrass and lucerne silages
Authors: Cook J. E. , Wilkins R. J. , Wilson R. F.
Published: March 2009

Crops of perennial ryegrass and lucerne were each ensiled without additives and after the addition of paraformaldehyde to provide about 0·1, 0·2 or 0·4% HCHO/t crop fresh weight. The ryegrass and lucerne silages were offered ad libitum to sheep in separate experiments of identical design.

All theryegrass silages were well preserved with low pH values, the level of butyric acid was very low and ammonia-N comprised less than 8% of total N. The lucerne silage made without additive had a pH of 5 and acetic acid comprised the major part of the total fermentation acids. Ammonia-N comprised over 12% of total N. All levels of paraformaldehyde addition restricted fermentation in both crops and led to an increase in the proportion of total N which was insoluble in hot water.

Voluntary intake of organic matter (OM) was higher for the lucerne than for the ryegrass silages but digestible organic matter (DOM) intake was higher for the ryegrass. Intakes of OM and DOM were not significantly affected by paraformaldehyde treatment. The addition of paraformaldehyde significantly depressed apparent digestibility of OM and cellulose with the ryegrass but had less effect with the lucerne. Nitrogen digestibility was significantly depressed in both crops at all paraformaldehyde levels. Paraformaldehyde addition resulted in increased faecal N output and decreased urinary N, but retention of N was not significantly affected.

The lack of response in feeding value to paraformaldehyde treatment may have been due to the relatively high intake and N retention of the untreated silages which were fairly well preserved.
The manuring of sugar beet
Authors: Boyd D. A.
Published: March 2009

Information on how growers actually manure their crops is available from the Survey of Fertilizer Practice, carried out by the Provincial Soil Chemists of the N.A.A.S., in collaboration with Rothamsted. These data indicate that, taking into account the nutrients in farmyard manure, the average amounts of nitrogen and potash applied are not far from the optimal amounts suggested by experiment, whilst phosphate dressings are on the average at least double requirements. This may be due in part to the fact that few compounds are available with a low ratio of phosphate to other nutrients.

Except in one or two factory areas the use of salt on sugar beet is still very limited.
Nitrogen requirement of sugar beet
Authors: Holmes M. R. J. , Devine J. R.
Published: March 2009

Seventy-four field experiments on the nitrogen requirement of sugar beet were made in eastern England in. 1966 to 1974. Considerable differences in sugar yield response to nitrogen were found between the six soil types used, and these differences were found (on five of the six soils) to be related to sugar yield. Nitrogen response was large on chalk and limestone soils in Lincolnshire, intermediate on East Anglian boulder clays and least on East Anglian chalk and light drift soils. On the lighter soils (limestones, East Anglian chalks and light drifts) nitrogen response was greater with high summer rainfall than with low. Fenland silt soils were very high yielding, but nitrogen response was moderate.

Optimum nitrogen rates differed between soils, in the range 100 kg/ha on East Anglian chalks and light drifts to 180–200 kg/ha on Lincolnshire chalks and limestones.
Chemical treatments for increasing the digestibility of cotton straw: 2. Effect of ozone and sodium hydroxide treatments on the digestibility of cell-wall monosaccharides
Authors: Ben-Ghedalia D. , Shefet G.
Published: March 2009

The digestibility of cell wall (CW) monosaccharides of diets containing as 50 % of their OM, untreated, sodium hydroxide and ozone-treated cotton straw (CS), was studied in sheep cannulated in the rumen and at the duodenum with simple cannulae.

CS contributed the major part of the dietary cell-wall glucose, xylose and uronic acid in the three diets. The digestibility of the diets' CW glucose was 38·2, 66·6 and 50·2 % for the untreated, ozone and NaOH-treated CS-diets, respectively. Ozone and NaOH treatments significantly increased the digestibility of cotton straw CW glucose by 108 and 42%, respectively. The highest digestibility of CW xylose in the whole diet was obtained in the NaOH treatment: 43·4% as compared with 19·1 and 31·2% in the untreated and ozone-treated diets. The calculated values of CW xylose digestibility in CS were lower than those of CW glucose. Ozone remarkably increased the degradation of CW uronic acids. The calculated value for ozonated CS was 68·7%, 4·09 and 1·47 times higher than in the untreated and NaOH-treated CS.

Irrespective of diet, the digestibilities of the minor CW sugars, i.e. arabinose, galactose and mannose, were high, and their degradation was largely completed in the rumen. The contribution of the hindgut flora was expressed mainly in degrading the residues of the potentially digestible CW glucose and CW xylose.

The digestibility values of ADF-cellulose and those of CW glucose were compatible, whereas those of hemicellulose (determined as NDF-ADF) and CW non-glucose polysaccharides (NGP) were clearly different. The digestibility of NGP was 16·8, 36·6 and 43·2% for the untreated, ozone and NaOH-treated CS, respectively. It is suggested that those values more closely represent the digestibility of the ‘true hemicellulose’ fraction.
Field response of poppies (Papaver somniferum L.) to lime application on acid krasnozems in Tasmania
Authors: Temple-Smith M. G. , Wright D. N. , Laughlin J. C. , Hoare B. J.
Published: March 2009

In two field experiments, ground limestone (2·5–20 t/ha), dolomite (4·25 t/ha) and gypsum (3·75 t/ha) were applied to acid krasnozems (Forthside, pH 5·6 and Elliott, pH 5·1), and poppy capsule and morphine yields, leaf nutrient contents and soil chemical properties were measured.

Capsule and morphine yield increased more than two-fold at Forthside as the pH in the surface soil (0–150 mm) increased from 5·6 to 6·1, and by 30-fold at Elliott where the pH increased from 5·1 to 6·0. Capsule morphine concentration was depressed by high rates of ground limestone at both sites but maximum morphine yields of 15·7 kg/ha at Forthside and 11·3 kg/ha at Elliott occurred at the highest rate of ground limestone. Gypsum did not increase yield at Elliott, but at Forthside the gypsum and ground limestone treatment of equivalent calcium content increased yields to the same extent.

The lowest yields at each site were associated with calcium concentration in the leaves at flowering of less than 1% and marginal or high amounts of extractable soil Al at Forthside and Elliott respectively. Concentrations of Ca, P and Mo in leaves were increased by lime applications but leaf concentrations of N, P, Mn, B and Mo on low yielding plots were considered to be in the normal range.

Poppy yield responses to liming were attributed primarily to alleviation of aluminium toxicity but the effects on yield of reductions in soluble Al and increases in available Ca were confounded by application of ground limestone.
Seed vigour in field beans (vicia faba L.) and its influennce on plant stand
Authors: Hegarty T. W.
Published: March 2009

Twenty-one stocks of spring and •winter types of field bean were sown in April 1975 and 59 stocks of spring bean cv. Maris Bead were sown in March 1976, to investigate the relationship between seed germination and seedling emergence in the field. Laboratory germination percentage proved to be a very poor indicator of emergence in the field whereas the seed leachate conductivity test was a more useful guide. Even at recommended sowing rates low plant stands are shown to be a likely cause of yield loss and it is suggested that the conductivity test should be used to identify seed stocks of low vigour so that sowing rates of such stocks can be increased. It is recommended that the conductivity test be carried out as a useful adjunct to the standard laboratory germination test.
Predicting dry weights of pigeon-pea plants from non-destructive measurements
Authors: Hammerton J. L.
Published: March 2009

Seven non-destructive field measurements were made on 1270 pigeon-pea plants varying widely in age, size and plant type, before determining their dry weight. The non-destructive measurements were generally highly correlated with one another, and were all significantly correlated with total, total above-ground and structural dry weights. In one experiment dry weights were best predicted by a multiple regression using stem diameter, length of longest branch and number of branches as predictors. Field height and stem diameter were the best predictors in a second trial. It is suggested that dry weights can be estimated by taking certain measurements at regular intervals, simultaneously sampling a number of plants to determine the best predictive equation. Where it is unnecessary or impracticable to do this, stem diameter appears to be the best single index of dry weight.
Allozymes of phosphoglucoisomerase (PGI) in cultivars of barley (Hordeum vulgare L.)
Authors: Gilliland T. J. , Tinman J. , Camlin M. S.
Published: March 2009

The 65 spring and 14 winter cultivars of barley on the 1981 U.K. National List were examined electrophoretically for allozyme variants of phosphoglucoisomerase (PGI). Two different banding patterns were observed, a ‘fast’ and a ‘slow’ migrating type. With the exception of six spring cultivars in which the ‘slow’ type was found, all the cultivars were classified as ‘fast’. F2 progeny of crosses between ‘fast’ and ‘slow’ plants were used to interpret the banding patterns as resulting from the dimeric isozymes of two alleles (allozymes) each producing a triple band pattern, the faster two bands of which were considered to be ‘secondary’ or artefact bands. With the notable exception of Dragon and its sister line RPB 1115–75 all of the other ‘slow’ cultivars and breeders' selections were found to have the ‘slow’ cultivar Midas in their breeding history. Midas was bred using material from three ‘fast’ cultivars and a γ-ray mutant strain, the irradiation which produced this strain being regarded as the likely cause of the ‘slow’ isozyme. Unlike all the other cultivars tested, Midas was found to be a mixture of genotypes comprising 73% ‘slow’ and 27% ‘fast’ plants, a ratio which was most probably due to founder effects caused by the breeders' selection programme. In the light of the present investigation and other reports it is concluded that it is not an uncommon occurrence to find plants with different electrophoretic banding patterns within inbred cultivars.

This result has serious implications for cultivar registration as there is a possibility of selecting electrophoretically distinct plants from within existing registered cultivars. It is concluded therefore that the protection afforded to plant breeders under Plant Breeders' Rights schemes could be seriously threatened by the use of electrophoretic characters for cultivar registration except in some specific incidences where it may be possible to apply appropriate safeguards. The implications for plant breeders of the existence of isozymes of PGI, of possibly different efficiencies, within commercial cultivars of the genus Hordeum are also discussed.
The Effects of Plant Density, Spatial Arrangement and Time of Harvest on Yield and Root Size in Carrots
Authors: Salter P. J. , Currah I. E. , Fellows Jane R.
Published: March 2009

Four experiments were carried out over a 2-year period to investigate the effect of plant density and spatial arrangement and the time of lifting on yield and root size of carrots. Plant arrangement was varied by growing the plants in 1-, 2-, 3-, 4-, 5- and 10-row systems in beds with rows 12–5 and 37–5 cm apart. With each row arrangement crops were grown at target densities of 108, 323 and 537 plants/ma. There were three times of harvest. Total root yield was not significantly affected by plant arrangement or, in three out of the four experiments, by plant density but yields progressively increased with later harvests at all density levels. Yields of canning-size roots (20–30 mm diameter) were influenced by plant density and time of harvest and there were highly significant interactions between these variables on canning root yields. Highest absolute yields were obtained from the latest harvests from the medium and high plant density treatments; with the lowest density treatments the highest yields of canners were obtained from the earliest harvests. Mean root weight was significantly affected by plant density and harvest time. Row system effects on mean root weight were shown to be largely accounted for by differences in percentage seedling emergence and hence the plant density obtained under the different row system treatments and a possible reason for this effect is discussed. The relationship between mean root weight and plant density was not affected by the pattern of plant arrangement in these experiments. Total root yields were shown to be related to cumulative potential evapotranspiration from sowing rather than to chronological time. It is concluded that with the range of row systems used in these experiments, row spacing had little effect on root yield but confirmed previous work that plant density and time of harvest were the most important variables controlling mean root size and hence the yield of roots of any particular size grade.
The early weaning of pigs: II. The performance up to 56 days of age of pigs weaned at 8, 14 and 20 lb. live weight
Authors: Smith H. , Lucas I. A. M.
Published: March 2009

Groups of pigs were weaned at 8, 14 and 20 lb. live weight from each of seven litters. Each of the twenty-one groups was housed separately and selffed a 30% protein diet ‘A’ up to 25 lb. live weight.

From then until 56 days of age each group was selffed a 22% protein diet ‘B’.

Weight at weaning had no significant effect on age at 40 lb. live weight, but weights at 56 day old of 46·5, 50·2 and 47·7 lb. for pigs weaned at 8, 14 and 20 lb. respectively tended to favour weaning at 14 lb. (P < 0·10).

Pigs weaned at 8, 14 and 20 lb. each required 25, 16 and 6 lb. respectively of expensive diet ‘A’ to reach 25 lb. live weight. To grow from 25 to 40 lb. live weight they each required 30, 28 and 27 lb. of diet B, and this trend in favour of the pigs weaned at heavier weights was significant at P < 0·05.

These results are discussed in relation to the system of early weaning.
Plane of nutrition and starch equivalents
Authors: Blaxter K. L. , Graham N. McC.
Published: March 2009

1. Experiments with two sheep are described in which energy retention was measured at different levels of food intake and the losses of energy incidental to food consumption measured.

2. Attainment of reasonably stable values for energy losses occurred after 72 hr. of fast. On realimentation stable values were not attained until 10 days had elapsed. Methane production was resumed relatively slowly.

3. The accuracy of the mean estimates of energy retention was high, and duplicate determinations of metabolism after lapses of time gave excellent agreement.

4. It is shown that the assumption of linearity of the relationship between energy retention and food intake expressed as metabolizable energy is incorrect.

5. An exponential relationship between energy retention, and food intake was employed to describe the data. This resulted in a reduction of the residual sum of squares compared with a linear regression.

6. It is shown that net energy values (starch equivalents) measured by Kellner, Armsby and Forbes have entirely different meanings, and that the correction employed by Wood reflects these facts.

7. The exponential relationship has been generalized to take into account body-size variation and has been examined as far as it affects concepts of efficiency of food utilization, and of nutritional plane.

8. Nutritional plane has been rigidly defined in such a way that it is independent of body size and of food quality, and it enables net energy values to be predicted at other planes of nutrition once the net energy value at one nutritional plane is known.

9. A simple and rational scheme for the feeding of livestock to take into account the decline in net energy value (starch equivalent) with nutritional plane has been devised.

10. Analysis of the energy losses in relation to nutritional plane shows that losses of energy in faeces, urine and as heat per unit food ingested tend to rise with increasing nutritional plane. Methane losses fall. These results suggest that the prediction of net energy values from measurement of energy losses in faeces, or from estimates of metabolizable energy, can give rise to extremely unreliable results.

11. The results have been discussed in relation to previous work in this field. It is pointed out that the exponential relationships employed are a convenient method of describing a very complex situation and facilitating its analysis.
The effect on yield and leaf area of wheat of applying nitrogen as a top-dressing in April or in sprays at ear emergence
Authors: Thorne Gillian N. , Watson D. J.
Published: March 2009

Nitrogen, at the rate of 0.5 cwt./acre, was applied to winter wheat as an April dressing of nitrochalk, or as eight sprayings of 2% NH4NO3 solution applied either to the soil or to the leaves at about the period of maximum leaf area, before and during ear emergence. All three methods of nitrogen application caused similar increases in yield and nitrogen content of grain. April nitrogen gave a greater yield of straw than the later dressings.

Late nitrogen application caused a small increase in leaf area index, first noticeable one week after ear emergence and persisting for another four weeks. L.A.I. of plots that received nitrogen in April was much larger than that of the other plots at the period of maximum leaf area, but by four weeks after ear emergence it was less than that of plots receiving the late nitrogen. Shoot number per metre and leaf area per shoot were increased by early nitrogen, but only the latter was increased by nitrogen applied at ear emergence.

Leaf area duration after ear emergence was the same on all nitrogen-treated plots and the yield of grain divided by L.A.D. was nearly constant for all plots.

Applying nitrogen late, after an April dressing, did not prevent the rapid fall in L.A.I. from the high value reached at the period of maximum leaf area and caused no greater increase in yield than when applied in the absence of an April top-dressing. A single urea spray applied in early June increased yield to the same extent as the ammonium nitrate sprays.
Grazing studies on the Guadalcanal Plains, Solomon Islands. 2. Effects of pasture mixtures and stocking rate on animal production and pasture components
Authors: Watson S. E. , Whiteman P. C.
Published: March 2009

Animal production was compared on three pastures, Brachiaria mutica (para), B. decumbens (signal) and Panicum maximum cv. Hamil (hamil) each sown with a common legume mixture of Centrosemapubescens (centro), Macroptilium atropurpureum cv. Siratro, and Stylosanthes guianensis cv. Endeavour (stylo), at four stocking rates, 1·8, 21·87, 31·86, and 41·85 animals/ha, over 4 years on the GuadalcanalPlains, Solomon Islands.

Mean live-weight gain per head over the four stocking rates and 4 years on para pastures was 01·847, on signal pastures 01·838, and on hamil pastures 01·828 kg/head/day. Mean production per hectare at the optimum stocking rates were: para at 3.6 animals/ha, 607 kg; signal at 31·86 animals/ha, 442 kg; hamil at 21·87 animals/ha, 362 kg/ha/year.

The high stocking rates of 31·86 and 41·85 animals/ha caused the hamil pastures to decline to the stage where they were destocked in the 4th year of grazing.

Superior production on para pastures was not simply related to green dry matter (GDM) on offer. In the 1st year of grazing, GDM was highest in hamil pastures, but in the 2nd year highest in para, and in the 3rd year mean yields were similar in all pastures, but were very low at the 31·86 and 41·85 animals/ha stocking rate in the hamil pastures.

Para pastures maintained highest legume contents. The quadratic relationship between live-weight gain/head and legume content was significant over all pastures and stocking rates. Live-weight gain (LWG) per head increased up to 15% legume content, after which there was little change. Yield of green leaf, percentage green leaf, and sward bulk density did not appear to be related to LWG/head. Para pastures had lower values for all these components than the other pastures.

Chemical factors contributed to the higher animal production from para pastures. Para leaf maintained consistently higher in vitro dry-matter digestibility values. Na content of para averaged 01·812%, whereas other species were 01·801 to 01·802%, and below the critical level (01·805%) for animal intake. N and S in leaf material, and Cu in total tops were also consistently higher in para grass.

Results of this grazing trial suggest that selection of grass species on the basis of quality including dry-matter digestibility and mineral content, on ability to persist with increasing stocking rate, on compatibility with legumes, and on growth habit are more important than selection for dry-matter yield.
Game domestication for animal production in Kenya: an analysis of growth in oryx, eland and zebu cattle
Authors: Carles A. B. , King J. M. , Heath B. R.
Published: March 2009

Least-squares estimates of the parameters of the Bertalanffy growth equation, adjusted for six sources of variation, were obtained for oryx, eland and zebu cattle.

Values for asymptotic weight were lower than the mature weights normally given for the species, particularly eland and cattle, owing to management constraints. The figures for females brought into the project were considered the most representative of the species in general. For this category of oryx, eland and zebu cattle respectively, the estimates were as follows: the coefficients of growth rate were 0·136, 0·112 and 0·114; asymptotic weights (W∞) were 146, 277 and 395 kg; and ages at maturity (0·98 W∞) were 33, 41 and 39 months. For females born on the project estimates of birth weights were 14·5, 24·1 and 28·7 kg; and of ages at zero weight were 3·55, 3·80 and 5·18 months prepartum, for oryx, eland and zebu cattle respectively.

When differences in size, and therefore metabolic rate were discounted, oryx grew at 3·2, eland at 3·1 and zebu cattle at 3·4 g/kg W∞0·75/day. Comparison with mean values for water turnover (ml/l0·82/day) on the same project revealed that oryx used about one third of the water required by eland and cattle, for the same amount of growth (g/kg W∞/day).

Significant sources of variation for W∞ were species, sex, and mode of entry into the project (capture or birth), all at P < 0·005. Season of birth was also significant at P < 0·01, with oryx born 2 months before a wet month achieving the largest W∞ whereas the highest average growth rate occurred when birth was 1 month before a wet month. The only significant source of variation obtained for growth rate was year of entry (P < 0·005).
Nodulation and nitrogen accumulation in field beans (Vicia Faba L.)
Authors: Igwilo N.
Published: March 2009

The effects of plant population density, defoliation and removal of pods and apical buds on dry matter, nodulation and nitrogen accumulation in field bean (Viciafaba L.) were investigated in the field in 1973 and 1974.

In 1973 seed yield, dry matter and nitrogen accumulation were similar at 50 and 150 plants/m2 while in 1974 40 plants/m2 was significantly different from 80, 120 and 160 plants/m2 which were similar in these attributes. At similar densities, these crops generally had similar leaf areas and nodule weights/m2 during the early pod-filling period while at earlier growth stages leaf area and nodule development were greater at the higher plant population densities. Leaf area and nodule weight per plant were positively correlated as were absolute growth rate per plant and nitrogen assimilation rate per unit weight of nodule.

Substantial leaf removal reduced weight but not the nitrogen assimilation rate of nodules determined from plant nitrogen content. Leaf removal did not significantly reduce dry matter but reduced nitrogen yield by reducing seed yield provided that the removed leaves were accounted for.

Pod removal reduced dry-matter and nitrogen yield as well as nitrogen assimilation rate of nodules. Pod removal, however, substantially increased number and weight of nodules. Most of these late-formed nodules were located on the older parts of the lateral roots. Removal of the shoot apex had minor effects on nitrogen yield but reduced nodulation towards the completion of pod-filling.
On estimating lactation yield
Authors: France J. , Dhanoa M. S.
Published: March 2009

is generally used to describe the lactation curve in cattle, where yn (kg) is the average daily milk yield in the nth week of lactation (n = 1, 2, 3, …, N), a is a scale parameter, and b and c are shape parameters. The model was first proposed by Wood (1967) and is widely used in practice to describe the lactation curve for fat, protein, lactose and wholemilk production; it has also been used as a basis of a mathematical model for poultry egg production (McNally, 1971). Having estimated a, b and c by regression analysis, the total lactation yield Y (kg) can then be calculated as
Experiments on the treatment of parasitic gastritis in sheep and lambs
Authors: Wood W. A.
Published: March 2009

The results of these experiments are, on the whole, disappointing, since they have failed to reveal a reliable treatment for parasitic gastritis of sheep other than that caused by H.contortus, but they do confirm the experiments of other workers in that there are several drugs available which are more or less effective against this worm. Of these perhaps copper sulphate would seem to be in many ways the best for general use, since it is cheap and safe, and can be easily given either dry in capsules or in solution. Better results are obtained when two doses are given, and probably the interval of 7 days between the doses could, with advantage, be shortened to one or two days. The addition of sodium arsenite did not, in these experiments, increase the efficacy of the copper sulphate.

Carbon tetrachloride, given in 12 c.c. doses would seem to be effective againstHaemonchus. In such doses it is rather expensive, and although in these experiments toxic symptoms were not observed, deaths from smaller doses have been recorded by others.

Tetrachlorethylene (Nema) given in capsules containing 5 c.c. gave, in most cases, good results againstHaemonchus, and except in Sheep 10 reduced the egg count very considerably. It did, however, cause considerable constipation, and in a few instances post-mortem examination revealed some inflammation of the small intestine. The administration of a laxative with or shortly after the Nema therefore appears to be indicated.
Studies on the storage of potatoes. III. The composition of the atmosphere in a potato clamp
Authors: Crook E. M. , Watson D. J.
Published: March 2009

The CO2concentration in the atmosphere of a potato clamp varied between 0·06 and 0·86%. The sum of CO2and oxygen concentrations remained approximately constant at 21%. The CO2concentration increased with time from December to April. This was attributed to increase in the rate of respiration of the potatoes caused by rise of temperature. Wind blowing in the direction normal to the face of the clamp reduced the COa concentration, presumably by causing external air to flow through the clamp coverings. A multiple regression of CO2concentration on temperature of the potatoes at the time of sampling, and on the mean component of wind velocity normal to the clamp face estimated over a period of 3 hr. before the time of sampling, accounted for 64% of the variance between sampling occasions.

Unsaturated compounds were detected in the clamp atmosphere by absorption in bromine; the concentration of these, expressed as ethylene, varied between 0·004 and 0·025%.

The magnitude of CO2accumulation and oxygen depletion in the clamp atmosphere was too small to produce effects of practical importance on the storage behaviour of the potatoes. If the unsaturated compounds were ethylene, the concentration present was sufficient to cause appreciable retardation of sprouting.
Studies on soil phosphorus. II. The nature of native and residual phosphorus in some South Australian soils
Authors: Williams Colin H.
Published: March 2009

A study of residual phosphorus in soils resulting from the use of phosphate fertilizers has been made, using a simplification of Ghani's method for the fractionation of soil phosphorus.

In cultivated soils all the residual phosphorus was extractable by successive extractions with 2·5% acetic acid-1% 8-hydroxyquinoline and 0–1 N-sodium hydroxide, and practically all had remained in the inorganic form; very little, if any, change in organic phosphorus was recorded as a result of the application of superphosphate.

In pasture soils (uncultivated) the application of phosphatic fertilizers brought about an increase in both inorganic and organic phosphorus and, in addition, some of the applied phosphate may have entered a form not extractable by the two extractants. The increase in organic phosphorus was not directly proportional to the amount of phosphate applied, as were the increases in the extractable inorganic fractions. It tended to approach a constant value, irrespective of amount and nature of the phosphate applied.
The effect of thermal stress on the acid-base balance of the Ayrshire calf
Authors: Bianca W.
Published: March 2009

1. Two 4-month-old Ayrshire calves were subjected in a climatic room for periods of 2½–4½ hr. to an atmosphere having a temperature of 35° C. and an absolute humidity of 34 mg./l.

2. This treatment resulted in an increase in respiration rate, a decrease in carbon dioxide tension and carbon dioxide combining capacity of the venous plasma, an increase in the lactic acid concentration of the venous blood and an increase in the pH of the urine. The pH of the venous plasma showed only a slight tendency to increase.

3. It is concluded that thermal panting under the conditions described caused a carbon dioxide deficit which was just compensated for by the excretion of alkali by the kidneys, and that this compensation was not substantially influenced by the production of lactic acid resulting from an increased activity of the respiratory muscles.
A survey of beef production in west wales, 1943–8 Part I. Regional production
Authors: Phillips R.
Published: March 2009

1. The structure of the cattle population (4 June returns), as well as of cattle sales to the Ministry of Food, have been illustrated.

2. The trends in cattle production show the definite changes from that of the traditional storestock rearing to that of milk selling.

3. A considerable part (38·2%) of the total graded animals slaughtered for beef are the ‘wastage’ animals from the breeding and dairying herds.

4. Reference has also been made to the high proportion of ungraded cows (36·7% of the total cows) purchased by the Ministry. The ungraded cattle, however, are only 17% of the total sales. On the other hand, the ungraded ‘wastage’ cattle contribute 90% of the total ungraded cattle.

5. More heifers than steers were sold for slaughter, and it has been shown that the average live weight of the graded steers is nearly 224 lb. heavier than that of the heifers.
The effect of nitrogenous fertilizer on the seed yield of the Navy bean (Phaseolus vulgaris)
Authors: Wilkes J. M. , Scarisbrick D. H.
Published: March 2009

Interest is increasing in the Navy bean (or baked bean) as a breakcrop from cereals in southern England. As little experimental work has been carried out on the fertilizer requirements of this crop in the U.K. we undertook a trial in 1973 to investigate its response to four levels of nitrogen.
Studies on the metabolism of fowls: II The effect of activity on metabolism
Authors: Deighton Thomas , Hutchinson J. C. D.
Published: March 2009

An investigation of the metabolism of a number of Light Sussex cockerels has shown that there exists a rhythm in the metabolism during fasting amounting to about 9% as between morning and night observations, the former being the higher by the percentage stated.

Two methods were adopted to exclude the effect of variation in the activity of the birds at different times of day. In the first, the birds were artificially stimulated during the normal period of repose in such manner as to give periods of approximately equal activity by day and by night. In the second, the movements of the birds were recorded by a system of “point scores”, and regression equations were deduced from a large number of such experiments so as to make it possible to reduce the metabolism observations to a basis of zero activity.

The results obtained by these two methods of procedure were in good agreement with one another.

The metabolism in thestandingposition is 40–45% above that in the sitting position, a figure considerably above that for the increase of metabolism as between the lying and standing positions usually found in quadrupeds, while at the moment of rising the heat output may occasionally be trebled, but averages about cent per cent above sitting. The former of these observations is of importance in estimating food requirements as our experiments show that generally speaking rather more than 12 out of each 24 hr. period is spent standing when the birds are kept in cages. It follows that the sitting metabolism must be increased to allow for this when the figure is being used for computation of rations. The large heat increase on rising to the standing posture is of such short duration as to exert little influence on the mean metabolism over a 24 hr. period.
Experiments on cutting potato tubers
Authors: Bell G. D. H. , Gilson M. R. , Dillon Weston W. A. R.
Published: March 2009

1. Field experiments on the use of cut ware setts with the potato varieties Arran Banner, King Edward and Majestic have shown that with proper handling no loss in plant establishment need result. When the cut setts are planted at the same distances as whole setts, there is liable to be a reduction in the yield per acre because of the lower yield per plant, but the actual rate of increase may be increased considerably by cutting because of the larger number of plants obtainable.

2. No benefit has been found from the practice of dusting the cut surfaces of tubers of Majestic with slag, lime or ashes, while adverse effects resulted from the use of a fungicide and alum.

3. The exposure of cut setts to drying conditions lowers their resistance to attacks by micro-organisms, and encourages the breakdown of the tuber flesh by bacteria of the carotovorum group.

4. In general, the use of certain fungicides, either directly on the cut surface, or as a means of moistening sack coverings, is not to be recommended because of the adverse effects of the fungicide on the natural resistance of the live tissue of the tuber flesh.
The statistical basis of selection in animal husbandry: Part I. Studies on life performance of brood sows: an analysis of variance and covariance of progeny born and reared
Authors: Olbrycht T. M.
Published: March 2009

Conscious selection is the prime means of keeping the useful qualities of domestic animals at the level they have attained, and of improving them. Valuable economic qualities mostly show the polygenic type of inheritance and therefore continued selection can improve them by sorting out those genes in a herd or breed which are.most desirable for the breeder At the presenttime there is probably not one breed in existence with quantitative characters brought to the homozygous condition. It is the great genetic variation present in breeds which enables selection to be effective in bringing out desirable economic characters.
Factors affecting the digestion of oesophageal fistula samples and hay samples in nylon bags in the rumen of cattle
Authors: Playne M. J. , Khumnualthong W. , Echevarria M. G.
Published: March 2009

Factors affecting the nylon-bag technique, for examination of digestion in the rumen of extrusa and hay samples of low nutritional value, were studied. Effects of: the method of placement of bags in the rumen; saliva in extrusa; drying and milling techniques; a second-stage digestion with acid-pepsin solution; sample size; and losses of particulate matter through bag cloth were studied. Digestion of dry matter (d.m.) and cell walls after 12, 24, 48, 72 and 168 h in the rumen were used to indicate treatment effects.

Attaching bags with nylon cord to a weight was a better method than enclosing them in perforated jars in the rumen which restricted digestion. Drying technique had little effect on digestion, although frozen extrusa was digested more than oven-dried feed, especially in samples of Heteropogon contortus. Chewing of forage was sufficient to obtain maximum rates of digestion. Milling extrusa through 1 or 2 mm screens did not increase digestion. An extra period of digestion in acid-pepsin solution increased digestion of feed samples more than that of extrusa, but the effects were small. It reduced between-bag variation slightly, but did not alter the significance of differences between treatments. The effect of sample size on digestion was small. Sample weight (3, 6 and 9 g) was kept proportional (42 mg/cm2) to bag cloth area.

Digestion of d.m. after 24 h reflected digestion of cell walls. Digestion of cell walls was faster in grasses than in legumes. The higher digestibility of legumes was due to solubilization within 24 h of the greater amounts of cell contents found in legumes. Cell contents were only partially solubilized, and up to 10 g per 100 g original d.m. were not removed. Losses of particulate matter averaged 4·6% (range 0·5–10·6%). Losses were high when samples were finely milled (1 mm screen) but varied between species. Pore aperture of cloth was 25 μm. Methods for determining loss and correction of digestion data for such losses are given.
Effects of Date of Sowing on Overwintered Onion Varieties in Pembrokeshire
Authors: Allen E. J. , Jones J. L. , Salter P. J.
Published: March 2009

Data are reported from a 3-year study of the effects of date of planting on yield of overwintered onions. Delay in sowing from mid-August to late September increased plant losses during the winter and decreased yields of ware-size onions. Effects were most severe in early maturing varieties.
The porosity of egg shells, and the influence of different levels of dietary calcium upon porosity
Authors: Tyler Cyril
Published: March 2009

1. An experiment was performed to consider the porosity of egg shells, and the influence of different levels of dietary calcium upon this factor.

2. A method was devised for measuring porosity under standard conditions, and the values so obtained are referred to as porosity coefficients.

3. The low calcium diet soon led to the cessation of egg production. The few eggs laid showed a tendency to increasing shell porosity as the end of laying approached. On the average these shells had much higher porosity coefficients than shells produced on a normal calcium diet.

4. The high calcium diet had no apparent ill effects on two birds, but the other two laid many abnormal eggs. Porosity coefficients in this group were, on the average, lower than in the normal calcium group, but not significantly so. Egg production was as good as on a normal calcium diet.

5. The porosity coefficients were significantly higher in period 2 than in period 1, when birds were fed the normal calcium diet throughout; egg production also fell in the second period.

6. Eggs other than the first in a clutch do not differ in porosity, but the first egg has a significantly lower porosity coefficient than the remainder. A possible explanation of this is suggested.
On the behaviour in the field of small grain obtained by premature harvesting
Authors: Hatcher E. S. J. , Purvis O. N.
Published: March 2009

1. By premature harvesting, as early as 5 days after fertilization, dwarf grains are obtained which will germinate readily and produce normal plants, even though grain size may be only 10% that of fully developed grain. Such plants tend to attain the same final size as those from mature grain. This paper deals with the growth under field conditions of dwarf grain with regard to survival during the winter, and final yield.

2. Pot cultures with vernalized winter and spring varieties of rye, wheat, and barley have shown that the high growth rate characteristic of dwarf grain is not confined to the vegetative phase of growth, but is also manifested after the ear has developed. The fact emerges that dwarf grain can be successfully vernalized.

3. A field trial is described using three size classes of grain (mature, medium, dwarf) with mean grain weights of 33·93, 23·56 and 10·23 mg. respectively. These were sown (i) at sowing rates of 2 and 3 bushels per acre, and (ii) at uniform spacings of approximately 200 and 300 grains per 9 ft. row. A subsidiary experiment with spacing of 1 ft. was also carried out.

4. All classes of grain germinated well and survival during the winter was uniformly high in the equally spaced plots; with the close spacing of the dwarf grain at 2 and 3 bushels per acre (plots 11 and 12) percentage survival was somewhat reduced.

5. The effect of grain size and spacing on time of flowering was negligible.
Seed disinfection: IV. Loss of vitality during storage of grain treated with organo-mercury seed disinfectants
Authors: Brett C. C. , Weston W. A. R. Dillon
Published: March 2009

Failures of cereal crops are occasionally reported, the seed having been dressed with an organo-mercury seed disinfectant and the failures attributed to the dressing. It should be noted, however, that prior to the introduction of the organo-mercury seed dressings similar crop failures had often been recorded, and in many cases failure had been attributed to the dressing which had been applied, or alternatively, to the conditions under which the treated grain had been stored.

Reduced germination during storage is common to all agricultural and horticultural seeds, but although the interaction of the factors involved is complex it is generally recognized that for satisfactory germination to be maintained over the maximum period of storage the following conditions should be observed:

(1) The seed should be of relatively high initial germination.

(2) The moisture content of the seed should approximate to the average for that kind.

(3) Storage temperature and humidity should both be relatively low and not subject to wide fluctuation.

(4) Ventilation should be adequate.
Readily soluble manganese of soils and Marsh Spot of peas
Authors: Heintze S. G.
Published: March 2009

1. From an examination of thirty-five soil samples collected in Furneaux & Glasscock's survey of pea soils of the Romney Marsh area of Kent it was shown that the Marsh Spot disease of peas is more closely related to soil reaction than to soil series or soil texture. The disease was not found on any acid soil but was present on most of the alkaline soils.

2. Most of the Romney Marsh soils contained appreciable amounts of free oxides of manganese and of salt-soluble manganese. The soils with Marsh Spot contained less salt-soluble manganese than those on which peas were free from the disease, but this relation depended essentially on the contrast between acid and alkaline soils. Within the alkaline group of Romney Marsh soils, however, analyses for salt-soluble manganese did not always distinguish between contrasted soils; three of the five alkaline soils on which peas were free from the defect were low in salt-soluble manganese.

3. A single extraction with normal calcium nitrate proved as effective as Steenbjerg's series of leachings with normal magnesium nitrate in characterizing the soils. Dilute acids dissolved more manganese than salt solutions. Citric acid gave higher results through reducing the oxides of manganese. The acid-soluble manganese was not related to the occurrence of Marsh Spot.

4. Soils on which oats suffered from Grey Speck disease and sugar beet from “Speckled Yellows” contained little or no salt-soluble manganese. Applications of manganese sulphate, which controlled the diseases in the field, appreciably increased the salt-soluble manganese in the soils.

5. Peas grown in pot cultures in manganese-deficient soils and in a sand-bentonite mixture developed Marsh Spot. Addition of manganese sulphate increased the manganese content of the seeds, especially in sand-bentonite, and controlled the disease.
Studies in soil cultivation: VIII. The influence of the seed bed on crop growth
Authors: Russell E. W. , Mehta N. P.
Published: March 2009

The main conclusions that can be drawn from these field experiments to compare the effect of different methods of preparing the seed bed on the crop's growth are:

(1) Crops germinate faster on the looser seed bed prepared by a Rototiller than on the more compact ones prepared by a plough or a grubber. The total number of plants that germinate is, however, the same for all treatments unless the land is too foul with weeds, when higher germination is obtained on the cleaner plots.

(2) Cereals tend to ripen a little sooner on land that has been ploughed than on land that has been either rototilled or grubbed, but in most years this effect if present is very small.

(3) The shape and the weight of the mangold root seems to depend on the seed bed. The roots were longest and thinnest on the deep-ploughed plots and were always squatter on the shallow-tilled than on the deep-tilled plots. The roots were heaviest on the deep-ploughed plots and lightest on the rototilled plots. On the rototilled and the grubbed plots the depth of tillage had no effect. The plants on the shallow-grubbed plots seemed, however, to have no reserve of strength, for they could not make better growth if given more room, while those on the deep-grubbed plots could make some use and those on the ploughed or rototilled plots appreciable use of extra space.

(4) Weeds tend to accumulate on the rototilled and the grubbed plots since neither grubbers nor rotary cultivators carrying tines mounted on a horizontal shaft can bury weeds and weed seeds in the way that the plough can. If the land is fairly clean and in good heart this probably does not matter for several years, but it prevents either of these from completely displacing the plough.

(5) A subsidiary result that emerged from these experiments is that if a thin crop is given a nitrogenous top dressing, the fertilizer may benefit the weeds more than the crop.
Seed disinfection: III. Experiments on the germination of peas. Seed protection by the use of disinfectant dusts containing mercury
Authors: Brett C. C. , Weston Dillon W. A. R. , Booer J. R.
Published: March 2009

In a previous paper(1) reference was made to the subject of seed disinfection, in particular to an investigation on disinfectant dusts containing mercury. It was shown that by the use of certain of these dusts the common seed-borne diseases of cereals (excluding the loose smuts of barley and wheat) could be controlled. The present observations record further work, chiefly greenhouse and field studies, that has been done on green peas. This crop would appear to be of increasing economic importance, since in the past ten years the acreage devoted to it has increased by approximately 49 per cent. Its successful cultivation is often much influenced by climatic and soil conditions, particularly during the first few weeks after sowing. If adverse weather conditions follow, poor germination may result although the seed sown may have been viable and not necessarily diseased. Failures of such a type are usually associated with the rotting of the ungerminated seed in the soil, but from the same bulks, samples sown under more favourable conditions may germinate well and produce a satisfactory crop. Ogilvie (2,3,4) finds that in the Western Advisory province Ascochyta Pisi and Mycosphaerella pinodes are two causes of the early failure of pea plants, and that “pea sickness” is associated with a strain of the eelworm Heterodera schachtii and with foot-rot caused by various species of Fusarium. Premature dying-off of the plants is accompanied sometimes with Heterodera schachtii and foot-rot and sometimes with foot-rot alone.