bluuebunny/crossref_metadata_2025 huggingface dataset:
Yield response of rice to root inoculation withAzospirillum
Authors: Rao V. Rajaramamohan , Nayak D. N. , Charyulu P. B. B. N. , Adhya T. K.
Published: March 2009

Response of rice to root inoculation withAzospirillumunder different N fertility levels was studied over three consecutive seasons under tropical conditions. The response toAzospirillumwas more pronounced at lower levels (30 and 45 kg N/ha) of fertilizer N than at a higher level (60 kg N/ha). Although the root inoculation withAzospirillumresulted in a significant increase in mean yields of both grain and straw especially at low levels of N (30 and 45 kg N/ha), the interaction between the N fertilizer and inoculation was not statistically significant.
Environmental temperature, energy metabolism and heat regulation in sheep. III. The metabolism and thermal exchanges of sheep with fleeces
Authors: Blaxter K. L. , Graham N. McC. , Wainman F. W.
Published: March 2009

1. Fifteen calorimetric experiments were made with three sheep which had fleeces varying in thickness from 2·5 to 12 cm. All sheep received a constant ration, which corresponded in amount and kind to that given to closely clipped sheep in previous experiments (Graham et al. 1958).

2. The metabolizable energy of the food increased with increasing environmental temperature by 2–3 Cal./24 hr./° C.

3. Heat production remained constant throughout the range of 15–35° C. environmental temperature. Above 35° C. an increase occurred. At 11° C. a slight rise in heat production occurred in the sheep with a 2·5 cm. fleece. These results show that sheep with fleeces, in contrast to closely clipped sheep, have very wide thermoneutral zones.

4. Heat losses by vaporization of water converged to an identical value irrespective of fleece length at 40° C. The rate of increase of vaporization with environmental temperature at lower temperatures decreased as the fleece length increased.

5. Respiratory frequencies for given total watervapour losses were the same whether or not the sheep had a fleece.
Sweating in cattle. II. Cutaneous evaporative loss measured from limited areas and its relationship with skin, rectal, and air temperatures
Authors: Taneja G. C.
Published: March 2009

1. Three female calves (Shorthorn, Zebux Australian Illawara Shorthorn, and American Brahman) of about 7–8 months old were exposed to different combinations of wet- and dry-bulb temperatures in the psychrometric chamber at the Physiology Department of the University of Queensland.

2. A capsule method has been developed for measurement of cutaneous evaporation from limited areas. This method has been described in detail.

3. Cutaneous evaporation from the shoulder area of the Zebu cross was significantly higher than that of the Shorthorn. There was, however, no difference between the two animals in their cutaneous evaporation from the belly area.

4. In the Zebu cross the cutaneous water losses from the shoulder area, on the average, increased linearly with increase in skin temperature. In the Shorthorn, there was no important increase in the cutaneous evaporation from the shoulder area, although the skin temperature increased by about 2–3/ F.

5. The Zebu cross had lower skin temperatures of the shoulder area when compared with that of the Shorthorn. These lower skin temperatures were associated with higher cutaneous evaporation.

6. Increase in rectal temperature was not accompanied by increase in cutaneous evaporation in all the three animals studied.

7. In all the three calves the cutaneous evaporation increased with increase in air temperature.
Preference thresholds for taste discrimination in goats
Authors: Bell F. R.
Published: March 2009

1. The technique for assessing rejection and acceptance thresholds for gustatory sense in goats is described.

2. Quinine dihydrochloride is rejected at a level of 125 mg./100 ml. and accepted at 12·5 mg./100 ml.

3. Sodium chloride has a rejected threshold of 5·0 g./100 ml. and an acceptance threshold of 1·25 g./100 ml.

4. Acetic acid is rejected at 5 ml/100 ml. but is accepted at 1·25 ml./100 ml.

5. Glucose does not provide data for the assessment of thresholds, since all the goats consume solutions containing the highest concentration of glucose offered, viz. 40 g./100 ml.
Potentialities of producing lean meat by restricting both energy intake and water consumption of pigs
Authors: Skipitaris C. N.
Published: March 2009

An experiment was made with growing pigs, to investigate the effect of water restriction in combination with self-fed diets of reduced energy content upon carcass quality.

The diets compared contained 5 and 30% of lucerne hay and the water treatments were ad libitum or progressively restricted amounts during the finishing period (60–90 kg live weight).

Both increasing the proportion of lucerne meal and restricting water intake reduced significantly depth of backfat and the weight of total subcutaneous fat. There was no interaction between the treatments.

The results are discussed in the light of the findings of Cunningham & Friend (1966).
Composition of body-weight change during lactation in Hereford × British Friesian cows
Authors: Trigg T. E. , Topps J. H.
Published: March 2009

Measurements were made of changes in body water, estimated by the dilution of deuterium oxide, in six Hereford x British Friesian lactating cows in their second lactation and in four of the same animals in their third lactation. The animals were subjected to a prolonged period of underfeeding followed by a period of realimentation. Milk yields were measured twice daily whilst measurement of live weight and certain blood constituents were made at 7-day intervals during the experimental periods in both years. During underfeeding milk yield differed markedly among the cows and it appeared that the cows with a higher milk potential maintained a higher yield but in doing so they incurred a greater loss of body weight. On refeeding there was little or no response in milk yield. Weight losses during the second lactation consisted mainly of body fat (calculated by difference) but the four higher yielding cows lost appreciable amounts of body water and probably significant amounts of body protein. In the third lactation all four cows lost less body fat but more body water and probably body protein than they did in the second lactation. On refeeding all animals in both years except the two lowest yielders in the second lactation gained substantial amounts of body water and probably protein but relatively little or no body fat. Significant negative and positive correlations were obtained between plasma glucose and loss of body water and between plasma free fatty acids and loss of body fat respectively.
Efficiency of nitric phosphates and Mussoorie rock phosphate in three cycles of clusterbean–wheat and groundnut–wheat rotations
Authors: Hundal H. S. , Arora B. R. , Sekhon G. S.
Published: March 2009

Nitric phosphates containing 80, 50 and 30% water-soluble phosphorus, and Mussoorie rock phosphate, alone or with Amjhore pyrites, farmyard manure or straw, were compared relative to concentrated superphosphate for each of three cycles of a clusterbean–wheat and a groundnut–wheat rotation. Both the field experiments were made on alkaline P-deficient Samana sands. All phosphatic fertilizers were applied to each crop at the rate of 10, 20 and 30 kg P/ha. Dry forage of clusterbean, groundnut pods and grain yield of wheat were measured. The model of concurrent straight line response was employed to calculate availability coefficient ratios which express the relative effectiveness of the different phosphatic fertilizers.

Nitric phosphate containing 80 % water-soluble phosphorus and concentrated superphosphate were almost equal in their effectiveness in both 3-year rotational studies of clusterbean–wheat and groundnut–wheat. The relative efficiency of the nitric phosphates increased with the amount of water-soluble phosphorus they contained. Mussoorie rock phosphate was the least effective source of fertilizer phosphorus, although its efficiency is considerably higher for the legume clusterbean and for groundnut than for the cereal wheat. The efficiency of Mussoorie rock phosphate increased when it was mixed with the soil together with Amjhore pyrites, farmyard manure and straw respectively. These materials were more effective for clusterbean and groundnut than for wheat.
Retention times in the rumen of roughages and a protein supplement
Authors: Sriskandarajah N. , Kellaway R. C. , Leibholz Jane
Published: March 2009

The extent to which proteins fed to ruminants are degraded in the rumen is determined by their rate of degradation and retention time in the rumen. It is known that retention times in the rumen are much longer for poor quality than for good quality roughages. Thus, it is possible that protein supplements may be more extensively degraded when fed with poor than when fed with good quality roughages. The present experiment was designed to determine the relationship between retention times of roughages and a protein supplement fed with them.
The effects of different suckling frequencies on the quantity of milk consumed by young lambs
Authors: Munro Joan , Inkson R. H. E.
Published: March 2009

An experiment was carried out to compare the amount of milk obtained by lambs suckling at 1-hourly intervals with that obtained by lambs suckling at 4-hourly intervals during a 24 hr. period. Statistical analyses of the figures showed that the milk consumption of lambs suckling at 4-hourly intervals was not greater than that of lambs suckling at 1-hourly intervals.
A study of subclinical worm infestation in sheep: part III. The effect on wool production
Authors: Spedding C. R. W. , Brown T. H.
Published: March 2009

1. The results of five experiments, comparing the wool production of worm free and infected sheep, are described.

2. Worm-free sheep produced (a) 12·0–38·8% higher total fleece weights and (b) 17·2–43·2% more clean, dry wool per unit area than infected sheep. None of the infestations was higher than occurs naturally in the field, but the greatest effects were associated with a low level of nutrition.

3. It is suggested that the precise effect of worm infestation on wool production will depend upon the age of the host when first infected, the size of the infestation and the rate of wool growth at the time when the infestation is at maximum.
Persistence and growth of Lotononis bainesii–Digitaria decumbens pastures: 1. Sheep stocking rate
Authors: Pott A. , Humphreys L. R.
Published: March 2009

Sheep were grazed for 2 years at stocking rates of 7, 14, 21 and 28/ha on a pasture comprising Lotononis bainesii and Digitaria decumbens cv. Pangola at Mt Cotton, south–east Queensland. There were six replicates of each treatment grazed in rotation with 3 days' grazing followed by 15 days' rest.

The initial dominance of lotononis was lost after 6 months of grazing and lotononis failed to persist satisfactorily at any stocking rate. Demographic studies showed that lotononis behaved as a short-lived plant, predominantly annual, with some vegetative perennation as stolon-rooted units under heavy grazing. Soil seed reserves varied from 5800 to 400 m2 at the lightest and heaviest stocking rates respectively. Lotononis failed to regenerate under Pangola shading or inopportune high grazing pressure. Soil bulk density (0–7 cm) increased from 1·2 to 1·4 g/cm3 according to stocking rate.
An analysis of cattle live-weight changes on tropical grass pasture during the dry and early wet seasons in northern australia: 1. The nature of weight changes
Authors: McLean R. W. , McCown R. L. , Little D. A. , Winter W. H. , Dance R. A.
Published: March 2009

Studies were conducted to elucidate the nature and cause of the drastic losses of live weight of cattle grazing buffel grass pastures after first rains at the end of the dry season in northern Australia. This paper examines trends in weight and body composition during the dry and early wet seasons; it shows that although most of the loss in fasted live weight occurred just after first rain, most of the loss of body solids, mainly fat, had already occurred by this time. Losses of body solids in the dry season were not fully reflected in live-weight losses because of increases in total body water and in gut ‘fill’. The greatly accelerated weight loss in the period following first rain appears to have been due mainly to a large reduction in gut contents. Empty-body weight actually increased during this period owing to increases in tissue water. Continuation of this trend in tissue water into the early wet season resulted in the rate of live-weight gain greatly exceeding that of body solids.
Partition of circulating triglycerides between formation of milk fat and other metabolic pathways in sheep
Authors: Glascock R. F. , Smith R. W. , Walsh Ann
Published: March 2009

An emulsion of [3H]triglycerides was used to investigate how circulating triglycerides are partitioned between milk fat, body fat and use as an energy source in lactating sheep. Immediately after intravenous injection of the emulsion the radioactivity in the blood was predominantly associated with the triglycerides of the fraction that contained chylomicrons and very low density lipoproteins. The radioactive triglyceride was used both as a precursor of milk fat and as a source of energy. The proportions utilized for these two purposes were determined experimentally and the amount retained in the carcass lipids was found by difference. In separate control experiments with nonlactating sheep the total radioactivity in the body lipids was determined by carcass analysis. This total together with that accounted for by oxidation amounted to 98% of the total radioactivity injected. These results established that the emulsion was a reliable model for the purpose intended.

The proportion of the labelled triglyceride that appeared in milk fat declined from 45% at 17 days after lambing to 8–10% at 73 days after lambing. The proportion that was oxidized was also lower in late lactation so that retention in carcass lipids was substantially increased at that time.
Influence of dietary lysine content on wool follicle function in pre-ruminant lambs
Authors: Chapman R. E. , Colebrook W. F. , Black J. L.
Published: March 2009

Wool follicles and fibres of pre-ruminant lambs abomasally fed isoenergetic diets with daily amounts of lysine ranging from 0·12 to 1·94 g/(kg live weight)0·75were examined by light and electron microscopy. In lambs which receivedca.0·9 g lysine/kg0·76daily, the follicles appeared normal, whereas in those which received less than 0·9 g lysine/kg0·75daily several follicle abnormalities developed and the percentages of follicles affected increased as the amount of lysine was decreased. These abnormalities included the formation of autophagic vacuoles (or apoptotic bodies) in follicle bulb cells, and retarded and incomplete keratinization of the wool fibres, which led to the kinking of fibres at the mid-dermal level and gross distortion and partial degradation of fibres in the distal parts of follicles with thickened outer root sheaths. Following the introduction of a low-lysine diet, autophagic vacuoles developed in most follicle bulbs within 24 h. Impaired keratinization and kinking of fibres were evident in increasing proportions of follicles after 2 days, and gross distortion of fibres after 3–4 days. When the lambs were returned to a diet with adequate lysine recovery of normal follicle structure followed a similar time pattern, except that gross distortion of fibres persisted in the distal parts of some follicles for longer than 1 week. In some lambs given more than 0·9 g lysine/kg0·75daily a small percentage of follicles had short keratogenous zones. Clumping of fibres, which occurred in the proximal parts of a small number of follicles, was unrelated to the amount of lysine in the diet.
Effects of sowing date on plant establishment and bolting and the influence of these factors on yields of sugar beet
Authors: Jaggard K. W. , Wickens R. , Webb D. J. , Scott R. K.
Published: March 2009

This study examined the effect of early sowing of sugar beet on plant establishment, bolting and yield and whether or not the standard of establishment and degree of bolting determined the most appropriate harvesting sequence. At Arthur Rickwood Experimental Husbandry Farm four experiments were made between 1974 and 1978 testing four sowing dates of four varieties each harvested on three occasions during the autumn. At Broom's Barn three dates of sowing of two varieties were tested in three experiments between 1976 and 1978. Sowing dates throughout the experiments covered a range from late February to late April. Also, at Broom's Barn in 1977 there were many bolters (plants which have a tall, flower-bearing stem) where the crop was sown on 4 March. The effects of bolter-control treatments, either cutting down the inflorescence or removing the plant, on sugar yield were compared. Sowing before mid-March often resulted in very gappy crops and many bolters; in consequence yields were seriously reduced. Late-March sowings were almost free from plant establishment problems and, where the bolting-resistant variety ‘Nomo’ was used, bolters were few; yields of Nomo were greater than where sown in early April. Progressively more yield was lost by delaying sowing throughout April. Variation in the extent of bolting between sites, seasons and sowing-date treatments was accounted for by variation in the number of cool days (with a maximum temperature of less than 12 °C) after sowing. Yield was lost at a rate of 0·7% for every 1% of bolters over the range 5–40% bolting. During the autumn, crops at Arthur Rickwood which had more than 5% bolters and/or less than 60000 plants/ha gained 0·45 t/ha less sugar than did those with full, bolterfree plant stands. In 1977 many of the early-sown plants bolted; pulling the bolters or cutting the inflorescences improved yield, but not sufficiently to raise yields to the level produced by later-sown, bolter-free crops.
Altitudinal effects on Stylosanthes guianensis at a low latitude site: 2. Seed production
Authors: Ison R. L. , Humphreys L. R.
Published: March 2009

Seed production of five selections of Stylosanthes guianensis var. guianensis was studied in Bali, Indonesia (latitude 8° 30′ S) with a series of harvests at three sites of increasing altitude and rainfall: (1) Sesetan, 10 m, (2) Kuwum, 280 m and (3) Pekarangan, 1000 m. Seed yield of cv. Graham, CPI 34906, cv. Cook and cv. Endeavour was maximal at Sesetan with yields of 109, 39, 38 and 166 g/m2 respectively, whilst cv. Schofield, which flowered little at low altitude, produced 12 g/m2 at Pekarangan. Optimum time of harvest varied from 26 April for cv. Graham at Sesetan to 1 November for cv. Schofield at Pekarangan. Yield stability over sites was greatest in cv. Graham, in which increased number of florets per spike at high altitude partially compensated for negative altitudinal effects on spike density. Disease reduced yields of cv. Cook and cv. Endeavour at Kuwum and Pekarangan and the incidence of rainfall at advanced stages of crop development reduced spike density and seed maturation.

It is suggested that the high seed yields attained at the low altitude, low latitude Sesetan site were attained via (1) vigorous vegetative growth and a longer duration of floral induction resulting in high bud site density, (2) high bud site fertility, (3) high seed set (ca. 70–80%), (4) high seed weight and (5) little or no disease or insect damage. The greater synchrony of flowering at higher latitude sites may be less critical for high levels of seed production than the greater length of crop development available at low latitudes.
Field drainage and nitrogen leaching: some experimental results
Authors: Armstrong A. C. , Shaw K. , Wilcockson S. J.
Published: March 2009

Public concern continues to be expressed about the quality of water discharged from agricultural lands. High concentrations of nitrate nitrogen are often blamed on modern agricultural practice in general and to land drainage in particular (Royal Commission on Environmental Pollution, 1979, para. 4.38). However, undrained land also discharges water by flow within the soil and across the soil surface and it may discharge significant quantities of solutes.
Sweating in cattle. V. Sweat prints
Authors: Taneja G. C.
Published: March 2009

An American Brahman calf of about 7–8 months age was placed in a hot chamber with a temperature of 108° F. dry bulb and 92° F. wet bulb. Sweat droplets were detected by preparing sweat prints on tannic acid papers applied closely to shaved skin areas smeared with ferric chloride solutions. The distribution of sweat spots on the sweat prints is similar to that of sweat glands.
Field studies on the growth and development of winter wheat
Authors: McLaren J. S.
Published: March 2009

The effects of variety, plant density and time of N application on the yield and yield components of winter wheat were investigated in factorial experiments during 1977–8 and 1978–9, at Sutton Bonington. Armada produced substantially fewer vegetative tillers/m2but the number of ears/m2, from anthesis onwards, was similar to that of Maris Huntsman. The effects of the time of N application on tiller production and survival differed between the 2 years and may have been related to the amount of residual N in the soil. A linear relationship was found between the number of tillers/m2which died and the maximum number of tillers/m2.

Kador produced a lower grain yield than Armada or Maris Huntsman, owing to a combination of lower ratio of grain D.M. to total above-ground D.M. (harvest index) and lower total dry-matter production. Armada produced a higher grain yield than Maris Huntsman in response to earlier application of N. Grain yield was less variable when final plant densities were greater than 200/m2.

Grain yield was not particularly well related to individual yield components but showed a good linear relationship with number of grains/m2. Grain yield was also linearly related to total dry-matter production, with treatment effects on harvest index being relatively small. The results indicate that factors which influenced crop growth during grain site development were relatively more important than the factors affecting subsequent grain filling.
Effects of cattle grazing, sheep grazing, cutting and sward height on a grass-white clover sward
Authors: Briseño De La Hoz V. M. , Wilman D.
Published: March 2009

Thirteen defoliation treatments were applied to a grass-white clover sward for 2 years to study some effects on the sward of cattle grazing compared with sheep grazing compared with various cutting treatments and to study the effect of height of defoliation.

Sheep actively sought out the clover in preference to grass whereas the cattle did not. The response of the clover to sheep grazing was a large reduction in the amount of stolon, shorter internodes, petioles and leaflets, and thinner stolon closer to the ground. Reducing the height of defoliation from 8 to 4 cm above ground level also reduced the dimensions of white clover. The clover, however, appeared to recover quickly and completely from the effects both of sheep grazing and of reducing the height of defoliation when these treatments were discontinued. In plots cut for hay the clover disappeared from the sward suddenly and completely in dry conditions following the 2nd-year hay cut. The effect of cattle grazing on white clover was similar to the effect of comparable cutting treatments. Cattle grazing, however, reduced the number of tillers of grass andincreased the proportion of bare ground, compared with cutting or sheep grazing. Grazing rather than cutting tended to encourage perennial ryegrass and to discourageHolcus. Cutting for hay encouragedBromus mollis. Reducing the height of defoliation reduced leaf sheath and blade length and the rate of production of new blade per tiller in perennial ryegrass, but increased the numbers of tillers of grasses.
Genetic studies on peak yield in Holstein Friesian × Sahiwal cross-bred cattle
Authors: Deshpande K.S. , Bonde H. S.
Published: March 2009

Analyses of data on first peak yields of 1346 Holstein Friesian (HF) × Sahiwal crossbred cows belonging to four Indian military dairy farms were carried out. There were highly significant differences amongst different grades. The < ⅛ HF had the minimum (9·35 kg) and £ HF had the maximum (12·77 kg) peak yield during first lactation. Half-breds appeared to be most suited for peak production. Genetic grades, farms and periods of calving had highly significant, and season of calving had significant, influences on peak yield in cross-bred cows. Heritability of peak yield was 0·405±+ 0·023. Peak yield had highly significant and positive genetic and phenotypic correlations with total lactation yield, 300-day milk yield, milk yield per day of first calving intervaland milk yield per day of age at second calving. Interval, in days, between the dates of first and second calvings was considered the first calving interval. Age, in days, at the time of second calving was considered age at second calving. The high heritabilities and desirable correlations indicate the possibility of satisfactory correlated response in thesetraits, if selection is based on peak yield.
The effect of varying plant population density on the seed yield of Navy beans (Phaseolus vulgaris)in south-east Enland
Authors: Scarisbrick D. H. , Wilkes J. M. , Kempson R.
Published: March 2009

Navy beans were precision drilled in 1973–5 at a range of plant population densities. Within each growing season the density treatments did not influence seed yield, but mean yields differed significantly between years. The results suggest that cultivars similar to Purley King can only be regarded as a reliable break crop in a season such as 1973 which was slightly warmer and drier in mid-summer than average. Although the rate of drying increased with increasing plant density in two of the growing seasons, no practical advantages are proposed.
Oil content of cotton seed in Northern Nigeria: 1. Assessment of nuclear magnetic resonance for the determination of the oil percentage of cotton seed
Authors: Smithson J. B. , Gridley H. E.
Published: March 2009

The oil content of a number of introduced and local varieties was determined using three nuclear magnetic resonance oil analysers at different centres and compared with results from conventional solvent extraction. Differences were evident between the three centres and between the techniques but in both cases the rankings were similar.
The development of winter wheat in the field. 1. Relation between apical development and plant morphology within and between seasons
Authors: Baker C. K. , Gallagher J. N.
Published: March 2009

Main-stem apical development and its inter-relations with other aspects of plant morphology were studied in seven field crops of winter wheat (Triticum aestivumL., cv. Maris Huntsman).

Apical primordia were produced slowly in autumn and winter, then faster in spring as the weather became warmer. Spikelets were initiated about three times as fast as leaves. Leaf initiation ended at around the time that tiller bud initiation stopped. Apical dome length and diameter both increased during leaf initiation, reached a maximum at double ridges and then decreased. Double ridges appeared when very nearly 50% (range 49–52%) of the final number of spikelets was present. Spikelet initiation ended a few days after the first florets were initiated and when stem extension began, but usually before the stem apex rose above the soil. Floret initiation finished at about the time that the flag leaf appeared. Throughout tillering there was a strong association between tiller emergence and leaf appearance.

There were considerable differences between seasons in the timing of developmental events on the apices of main stems, but a difference in sowing date of 5 months was reduced to little more than 1 month in the timing of anthesis and the maximum numbers of organs varied only slightly with sowing date.
The efficiency of incomplete block designs in National List and Recommended List cereal variety trials
Authors: Patterson H. D. , Hunter E. A.
Published: March 2009

Use of generalized lattice designs instead of complete block designs in 244 cereal variety trials grown in the U.K. since 1975 has resulted in an average reduction of 30% in variances of varietal yield differences. The lattice designs were most effective when the number of varieties was more than 50 but worthwhile reductions in variance, averaging about 24%, were obtained in trials with fewer than 20 varieties. The data also provide guidance on the choice of block size and the potential for improvement by neighbour methods.
Grain and fodder legumes as preceding crops affecting the yield and N economy of rice
Authors: De R. , Rao Y. Yogeswara , Ali W.
Published: March 2009

Experiments made for 2 years on a sandy-loam soil showed that previous grain crops of mung bean (Vigna radiata), cow pea (V. unguiculata) and black gram (V. mungo) increased the grain and straw yield of a subsequent crop of rice relative to previous fodder crops of maize or guar bean (Cyamopsis tetragonoloba) or a grain crop of Phaseolus bean (Phaseohcs vulgaris). The benefits from preceding crops of mung bean, cow pea or black gram were equivalent to 36–67 kg N/ha of chemical fertilizer applied to the rice crop following a cereal. The legumes improved yield-contributing characters such as number of productive tillers/m2, panicle length and number of grains/panicle. The yield increase from the preceding legumes was noted even when the rice crop was given increasing rates of fertilizer up to 90 kg N/ha.
A barley breeding programme based on an ideotype
Authors: Donald C M.
Published: March 2009

An attempt has been made to produce barley lines in accordance with an ideotype designed in 1968. Current lines are early maturing, uniculm, six-row barleys, of medium height, high harvest index, and moderate resistance to lodging. However, they have lax leaves of medium length, in contrast to the short, erect leaves of the ideotype. When sown in narrow rows at a rate three times that of tillered lines, they have given grain yields greater than the two- and six-row tillered controls, especially in favourable seasons, but less so in dry years. The quality of the grain has not been examined. In the absence of plasticity in number of tillers, uniculm lines show increased plasticity in number of grains per ear and weight per grain. It is possible that the uniculm habit, apart from effects on morphology and maturity, may permit more exacting selection of high-yielding plants than is possible among plants each comprising many mutually competing culms.
The effects of implanting prepuberal dairy heifers with anabolic steroids on live-weight gain, blood and urine composition and milk yield
Authors: Little W. , Kay R. M. , Harwood D. J. , Heitzman R. J.
Published: March 2009

Twenty-seven British Friesian heifer calves were housed as a group but fed individually barley-lucerne pellets according to a scale related to body weight. At 16 weeks and again at 31 weeks of age nine calves were implanted subcutaneously at the base of the ear with 300 mg trenbolone acetate (group T), nine calves were similarly implanted with 140 mg trenbolone acetate and 20 mg oestradiol-17/? (group TE) and the remaining nine calves were sham implanted (group C).

As a result of increased feed conversion ratios, body-weight gains were significantly greater in group T (0–80 kg/day) and group TE (0–87 kg/day) than in group C (0–72 kg/ day) during the 15 weeks following the second implant, but there was no significant difference between groups following the first implant.

Following both implants in groups T and TE the mean concentrations of urea and albumin in serum decreased, and that of globulin increased. The mean urea: creatinine ratio in the urine of animals in groups T and TE relative to that in group C also decreased.

The heifers were served by an Aberdeen Angus bull at the first and, when they occurred, subsequent oestruses. Following calving the mean milk yields in the first lactation in group T (641 kg in 96 days) and group TE (1993 in 212 days) was considerably lower than in group C (3636 kg in 293 days). The udder size in both groups of animals treated with the anabolic steroids was markedly reduced. It is concluded that despite an improvement in feed conversion ratios and body-weight gains, trenbolone acetate should not be administered to prepuberal heifers which will be retained for breeding and milk production.
Effect of ammonium on the regulation of sodium transport in Helianthus annuus
Authors: Ragab S. M.
Published: March 2009

The electrical potential difference between exuding sap of detopped sunflower plants and rooting media containing different NH4 ion concentrations was measured, together with the Na and K concentrations in root tissue and their fluxes in the xylem exudate. It was found that adding NH4 ions to the medium made the electrical potential difference less negative with respect to the external solution and decreased the water conductivity of roots. Moreover, fewer K and Na ions were transported to the xylem sap and the K concentration in root tissue after 3 h had decreased whereas that of Na had increased. These results suggest that the sunflower root acts as an efficient accumulator for Na rather than simply as a barrier to Na transport. It is suggested that NH4 ions caused a decrease in charge separation across one of the barriers where Na is actively transported so that adding NH4 ions to the medium increased Na accumulation in root cells. This barrier may have been at the symplast.
Unrestricted whey for fattening pigs
Authors: Braude R. , Clarke P. M. , Mitchell K. G. , Cray A. S. , Franke A. , Sedgwick P. H.
Published: March 2009

1. Results are reported from two experiments in a series to determine the optimal amount of meal to be fed in conjunction with unrestricted whey for fattening pigs.

2. In both experiments, one carried out during the summer and the other during the winter season, the same four treatments were given. The control pigs received meal ad. lib up to a maximum of 6½ lb./ head daily. Pigs on the other three treatments received whey ad lib., and either 3 lb., or 3 lb. reduced at two different stages to 2 lb. of meal per head daily. There were ten pens of nine pigs on each treatment, involving a total of 360 pigs. Comprehensive carcass measurements were made on all pigs.

3. The data obtained showed that satisfactory results could be obtained by feeding a daily allowance of 3 lb./pig of a proprietary sow and weaner meal throughout the fattening period, in conjunction with unrestricted whey. Where the utilization of as much whey and as little meal as possible was required, it was shown that a reduction from 3 to 2 lb. meal/pig/day by the 13th week of life could be made without adverse effects, apart from an increase of approximately 12 days in the time taken to reach bacon weights.

4. Carcass grading results of all whey-fed pigs were reasonably satisfactory, but both the carcass grading and general performance of the control animals was not good. Possible reasons for this were discussed.

5. Data concerning the pattern of food consumption over 14-day periods throughout the experiments were presented. Pigs given 3 lb. of meal/day throughout, or 3 lb. reduced to 2 lb./day, consumed up to approximately 3¼–3½ or 3¾–4 gal. of whey/day respectively.
Carcass length measurement in bacon pigs
Authors: Braude B. , Mitchell K. G. , Harrington G.
Published: March 2009

1. Two experiments involving length measurements of ninety-six bacon-pig carcasses showed that chopping out the backbones, chilling and laying the carcasses down on a table, each resulted in a decrease in average length. There was variation from carcass to carcass in the magnitude of these decreases which, in the case of the chopping out the backbone and laying down stages, was related to the fatness of the carcass, greater decreases being found in the longer, leaner carcasses than in the shorter, fatter sides.

2. Estimates of the precision of measuring showed that length from the junction of the first rib and the sternum to the symphysis pubis taken on hanging carcasses was less susceptible to errors than the same measurement taken on the lying carcass, and that both these measurements were more accurate than that from the atlas bone to the symphysis pubis taken on carcasses either hanging or lying.
Nitrogen and phosphorus fertilizer sources and placement methods in maize (Zea mays L.) using labelled fertilizers
Authors: Papanicolaou E. P. , Skarlou V. D. , Nobeli C. , Katranis N. S.
Published: March 2009

The influence of various nitrogen and phosphorus sources, applied at the preseeding stage with two placement methods, on maize yield and fertilizer utilization, was studied in two field experiments and a pot experiment with a calcareous, heavy to medium heavy textured recent alluvial soil.

Phosphorus alone had no effect on crop yield. Nitrogen alone or nitrogen (various forms) and phosphorus had a clear positive effect on crop yield. As to the various sources the observed differences in the crop yield of the field experiments were not significant, while in the pot experiment ammonium sulphate gave the highest yields.

The data on the phosphate concentrations in the tops derived from phosphate fertilizer (Pf) indicate that the presence of nitrogen increased the utilization of phosphorus fertilizer. From the tested placement methods the incorporation method appears clearly superior in the pot experiment with a similar trend in the field experiment for all sources except ammonium phosphate-sulphate.

The utilization coefficients of the nitrogen fertilizer sources suggest that ammonium and urea were better utilized than nitrates, that the higher nitrogen utilization reflected higher yields and that phosphorus fertilizer exerted a beneficial effect on nitrogen fertilizer utilization. Finally they suggest that the addition of 120 kg N/ha enhanced the amount of soil nitrogen taken up in the maize grain by 53%.
Lodging studies inLolium perennegrown for seed: 3. Chemical control of lodging
Authors: Wright D. , Hebblethwaith P. D.
Published: March 2009

Three field experiments at the University of Nottingham, in 1976, 1977 and 1978, examined whether a growth retardant chemical, ancymidol, could be used to restrict stem extension, delay the onset of lodging and thereby increase the seed yield of S. 24 perennial ryegrass. Applications of ancymidol increased seed yield by up to 60% by increasing number of seeds per unit area, although this was associated with a delay in the onset of lodging in 1977 and 1978 only. Application of ancymidol increased the percentage of the total above-ground crop dry matter harvested as seed, but it was not possible to relate this to the growth of the crop between anthesis and harvest.
The effects of aldicarb, triazophos and benomyl plus zineb on the incidence of pests and pathogens and on the yields and nitrogen uptakes of leafless peas (Pisum sativum L.)
Authors: McEwen J. , Cockbain A. J. , Fletcher K. E. , Salt G. A. , Wall C. , Whitehead A. G. , Yeoman D. P.
Published: March 2009

Experiments testing the effects on leafless peas of aldicarb, triazophos and a mixture of benomyl with zineb, were made on clay-with-flints soil at Rothamsted and on sandy loam at Woburn in 1977 and 1978.

The crop was shown to be susceptible to a wide range of pests and pathogens including the pea and bean weevil Sitona lineatus, the migratory nematode genera Pratylenchus, Tylenchorhynchus and Tylenchus, the pea moth Cydia nigricana, the aphids Acyrihosiphon pisum and Macrosiphum euphorbiae, the bean leaf roll and pea enation mosaic viruses and the powdery mildew fungus Erysiphe polygoni.

The mean yield of the four experiments when none of the treatments was applied was 3·6 t grain/ha, increased to 4·3 t/ha when all were applied. Aldicarb had the largest effect and increased mean yield at Rothamsted by 0·3 t/ha, attributed mainly to control of S. lineatus, and by 0·8 t/ha at Woburn attributed to control of S. lineatus and perhaps also to migratory nematodes, particularly Tylenchorhynchus. Triazophos and benomyl plus zineb did not individually increase yield but at Woburn when both aldicarb and triazophos were applied benomyl plus zineb increased mean yield by 0·7 t/ha.

All crops lodged severely, irrespective of treatment but perhaps because of experimental conditions. We suggest that susceptibility to lodging under field-scale conditions requires further study.
The effect of body-weight changes during pregnancy and lactation on the performance of three breeds of sheep
Authors: Mavrogenis A. P. , Hancock J. , Louca A.
Published: March 2009

Three husbandry systems were used to promote differential live-weight gains in 603 Cyprus Fat-tailed, Chios and Awassi ewes. Ewes on the high level of feeding had heavier litters than those on the medium and low levels. Litter size was not affected by level of feeding during pregnancy. Milk production was highest (P < 0·01) for ewes on the high level. The milk production of Chios and Awassi ewes was similar on the high and low feeding levels, but Awassi ewes outyielded both other breeds on the medium level. Chios ewes had larger and heavier litters (P < 0·01) than both other breeds. The correlations between live weights during lactation and milk yield were low and negative indicating a tendency for body loss at high yields.
Patterns of yield production in two semi-dwarf and two conventional height European spring wheats
Authors: Angus W. J. , Sage G. C. M.
Published: March 2009

Two semi-dwarf and two conventional height European spring wheat varieties were grown at different sowing dates and sowing rates in two dry years. Yield component analysis showed the varieties to fall into three groups. The conventional height varieties were dependent for grain yield on either a high number of ears or a large number of spikelets per ear whereas the semi-dwarfs were dependent on high spikelet fertility.

The semi-dwarfs were consistently higher yielding over a range of environmental conditions than the conventional height varieties. Maintenance of high yield was associated with high spikelet fertility and 1000-grain weight, characters determined late in development. It is suggested that the change to the semi-dwarf plant type has resulted in high yields with greater consistency over a range of environmental conditions particularly when dry.
Methods of milk production: some results of a survey in four areas of England and wales
Authors: Leech F. B. , Egdell J. W. , Heskin P. , Thomas S. B.
Published: March 2009

1. Methods, buildings and equipment used for milk production in Caernarvonshire, Hertfordshire, Pembrokeshire and Wiltshire have been ascertained by a random sample survey carried out in 1948–9.

2. The results showed marked differences between counties in practically every respect which are summarized in thirty-two tables.

3. The value of this survey and some points in its planning and execution are critically discussed.
Investigations into the chemical composition and nutritive value of certain forage plants at medium altitudes in the tropics I. Seasonal variation in the chemical composition of the grassesBothriochloa insculpta, Chloris gayanaandBrachiaria dictyoneura, under rotational light grazing, with a note on the persistence of the grasses
Authors: Todd J. R.
Published: March 2009

Seasonal variations in the contents of organic and inorganic constituents of three East African grasses,Bothriochloa insculpta, Chloris gayanaandBrachiaria dictyoneuraare reported.

Protein content is closely associated with rainfall and the stage of growth of the grasses. Protein content of from 15 to 20% is maintained for a short time only, at the beginning of the rainy season. During the dry season the values fall to 4–5%.

Even in the vegetative phase the fibre contents are relatively high, 23% being the lowest figure recorded.

A common feature of the grasses is a high content of silica, which may amount to more than 10% of the dry matter.

The phosphorus content of the grasses is low, ranging from 0·65% P2O5in young grass during the rainy season to 0·13% during the dry season.
The effect of floor type and the choline content of the diet upon the incidence of perosis in chickens
Authors: Cumming R. B. , Tribe D. E.
Published: March 2009

1. A series of experiments, involving the use of three hundred and forty Rhode Island Red x Light Sussex day-old cockerels, was carried out to determine (a) the influence of floor type on the incidence of perosis, and (b) a method of lowering the high incidence of perosis which may occur when chicks are fed the experimental diet no. 124 originally described by Damet al.(1951).

2. It was found that the incidence of perosis was about 60% higher in groups of chicks raised on wiremesh floors than in groups of chicks similarly raised on wooden floors.

3. Neither the area of the floor space nor the level of manganese in the diet influenced the incidence of perosis.

4. When the calculated choline content of the diet was 500 mg./kg. the incidence of perosis was 60% but when it was raised to above 800 mg./kg. the incidence fell to about 15%. This could not be reduced further by further increasing the choline content.

5. Since the rate of body-weight gain increased as the choline content of the diet was raised to 1400 mg./kg. it is suggested that diet no. 124 may be improved from both the points of view of perosis prevention and of growth rate if the choline content is raised to 1500 mg./kg. of diet.
Calculation of confidence limits of monthly rainfall
Authors: Manning H. L.
Published: March 2009

Glover & Robinson (1953) have recently criticized the use of a transformation in calculating confidence limits of monthly rainfall, and have suggested that the technique is complicated and even misleading. They contend that the use of unadjusted monthly data leads to no serious discrepancies. If this were in fact so, there is no doubt that much time and effort could be saved. It is therefore desirable to compare the two techniques, and to set out against the recorded data the predictions obtained from them.
Investigations into the chemical composition and nutritive value of certain forage plants at medium altitudes in the tropics III. The digestibility and nutritive value of grass and legume hays and ‘standing hays’
Authors: Todd J. R.
Published: March 2009

1. The results are presented of two series of digestibility trials. The first series consists of six grass hays, cut at different stages of growth, and two legume hays cut at the flowering stage. The second series consists of trials using seven species of grasses at the ‘standing hay’ stage.

2. Good-quality grass hays are obtained from grasses at the flowering stage. More mature grasses yield poor- or very poor-quality hays of low-protein content.

3. The legume hays were of good quality, being particularly high in digestible protein.

4. The grasses at the ‘standing hay’ stage are generally of poor feeding value, Brachiaria brizantha, a drought-resistant species, being the best of the seven studied.

5. From these results a tentative conclusion is drawn that, during the dry season, the extensive grazing areas of East Africa are capable of providing, at the most, for the maintenance requirements of ruminants.