bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of supplementary winter feeding on the total yield and lactation curves of cows in a herd of British Friesian cattle
Authors: Wood P. D. P. , Newcomb R. 
Published: March 2009

SummaryA tightly autumn-calving herd of British Friesian cattle, running throughout the year as a single group, received two different amounts of mineralized barley supplement per day during the winter of 1973/4. As they calved, alternate cows were allocated to one of two rates of supplementary feeding differing in the approximate ratio 2:3 which was applied according to the calendar and not specifically related to milk yield.Average herd size for the year was 140 cows; average milk sales were 4680 kg/cow at a total supplementary concentrate use of 650 kg/cow. All cows had free access to selffeed silage reinforced with brewers' grains. Cows which received 50% more supplement from 8 September to 31 January (an extra 235 kg/cow) showed an improvement in total lactation milk yield of 248 kg/cow. Standard lactation curves were used to demonstrate a significant interaction between quantity of concentrates fed and season of production and showed that most of the improvement took place during the winter period.
ARC protein standards for growing pigs (including a comparison between field trial approach and replication at a single centre)
Authors: Braude R. , Hosking Zena D. 
Published: March 2009

SummaryResults of a co-ordinated trial carried out at 20 centres indicated that increasing the dietary crude-protein percentage by 2·5 and the lysine by about 0·2 over the ARC recommended levels failed to improve performance or carcass quality, whereas decreasing these nutrients to a similar degree below the recommended levels adversely affected performance and carcass quality.At four centres there were six to eight replicates. Substantial differences in estimates of both the level of response to a given treatment and the magnitude of treatment effects were observed between individual centres.Factors affecting the size of these co-ordinated trials are discussed.
Nitrogen response and stocking rate of Pennisetum clandestinum pastures: I. Pasture nitrogen requirement and concentration, distribution of dry matter and botanical composition
Authors: Mears P. T. , Humphreys L. R. 
Published: March 2009

SummaryAmmonium nitrate was applied to a kikuyu (Pennisetum clandestinum) dominant pasture at annual rates of 0, 134, 336 and 672 kg N/ha. Each nitrogen (N) rate treatment was continuously grazed at three stocking rates (SR) designed to apply similar grazing pressures at each N level and covering a range from 2·2 to 16·6 Angus weaner cattle/ha.The N status of these pastures was periodically assessed 8–10 weeks after seasonal N applications by temporarily excluding stock and measuring D.M. and N response to additional ammonium nitrate application. Pasture growth response to additional N was constant and independent of SR and of annual N rate over the range 0 to 336 kg N/ha, despite wide variation in pasture availability. N concentration of plant shoots was increased by high SR and rate of N uptake was not significantly affected by SR. Pasture growth rate was positively related to annual N rate.Herbage yield of kikuyu leaf, stem and litter on offer, was negatively related to SR but weight of underground organs was unaffected. Increasing SR increased the proportion of leaf and the rate of tillering. Pasture availability was positively and linearly related to N rate from 0 to 336 kg N/ha and maximal at 336 kg N/ha; the size of the litter fractions and underground organs was generally independent of N rate. N% in leaf and stem was reduced at low SR; N% of leaf, stem, litter, rhizome and root was positively related to N rate which was more influential than SR. The effect of SR on the size and relative distribution of the N in plant tops and litter fraction is discussed.Kikuyu dominance was positively related to N rate and independent of SR. White clover invaded at No and N131 levels especially at a high SR.
Further studies on the utilization of nitrogen in silage based diets
Authors: Griffiths T. W. , Smith F. H. 
Published: March 2009

SummaryTwo digestibility and balance experiments were carried out using 12 growing heifers to compare first and second cut silages fed alone or with supplementary barley or barley and urea, and to measure the effects of the addition of urea to silage and barley diets at three levels of dietary energy.Digestibility of gross energy (GE), N and modified acid detergent fibre (MADF) was higher in first cut than second cut silage diets, and although D.M. intake was slightly lower, metabolizable energy (ME) intake was significantly higher. Inclusion of urea increased the apparent digestibility of N but had no effect on the intake of D.M. or ME. Nitrogen retention was significantly higher on first cut than second cut silage diets and was significantly increased by the addition of urea when N intake was low. The relationship between daily N retention (DRN), ME intake (DME) and digestible N intake (DAN) was represented by an equation of the form:DRN =C–2·164DME+0·447DAN–0·00512DAN2+0·0487DMExDAN,but when apparent biological value (ABV) of dietary protein was high DRN was linearly related to DAN. These equations were used to estimate requirements for digestible N. The results of rumen fermentation studies suggested that the response in DRN to urea inclusion could be partially explained by the low rumen ammonia values on silage and barley diets.
Causes of inter-varietal differences in susceptibility to sodium toxicity injury in Phaseolus vulgaris
Authors: Ayoub Ali T. 
Published: March 2009

SummaryVarieties of beans (Phaseolus vulgaris L.) were grown under both greenhouse and field conditions to determine the causes of inter-varietal differences in susceptibility to sodium toxicity injury. Varieties varied greatly in plant growth and survival on sodic soils under arid conditions. Environmental conditions were very important in determining differences in survival. Chemical analysis of plant parts indicated that varieties accumulated different amounts of sodium in the roots, stems and leaves. Sodium concentration in stems and leaves of sodium-tolerant varieties was controlled to a low level at lower degrees of injury.
The potential digestibility of leaf and stem fractions of grasses
Authors: Goto I. , Minson D. J. 
Published: March 2009

SummaryThe potential digestibility of leaf and stem fractions of Rhodes grass (Chloris gayana) and Pangola grass (Digitaria decumbens) were determined by incubating in vitro with rumen fluid for 4, 7, 11 and 14 days with reinoculation after 7 days. The mean drymatter solubility (DMS) of four leaf and four stem samples from the two species, increased from 53·6% after 4 days to 63·8% after 14 days with increases of 14·9 and 5·7% for leaf and stem respectively. Prolonged incubation of sheep faeces from these feeds gave similar patterns of DMS as those for the original feed.To determine the cause of the observed rise in DMS, leaf and stem of Rhodes grass was incubated for 21 days with rumen fluid and Onozuka cellulase. When using cellulose, DMS increased by 7·7% compared with 14·6% when using rumen fluid. The higher DMS with rumen fluid was associated with an increase in the mean disappearance of lignin from 33·6% at 4 days to 52·6% after 21 days. After 14 days there was no further loss of lignin from most samples indicating the existence of a hard resistant lignin core.It was concluded that when determining potential digestibility forages must be incubated with rumen inoculum for at least 21 days and that shorter incubation times may lead to biased conclusions.
Studies of some factors affecting the output of silk in Bombyx mori L
Authors: Gaaboub I. A. , Rawash I. A. , Mostafa S. M. 
Published: March 2009

SummaryThe results obtained showed that there was a clear relationship between the ability of larvae to assimilate mulberry leaves and the resulting cocoons. The mulberry varieties, Morus alba var. rosa, M. rubra and M. alba var. Ihu, had a conspicuous effect on weights of the resulting cocoons in the three races of silkworm (Novi, Belgharia 4 and S.A. 105) studied.Results obtained also indicated that the length of the silk fibre and the weight of silk cocoons that yielded 1 kg of silk were largest when the larval diet was M. alba var. rosa or M. rubra, and were smallest when the larval diet was M. alba var. Ihu.Results also showed that the protein content determined in the resulting silk was proportional to the protein percentage in the different mulberry leaves.Feeding of larvae of the races Novi, Belgharia 4 and S.A. 105 on M. alba var. rosa and M. rubra leaves caused approximately one- to twofold increase in the fresh weights of larvae or pupae. Weights of fresh cocoons and cocoon cortex constructed by pupating larvae were largest when larval diet was M. alba var. rosa or M. rubra and were smallest when the larval diet was M. alba var. Ihu.
An examination of the net changes in amino-acid composition within the rumen of mature wether sheep using canonical variate analysis
Authors: Fenlon J. S. , Beever D. E. 
Published: March 2009

SUMMARYData for the quantity of ammo acids consumed and their flow rates at the proximal duodenum for 33 diets fed to sheep have been statistically analysed by both univariate and multivariate methods. Analysis of variance of net loss (g/day) between mouth and duodenum of individual and total acida was not conclusive. Canonical variate analysis which takes regard of the correlations between different acids both within and between diets provided a conoise method of discriminating between diets. The advantage of this method in generating a unified account of digestion within the rumen is that it effectively reduces the problem from one of many dimensions to a situation where only the first few transformed variables need to be considered.
Winter leaching of nitrate from autumn-applied calcium nitrate, ammonium sulphate, urea and sulphur-coated urea in bare soil
Authors: Addiscott T. M. , Cox D. 
Published: March 2009

SummaryIn a flinty clay loam at Rothamsted, nitrate concentrations in 0–13 and 13–26 cm layers of plots given all N-sources at 100 kgN/ha in early October were very small by mid-January. Incorporating the fertilizer in the first 13 cm slightly accelerated this loss. Sulphur-coated urea (SCU) maintained smaller nitrate concentrations than other sources in both layers. By early March SCU plots alone had slightly larger nitrate concentrations than the controls in the 0–26 cm layer, whilst in the 26–52 cm layer all N plots had slightly larger concentrations than the controls. Spring barley, given no more N and harvested green at ear emergence, took more N from all N plots than from the controls, most from ammonium sulphate and least from urea and SCU, but differenoes between sources were not significant. The nitrate loss had a negligible effect on soil pH and exchangeable cations.Calcium nitrate leaching data were used to test the equation of Burns (1975) and other simple equations which considered the effects of successive percolations in a two-layer system assuming that the layers either could or could not become temporarily oversaturated. All the equations underestimated leaching unless the most inaccessible soil water was left out of the calculations and gave best results when only gravitational water was taken into acoount.
Quantitative digestion of fresh herbage by sheep
Authors: Egan A. R. , Ulyatt M. J. 
Published: March 2009

SummaryThe utilization by sheep of dietary N provided in high protein, high water content fresh herbages (Ruanui perennial ryegrass, Tama Westerwolds ryegrass, Pitau white clover, and Fakir giant sainfoin at two stages of maturity) was studied at two levels of intake (maintenance and 1·5 maintenance). Feed was provided by constant feeder.Apparent digestibility of N was similar for all herbages (ca. 85%) except sainfoin which, particularly at a late stage of maturity, was lower (70–80%). A small loss of nitrogen across the stomachs occurred with clover (1–3 g/day) and Tama ryegrass at the higher feeding level (2 g/day), but no loss was observed with the other diets. The apparent digestibility of N and of non-ammonia N (NAN) in the intestines was lower for sainfoin, and estimated true digestibility was also lower. Amino acid N contributed less to the NAN reaching the duodenum on the sainfoin diets than on the grass and clover diets.N retention was negative at the lower level of feeding for ryegrass and clover diets. It was greatest for the sainfoin diets at similar N intakes, so that efficiency of retention of apparently digested N was also greatest for sainfoin.The size of the urea pool, the plasma urea concentration and the urea irreversible loss, using [14C]urea, did not differ significantly between diets at similar N intake. Urea irreversible loss exceeded urinary urea excretion by 35—50% on all but the late-maturity sainfoin diet, where urea irreversible loss was more than double the urinary urea output. These data indicate dietary differences in the extent of degradation of urea on recycling to the gastro-intestinal tract. Urea clearance across the kidney was also lowest for sainfoin.Data are compared in a simple model which illustrates the importance of variable clearance of urea across the kidney and the gut wall and the need for knowledge of factors which control this.
The effect of host development on the field assessment of disease resistance to Cercospora leaf spots in groundnuts (Arachis hypogaea L.)
Authors: Nevill D. J. , Evans Alice M. 
Published: March 2009

SummaryIn previous studies of the reactions of groundnut varieties to infection with Cercospora arachidicola Hori and Cercosporidium personatum (Berk. & Curt.) Deighton, the existence of disease resistance has been demonstrated. However, these investigations have not resulted in the production of high yielding, disease resistant, varieties and it has been suggested that disease resistance is physiologically linked to low seed yield. In the present study, two aspects of the host–pathogen interaction were investigated: these were varietal response to chemical disease control, and the effect of plant sterility on host and pathogen development. It was found that a general score of resistance to leaf spot did not always relate to the varietal response to disease control and reasons for this were proposed. The prevention of pod production did not affect pathogen development, but vegetative growth of the treated plants was increased. It was concluded that host and pathogen development could be confounded during the assessment of disease resistance. In future varietal screening trials, the use of single branch comparisons should prevent this confusion.
Changes in the water status of tea clones during dry weather in Kenya
Authors: Carr M. K. V. 
Published: March 2009

SummaryPartial closure of the stomata occurred during the middle of the day even when tea plants were growing in a wet soil and there were similar diurnal changes in the xylem water potential (ψx). As the soil dried the daily minimum values of ψxdeclined, more in some clones than in others, and there were also interesting differences between clones in the sensitivity of their stomata to changes in ψx. Possible ways in which these observations could form the basis of tests for screening clones for drought resistance are discussed.
A simple technique for the short-term storage of pollen of a dihaploid-inducing diploid potato clone
Authors: De Maine M. J. 
Published: March 2009

SummaryTwo methods of storing pollen of the dihaploid-inducing Dutch (Wageningen) Solatum phureja clone, IVP 48, are described. Pollination results showed that the functional fertility of one type of stored pollen is similar to that of fresh pollen when used in dihaploid induction crosses on tetraploid potatoes. No obvious relationship was found between the in vitro germination of the pollen samples and their functional fertilities in dihaploid induction crosses.
Development of body components in Kenana cattle. 2. Relative weight changes of major carcass tissues
Authors: Gaili E. S. E. , Nour A. F. Y. M. 
Published: March 2009

SummaryThirty-two weaned Kenana bull calves were adequately fed to maximize growth and serially slaughtered at predetermined live weights of 100, 200, 300 and 400 kg. Eight animals were slaughtered at each slaughter point and the left side of each carcass dissected into individual muscles, bone, fat, tendons and fascia. Individual muscles were grouped into nine muscle groups and the distribution of intermuscular fat was studied in four anatomical regions. Huxley's (1932) allometric equation was used to describe the development of carcass tissues.Relative to overall carcass side growth, fat was the fastest developing tissue, followed by muscle and bone tissues in descending order. The muscles of neck + thorax and abdominal muscles exhibited the fastest rate of growth relative to overall total side muscle growth, and the distal muscles of both limbs exhibited the slowest rate of relative growth. Relative to the rate of side fat deposition throughout the experiment, subcutaneous fat was deposited at a faster rate than intermuscular or kidney + channel fat. Intermuscular fat was deposited at different rates in the anatomical regions of the carcass.The development of muscle groups was further examined in three arbitrary phases of the test period and revealed significant differences between phases in the rate at which each muscle group developed. Similar changes in the intensity of the rate at which fat was deposited in the subcutaneous region and between the muscles of the carcass or sites were evident.Kenana cattle compare favourably with foreign dairy and beef breeds of cattle in muscle:bone ratio. Further studies are needed to evaluate the efficiency of meat production from Kenana cattle under different systems of management.As reported in Part 1 (Gaili & Nour, 1980) a study was conducted to investigate the development of body components in Kenana cattle and to evaluate the potential of the breed for meat production. This paper is an account of the data which were obtained on the development of carcass tissues.
An index of feather cover
Authors: Macleod G. D. , Clark J. A. 
Published: March 2009

SummaryAn index of feather cover is described and applied to assess the coats of various birds. Feather area indices were calculated, by analogy with the leaf area index used by crop ecologists, as the projected area of feathers above unit area of skin. Measurements were made on samples from chickens, turkeys, pheasants, sparrows and herring gulls. The index was calculated for feather tracts on six areas of the body. An overall area index was also calculated, based on the feather cover of at least 60% of the bird's body surface. Intra- and interspecific differences were large. Between species there was a positive correlation between feather index and body weight, while within species, for poultry at least, the opposite was found. This characterization of the feather coat is discussed in terms of its possible use as an index of the insulation of feathers.
Response of wheat to zinc and its critical level in Old Alluvium soils
Authors: Singh A. P. , Sakal R. , Thakur K. N. , Sinha H. 
Published: March 2009

SummaryA pot culture experiment with 30 Old Alluvium soils was conducted to evaluate the critical Zn concentration in soils and wheat plants for predicting the response to Zn application. The DTPA-extractable Zn (available Zn) in these soils ranged from 0·37 to 4·50 mg/kg soil, and total Zn in the wheat plants of the control pots ranged from 17 to 65 mg/kg wheat shoots. The DTPA-extractable Zn was found to be positively correlated with organic carbon (r = 0·72, P < 0·01), negatively with pH (r = –0·48, P < 0·01) and positively with wheat tissue Zn concentration (r = 0·98, P < 0·01). The Bray's ‘per cent’ yield value was positively correlated with ‘available’ Zn (r = 0·82, P < 0·01) and plant tissue Zn (r = 0·85, P < 0·01). The critical concentration of Zn in soil and plant below which responses to applied Zn may be expected was 0·65 mg Zn/kg soil and 24·5 mg Zn/kg wheat shoots respectively. All the soils below 0·65 mg Zn/kg soil responded to Zn application where the ‘per cent’ response at 5mg added Zn/kg soil ranged from 22·65 to 100·00 with a mean value of 58·24 whereas at 10 mg added Zn/kg soil, it ranged from 13·08 to 97·14 with a mean value of 40·08. Soils above the critical limit negatively responded to Zn application.
Relative efficiency of rock phosphate and superphosphate for forage legumes and residual effects on succeeding wheat
Authors: Prasad R. , Singh A. 
Published: March 2009

SummaryA field experiment was made at the Indian Agricultural Research Institute, New Delhi to compare the efficiency of Mussoorie rock phosphate with ordinary superphosphate for two forage legumes, cowpea (Vigna sinensis Savi) and cluster beans (Cyamopsis tetragononoloba L.) and residual effects were studied in wheat (Triticum aestivum L.). For both the forage legumes Mussoorie rock phosphate was only 22% as effective as ordinary superphosphate (on soil of pH 7·1) and it had no significant residual effects on wheat even when the application rates supplied three times as much P as was supplied by ordinary superphosphate.
Feeding trials with ammoniated molasses in the diet of young dairy cattle
Authors: Bartlett S. , Broster W. H. 
Published: March 2009

1. Ammoniated invert molasses when used as a food for yearling dairy cattle proved toxic in doses of 1 lb. per day.2. When ammoniated invert molasses had been acidified with phosphoric acid the toxicity was markedly reduced but not entirely eliminated. Ammoniated molasses acidified with acetic acid produced no toxic effects but the live-weight responses of yearling cattle was inferior to a ration markedly deficient in protein. The poor responses may have been partially due to the unpalatability of the ammoniated molasses.3. The ammoniated molasses used in experiment 1 did not produce toxic symptoms in rats but it did result in reduced food consumption and poor growth.4. The ammoniated molasses treated with acetic acid, when included at the rate of 10% of the diet of guinea-pigs, depressed appetite and caused toxic effects.
Utilization of low quality roughages: effects of alkali treatment of wheat straw on intake by and growth rate of cattle, with and without a supplement of cotton-seed meal
Authors: Sriskandarajah N. , Kellaway R. C. 
Published: March 2009

SUMMARYEffects of treating wheat straw with caustic soda solution and of providing a cottonseed meal supplement were studied with 40 Friesian heifers (280 kg live weight) in individual pens. Responses were measured in terms of food intake, growth rate and food conversion ratio.Wheat straw was coarsely-milled and fedad libitum, untreated (U) or alkali-treated (T); both types of straw were supplemented with urea and minerals. Half the animals on each type of straw were fed 500 g cotton-seed meal (C/day.Straw intake was higher with T than with U (P< 0·01) and unaffected by the cotton-seed meal supplement, being 4·53, 4·71, 6·58 and 6·56 kg/day on treatments U, UC, T and TC respectively. Alkali treatment and the cotton-seed meal supplement improved live-weight change (P< 0·001), being –6, 189, 334 and 495 g/day respectively.In vivodigestible organic matter in the dry matter, calculated from lignin ratios, was 59, 60, 64 and 64 respectively.Rumen VFA concentrations were significantly higher, molar proportions of acetic acid lower, propionic andn-butyrie acids higher in animals on T than on U. Plasma urea and rumen ammonia concentrations were lower on treatment T than on U.It was concluded that wheat straw which is coarsely-milled, NaOH-treated and sprayed with urea and minerals provides sufficient nutrients to allow cattle to grow and that additional gain obtained by feeding cotton-seed meal was predictable in terms of its energy contribution to the diet.