bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of ruthenium and chromium by X-ray fluorescence spectrometry and the use of inert ruthenium (II) phenanthroline as a solid phase marker in sheep digestion studies
Authors: Evans C. C. , Macrae J. C. , Wilson S.
Published: March 2009

The quantitative estimation of ruthenium and chromium in faeces and digesta from sheep by X-ray fluorescence spectrometry is described. Estimates of calibration parameters, established by regression analysis, were applicable to a range of matrices. Lower limits of detection of 2·4 mg Ru/kg (solid), 1·8 mg Ru/1 (liquid), 1·6 mg Cr/kg (solid) and 1·1 mg Cr/1 (liquid) and precisions, expressed as coefficients of variation, of 5·4% at 17·7 mg Ru/kg (solid), 5·1% at 182·7 mg Cr/kg (solid) and 1·1% at 152 mg Cr/1 (liquid) were acceptable for the routine analysis of Ru and Cr.

The use of inert ruthenium phenanthroline (Ru-P) and inert chromium ethylenediamine tetra-acetic acid (Cr-EDTA) as solid:liquid dual phase markers in digestive physiological studies was evaluated. The specificity of Ru-P for the particulate phase of digesta, established by both in vitro and in vivo experiments, was found to be 92–98%, and in vivo recovery of intraruminally administered Ru-P in faeces was 97–101%. In vitro incubation of rumen liquor showed that concentrations of Ru-P up to 10−4 M had little effect on volatile fatty acid production rates but at 10−3 M there was virtually complete inhibition of acetate and propionate production.

Advantages of using inert Ru-P as a solid phase marker are discussed.
Dry-matter production, yield, photosynthesis, chlorophyll content and specific leaf weight of cotton in relation to leaf shape and colour
Authors: Karami E. , Weaver J. B.
Published: March 2009

Analysis of seasonal growth and fruit production of American Upland Cotton (Gossypium hirsutum L.) with different combinations of leaf shapes and colours was made in 1970. Plants with the ‘okra’ leaf shape (LOLO) had a higher photosynthetic rate, number of green bolls, number of ‘squares’ (flowering buds) and flowers, dry weight of fruiting parts, fruiting index, harvest index (ratio of seed cotton to total biological yield), yield and lint percentage than plants with normal leaves.

There were no significant differences in specific leaf weight (SLW) due to leaf shape. There was no significant correlation between SLW and photosynthetic rates among biotypes. There were no significant differences in different characteristics measured regarding leaf colours.
Pre-lambing supplementation of gadic ewes in western Afghanistan
Authors: McArthur I. D.
Published: March 2009

A survey of sheep production was undertaken in rangeland areas of western Afghanistan to provide basic information of ewe body-weight changes throughout the year and on production variables, including mortality and lambing performance. Ewes lost up to 31% of body weight between December and March and mortality over the same period was 7%. On the basis of the results of this survey, an experiment was made to test the effect on lambing performance of pre-lambing supplementation of range-based ewes.

Supplementation reduced weight losses in ewes, but the feeding treatments did not produce significant results in terms of lamb birth weights or survival to 10 days. However, there were indications that selective feeding of weak ewes can produce economic benefits, given that the costs of supervising such animals are minimal and the price of grain supplements is low relative to the price of meat.
Field experiments on phosphate fertilizers: A joint investigation
Authors: Cooke G. W.
Published: March 2009

The results of over 400 field experiments testing different kinds of phosphate fertilizers are summarized and are discussed with special reference to the reactions of the soils used. The classifications were:‘very acid’ soils—pH below 5·5, ‘acid soils’— pH 5·6 to 6·5, neutral soils—pH over 6·5. All comparisons are made in terms of fertilizers supplying the same amounts of total phosphorus.

In war-time experiments Gafsa and Morocco rock phosphates were about two-thirds as efficient as superphosphate for swedes and turnips grown on very acid soils. In 1951–3 experiments on very acid and acid soils Gafsa phosphate was practically equivalent to superphosphate for swedes, but for potatoes it was as effective as only one-third as much phosphorus supplied as superphosphate; on neutral soils Gafsa phosphate was useless. For establishing grassland on acid soils Gafsa and Morocco phosphate were equivalent to about onethird as much phosphorus supplied as high-soluble basic slag. Rock phosphates were somewhat more effective for promoting growth of established grassland but they remained inferior to high-soluble basic slags and to superphosphate. Curacao rock phosphate was roughly equivalent to Gafsa phosphate for swedes and grass. Florida pebble phosphate was much less effective and was judged unsuitable for direct application. Mixtures of rock phosphate with superphosphate were not more efficient than equivalent amounts of the separate components used correctly.

Silicophosphate was practically as effective as superphosphate for swedes grown on very acid and acid soils; it was less efficient on neutral soils. For potatoes silicophosphate was nearly as effective as superphosphate on very acid soils; it was much less efficient on acid and neutral soils. Silicophosphate was roughly equivalent to high-soluble basic slag for grassland.

Mixtures of superphosphate with lime, serpentine, and low-grade basic slag were prepared, most of the water-soluble phosphorus being converted to insoluble forms. In experiments on swedes and potatoes these basic superphosphates were not superior to untreated superphosphate. For establishing grassland on very acid soils, the mixtures were slightly superior to ordinary superphosphate.

Dicalcium phosphate was practically equivalent to superphosphate for swedes on all groups of soils. For potatoes dicalcium phosphate was more efficient than superphosphate on very acid soils, on less acid and neutral soils it was inferior to superphosphate.
Incomplete determination of a measure of quality in a series of experiments
Authors: Finney D. J. , Nissen Ø.
Published: March 2009

Often the ultimate measure of performance in a field experiment is the product of a gross weight and a factor relating to quality, as when yield of dry matter is determined from gross yield and percentage dry matter. Since the factor is usually much less variable than the gross yield, yet relatively troublesome and expensive to determine, the practice of making independent estimates of it in every experiment involves diversion of an appreciable part of the total expenditure to a measurement whose inaccuracy will affect only slightly the final experimental error.

Proposals are made for determining the quality factor on only a fraction of all the experiments of one series and applying the averages to the gross yields of others in the same series; formulae and tables relating to the most economic ratio of incompletely to completely recorded experiments are presented.
Results from an experiment comparing aqueous ammonia with ‘Nitro-Chalk’ for grazed grass
Authors: Widdowson F. V. , Penny A. , Flint R. C.
Published: March 2009

Aqueous ammonia supplying 125, 250, 375 or 500 kg N/ha was injected in spring (in bands 10–13 cm deep and 30 cm apart) into old permanent pasture stocked with cattle. Yields from it were compared with those from ‘Nitro-Chalk’ supplying the same total quantities of N, but broadcast in six equal amounts during the growing season. The tests were made first in 1969 and repeated on the same plots in 1970 and in 1971.

Yields of herbage were measured by placing cages (0·9144 m square) on different parts of each plot during six grazing periods of an 8-month growing season (1 March to 30 October). The cages protected this grass from cattle, otherwise grazing unrestrictedly.

Aqueous ammonia produced slightly more dry matter during the first three periods (1 March to 30 June) and ‘Nitro-Chalk’ slightly more during the last three (1 July to 30 October). Total yields from the two sorts of N were similar.

Percentage N in dry herbage was larger with aqueous ammonia than with ‘Nitro- Chalk’ during the first three periods, the same with both fertilizers during the fourth, but larger with ‘Nitro-Chalk’ during the fifth and sixth periods.

Without N the pasture contained 36% of wild white clover during the first three grazing periods and 28% during the last three. Giving 125 kg N/ha of either fertilizer decreased clover by more than half, and with more N the pasture contained less than 5% of clover.
Measurement of feed intake of grazing sheep: II. The estimation of faeces output using markers
Authors: Lambourne L. J.
Published: March 2009

1. One of the biggest difficulties in the measurement of the feed, intake of grazing animals by the indirect method using indigestible ‘markers” is to determine the optimum frequency for dosing and for taking faeces samples in order to achieve greatest accuracy while yet retaining realistic free-grazing conditions of husbandry.

2. Results of earlier studies of the rate of excretion of individual doses of marker by grazing sheep are used to illustrate the probable outcome of various schedules of dosing.

3. It appears that if marker doses were administered and faeces samples were taken twice daily at alternate intervals of 9 and 15 hr. approximately, the mean marker concentration of these samples would yield an essentially unbiased estimate of the general level of marker in the faeces. Since there is no satisfactory evidence that animals fail to excrete all the marker administered, it should be possible then to derive estimates of mean faeces output with an error probably of the order of + 10%.

4. This technique was tested in two stall-feeding trials and and one free-grazing trial with a total of seventeen sheep.

5. The unweighted mean of the estimates of faeces dry-matter output for the seventeen individual sheep periods was about 100 ± 8%.

6. Alternative methods of bulking the faeces samples so as to yield estimates of group mean faeces output are considered, but the possibility of introducing a serious bias by the bulking process is pointed out.
A survey of the potassium concentration in the red blood cells of British breeds of sheep
Authors: Evans John V. , Mounib M. S.
Published: March 2009

The concentrations of potassium in the whole blood of representative samples of sixteen British breeds of sheep have been studied.

The proportion of sheep with a high level of potassium in the whole blood (high potassium or HK type) was found to differ significantly between breeds. It ranged from 0% in the English Leicester to 73% in the Rough Fell.

There were significant differences between breeds in the mean concentration of potassium in the whole blood of both the LK and HK sheep.
Development of a standard bioassay technique for the adults of Bemisia tabaci Gennadius (Homoptera, Aleyrodidae)
Authors: El-Helaly M. S. , El-Gayar F. H. , El-Shazli A. Y.
Published: March 2009

A standardized impregnated filter-paper bioassay technique was specially developed for screening insecticides against adults of the whitefly Bemisia tabaci Genn. (Homoptera, Aleyrodidae). It was found that the most suitable exposure period, after which mortality counts should be made, was 11·7 ± 2·1 h. Two different techniques for applying the insecticide solutions to the filter paper disks were tested and verified.
Results from two sets of experiments with spring barley, the first comparing injected with broadcast nitrogen granules, the second comparing injected and combine-drilled NPK solutions with broadcast NPK granules
Authors: Widdowson F. V. , Penny A.
Published: March 2009

Six experiments from 1969–71 compared yields of, percentages of N in, and removals of N by barley given 63 or 126 kg N/ha either as urea or as ‘Nitro-Chalk’ which were either broadcast or injected into the seed bed. Both fertilizers were equally effective and each gave a slightly larger yield when injected.

Eleven more experiments compared yields of, percentages of N in, and removals of N by barley given either NPK solution fertilizers or NPK granules supplying 63 or 126 kg N/ha. One liquid (14–6–8) supplied the whole of the N and was either sprayed, combine-drilled or injected mid-way between the seed rows (15 cm apart). The other liquid (4–10–10) supplied one-fifth of the N and was either combine-drilled or injected; ‘Nitro-Chalk’ supplied the remainder of the N. The granular fertilizer (20–10–10) was broadcast.

The 14–6–8 solution always gave a smaller yield than comparable granules. Yields with injected dressings were no larger than with sprays, but each was safe. Combine-drilled dressings were harmful and often killed the barley and decreased yields especially when 126 kg N/ha was given.

The 4—10–10 solution was harmless when combine-drilled and gave a larger yield than the granules when 63 kg N/ha was given and the same yield when 126 kg N/ha was given. It gave a smaller yield than the granules when it was injected.

Grain percentage N tended to be larger with the injected liquids and smaller with the sprays than with the broadcast granules though the amount of N recovered by the barley from the injected liquids was no larger than from the granules.
Using highly saline irrigation water for a fodder barley crop
Authors: Hussain Z.
Published: March 2009

The aim of this investigation was to grow barley as a fodder crop under highly saline conditions. Saline irrigation waters with an electrical conductivity (EC) of 2·5, 4·0, 6·0 and 8·0 mmhos/cm respectively were used to irrigate test crops of barley over two growing seasons.

It was concluded that in general more highly saline water leads to a considerable increase in soil salinity even over a short period of growth, and a close control of soil salinity through leaching is required. Saline water with an EC of 4·0 mmhos/cm may be utilized without excessively high yield reductions if the soil salinity is well maintained. The saline waters with an EC of 6·0 mmhos/cm and 8·0 mmhos/cm may lead to yield reduction, and they require careful managmeent to control soil salinity build-up.
Short- and long-term effects of eating on blood composition in free-feeding goats
Authors: de Jong A.
Published: March 2009

Adult goats provided with permanent jugular and portal vein catheters were used to study the relation between spontaneous meals and blood composition in free-feeding goats in order to determine which constituents might fulfil a feedback signal function in the control of feed intake. Animals were fed ad libitum concentrates, supplemented with a small amount of hay. Blood samples were collected before, during and after spontaneous meals by means of a remote sampling system and were analysed for volatile fatty acids, glucose, insulin, glucagon and growth hormone.

In a preliminary experiment the relationship between body weight, voluntary feed intake, blood glucose and plasma insulin was examined in goats fed ad libitum concentrates and hay for 18 weeks. The data indicate a regulation of energy balance through control of feed intake. Since an increased glucose and insulin concentration was observed concomitantly with a decline in feed intake, glucose and/or insulin may fulfil a signal function in the control of energy balance.

Spontaneous meals were not preceded by a systematic change of any of the above blood constituents. Therefore, it is unlikely that meal initiation is governed by one of those. In contrast, spontaneous meals resulted in a rapid increase of insulin during eating (P < 0·025) whereas no clear changes were observed for the other substances. Thus, insulin might be a candidate for a feedback function in the control of meal duration.
Results from an experiment on permanent grass evaluating aqueous ammonia and aqueous urea, injected in bands either 30 or 60 cm apart
Authors: Penny A. , Widdowson F. V. , Ashworth J.
Published: March 2009

The experiment was on permanent grass at Rothamsted from 1974–75. ‘Nitro-Chalk’ (ammonium nitrate-calcium carbonate mixture, 25% N) broadcast in equal amounts for each of three cuts was the standard treatment against which the following were compared: (1) prilled urea (46% N) broadcast like ‘Nitro-Chalk’, (2) aqueous ammonia (26% N) injected in winter in bands 10 cm deep and either 30 or 60 cm apart, and (3) aqueous urea (18% N) injected like the aqueous ammonia. All these fertilizers were applied to give 250 or 375 or 500 kg N/ha in 1974 and all were reapplied in 1975.

In 1974 yields were larger with ‘Nitro-Chalk’ or prilled urea than with the aqueous fertilizers. Aqueous urea gave slightly larger yields than aqueous ammonia. Yields with the aqueous fertilizers were slightly larger when the injector knives were spaced 60 instead of 30 cm apart. Distribution of yield over three cuts was more uniform with ‘Nitro-Chalk’ and prilled urea (divided between cuts) than with the aqueous fertilizers. Injecting the aqueous fertilizers in bands 60 instead of 30 cm apart improved yield distribution only a little. In 1975 yields were slightly larger with the aqueous fertilizers at the first cut, but not in the drought afterwards.

Relative yields over the 2 years (‘Nitro-Chalk’ = 100%) were: prilled urea, 97; aqueous urea in 60 cm bands, 96; aqueous urea in 30 cm bands, 95; aqueous ammonia in 60 cm bands, 92; aqueous ammonia in 30 cm bands, 90.

In 1974 the grass recovered most N from ‘Nitro-Chalk’ and least from aqueous ammonia, but more from aqueous than from prilled urea. Recovery of N from the aqueous fertilizers was larger when injected in bands 60 instead of 30 cm apart, especially when 250 or 375 kg N/ha was given. Little rain fell in summer 1975 and recoveries of N were smaller than in 1974. The grass recovered more of the injected than the broadcast N, but no more with the injector knives 60 instead of 30 cm apart.
The combined use of fertilizer nitrogen and white clover as nitrogen sources for herbage growth
Authors: Reid D.
Published: March 2009

An experiment is described which investigated the combined effects of fertilizer nitrogen and a medium-large-leaved variety of white clover on the production from a mixed sward. Over a period of 3 years six rates of nitrogen fertilizer ranging from 0 to 750 kg/ha were applied annually on three different sward types cut five times per year. The swards consisted of S. 23 perennial ryegrass alone, S. 23 ryegrass plus Blanca white clover, and Blanca white clover alone. Averaged over the 3 years the nitrogen rate required on the pure-grass sward to give the same yield of dry matter as the grass plus Blanca clover sward with no fertilizer nitrogen applied was 265 kg/ha; the corresponding application rate to achieve equal crude-protein yield was 322 kg/ha. Blanca had an additive effect on the yield from the mixed sward at nitrogen rates up to at least 300 kg/ha. The results from this experiment are compared with those from experiments in which medium-small-leaved varieties of white clover were used. The role of white clover in providing savings in nitrogen fertilizer input on grassland is discussed. Estimates from the results indicate that the nitrogen rates required to produce an annual herbage dry-matter yield of 12 t/ha were 340 kg/ha on the pure ryegrass swards, and 140 kg/ha on the ryegrass plus Blanca sward. The nitrogen fertilizer saving due to the inclusion of Blanca white clover in the sward was, therefore, 43%. A similar estimate from the results of an earlier experiment with the medium-smallleaved variety Aberystwyth S. 100 suggests a nitrogen fertilizer saving of 21%.
Iron equilibrium in submerged soils as influenced by green manuring and iron application
Authors: Thind H. S. , Chahal D. S.
Published: March 2009

A pot experiment was made to study the effect of green manuring and iron application on the pE, pH, Fe concentration and iron equilibria in a calcareous and a noncalcareous soil. Green manuring drastically decreased the pE and pH and increased the Fe concentration of the equilibrium soil solution to a greater extent than submergence alone. Addition of Fe decreased pE, pH and increased Fe concentration both with and without green manuring. In calcareous soil pE and pH were high and Fe concentration was low compared with non-calcareous soil. In the absence of green manure and added iron, although there were wide variations in pE, pH and Fe concentration, Fe(OH)3-Fe2+; Fe3(OH)8-Fe2 + and Fe(OH)3-Fe3(OH)8 systems were controlling the solubility of Fe after 1 week of submergence in both the soils. But on green manuring all the above systems in calcareous soil and only Fe(OH)3-Fe3(OH)8 system in non-calcareous soil were operating at 1 week of submergence and continued afterwards. Addition of iron, with and without green manure, failed to bring an appreciable effect on these systems in calcareous and as well as in non-calcareous soil.
Estimation of the dry-and organic-matter intake of young sheep grazing a dry Mediterranean pasture, and their maintenance requirements
Authors: Benjamin R. W. , Chen M. , Degen A. A. , Aziz N. Abdul , Hadad M. J. Al
Published: March 2009

The organic matter intake of two breeds of sheep grazing a dry medic pasture was estimated by five different methods. The methods used were the calibrated weight estimate for measuring available herbage before and after grazing; a total faeces collection and digestibility trial; a tritium dilution technique; an established ratio of dry-matter intake to water intake; and an estimation using established energy requirements and the estimated metabolizable energy of the pasture. All methods gave similar estimates. It was concluded that the tritium dilution technique was the most useful method and that the dry-matter intake to water intake ratio was the easiest technique to use. The relative merits of the different methods used are discussed. The maintenance requirement for grazing German Mutton Merino and Awassi sheep was found to be 0·64 MJ ME/day/kg W0·75. When both breeds were caged in an open field the maintenance was 0·37 MJ.
Studies on ewe's milk
Authors: Ashton W. M. , Williams Myrtle , Ingleton Jean
Published: March 2009

This paper reports a continuation of previous work on the mineral constituents of ewe's milk, in particular copper, iron, manganese and zinc. Milk taken at weekly intervals from four groups of Clun Forest and Suffolk x Clun Forest ewes was studied over lactations varying from 6 to 12 weeks. The copper content showed a marked decline as the lactation advanced, while there was no consistent trend in iron content. Maximum, minimum and mean values for iron and copper are given for the sheep in each group.

Manganese was determined in the milk from two groups and zinc in. that from one group of ewes. There were significant differences in weekly manganese content in both groups, but no consistent trend as lactation advanced. Zinc content showed no significant differences from week to week, but the milk of one ewe was consistently very much lower in zinc than that of the other five sheep.
Comparison of direct drilling, reduced cultivation and ploughing on the growth of cereals: 3. Winter wheat and spring barley on a calcareous clay
Authors: Ellis F. B. , Elliott J. G. , Pollard F. , Cannell R. Q. , Barnes B. T.
Published: March 2009

Mouldboard ploughing, deep and shallow tined cultivation followed by conventional seed-bed preparation, and direct drilling were compared from 1972 to 1976 on a calcareous clay soil in two experiments, one on winter wheat and the other on spring barley.

At sowing the moisture content, bulk density and resistance to penetration in the surface layer of soil of uncultivated land were all greater than in soil that had been ploughed or cultivated deeply. Below 10 cm moisture content was less and root penetration was greater in the uncultivated soil. In all years winter wheat established and yielded well following direct drilling and shallow cultivation. In two dry autumns wheat establishment following ploughing was slower and less complete than with direct drilling, and in 1 year the yield was less. Spring barley established and yielded well without consistent differences in all years with all treatments.
Breed, nutritional and heterotic effects on age of teeth emergence in cattle
Authors: Brookes A. J. , Hodges J.
Published: March 2009

Under experimentally controlled nutritional levels, using Hereford, Hereford x Dairy Shorthorn, Dairy Shorthorn and Friesian breed-types, 288 animals were studied for age of eruption of the four pairs of front permanent teeth. Standard deviations are similar to those of other reports on Bos taunts. Breed differences were negligible and there is no evidence of heterosis. Lower nutritional levels delayed and higher levels advanced eruption. This effect had a maximum difference of 72 days if the differential nutrition was applied in calfhood. Differential nutrition later produced a smaller effect. It is concluded that in practice, the age of teeth eruption cannot be used to determine accurately the previous nutritional status of individual animals.
Effect of sulphur in rain on the growth and sulphur responses of oats in pot cultures
Authors: Scott N. M.
Published: March 2009

Until recent years large incidental additions of sulphate in fertilizers, especially superphosphate and ammonium sulphate, ensured that the major sulphur requirements of crops were adequately met. Increasing purity and concentration of commercial fertilizers, however, have largely eliminated such additions, with corresponding increase in the importance of available soil sulphate and atmospheric sulphur. The latter can readily be measured but its contribution to crops is more difficult to assess. To examine one aspect of this question, the effect of sulphur in rain on the yield and sulphur content of oats has been measured by comparing pot cultures grown in two environments, one with access to both gaseous atmospheric sulphur and rain sulphur and the other to gaseous sulphur only.
Assessing the reliability of rainfall if monthly falls are not independent
Authors: Glover J. , Robinson P. , Taylor J.
Published: March 2009

Glover & Robinson (1953) showed that for practical purposes the rainfall at a station in any month of the year can be assumed to be normally distributed, and that the probability of the rainfall being above a certain minimum value (selected with regard to crop requirements) can be calculated accordingly. If the rainfall in any one month is distributed independently of the rainfall in other months of the year, or season, then the probability of a pattern of rainfall month by month can be calculated by multiplying the several probabilities of the individual months. It was suggested that, in general, this was sufficient; but a method was given for obtaining the probability of a given pattern when association existed between the different months. In this the correlated monthly rainfalls, xi, were transformed to uncorrelated variables Yi. The value of each Yi, when all xi take their minimum values, was calculated and called ‘minimum Y’. The probability that each Y would exceed this ‘minimum Y’ was calculated and the probabilities multiplied.
An apparatus for measuring the motility of sperm cells
Authors: Bosselaar C. A. , Spronk N. , van Dam G. C.
Published: March 2009

1. A short description is given of an apparatus that aims at measuring the motility of sperm cells in an objective way.

2. In this method it is necessary to know the concentration on the slide for the determination of the value that indicates the motility. It was intended to measure this concentration with the same apparatus.

3. The measurement of the concentration met with some difficulties. A large scatter in the results was observed. This scattering is partly apparent in that it is caused by real differences in the concentrations which originate in the preparation of the slides. However, this apparent scatter hinders the determination of the exactness of the measurements. An estimate has been obtained, among other things, by means of a photographic experiment. There is some justification for expecting that a sufficient exactness can be obtained.

4. Notwithstanding the unexplained, and for the present still undoubtedly too large a scatter in the concentration measurements, a series of measurements of motility were made. The motility appears to be measurable by the apparatus, but there is still too great an error, so that the measurement does not yet come up to the visual method.

5. An effort to measure motility independent of the concentration on the slide (determination of the speed histogram) did not succeed because facilities were not available.
Nutrient interactions in pig nutrition I. Factors affecting the response to vitamin B12 in growing pigs
Authors: Carpenter K. J. , Duckworth J. , Lucas I. A. M. , Shrimpton D. H. , Walker D. M.
Published: March 2009

1. Growth and feed conversion efficiency of pigs between weaning and 100 lb. live weight were improved by adding a vitamin B12 a supplement to simplified all-plant rations containing, principally, barley and groundnut meal. This response was obtained with less than one-third of the U.S. recommended allowance of vitamin B12 in the rations of growing pigs.

2. No such response was obtained when a vitamin B12 supplement was added to rations containing milling by-products and grass meal.

3. When pigs were fed to a scale based on live weight, those that received an all-plant ration (containing milling by-products and grass meal, and relying on groundnut meal as the main source of supplementary protein to give a total content of 18·4 to 18·8% crude protein) gave 90–93% as good growth as pigs that were fed rations of similar total digestible nutrient content containing 14·5–15·5% crude protein and 3·6 or 7·0% white fish meal. Calculations suggest that such groundnut meal rations may be slightly deficient in lysine, but probably not deficient in tryptophan or ‘cystine + methionine’.

4. When pigs were fed to appetite, those that received rations containing 3·6% white fish meal and no milling by-products or grass meal, ate significantly more than those that had either ‘milling by-products + grass meal’ or no fish meal in their rations; they grew proportionately faster, with no improvement in the efficiency of feed conversion.

5. The carcasses of pigs that had received all-plant rations from weaning to bacon weight were of good quality, and their measurements did not differ from those of pigs that had received fish meal to 100 lb. live weight.
Response of growing steers to monensin sodium supplementation and implantation with trenbolone acetate and hexoestrol
Authors: Galbraith H. , Paterson G. F. M.
Published: March 2009

Current means of improving the efficiency of beef production in the United Kingdom include the use of hormonal anabolic compounds and the feed additive monensin sodium (monensin, ‘Romensin’, Elanco). Results from studies conducted mainly in the United States have shown that monensin may improve food conversion efficiency (e.g. Broome, 1980) which occurs as a result of variable reductions in food intake with or without increases in growth rate. These effects have been associated with alterations in the production of volatile fatty acids and methane in the rumen. Other studies have suggested that protein metabolism may also be affected (e.g. Pendlum, Boling & Bradley, 1980).
Some factors affecting the voluntary intake by pigs of diets containing effluent from the ensilage of grass
Authors: Patterson D. C. , Walker N.
Published: March 2009

Three experiments were carried out to investigate factors which might affect the voluntary intake of effluents.

Effluent was introduced into the diet of pigs at rates of 25, 50 and 100 g D.M./day, replacing dry meal to maintain a constant amount of dry matter offered. The mean maximum daily intakes of effluent on the three treatments were similar indicating that, within this range, the rate of introduction of effluent had no effect on its potential maximum intake.

When solutions with differing concentrations of effluent dry matter were offered it was found that the intakes at the 20 and 10 g/kg concentrations were progressively lower than when tho concentration was 30 g/kg or higher. This suggested a physical limitation to the intake of effluent at low concentrations. A physiological limit may operate at concentrations of 30 g D.M./kg or higher.

In the third experiment daily air-dry meal allowances of 80, 90, 100 and 110 g/kg W0.75 were offered in addition to an ad libitum supply of effluent. The voluntary intake of effluent dry matter was not significantly affected by tho amount of meal offered and the total amount of dry matter consumed remained virtually constant.
Growth performance and metabolic changes in lambs and steers after mild nutritional restriction
Authors: Thomson E. F. , Bickel H. , Schürch A.
Published: March 2009

Two trials investigating compensatory growth are reported in which lambs and young cattle were placed on either a continuous (C) or a discontinuous (RR) growth path. RR animals were subjected to a phase of restricted feeding and then realimented at an equivalent level of feeding to C animals over the same live-weight range. Eight 4-month-old lambs and 30 9-month-old Swiss Brown steers were used. The restriction (I) and realimentation (II) phase covered the live-weight ranges 23–32 kg and 32–44 kg respectively in tho lamb trial and 236–310 kg and 310–460 kg respectively in the steer trial.

Fifty-six total energy balances were made with lambs using open-circuit respiration calorimetry. Fifty determinations of diet digestibility and N balance were made with steers. Lambs received a pelleted concentrate diet and, except for restrictively fed steers which received hay alone, steers were offered a diet based on maize silage.

The restriction phase of RR lambs and RR steers was longer, and the daily ME intake and daily live-weight gains were significantly lower than those of the C animals.

Compared with C lambs a marked reduction in methane production of RR lambs occurred during feed restriction which persisted throughout realimentation.

During recovery realimented lambs gained non-significantly, but realimented steers significantly, more than C animals from a similar ME intake and required less ME/kg daily live-weight gain. Realimented lambs retained more protein at the start of recovery compared with C lambs but both C and realimented steeis retained similar amounts of nitrogen. Indirect evidence is presented that suggests improved utilization of ME for protein deposition, at least at the start of realimentation.

Although the animals on the discontinuous growth path (RR) took longer to reach slaughter weight, their total intake of gross energy and overall energy conversion ratio (MJ ME/kg live-weight gain) was similar to those of animals on the continuous growth path (C).
Tuber development, storage and germination in yams (Dioscorea spp.) in response to pre-harvest application of plant growth regulators
Authors: Wickham Lynda D. , Passam H. C. , Wilson L. A.
Published: March 2009

When pre-harvest foliar applications of growth regulators were made to vines of Dioscorea esculenta cv. Chinese Yam and D. alata cv. White Lisbon there were no obvious effects on tubers of D. alata, but dramatic effects on tuber development, storage and germination were obtained with D. esculenta tubers. Gibberellic acid caused marked extensions in tuber dormancy, 2,4-dichlorophenoxyacetic acid resulted in marked callus development, delayed germination and abnormal shoot and root development and indole acetic acid resulted in fingering of the tubers. It was concluded that there was potential for commercial exploitation of pre-harvest gibberellic acid treatments in extension of dormancy in Chinese Yam tubers and that the lack of response of D. alata tubers to foliar application of growth regulators warranted further investigation.
The effect of natural selection on composite cross populations of oats (Avena sativa) grown at contrasting sites in Scotland
Authors: Phillips M. S. , Powell W.
Published: March 2009

Three composite populations of oats were grown at contrasting sites in the north, east and west of Scotland for four successive generations from F3 to F6. Analyses of variance and canonical analysis both showed that the genetic constitution of the composites was responsible for a greater proportion of the variation than locations (sites). This suggests that either natural selection was not operating to any great extent or the effect of natural selection was very similar at the three sites. These findings were supported when selections were taken from one of the populations and subjected to canonical analysis. The implications for oat breeding in Scotland are discussed.
The assessment of populations of the aphid Sitobion avenae in field trials
Authors: Lowe H. J. B.
Published: March 2009

Variation in infestation of S. avenae on plots of wheat was assessed by combining techniques of enhancing field infestations with scoring individual shoots according to the number of aphids on them, using a logarithmic scale with base 2. The mean score appeared the most useful way of describing the aphid infestation on each plot.

In 1982, the sampling effort required for assessment of S. avenae on many plots was considerably reduced by this approach. The artificial increase in numbers of aphids avoided problems associated with sampling small populations, and the logarithmic classification of shoots reduced the time needed to assess large numbers. Scoring plots as a whole, although much quicker, gave results that differed from the assessments based on shoot sampling, and should be used with caution. The differences observed among cultivars in infestation of adult plants in the field in 1982 were not always the same as those observed on younger plants in the glasshouse.
The effects of several husbandry factors on the growth and yield of winter-sown barley at four sites in each of three years
Authors: Evans S. A. , Hough M.
Published: March 2009

Experiments testing the effects of variety, sowing date, seed rate, amount and time of application of nitrogenous fertilizer in the spring, application of nitrogenous fertilizerin the autumn and disease control at four sites in the north of England in 1980, 1981 and 1982 are described and the results are discussed.

The siting of the experiments and the seasons had important effects on grain yield and influenced the response to the total amount of nitrogen used and to disease control. The other husbandry factors produced more consistent effects. The choice of variety and drilling date had thegreatest influence on yield. The responses to the different seed rates, to the method of applying nitrogenous fertilizer and to autumn-applied nitrogen were smaller. The effects were additive.

It is argued that differences in the efficiency of light interception by the foliage affects grain yield; that light interception may be influenced by the state of the foliage at the start of the period of rapid growth from April onwards; and that site, season and husbandry all affect the development of the crop up to that point.
Effects of white clover and fertilizer nitrogen on herbage production and chemical composition and soil water
Authors: Wilman D. , Hollington P. A.
Published: March 2009

Effects of seven levels of N application and three seeds mixtures were studied on two sites for 4 years. One seeds mixture comprised perennial ryegrass (Lolium perenne L.) and two comprised perennial ryegrass with white clover (Trifolium repens L.). One site (Trefloyne) was 24 m above sea level on deep soil and the other (Pwllpeiran) was 328 m above sea level on relatively shallow soil. The plots were cut seven times per year.

White clover grew very strongly at Trefloyne in the first 2 years, fixing 350 kg N/ha/year where no N was applied; the clover declined very markedly during the 3rd year and there was very little in the sward in the 4th year; quite large quantities of clover were harvested in the 1st year even where 600 kg N/ha were applied. At Pwllpeiran the yields of clover were never high, but the clover persisted well where no N was applied. At Trefloyne the indirect contribution of the clover (in increasing the yield of grass) was greater in the first than in the second half of the year; clover was later than grass to grow strongly in the spring, but the extra grass growth compensated for this, so that the seasonal distribution of total herbage yield was similar on a grass-clover sward receiving no fertilizer N to that on a grass sward receiving six applications of N per year. At Pwllpeiran, on the other hand, the indirect contribution of the clover tended to be greater in the second than in the first half of the year where no N was applied.

The olover was similar to grass in phosphorus and potassium content and higher than grass in calcium and nitrogen. The clover was higher in nitrate-N content than grass grown without clover, at low levels of applied N, and increased the nitrate-N content of the grass growing with it.

Water consumption at Trefloyne was greatest on swards which contained olover and on the swards without clover which received at least 400 kg N/ha/year. The effect of clover on soil water was apparent particularly in the lower horizons of the soil.
The maintenance requirement of the fattening cockerel with a note on a proposed new method for the determination of the surface area of birds
Authors: Southgate B. A.
Published: March 2009

(1) The maintenance requirement of Light Sussex cockerels has been found by a feeding trial and comparative slaughter method. The maintenance requirement found was 22.1 calories per sq. m. of surface per hour. The net energy of the ration fed (Sussex ground oats: whole dried milk = 13 : 3) was 1.8 calories per gm.

(2) A new method of determining the surface area of birds is described.

(3) The value of K in the equation area = K has been found by this method to be 9.3.
Note on the chemical composition of bovine follicular fluid
Authors: Lutwak-Mann C.
Published: March 2009

1. Follicular fluid was collected by aspiration from the ovaries of cows which had been treated with pregnant mare serum, and were killed 3–4 days after heat.

2. Various chemical determinations have been carried out with samples of follicular fluid which, amongst others, was found to contain 39–43 mg./ 100 ml. of glucose, between 13 and 95 mg./100 ml. of lactic acid, and 0·8–3·0 mg./100 ml. of ascorbic acid.

3. The effect of follicular fluid upon sperm fructolysis was examined; however, no effect other than that due to the glucose content of the follicular fluid, could be observed.
Comparative performance of calves from Bunaji (White Fulani) dams and Gharolais, three-quarter Friesian and Bunaji sires
Authors: Johnson A. O. , Bell T. D.
Published: March 2009

Comparative evaluation was made on the live weight and growth pattern of calves from Bunaji (White Fulani) cows sired by Charolais, three-quarters Friesian crossbreds (three quarters Friesian and one quarter Bunaji) and Bunaji bulls in 2 years. Twelve steers per breed were evaluated on carcass merit after 250 days postweaning feeding.

Results showed that the Charolais half-cross and the Friesian three-eighth calves were heavier by up to 7, 23, 57 and 51 kg respectively at birth, weaning, 112 and 250 days after weaning than the Bunaji calves. The carcass data indicated superior slaughter weight and loin eye area in favour of the cross - breds, but no differences were found for dressed weight, dressing percentage, carcass grade and hide weight percentage among the breed groups. Carcass retail cuts showed heavier sirloin steaks and round steaks in favour of the cross-breds also.

The results were indicative of the superior growth of the cross-breds and underlined their carcass potential which may be useful in upgrading the indigenous stock. In view of the small numbers of progeny per sire group, especially among the cross-breds, further work needs to be done to confirm the present trend.
Heat-induced changes in dry weight, leaf size and number of chloroplasts per cell in maize and cowpea shoots
Authors: Adelusi S. A. , Lawanson A. O.
Published: March 2009

When etiolated seedlings of maize and cowpea were subjected to a heat stress of 45 °C for 8 h and subsequently illuminated, there was a retardation in the rates of leaf elongation and chloroplast formation, but the rate of increase in dry weight was not affected. However, a heat stress of 45 °C for 16 h decreased all the three rates measured, the effects being more pronounced with the longer duration of stress in the case of leaf elongation and chloroplast formation. The cowpea seedlings were more sensitive to heat than the maize seedlings. The decreased yield (dry weight) in the 16 h treatment was due, at least partly, to the heat-induced retardation of the growth of the photosynthetic apparatus.
Effect of l-mimosine in artificial diet on the growth and development of Heliothis punctiger larvae
Authors: Elliott R. , Milton J. T. B. , Gordon G. H. , Blamey F. P. C.
Published: March 2009

Major economic losses in many agricultural crops have been attributed to damage caused by insects of Heliothis spp. For example, Alcock & Twine (1980) estimated that in Queensland, Australia the annual losses caused by Heliothis spp. were over $16 million, with major losses in sorghum, cotton, tomatoes, tobacco, and safflower. The increasing resistance of Heliothis spp. to pesticides together with an increasing awareness of environmental problems associated with excessive use of pesticides has encouraged the development of research into the area of host-plant resistance. Naturally occurring toxicants and repellants, feeding deterrents and sex pheromones have been evaluated for some years (Jacobson, 1982; Lukefahr, 1982).
Studies on carotene in relation to animal nutrition: Part I. The technique of carotene estimation in feeding stuffs
Authors: Seshan P. A. , Sen K. C.
Published: March 2009

A modified method of estimating the carotene content of plant material has been described in detail. The modifications include a combined aqueous and alcoholic potash hydrolysis of the original material before extraction is carried out.

A statistical analysis and a recovery test have shown this method to be relatively more efficient than methods similar to those described by other workers.
Experiments on the use of chronic gonadotrophin (pregnancy urine extract) for the treatment of sterility in dairy cattle
Authors: Bottomley A. C. , Folley S. J. , Scott Watson Helen M.
Published: March 2009

1. The fertility of three sterile bulls was restored by injections of human pregnancy urine extract (P.U.).

2. Cows which failed to exhibit oestrus were treated by injections of P.U. Three out of five cows responded within 24 hours to intravenous injections of 5 c.c. P.U. (2500 rat units) and one out of four to an injection of 3 c.c. P.U.

Two out of five cows responded immediately to a series of three intramuscular injections of 2 c.c. P.U. and one cow responded to a single intramuscular injection of 2 c.c. P.U. In addition four cows failed to respond immediately to four intramuscular injections of 2 c.c. P.U.

3. Evidence was obtained which shows that treatment with P.U. at the time of service increases the fertility of cows which show regular oestrus but nevertheless fail to conceive. It is believed that this condition is often due (a) to failure to ovulate, and (b) to deficiency of progesterone following ovulation.

We are grateful to Prof. R. Rae and Mr K. W. C. Campbell for their co-operation. Part of this work was carried out during the tenure by one of us (H.M.S.W.) of a Research Grant from the Ministry of Agriculture and Fisheries.
The hydrogen-ion concentration of the semen of the bull
Authors: Anderson J.
Published: March 2009

1. The mean pH of 221 ejaculates of clinically normal bulls was 6·73 ± 0·020. Significant differences were noted between different bulls.

2. There were highly significant negative correlations between the pH. of the ejaculates and the concentration of spermatozoa, the volume of ejaculate and the motility of the spermatozoa.

3. The more acid the semen was on collection, the better was the motility retained on storage. Semen which retained its motility well became increasingly acid during storage. A change in the pH in the alkaline direction during storage had an adverse effect on motility. The more acid the pH on collection the less likely was a decrease in acidity during storage.