bluuebunny/crossref_metadata_2025 huggingface dataset:
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

Monensin, 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.
Growth and venison production from red deer (Cervus elaphus) grazing red clover (Trifolium pratense) or perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) pasture
Authors: Semiadi G. , Barry T. N. , Wilson P. R. , Hodgson J. , Purchas R. W.
Published: March 2009

A study of growth and venison production from weaner red deer grazing pure tetraploid red clover (RC) or conventional perennial ryegrass/white clover (PRG) pasture was conducted in 1990, with the objective of attaining a minimum slaughter liveweight of 92 kg (50 kg carcass) by 12 months of age in the stags. Ten weaner red deer stags and ten weaner red deer hinds were randomly selected and rotationally grazed on either RC or PRG forage. In autumn and spring, forage allowances were 7 kgDM/hd/day and 8 kgDM/hd/day respectively. In winter, the animals from both groups were grazed together on PRG pasture, at a residual dry matter (DM) of 1100 kgDM/ha. Total nitrogen (N) concentration was higher in RC on offer than in PRG on offer (autumn 3·4v.3·1 %DM; spring 3·8v.3·1 %DM), whilst organic matter digestibility (OMD; autumn 80·5v.76·5%; spring 82·1v.80·3%) was also higher for RC on offer. Diet selected showed similar differences in total N concentration, but there were negligible differences between forages in OMD.

Liveweight gains of RC and PRG stags were respectively 263v.192 g/day, 101v.106 g/day and 354v.341 g/day during autumn, winter and spring, with the corresponding values for hinds being 198. 173 g/day, 52v.53 g/day and 242v.218 g/day. At one year of age, stags grazing RC were 7 kg heavier and hinds 3 kg heavier than animals grazing PRG pasture. Animals grazing RC forage had higher voluntary feed intake (VFI) in both autumn (P< 0·10) and spring (P< 0·001), than animals grazing PRG pasture.

All stags grazing RC forage reached the minimum slaughter liveweight by one year of age, compared to 75% of those grazing PRG pasture. At slaughter, stags that had grazed RC produced heavier carcass weights (59·9v.54·5 kg,P< 0·01), had higher carcass dressing percentage (55·3v.53·2 %;P< 0·01), and tended to have slightly greater carcass subcutaneous fat depth than stags grazing PRG pasture, but this effect disappeared when the data were corrected to equal carcass weight. All stags grazing RC produced velvet antler, relative to 75% of those grazing PRG; in stags producing harvestable velvet antler, there was no difference in antler weight between those grazing RC and PRG. It is concluded that RC offers potential as a special-purpose forage for the growth of weaner red deer.
Leaf area and transpiration efficiency during different growth stages in oats
Authors: Ehlers W.
Published: March 2009

Dry matter production, transpiration and transpiration efficiency (DM production: transpiration) were studied during vegetative growth of oats over 4 years (1976–77 and 1982–83) in field experiments on loess-derived soils near Gottingen, Germany, under different weather conditions. Shoot and root dry matter and leaf area were measured or estimated regularly during the season. The rate of evapotranspiration including intercepted rain water by leaves (ET) was determined during five consecutive growth stages from the water balance in the 2 m soil profile. The rate of soil evaporation (E) and the rate at which rain water was intercepted by leaves (I) were estimated separately in order to attain T, the transpiration rate (T = ET–E–I), or IT, the rate of interception of rain water by leaves plus transpiration (IT = ET–E). The potential evapotranspiration rate (ETp) was derived from meteorological parameters.

During the early stages of oat development (seedling growth and tillering), T and IT, related to ETp, were higher than expected from crop growth rate (CGR), calculated for shoot and total dry matter including roots, respectively. It was concluded that, at a leaf area index (LAI) of < 3·4, part of the solar radiation was converted to sensible heat between plant rows, increasing ETp near the ground and hence T, but not CGR. Because of this, LAI influenced IT efficiency and the crop-specific constant m of de Wit's formula. IT efficiency was not only dependent on LAI but also on ETp. Grain yield was related to both cumulative IT (ITC), normalized by ET, and leaf area duration during the period from anthesis to harvest. Increased leaf area duration after anthesis may partly explain the higher yields obtained with modern high-yielding varieties of small-grained cereals.
Integrated management of straw and urea nitrogen in lowland rice under a rice-wheat rotation
Authors: Mahapatra B. S. , Sharma G. L. , Singh Nayab
Published: March 2009

The average yields of a 3-year field experiment (1985/86–1987/88) on a mollisol at Pantnagar showed that, at 87 kg N/ha, applying urea supergranules (USG) gave 0·47 t/ha more rice grain than split application of prilled urea (PU). The data also showed that, at this rate of N, one-third (29 kg N/ha) of inorganic N can be substituted by fresh straw (wheat or rice) applied at planting to give similar rice yields. However, at a total of 58 kg N/ha, 29 kg N/ha applied as straw with 29 kg N/ha of PU or USG reduced yield compared with 58 kg N/ha of PU or USG alone, except in 1986/87. Yield differences were attributed to differences in number of panicles/m2, N uptake by the crop and mean wet soil NH4+-N obtained at various stages of crop growth during 1986/87 and 1987/88. Wheat grown after rice in 1985/86 and 1986/87 showed significant residual effects in plots with straw application and these were correlated with the rate of hydrolysable organic N (HN) obtained after rice.
Nodal structure and branching ofTrifolium repensin pastures under intensive grazing by sheep
Authors: Hay M. J. M. , Newton P. C. D. , Thomas V. J.
Published: March 2009

The nodal structure of white clover plants was studied in New Zealand in pastures stocked at 22·5 ewes plus lambs/ha and either continuously or rotationally grazed. Intact plants were sampled every month for a year (1988/89) by removing turves and washing out the plants. Plants were classified according to the degree of branching as first (unbranched, single-stolon plants), second, third or fourth order (plants with at least one quaternary branch). Where possible from each turf, four plants of each of the four branching orders were sampled and, for each stolon of each plant, nodes were ascribed positions numbered from the stolon apex, and the position of nodes with a live branch and the total number of nodes/stolon were recorded.

The mean number (and 5 and 95% quantiles) of nodes/plant was 15·7±0·26 (9, 24) for the firstorder, 42·2±0·90 (18, 81) for the second-, 91–4±2–13 (37, 163) for the third- and 163·7±7·49 (63, 367) for the fourth-order plants. Grazing management and month of sampling had minor effects on these values. The mean number of nodes/stolon within branched plants depended on the category of the stolon within a plant, the presence or absence of an apex and on the branching order of the plant. The first 10,.15, 20 and 25 node positions accounted for, respectively, 64, 79, 90 and 95% of total nodes in the field population and 39, 62, 79 and 90% of all branches. Successful branch initiation occurred at recently formed nodes at positions 3–10, emphasizing the significant contribution of such nodes in growth and persistence of white clover in grazed swards.

Where grazing management allows little consumption of stolon and there is adequate moisture, growth and fragmentation maintain the mean node composition of the branching orders reasonably constant throughout the year. Thus, any seasonal variation in the overall mean number of nodes/plant in a population must be driven by seasonal changes in the distribution of plants among the branching orders. However, there was evidence of mean number of nodes/plant decreasing in the third and fourth orders after dry conditions.
Comparison of boom and airblast sprayers on T-trellis apples
Authors: Hogmire H. W. , Diener R. G. , Crim V. L.
Published: March 2009

T-trellis apple trees treated with combinations of fungicides and insecticides applied with a boom sprayer had a lower percentage of fruit damage from diseases and insects than those treated with an airblast sprayer. With the boom sprayer, chemical deposit was uniform in distribution between outer and inner parts of the tree canopy, but with the airblast sprayer there was more than a threefold difference in deposit between parts of the canopy. The boom sprayer was inferior to the airblast sprayer in the control of apple aphids (Aphis pomi) when vertical top growth (watersprouts) had grown to 0·7–1 m. Management of aphids with a boom sprayer would probably require the control or periodic removal of watersprout growth, or the use of systemic insecticides.
Effect of feedingLeucaena leucocephalaas the sole ration on nutrient utilization and body weight in goats
Authors: Girdhar N. , Lall D. , Pathak N. N.
Published: March 2009

In an experiment conducted in the sheds of the Animal Nutrition Division of the Indian Veterinary Research Institute in 1988/89, eight adult Black Bengal goats were divided into two groups of four animals each. Animals in the control group were offered a conventional diet (concentrate and available roughage as per National Research Council standards) and those in the experimental group were fed exclusively on fresh leucaena foliage (young and newly developed leaves and shoots) for 300 days. Dry matter intake (DMI) and body weight of animals in the experimental group decreased in the first 6 weeks; daily DMI/lOOkg body weight was 306 ± 0·34kg in the control group and 2·40 ± 0·18 kg in the experimental group.

There were significant differences in the apparent digestibilities of crude protein and nitrogen-free extractives; contents of digestible crude protein (DCP) and total digestible nutrients were 5·2 and 20·3%, respectively, in the controls and 65·6 and 59·1 %, respectively, in the experimental group. DCP intake was significantly higher in the experimental group as a result of high protein content in foliage but it was not well utilized.

In the control and experimental groups, respectively, daily mean retention of nitrogen was 2·01±0·14 and 1·54±0·12 g/day, of calcium 1·60±0·08 and 2·92±1·69 g/day, and of phosphorus 1·12±0·25 and 0·24±0·07 g/day, the phosphorus balance being significantly lower in the experimental group. Blood calcium and serum glutamate oxaloacetate transaminase/serum glutamate pyruvate transaminase concentrations were statistically similar in both groups but the concentration of inorganic P was significantly lower in the blood of animals fed leucaena.
Effects of plant population density on determinate and indeterminate forms of winter field beans (Vicia faba) 2. Growth and development
Authors: Pilbeam C. J. , Hebblethwaite P. D. , Nyongesa T. E. , Ricketts H. E.
Published: March 2009

In studies at the University of Nottingham at Sutton Bonington in two consecutive seasons beginning in 1986/87, Bourdon, an indeterminate cultivar, and 858, a determinate selection (provided by Plant Breeding International, Cambridge), were compared under six target plant population densities ranging from 10 to 80 plants/m2.

As the season progressed, total dry matter production increased to a maximum and then declined. However, growth rates slowed at pod set because, it is suggested, of the change in the chemical composition of the newly synthesized biomass, from carbohydrate to protein, at that time. Leaf area duration was greater in Bourdon than in 858, especially during pod set, but it bore no relation to seed yield. Specific leaf area was unaffected by competition for light. It is proposed that changes in plant population density affect the competition for assimilates within a plant rather than the competition for light between different plants. Losses of branches and reproductive nodes, with time, are cited as evidence for this. The apparent causes of the lower yield of determinate forms of winter field bean relative to indeterminate forms are discussed.
Light interception and utilization in determinate and indeterminate cultivars ofVicia fabaunder contrasting plant distributions and population densities
Authors: Stützel H. , Aufhammer W.
Published: March 2009

In a 2-year field experiment at Hohenheim in 1987–88, with an intact or partly deflowered indeterminate cultivar and a determinate cultivar, light interception and dry matter production were highest in crops grown in isometric stands (equal distances between plants), lowest in double rows and intermediate in single rows. Dry matter production was greater at high than at low population density and in the wetter and cooler weather of 1987. Population density had a greater effect on DM production than on light interception. The greater leaf canopies under high density and in 1987 (Stützel & Aufhammer 1991) reduced light extinction coefficients. In the determinate cultivar, light extinction coefficients were consistently higher and light use efficiencies were consistently lower than in the indeterminate cultivar. Deflowering the indeterminate genotype and different planting designs did not change light use efficiencies and light extinction coefficients. In general, differences in light use efficiencies were inversely related to differences in light extinction coefficients.
Growing spring cereals in a white clover (Trifolium repens) crop
Authors: Williams E. D. , Hayes M. J.
Published: March 2009

Spring barley and spring oats were strip-seeded into crops of the white clover cultivar Alice at Hereford in 1987 and cultivar S184 at Aberystwyth in 1988. Drilling was done with or without a band-spray of glyphosate, a moderate or low (1988 only) dose of paraquat or into plots where the clover had been killed by herbicide 2 months previously.

In the first experiment, initial cereal emergence was sparse; growth was suppressed in the unchecked (unsprayed) clover base but was vigorous in the clover-free plots; the cereals also became dominant in the swards sprayed with herbicide. Whole-crop yields in mid-August were 13, 3–4 and 8–10 t DM/ha in the plots in which clover was killed, unchecked or checked with herbicide. Clover contributed 4–12% of the harvested herbage in the latter treatment. This treatment also yieldedc. 70 % as much N, carbohydrate and fibre as that without clover. Grain yields exceeded 7 t/ha without clover but were only 0·3 t/ha for barley and 1·1 t/ha for oats with unchecked clover; in the checked clover plots, barley yielded 60% and oats 78% as much as on the clover-free plots. Four and 5 weeks after whole-crop harvest, residual clover growth was 27 and 39% of that on unchecked plots for oats and barley, respectively.

In the second experiment, the cereals emerged thickly but were later dominated by the clover, and an equitable balance was achieved only with the larger dose of paraquat. However, the oat cultivar Emrys was suppressed less than the tall barley cultivar Dandy; the short barley cultivar Digger was the most suppressed. Mean whole-crop yields were 11 t/ha in the treatment without clover, about half this in the unchecked bases andc. 9 t/ha with the larger dose of paraquat. Differences in chemical composition reflected much larger clover contents in 1988 than in 1987. Yields of N and water-soluble carbohydrate were at least as large or larger with moderate paraquat than for the clover-free plots. Grain yields ranged from 5·6 to 6·9 t/ha for the three cereal cultivars without clover but were negligible to very small in the unchecked and band-sprayed treatments, and were 3·4 and 2·0 t/ha for oats and barley, respectively, with the larger dose of paraquat. Residual stolon weights, 70–80 days after whole-crop harvest, greatly exceeded initial values in all treatments. They were smallest following the larger dose of paraquat, and larger in Digger than in Dandy, which in turn was larger than in Emrys.

It is concluded that the concept of growing cereals in a clover base shows potential as a low input–moderate output system of cereal production. However, further longer term work is needed on regulation of the cereal–clover balance, on the release and uptake of N and the environmental effects of the technique.
A note on the measurement of heat exchange by radiotelemetry in black desert goats during winter
Authors: Goyal S. P. , Ghosh P. K.
Published: March 2009

Recently, radiotelemetry has been widely used in the measurements of various physiological attributes, e.g. body and skin temperatures, heart rate and heat flux across the surface in unrestrained animals (Zervanos & Hadley, 1973; Moen, 1978; Mautz & Fair, 1980). The present note provides some basic information on heat flux across the skin in untethered black Marwari goats of the Rajasthan desert, measured by radiotelemetry during winter.
Cultivatino practice, sowing season and soil erosion on the South Downs, England: a preliminary study
Authors: Robinson D. A. , Boardman J.
Published: March 2009

Seven plots were laid out for the 1985–6 growing season on the Chalk Downs near Lewes, East Sussex, to study the relationship between cultivation practice, soil conditions and erosion rates. Three plots were sown with cereals in autumn and three in spring. The seventh plot was ploughed and kept bare. In both spring and autumn, one plot was conventionally cultivated by ploughing and harrowing, one was direct drilled through burnt stubble and the third was direct drilled through the debris of the previous year's straw and stubble. Erosion was greatest from the conventionally cultivated plots and least from those direct drilled through unburnt stubble. Monitoring of moisture, infiltration, strength and compaction properties of soils suggests that from late autumn onwards soil conditions on the plots were very similar and the major factor determining the different erosion losses from the plots was the percentage vegetal cover (crop, weeds and residues). The results suggest that direct drilling through unburnt stubble may be a way of obtaining high yields with low erosion risk on the Downs, but the long-term consequences of such a practice remain unknown.
An analysis of morphological development stages in avalon winter wheat crops with different sowing dates and at ten sites in England and Scotland
Authors: Porter J. R. , Kirby E. J. M. , Day W. , Adam Jill S , Appleyard Margaret , Ayling Sarah , Baker C. K. , Beale P. , Belford R. K. , Biscoe P. V. , Chapman Anne , Fuller M. P. , Hampson Janice , Hay R. K. M. , Hough M. N. , Matthews S. , Thompson W. J. , Weir A. H. , Willington V. B. Anne , Wood D. W.
Published: March 2009

An experiment to measure the variation in the phenological and apical development ofwinter wheat (cv. Avalon) in England and Scotland is described. Ten sites which ranged from Aberdeen (57·2° N), the most northerly, to Newton Abbot (50·6° N), the most southerly, were included in the survey, and at each site seed was hand-sown in mid-September, October and November 1983. Developmental stages and sampling procedures were precisely defined to ensure uniformity in scoring by the observers at each site. Temperatures during the growing season were in line with the long-term means, though spring was cooler at all sites and summer warmer at most. The range of monthly-mean temperatures between sites was about the same as the difference between consecutive months. The method of analysis of development rates and durations was in terms of thermal time, modified by sensitivity to photoperiod and a vernalization requirement that slowed early development until a number of days of low temperatures had been experienced. In general, crops at northern sites developed more slowly than those in the south and particularly the south-west of England. There was less variation in the timing of apical stages for later sowings. Developmental rates responded linearly to temperature and photoperiod, with the base temperature increasing for later phases of development. The effect of photoperiod in modifying the rate of development was apparent for all developmental phases from emergence to anthesis, longer days accelerating development, but there was no effect on the duration of the grain-filling period. Vernalization exerted its effect solely within the phase from emergence to double ridge, and had a major influence on the variation between sites only for the first sowing.
The effect of sheep urine on clover performance in a grazed upland sward
Authors: Marriott Carol A. , Smith Morag A. , Baird M. A.
Published: March 2009

The effect of artificially applied urine on clover performance in a perennial ryegrasswhite clover sward grazed by sheep was examined during summer. Sheep urine or deionized water (51/m2) was applied to areas (2·70 × 1·25 m) which were protected from subsequent excretal return by graze-through cages. Grass and clover populations, nitrogen-fixing activity, soil nitrogen and soil pH were monitored over the following 90-day period.

Urine reduced clover population density, stolon length and dry weight but had little effect on number of grass tillers. Nitrogen-fixing activity of clover was reduced initially to less than 30% of control values, perhaps owing to high levels of soil inorganic nitrogen inhibiting fixation, although osmotic effects due to the high salt concentration in urine cannot be discounted. The lower levels of activity at later dates were due largely to reduced clover in urine-treated areas. Soil pH (0–5 cm) was increased by about 0–5 units 3 days after urine application, with a smaller increase in the 5–10 cm horizon. Recovery of urine nitrogen in the soil mineral N pool was at best 27% of the added nitrogen.

The results are discussed in terms of the significance of urine-affected areas in determining a patchy distribution of clover in grazed swards; the role of animals in the transfer of fixed N from clover to grass is considered.
Reproductive performance of sheep and goats under native husbandry
Authors: Esievo K. A. N. , Eduvie L. O. , Fasanya O. O. A.
Published: March 2009

Although over 90% of small ruminant production in Nigeria is done under native husbandry or semiintensive management, relatively little information on their reproductive performance is available. However, information on the reproductive performance of Nigerian small ruminants under intensive management conducted at Research Centres or Institutes is readily available (Adu, Buvanendran & Lakpini, 1979; Adu, Brinckman & Kuteyi, 1979; Molokwu & Umunna, 1980; Osinowo & Ekpe, 1985). Such reproductive information includes age at first lambing or kidding, birth weight, lambing or kidding intervals, seasonal effects and conception rates. Although the latter findings are meant for dissemination through Extension Services to rural producers for application, records of the effects of such application are scanty.
Associations amongFusariumwilt resistance, flower colour and number of flowers per fruiting node in chickpeas (Cicer arietinumL.)
Authors: Singh Harjit , Kumar J. , Smithson J. B. , Haware M. P.
Published: March 2009

Corolla colour in chickpea (Cicer arietinumL.) is white or various shades of pink or blue (Smithson, Thompson & Summerfield, 1985). Normally, a leaf axil subtends a single peduncle bearing a single flower but ‘double-flowered’ types, where a pro-portion of the peduncles subtends two flowers, are not uncommon and produce 6–11 % more seed yield than the normal single-flowered type (Sheldrake, Saxena & Krishnamurthy, 1978)
Effect of harvest methods on the second flush yield of short-duration pigeonpea (Cajanus cajari)
Authors: Chauhan Y. S. , Sheldrake A. R. , Venkataratnam N.
Published: March 2009

Short-duration pigeonpea can give up to three harvests in environments with mild winters (e.g. minimum temperature above 10 °C) such as those prevailing in peninsular India (Sharma, Saxena & Green. 1978; Chauhan, Venkataratnam & Sheldrake, 1984). This is mainly due to the short time (about 120 days) taken to produce the first flush, and the strong perennial character of pigeonpea. The seed yield of short-duration pigeonpea in this multiple-harvest system may reach 5·2 t/ha (Chauhan et al. 1984).
Factors affecting the efficiency of urea for pot-grown ryegrass
Authors: Watson Catherine J.
Published: March 2009

Urea can be an inefficient nitrogen source, compared with ammonium nitrate, on calcareous soils (Ernst & Massey, 1960) and under dry conditions (Murphy, 1978) as a result of ammonia volatilization. However, the interaction between factors which can affect the performance of urea is not clearly understood. The risk of ammonia volatilization would appear to be higher on light soils with a low cation exchange capacity than on heavier soils (Fenn & Hossner, 1985). Field trials in the Netherlands indicated that a minimum of 5 mm of rain must fall within 2 days of application to give good dry-matter yields with urea (Van Burg, Dilz & Prins, 1982). In addition ammonia volatilization has been affected by initial soil moisture content in some studies (Fenn & Escarzaga, 1977) but not in others (Gasser, 1964).
Effect of conceptus growth on the contents of the maternal gastrointestinal tract in ewes fed at a constant rate throughout gestation
Authors: Faichney G. J. , White G. A. , Donnelly J. B.
Published: March 2009

Multiparous Corriedale ewes were maintained on a constant feed intake such that the body weight (i.e. live weight less gravid uterus) of single-bearing ewes at the end of gestation approximated their live weight at mating. The ewes were allocated to one of five groups, designated for slaughter at 0, 50, 90, 120 and 140 days of gestation. At slaughter, the gravid uterus was removed, weighed and its components dissected out and the contents of all sections of the gastro-intestinal tract were removed, weighed and sampled.

Foetal growth was described by a Gompertz model. It was predicted that, at day 150, a twin foetus would have been 0·95 of the weight of a single foetus but this difference was not statistically significant. The foetal proportion of the gravid uterus followed a sigmoid curve during gestation to reach a predicted value of 0·60 at day 150. Predicted birth weights represented 10·4 and 18·6% of maternal body weight in single- and twin-bearing ewes.

The digesta content of the rumen and of the whole gastro-intestinal tract was not significantly affected by gestation. However, there was a tendency for the values to decline to day 90, then increase during the last third of gestation. It was suggested that the decline was due to hormonal rather than direct physical effects. By contrast, the amounts of organic digesta constituents in the rumen descreased as gestation progressed (P < 0·01) indicating an effect of gestation on rumen propulsive activity.
Root formation in cuttings ofDioscorea composita
Authors: Viana Ana Maria , Felippe G. M.
Published: March 2009

The tubersof Dioscorea compositaHemsl. contain a high level of diosgenin, and hence there is economic interest in this plant. Levels of diosgenin vary greatly in different clones of the species. Vegetative propagation was studied with a view to obtaining plants with high levels of diosgenin. In this study cuttings from 1-year-old vegetative plants were used for propagation. The cuttings were treated with a single application of indole-3-butyric acid (IBA) and several applications of 6 benzyladenine (6-BA). Rooting was never observed in untreated cuttings. Cuttings treated with IBA produced callus and roots. Early application of 6-BA delayed senescence but inhibited callus and root formation. New plants were obtained with one application of IBA followed by applications of 6-BA at 48 h intervals initiated 2 weeks after IBA application. In some experiments, all cuttings treated this way produced new plants.
Statistical equations for estimating field capacity, wilting point and available water capacity of soils from their saturation percentage
Authors: Dahiya I. S. , Dahiya D. J. , Kuhad M. S. , Karwasra S. P. S.
Published: March 2009

Statistical equations were derived for estimating three soil moisture constants, i.e. field capacity (FC), wilting point (WP) and available water capacity (AWC), from soil saturation percentage (SP), which is an easily determinable parameter. The regression equations were evaluated from a data set obtained on 438 soil samples collected from different horizons of 111 profiles of the Indogangetic Plains in northern India, having a wide variation of texture and other physico-chemical properties. The three soil moisture constants were positively correlated with logarithms of SP (r = 0·985 for FC v. In SP, 0·979 for WP v. In SP, and 0·914 for AWC v. In SP). The regression equations were thetested on an independent set of experimental data on 57 samples collected from 14 representative soil profiles of the study area. Values of the three moisture constants of this data set, predicted from the regression equations, were in exceptionally good agreement with the observed values. The mean estimation error (the error of the estimated value relative to the measured value) was only 0·55% for FC, 0·12% for WP and 0·67% for AWC.
Effect of spacing and row orientation on the growth and nitrogen fixation of Azolla and their effects on rice
Authors: Singh A. L. , Singh P. K. , Singh P. L.
Published: March 2009

The intercropping of Azolla pinnata (Vietnam) with rice varieties transplanted in rectangular (40×10 cm) and double-narrow-row (15 × 10:65–80 cm) spacings showed faster growth and nitrogen fixation than in square (20 × 20 cm) spacing with the same number of hills per unit area. Inoculation of 2·0 t/ha fresh Azolla, 10 and 30 days after transplanting, produced Azolla mats on the water surface 25 and 50 days after transplanting, respectively. The total fresh biomass of Azolla grown with different rice varieties in square spacing was 26·7–33·0 t/ha; this produced 41·9–61·3 kg N/ha. However, rectangular and double-narrow-row spacing produced 28·7–37·7 and 34·4–39·6 t/ha fresh Azolla containing 53·9–69·0 and 58·0·73–3 kg N/ha, respectively if the rice rows were transplanted in north-south direction and 36·3–41·5 and 40·0–43·7 t/ha fresh biomass containing 63·4–74·2 and 65·3–83·3 kg N/ha, respectively in east-west direction.

The grain and straw yields of rice grown in rectangular and double-narrow-row spacing with north-south row orientation were lower than the yields of rice in square spacing, but the east-west row orientation of these spacings showed yields similar to those obtained by growing rice in square spacing.
Bone growth in the indigenous Nigerian pigs as a function of age, sex and body weight
Authors: Essien A. I. , Fetuga B. L.
Published: March 2009

The left half carcasses of 64 female, 64 castrated male and 64 intact male indigenous Nigerian pigs were dissected in order to study the bone growth between birth and 672 days of age. Total bone weight as well as the weights and lengths of femur, tibia–fibula, humerus and radius–ulna were studied at 16 ages. While bone weights increased between 34 and 45 times from birth to the terminal age range, bone lengths on the average only quadrupled within the same period. Maximum growth in bone weight occurred at 112 days of age whereas bone length attained maximum growth rate at 56 days of age when the body weights had averaged 15·8 and 6·2 kg respectively.

Beyond these body weights, the growth rates declined. Although sex differences for total bone weight were not significant, the individual long bones studied exhibited significant sex differences. Highly significant age and sex influences were obtained for the relative bone weights.

The growth coefficientsbdetermined for the individual bones and total bone using the logarithmically transformed allometric equationY=oXb, ranged from an average of 0·76 for radius–ulna to O·80 for femur. Pooled values for total carcass bone was 0·84. The values agreed with those reported in literature with side weight as independent variable, and confirm bone to be early developing. Bone lengths were related more to body weight than to chronological age as judged by theR2values. In all the bone traits studied, intact male pigs showed larger values than the castrated male and female pigs.
Muscle growth and development in the indigenous Nigerian pigs as influenced by age, sex and body weight
Authors: Essien A. I. , Fetuga B. L.
Published: March 2009

Muscle growth was studied for 64 female, 64 castrated male and 64 intact male indigenous Nigerian pigs at 16 ages between birth and 672 days of age. Highly significant (P< 0·001) age differences were obtained for the proportion of total muscle, each muscle group and the 13 individually dissected (seven hind limb, two spinal column and four fore limb) muscles. Sex differences were significant (P< 0·05) for the proportion of total muscle and some of the individually dissected muscles.

A highly significant (P< 0·01) increase in the rate of muscle deposition for each muscle group occurred between 56 and 112 days. Muscle deposition continued at the same rate up till 224 days of age before the peak was attained between 280 and 392 days when the average body weight was between 40·8 and 61·2 kg. A continuously significant (P< 0·05) decline in the rate of muscle deposition was obtained beyond 392 days of age. Growth coefficientsbcalculated from the linearly transformed allometric equation Y = aXbwere generally higher in the early phase of growth (0–168 days) than in later phases considered. However, growth coefficients obtained for the whole period revealed that apart from M. gastrocnemius, the other hind limb and spinal column muscles exhibited either ‘high’ or ‘average’ growth impetus. The fore limb muscles had growth coefficients significantly (P< 0·05) less than 1·00 and were therefore classified as having ‘low’ growth impetus. Generally, the intact male pigs showed superiority to the female and castrated male pigs in muscle growth and development.
Field measurements of the photosynthetic rate of potatoes grown with different amounts of nitrogen fertilizer
Authors: Firman D. M. , Allen E. J.
Published: March 2009

Three experiments are reported in which the photosynthetic rates of potatoes grown with various amounts of applied nitrogen (N) fertilizer were measured. Rates of photosynthesis in leaves of plants grown without applied N reached levels as high as those receiving N in all experiments. The rate of photosynthesis in the uppermost leaves of the variety Pentland Crown was found to increase during the season, whereas in Estima rates remained the same. Decline in the rate of photosynthesis with leaf age was more rapid in strongly shaded leaves than in less shaded leaves which were found to be photosynthetically active 8 weeks after expansion.
Efficiency of utilization of energy for egg production in feed-restricted single comb White Leghorn hens
Authors: Degen A. A. , Kam M. , Rosenstrauch A.
Published: March 2009

Egg production and body mass changes were measured in six groups, each containing 10 single comb White Leghorn (SCWL) hens, in which each group received decreasing amounts of dry matter (D.M.) in decrements of 10%. Group 1 received 101·2 g D.M./day (100%), an amount normally offered these hens, whereas group 6 received 52·8 g D.M./day (50%). Egg production remained relatively high but body mass declined rapidly in the feed-restricted groups when compared with group 1 in the first 4 weeks (period I); in the second 4 weeks (period II), egg production declined to a great extent but body mass remained constant. Egg production and egg mass were significantly lower in period II than in period I in the feed-restricted birds. In period I egg production did not decrease significantly until the hens were restricted in feed by 30%; in period II this occurred at 20% feed restriction. Energy of eggs produced as a fraction of metabolizable energy intake (MEI) tended to increase in the feed-restricted groups when compared with group I in period I, but decreased significantly at the 40% and 50% group in period II. Maintenance energy requirements for the hens were 569·2 kJ/kg0·75per day and the efficiency of utilization of energy for egg production was 88·2% in period I; these values were 551·6 kJ/kg0·75per day and 74·0%, respectively, in period II. Energy yielded from the catabolism of body tissue per gram body mass loss was 23·08 kJ.

It was concluded that the hens initially maintained near-normal egg production at the expense of body energy reserves and then at the expense of egg mass. The efficiency of utilization of energy for egg production was higher when the energy source was mainly from body energy reserves than from MEI (88·2% v. 74·0%). The level of feed restriction and its length of imposition, the body energy reserves of the hen and the source of energy for egg production can explain many of the different responses reported in feed-restricted laying hens. In addition, reduction of 20 to 30 % feed intake in laying hens had little effect on egg production for a short period (4 weeks) during which time the hens mobilized body energy reserves. If these hens were to be sold, then this would add an additional option to this enterprise; that is, reduce feed cost at the expense of body mass prior to the sale of the hens.
Some indices of the carcass composition of Dorset Horn Top Cross lambs. II. Specific gravity as an index of the fat content of the carcass and of various joints
Authors: Khandekar V. N. , McManus W. R. , Goldstone C. L.
Published: March 2009

An experiment was conducted to investigate the relationship between specific gravity and total fat content of the half-carcass. Specific gravity was found to be highly but negatively correlated with the percentage of fat in the half-carcass

(r = −0·9841, P < 0·001).

It was also found that the sample joint is a satisfactory index of fatness of joint as well as that of the half-carcass.
Growth curve analysis for treatments-by-environments interaction effects
Authors: Edmondson R. N.
Published: March 2009

Growth curves fitted to factorial data can be modelled using an extrinsic time variate or using the mean responses within the levels of a subset of factors. Where factors can be partitioned into a set of ‘treatment’ factors and a set of ‘environment’ factors, fitting growth curves to the mean effects of environments allows the effects of treatments to be assessed relative to a uniform background growth rate. This leads to a test of a null hypothesis of equal treatment effects in all environments, given that the mean growth rate and stage of development in all environments is equal. The approach is exemplified using data from a glasshouse tomato crop experiment testing variety, nutrient and sowing date factors. Variety and nutrient treatment effects were of direct interest but sowing dates were intended to generalize results by providing a range of growing environments. Treatment effects are analysed by modelling running cumulative yield totals by growth curves and regressing variety and nutrient growth variates on the mean growth variate within each sowing date. In the discussion the case of more than one environmental factor is considered.
The effect of seed rate and nitrogen fertilizer on the yield and nutritive value of oat-vetch mixtures
Authors: Moreira N.
Published: March 2009

Experiments were conducted on the seed rates of the components of oat-vetch mixtures combined with varying rates of nitrogen fertilizer in a rainfed area of north-east Portugal in 1982–3 and 1984–5.

Forage oats grown alone showed a very high yield response to N and rainfall ranging from 30 to 18·2 t D.M./ha, but had a very low crude protein concentration (37–54 g/kg D.M.) and a poor mineral nutrient composition.

The increased use of vetch in the seed mixture had a buffering effect on dry-matter (D.M.) yield but this depended very much on crop N nutrition. For N-deficient conditions vetch inclusion increased the D.M. yield and had a strong positive effect on total forage crude protein (CP) and mineral composition. When crop N nutrition was good, very high D.M. yields (> 12 t D.M./ha) were possible using a high proportion of oats, with vetch making a reduced contribution to the yield and nutritive value of total forage.

Seed rates suggested in the literature for Mediterranean conditions are adequate for low N inputs and low available soil N, but not for high D.M. yields which can only be obtained by using a higher proportion of oats and adequate N fertilizer.
Row-and-column designs with two replicates
Authors: Patterson H. D. , Robinson Dorothy L.
Published: March 2009

This paper presents a series of 20 two-replicate row-and-column designs for field trials comparing between 25 and 100 varieties on small plots.
A comparison of three laboratory techniques for the estimation of the digestibility of feedstuffs for ruminants
Authors: Omed H. M. , Axford R. F. E. , Chamberlain A. G. , Givens D. I.
Published: March 2009

Three in vitro methods, one enzymic and two microbial, were applied satisfactorily to the determination of the dry matter digestibility of forages, but failed when applied to a variety of concentrate feeds. The microbial methods had the advantage that the proportion of weight lost from forages during the in vitro process approximated closely with their determined in vivo digestibilities.

The microbial method based on sheep faeces was as effective as that using rumen liquor in digesting ruminant feedstuff's in vitro. Since sheep faeces are readily obtained from intact animals, the faeces liquor method would seem to have a distinct advantage in use.
Storage-root weight, diameter and length relationships in carrot (Daucus carota) and red beet (Beta vulgaris)
Authors: Benjamin L. R. , Sutherland R. A.
Published: March 2009

The functional relationships between logediameter and logeweight, and between length and diameter of the storage roots in carrot and red beet were described by two linear equations. These equations were fitted to data from three red beet and two carrot experiments. The agreement between the fitted and observed data was close. With increasing plant population density of red beet, the slope of the relationship between length and diameter decreased and the intercept increased. Although these changes in slope and intercept were statistically significant (P< 0·05), their magnitude was of negligible practical importance. The relationship between logediameter and logeweight was little affected by length; the relationship between length and diameter was little affected by logeweight.

Using these equations in independent experiments, the diameters of roots of both species were predicted from measured root weights. The roots were then assigned to various commercial diameter grades on the basis of either the measured or the predicted diameter. Except for a few roots of red beet greater than 85 mm in diameter, there was close agreement between the observed and predicted number of roots in each grade.

Any model which predicts root weight might be extended to predict yield of marketable size grades, using these equations as a calibration between weight, diameter and length.
Nitrogen balance studies in rice using 15N-labelled urea and urea supergranules
Authors: Mohanty S. K. , Chakravorti S. P. , Bhadrachalam A.
Published: March 2009

Recovery of applied nitrogen by the rice crop is invariably low, often 30–50% (Prasad & De Datta 1979). The poor recovery has been attributed to different types of losses occurring in the rice field. Recovery improved with split application, delayed application or deep placement (Pillai & Vamadevan 1978; Craswell & Vlek 1979), indicating that the management factor plays an important role in increasing fertilizer nitrogen efficiency. To investigate such factors, and seasonal effects, field experimentswere carried out using 15N-labelled urea (PU) and urea supergranules (USG). The recovery of fertilizer 15N by the plant and retention in the soil were studied in both dry and wet seasons.
Intraspecific variation for frost hardiness in white clover
Authors: Caradus J. R. , Mackay Allison C. , Bosch J. Van Den , Greer D. H. , Wewala G. Sirimathie
Published: March 2009

The frost hardiness of 5-month-old seedlings of 12 white clover cultivars was examined at – 4, – 8, – 12 and – 16°C and in a subsequent study the frost hardiness of 6-month-old seedlings of 190 experimental lines and 23 cultivars and ecotypes was determined at – 12°C. There were large differences among cultivars and lines in frost tolerance based on the percentage of plants damaged and the percentage of leaves killed. The most frost-hardy were the cultivars Podkowa and Undrom and ecotypes collected from Kaikoura and Nelson Lakes. There was no significant, correlation between the percentage germination of cultivars at 4 °C and their subsequent frost hardiness.

Large-leaved, erect cultivars tended to be more frost sensitive than small-leaved, prostrate cultivars. Frost-tolerant cultivars and lines tended to be acyanogenic. Selection for low winter growth did not increase frost tolerance. However, lines derived from crosses between genotypes of cold-hardy lines selected for rapid germination at 4 °C were more frost-hardy than lines from genotypes selected in a similar way that had been crossed with unselected Huia genotypes.
Ammonia volatilization from rice fields in alkaline soil as influenced by soil moisture and nitrogen
Authors: Singandhupe R. B. , Rajput R. K.
Published: March 2009

Volatilization of ammonia from urea applied to rice on a soil of pH 9·3 was measured during 1982 and 1983 at Karnal. For three moisture regimes (continuous submergence, and irrigation 1 day and 4 days following subsidence of ponded water) mean ammonia losses varied from 28·2 to 31·8 kg N/ha. For urea applications between 40 and 120 kg N/ha, mean ammonia losses varied from 26.1 to 33.7 kg N/ha. Ammonia losses were highest on the second day following urea application and dropped to near zero 7–8 days after application.
The effects of advancing season on the chemical composition of marrow stem kale
Authors: Jones D. J. C.
Published: March 2009

1. Four varieties of marrow stem kale in the first season, and thirteen in the second, were sampled on three occasions during the first half of the winter. Intervals between samplings were up to 1 month. The plants in the samples were divided into leaf, top half of the stem, and bottom half. The levels of dry matter, proximate constituents and minerals were determined in each sample.

2. The differences in composition between the three main fractions of the plant were highly significant for all the chemical constituents, except magnesium. The values for the chemical constituents in the top half of the stem were intermediate between those of the leaf and the bottom half of the stem for most constituents; it had the lowest values for dry matter and the highest for potassium and phosphorus. The distribution of chemical constituents between the whole stem and the leaf were similar to those reported previously.