bluuebunny/crossref_metadata_2025_split huggingface dataset:
Water-soluble, exchangeable and nonexchangeable potassium in six soil series from tropical India
Authors: Rao A. Subba , Sekhon G. S. 
Published: March 2009

SUMMARYSix soil series differed in water-soluble, exchangeable and nonexchangeable K. Significant positive relationships were observed between exchangeable K and water-soluble K. A highly significant positive relationship was found between the K saturation of the cation exchange complex and water-soluble K in the individual soil series, and when the six series were pooled; K saturation, therefore, may predict water-soluble K in a range of tropical soils. Potassium desorbed in 35 min by electroultrafiltration (EUF) may serve as a measure of exchangeable K in predominantly kaolinitic tropical soils. In soils with appreciable amounts of mica, longer K extraction by EUF (up to 70 min) may indicate the reserves of nonexchangeable K.
Growth of lambs offered fixed amounts of roughage and concentrate either simultaneously, progressively or separately
Authors: Wilkinson R. G. , Greenhalgh J. F. D. 
Published: March 2009

SUMMARYTwo experiments were carried out to study the efficiency of energy utilization by Suffolk × Blackface lambs. In the first experiment, a digestibility trial, the lambs were fed on either a roughage (chopped dried grass), concentrate (whole barley, ground barley and fishmeal), or mixed (roughage and concentrate) diet. The dry matter (DM) and organic matter digestibility coefficients of the mixed diet were slightly, but not significantly, lower than the ‘expected’ values calculated by summation of the separately determined digestibility coefficients of the component feeds. Similarly, the metabolizable energy (ME) value was 1·6% lower than the ‘expected’ value.In the second experiment, lambs were offered 52·5 kg roughage DM (ME 9·96 MJ/kg DM) and 52·5 kg concentrate DM (ME 11·59 MJ/kg DM) as:(i) a mixed diet (M); (ii) a progressive change from roughage to concentrate (R–C); (iii) a progressive change from concentrate to roughage (C–R); or 105 kg roughage or concentrate DM as either (iv) a roughage diet (R), or (v) a concentrate diet (C). Lambs on treatments R–C, C–R and R and C combined took a similar time to consume their allocation of food and achieved a similar final empty body weight (EBW) and empty body composition. In addition, the total energy retention (ER) of lambs on these treatments was similar to that predicted by a feeding standards model for lambs of a similar liveweight offered diets of the same ME content. Lambs on treatment M consumed their allocation of food faster than those on all other treatments and achieved a slightly, but not significantly, higher final EBW, which contained a higher proportion of fat. The ER was higher than predicted. The higher overall efficiency of lambs on treatment M was attributed to higher daily intakes and differences in the ratio of protein: fat deposited and maintained by lambs on each treatment. The adoption of separate efficiency constants for both deposition and maintenance of protein and fat in current feeding standards would result in a more accurate prediction of animal performance.
Potential nutritive value of a wide range of grassland species
Authors: Wilman D. , Riley J. A. 
Published: March 2009

SUMMARYFifteen grassland species were grown in a heated glasshouse in February-April 1985. The harvested herbage was separated into leaf and ‘stem’ and analysed for neutral detergent fibre, digestibility, physical breakdown when macerated, fibrosity, water soluble carbohydrate and N, P, K, Ca, Mg and Na.Lolium perenne was digestible, but rather high in neutral detergent fibre and not readily broken down by maceration. The other grasses tested, Holcus lanatus, Poa annua and Glyceria fluitans, tended to be less digestible and higher in neutral detergent fibre than L. perenne.The leaves of all 11 dicotyledonous species were much lower in neutral detergent fibre than the leaves of the grasses, and most broke down readily when macerated. The stems of Medicago saliva and of two shrub species (Lonicera periclymenum and Prunus spinosa) were the highest in neutral detergent fibre.Rumex obtusifolius, Spergula arvensis and Stellaria media were high in Mg; Plantago lanceolata, S. arvensis and S. media were high in Na; and S. arvensis was high in P.Three perennial and two annual herbaceous, dicotyledonous non-legumes were selected as being of sufficient promise and interest to be compared with Lolium perenne in feeding experiments: Plantago lanceolata, Taraxacum officinale, Rumex obtusifolius, Spergula arvensis and Stellaria media.
Termination of flowering in ‘indeterminate’ faba beans (Vicia faba)
Authors: Stoddard F. L. 
Published: March 2009

SUMMARYThe duration of flowering was investigated in 14 accessions of indeterminate faba (field) beans (Vicia faba L.) planted near Adelaide, South Australia in 1986 and 1987. All flowers and young pods were removed from plants at 4–7 day intervals. Plants of ‘Mediterranean’ origin produced 20–30 flowering nodes while those of European ‘spring bean’ type produced up to 50. Terminal inflorescences were eventually produced in all accessions. In control plants, the number of days between anthesis at successive nodes was partly dependent on nocturnal minimum temperature and varied very little between genotypes. It should be possible to make best use of the growing season by optimizing the potential production of nodes, but there is little opportunity for manipulating the rate of their appearance.
Physical characteristics of the alimentary tract in relation to seasonal changes in voluntary food intake by the red deer (Cervus elaphus)
Authors: Sibbald A. M. , Milne J. A. 
Published: March 2009

SUMMARYVoluntary intakes of a medium-quality grass hay were measured in winter (early January) and in spring (late April) near Edinburgh for two separate groups of six red deer, together with digestibility and mean retention times of the particulate-phase marker, 103Ru-phenanthroline. The deer were then slaughtered and the weights of digesta and the dimensions of the alimentary tract were measured. Voluntary intakes of dry matter were significantly higher in spring than in winter, but there was no difference in digestibility or mean retention time of 103Ru-phenanthroline. There were no significant differences in any of the organ weights or the dimensions of the intestines between the groups slaughtered in winter and spring. Dry matter proportions of digesta in the rumen, abomasum, small intestine and caecum, the wet and dry weights of rumen digesta and the water-filled capacity of the rumen were significantly greater in spring.
Use of prolonged-release bovine somatotropin for milk production in British Friesian dairy cows. 1. Effect on intake, milk production and feed efficiency in two consecutive lactations of treatment
Authors: Phipps R. H. , Weller R. F. , Craven N. , Peel C. J. 
Published: March 2009

SUMMARYIn two consecutive lactations in 1985/86 and 1986/87, 60 cows were injected with 500 mg of Sometribove, methionyl bovine somatotropin (BST), or a placebo at day 60±3 post partum; injections were repeated fortnightly for the remainder of each lactation. All cows received the same complete diet (metabolizable energy (ME) 11·5 MJ/kg dry matter; crude protein 169 g/kg dry matter) ad libitum for the first 20 weeks of lactation, after which, energy concentration of the diet was reduced as yield declined.The administration of BST significantly increased milk yield by 4·3 (P < 0·001) and 3·1 kg/day (P < 0·05) in the first and second lactations, respectively. The mean dry matter (DM) intake of 16·3 kg/day in lactation 1 for the treated group was significantly (P < 0·01) higher than the 14·7 kg/day recorded for the control group. The response in intake was not significant until 6 weeks after treatment started. However, in the pretreatment period of the subseque1t lactation, the DM intake of the cows in the treated group was already significantly (P < 0·01) higher (+ 1·2 kg/day) than that of the control group. Although the DM intake in the treatment period of lactation 2 was also higher for the treated group, the difference from the control group was not significant.With the exception of a significant (P < 0·01) increase in milk protein (control 35·3 g/kg v. treated 36·3 g/kg) in lactation 1, overall milk composition was unaffected by BST treatment. The administration of BST increased apparent feed efficiency (kg 4% fat-corrected milk (FCM)/kg DM intake) by 6 and 10% and gross feed efficiency (kg FCM/MJ ME) by 8 and 6% in lactations 1 and 2, respectively.Animals treated with BST had significantly (P < 0·05) lower scores for body condition during the treatment period in lactation 1. This was, however, recouped during the dry period so that both groups had similar body conditions before the start of the next treatment period.BST administered every 14 days in a prolonged-release formulation increased the yields of milk and milk constituents and apparent and gross feed efficiency during two consecutive lactations of treatment.
Replacement of palm oil by thevetia oil in broiler chick diets
Authors: Atteh J. O. , Ibiyemi S. A. , Onadepo F. A. , Ugboma O. O. 
Published: March 2009

SUMMARYThe effects of replacing 0, 25, 50 or 100% of dietary palm oil (5%) with oil of Thevetia peruviana was investigated using broiler chicks 0–3 weeks old.Increasing the content of thevetia oil in the diet reduced average daily feed intake and weight gain (P < 0·05) and decreased protein and fibre retention (P < 0·05) and fat retention (P < 0·01). However, there was no significant effect on feed: gain ratio or mortality rate. It is concluded that there is a need for further processing of thevetia oil before it can be used effectively as an ingredient in broiler feed.
A comparison of the responses of two cultivars of late-autumn-sown wheat to applied nitrogen
Authors: Webb J. , Sylvester-Bradley R. 
Published: March 2009

SUMMARYAt four pairs of sites in the UK, two cultivars of wheat, bred either for autumn (cv. Mercia) or for spring (cv. Tonic) sowing were sown in November 1988 and 1989 and their yield response to springapplied fertilizer N assessed over the range 0–320 kg/ha N. Grain samples were taken at harvest and analysed for those qualities regarded as indicators of suitability for milling. In five experiments, the grain yield of Mercia was up to 1 t/ha greater than that of Tonic, but overall there was no consistent difference between the two cultivars in the optimum economic yield (Yopt)or in the amount of fertilizer N needed to produce it (Nopt). Both cultivars produced c. 17·5 kg of grain per kg of fertilizer N applied up to Nopl. In the five experiments in which Tonic yielded less, it produced grain of greater N concentration than Mercia when given the same amount of fertilizer N. Differences in grain N concentration, while small (< 0·3%), were significant when analysed across sites. In six experiments both cultivars produced grain of 11 % protein at Nopt. There were no consistent or worthwhile increases in specific weight, Hagberg falling number (HFN) or response to the sodium dodecyl sulphate (SDS) sedimentation test of either cultivar from applying more fertilizer N than Nopl. The average specific weight of Mercia grain was 2·5 kg/hi greater than that of Tonic, while Tonic gave larger SDS values of c. 8. There was little difference in HFN. It was concluded that the yield requirement for fertilizer N was similar for these two cultivars of wheat when sown in late autumn, and there was no need to apply differential fertilizer N applications to the cultivars to produce grain of the quality needed for breadmaking. In four experiments the application of plant growth regulator (PGR) increased the yields of both cultivars by c. 0·5 t/ha.
Physical structure of white clover, rape, spurrey and perennial ryegrass in relation to rate of intake by sheep, chewing activity and particle breakdown
Authors: Mtengeti E. J. , Wilman D. , Moseley G. 
Published: March 2009

SUMMARYFour plant species were compared in each of three harvest periods (in August/September) in 1991 and 1992 at Aberystwyth: white clover (Trifolium repens L.), rape (Brassica napus L.), spurrey (Spergula arvensis L.) and perennial ryegrass (Lolium perenne L.). Plant physical structure was considered in relation to rate of intake by sheep, chewing activity and the effectiveness of chewing in breaking the diet into particles.White clover had a much lower proportion of cell wall than perennial ryegrass, but the rate of intake and the number of chews per min were similar for the two species. White clover petioles broke down into long, thin particles, similar in size and shape to those derived from perennial ryegrass leaf sheaths; many of the clover petioles were not split longitudinally by chewing, in contrast to the ryegrass sheaths. A white clover leaflet was typically broken into about 20 blocky particles, whereas a petiole of similar weight was broken into only about three particles. Veins were close together in ryegrass leaf sheaths and blades, particularly the latter; approximately one in seven strips of weaker tissue between veins was ruptured by chewing leaf sheaths and one in 16 in the case of leaf blades, in each case resulting in particles of c. 2 mm width. Rape had a low proportion of cell wall and a low proportion of vascular tissue in its leaf blades, petioles and stems. Rape leaf blades were eaten quickly, but the stems were eaten slowly. The length and width of particles derived from rape leaf blades were very similar to those of particles derived from white clover leaflets. Spurrey had a high proportion of cell wall and was low in in vitro digestibility, but the rates of intake and chewing were high and relatively few chews were required per g of dry matter ingested. The vascular bundles in the spurrey stems were only half the thickness of the bundles in white clover petioles; pieces of spurrey stem were typically broken at about two places along their length and were not split during eating.The study illustrates the wide variation in plant anatomy among species which can be available to herbivores and some effects of the abundance, thickness and orientation of vascular bundles on rate of intake, chewing activity and the size and shape of particles produced by chewing.
Evaluation of the use of the purine derivative: creatinine ratio in spot urine and plasma samples as an index of microbial protein supply in ruminants: studies in sheep
Authors: Chen X. B. , Mejia A. T. , Kyle D. J. , Ørskov E. R. 
Published: March 2009

SUMMARYIn ruminants, the urinary excretion of purine derivatives (PD) reflects the absorption of microbial purines and can be used as an index of microbial protein supply. The objective of this study, carried out in Aberdeen, 1992, was to examine whether PD concentrations in spot urine or plasma samples vary diurnally during a given feeding regime and if they reflect differences in daily PD excretion induced by varying feed intake. Sixteen sheep were offered ad libitum one of four diets (fresh weight basis, the rest of each diet being minerals and vitamins): (1) 99·9% lucerne (pelleted); (2) 50% hay, 30% barley, 9% fishmeal and 10% molasses; (3) 72% straw, 7% molasses and 20% molassed sugarbeet pulp; and (4) 97% barley. Measurements were made for 1 week after a 2-week adaptation period. Urine was collected daily on days 1–4 and hourly on days 5–7. Hourly urine collection was achieved using a fraction collector. Plasma samples were collected hourly from 09·00 to 17·00 h on day 4. Feed intake varied considerably (347–1718 g DM/day) between diets and between animals. Daily excretion of PD (7·1–22·6 mmol/day) was linearly related to DM intake (r = 0·85, n = 16), and so was the microbial N supply (3·9–19·5 g N/day) estimated from daily PD excretion (r = 0·87). In hourly urine samples, the ratio of PD:creatinine concentrations showed no significant difference between sampling times, and was linearlycorrelated with the daily PD excretion (r = 0·92). Similarly, plasma PD concentration also showed little diurnal fluctuation. Glomerular filtration rate (GFR) increased with feed intake. Plasma PD was not well correlated with daily PD excretion in urine (r = 0·57). The tubular load of PD (plasma PD × GFR) was better correlated with the daily excretion (r = 0·80). It appears that when sheep are fed ad libitum, PD in spot urine may provide a practical indicator of microbial protein supply status.
Boron tolerance in wheat in relation to soil salinity
Authors: Manchanda H. R. , Sharma S. K. 
Published: March 2009

SUMMARYA screenhouse study in Haryana in 1986/87 evaluated the effect of boron on the wheat cultivar WH147 grown in pots in a sandy soil at three salinities. Before sowing, 0–9 mg B/kg soil was added. Without added B the crop produced significantly more grain at electrical conductivity of the saturation extract (ECe) 6 dS/m than at other salinities, but at ECe 8 dS/m yields were similar to those in nonsaline (ECe 0·8) soil. Grain yield in nonsaline soil was not affected significantly even at the highest concentration of added B, even though at the boot stage the shoots had accumulated as much as 307 mg B/kg. At ECe 6 and 8 dS/m, grain yield was significantly less with 3 and 1 mg added B/kg, respectively, than without added B, even though the B concentration in the shoots was only 72 and 31 mg/kg, respectively. The results indicated that B tolerance decreased with increasing salinity of the soil, even though B absorption by plants was 24–62% less in saline than in nonsaline soil at similar B concentrations. As B and salinity often occur together, threshold values of B in soil and plants for optimum growth of wheat will differ with the ECe of the soil. The results suggested that Ca:B ratio in wheat straw is not a reliable indicator of B toxicity in the soil.
Growth of lambs offered fixed amounts of roughage and concentrate either simultaneously or sequentially
Authors: Wilkinson R. G. , Greenhalgh J. F. D. 
Published: March 2009

SUMMARYTwo experiments were carried out in Scotland 1984 to study the efficiency of energy utilization by Suffolk × Blackface lambs. In the first experiment, a digestibility trial, the lambs were fed three diets: roughage (R) consisting of chopped dried grass; concentrate (C) containing 700 g whole barley, 225 g ground barley and 75 g fishmeal/kg dry matter (DM); and a mixed diet (M) containing 500 g of roughage and 500 g of concentrate/kg DM. The DM and organic matter digestibility coefficients of diet M were lower than the ‘expected’ values calculated by summation of the separately determined digestibility coefficients of the component feeds. Similarly, the metabolizable energy (ME) value was 4·0% lower than expected.In the second experiment, 40 lambs ofc. 20 kg live weight (LW) were offered 50 kg roughage DM (ME 9·74 MJ/kg DM) and 50 kg concentrate DM (ME 12·21 MJ/kg DM) either as a mixture (treatment M) or sequentially (treatment S). Lambs on treatment S took 33 days longer to consume their allocation of food than those on treatment M, but achieved a similar final empty body weight and empty body composition. This contrasts with results predicted by a feeding standards model for lambs of a similar LW offered diets of the same ME content. The longer feeding period, and hence greater overall maintenance requirement, of lambs on treatment S was partly offset by associated effects causing a reduction in the total ME available to lambs on treatment M, and partly to improved efficiency of energy utilization for gain and/or a lower daily maintenance requirement of lambs on treatment S. Allowing for associated effects and the adoption of a variable maintenance requirement in current feeding standards would result in a more accurate prediction of animal performance.
On the mathematical description of lactation curves
Authors: Rook A. J. , France J. , Dhanoa M. S. 
Published: March 2009

SUMMARYThe lactation curve may be represented mathematically by the general equationY= Aϕ1(t)ϕ2(t), whereAis a positive scalar, ϕ1,(t) is a positive monotonically increasing function with an asymptote at ϕ1= 1, and ϕ2is a monotonically decreasing function with an initial value of unity and an asymptote at ϕ2= 0. Functions considered as candidates for ϕ1were:(Mitscherlich),(Michaelis-Menten),(generalized saturation kinetic), 1/(1 +b0(logistic), b0exp(Gompertz) and [1+ tanh(b0+ b1t)]/2 (hyperbolic tangent). Candidates for ϕ2were e–ct(exponential) and 1/(1 +ct) (inverse straight line). The 12 models thus obtained andY= Atbe–ct(Wood's model) were fitted to whole-lactation data from 23 animals. Mitscherlich x exponential, Michaelis-Menten x exponential, logistic x exponential, logistic × inverse straight line and Wood's model all fitted well. For these models, expressions for time to peak, maximum yield, total yield over a finite lactation and relative decline at the midway point of the declining phase were obtained. The Mitscherlich x exponential model generally fitted better than Wood's model and, unlike Wood's model, gives simple algebraic formulae for all these summary statistics.
Wheat/chickpea intercropping under late-sown conditions
Authors: Ali M. 
Published: March 2009

SUMMARYField experiments to determine the optimum fertilizer treatment and ratio of wheat to chickpea in late-sown irrigated intercropped populations were done during the winter seasons of 1983–85 on sandy loam soils at the research station of the Directorate of Pulses Research, Kanpur, India. Of the three populations tested (2:2, 2:1 and 3:1 row ratios of wheat: chickpea), the 2:2 row ratio allowed more light interception and transmission to the lower canopy and gave significantly higher yield (4155 kg/ha wheat equivalent) and land equivalent ratio (LER) than the other treatments. Chickpea yields were reduced more than those of wheat under all intercropping systems and the reduction was largest at the 3:1 row ratio. Wheat (cv. Sonalika) was more productive than chickpea (cv. BG261). Application of the normally recommended rate of fertilizer to the wheat only was as effective as applying fertilizers, at the appropriate rates, to both the component crops; indicating that fertilizers applied only to wheat were adequate to meet the requirements of the associated chickpea also.
Combined effects ofAspergillus oryzaefermentation extract and monensin on fermentation in the rumen simulation technique (Rusitec)
Authors: Newbold C. J. , McKain N. , Wallace R. J. 
Published: March 2009

SUMMARYMonensin, an ionophore, andAspergillus oryzaefermentation extract (AO), a fungal feed additive, are growth promoters which modify rumen fermentation. The effects of combining these additives were determined in the rumen simulation technique (Rusitec). Sixteen vessels received 20 g/day of a diet of hay, barley, molasses, fishmeal and a mineral/vitamin mixture (500, 299·5, 100, 91 and 9·5 g/kg DM respectively). AO, monensin (M) and AO + monensin (AO/M) were each added to four vessels at 500, 10 and (500 + 10) mg/day respectively. Both M and AO/M increased propionate (14·5 and 138v.91 mmol/day in controls;P< 0·001) and reduced butyrate production (6·6, 5·2 and 9·1 mmol/day respectively;P< 0·01), whereas AO had no effect. AO increased bacterial numbers by 70% (P< 0·055), while M had no effect, and in the presence of M, AO also had no effect. Proteolytic activity in samples from the vessels decreased (P< 0·05) in all treatments (1·06, 0·71, 0·60 and 0·47 mg14C-casein/mg protein/h for control, AO, M and AO/M respectively). In contrast, deamination of amino acids increased (P< 0·001) with AO and AO/M but decreased slightly with M alone (482, 646, 434 and 644 nmol NH3/mg protein/h). Ammonia output was unchanged (47·4, 57·2, 42·7 and 44·8 mg/day). Thus each additive was dominant over the other for different activities, with monensin generally suppressing the effects of AO rather than vice-versa.