bluuebunny/crossref_metadata_2025_split huggingface dataset:
Short- and long-term effects of eating on blood composition in free-feeding goats
Authors: de Jong A. 
Published: March 2009

SUMMARYAdult 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

SUMMARYThe 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

SUMMARYAn 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

SUMMARYA 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

SUMMARYThe 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

SUMMARYThis 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

SUMMARYMouldboard 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

SUMMARYUnder 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

SUMMARYUntil 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.
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.
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

SUMMARYThree 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

SUMMARYTwo 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

SummaryWhen 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

SummaryThree 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

SummaryVariation 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

SummaryExperiments 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.