bluuebunny/crossref_metadata_2025 huggingface dataset:
A new dual-purpose ultrahigh vacuum infrared spectroscopy apparatus optimized for grazing-incidence reflection as well as for transmission geometries
Authors: Wang Y. , Glenz A. , Muhler M. , Wöll Ch.
Published: November 2009

A newly designed ultrahigh vacuum (UHV) infrared spectroscopy apparatus dedicated to the spectroscopic characterization of oxides, singles crystals as well as powders, is described. It combines a state-of-the-art vacuum Fourier transform infrared (FTIR) spectrometer (Bruker, VERTEX 80v) with a novel UHV system (PREVAC) consisting of load-lock, distribution, measurement, and magazine chambers. The innovative design allows carrying out both reflection-absorption IR spectroscopy experiments at grazing incidence on well-defined oxide single crystal surfaces and FTIR transmission measurements for powder particles. A further unique feature of the apparatus is the entirely evacuated optical path to avoid background signals from gas phase H2O, CO2, and other species, thus creating the possibility to record high-quality IR data with high sensitivity and stability, an essential prerequisite for monitoring molecular species adsorbed on oxide single-crystal surfaces. The unique performance of this new apparatus with regard to the spectroscopic characterization of adsorbates on oxide single crystals as well as on powder particles is demonstrated by case studies for two different materials, TiO2 and ZnO.
Transformation pathways in the solid-solid phase transitions of iron nanowires
Authors: Sandoval Luis , Urbassek Herbert M.
Published: November 2009

Using molecular dynamics simulations, we study the solid-solid phase transitions induced by strain in Fe nanowires. These show an intricate dependence on the crystallographic orientation of the wire. ⟨001⟩ oriented nanowires exhibit a bcc→fcc transition and preferably follow the Nishiyama–Wassermann path. In ⟨011⟩ and ⟨111⟩ oriented nanowires the transformation is bcc→hcp and proceeds according to the Burgers path. Additionally we show that it is possible to obtain multiple phase transitions accompanied with reorientations.
Evolution of excess wing and β-process in simple glass formers
Authors: Gainaru Catalin , Kahlau Robert , Rössler Ernst A. , Böhmer Roland
Published: November 2009

Dielectric loss spectra of glass forming liquids are analyzed, with emphasis on systems for which a peak due to a secondary relaxation is not immediately obvious. Thus, glass formers are considered for which the high-frequency flank of the α-relaxation peak appears to be dominated by a so-called wing contribution. It is shown that even for such supercooled liquids the shape of the α-peak has to be characterized by two parameters. By performing a series of aging experiments it is demonstrated that the high-frequency flank of the α-relaxation, assumed to follow a power-law behavior, is superimposed by contributions from an excess wing and from a β-relaxation peak. In particular, the excess wing, previously associated with either the α- or the β-relaxation, is identified as a feature that evolves in its own right. It is argued that excess wing and β-relaxation are always present albeit with relative strengths that may vastly differ from glass former to glass former.
Effect of the resonant growth of harmonics on the electron density in capacitively coupled plasma
Authors: Yamazawa Yohei
Published: November 2009

The growth of harmonics is known to occur under the condition of plasma series resonance (PSR). In an actual plasma process chamber, the external circuit also affects the PSR. We experimentally demonstrated the resonant growth of the third and fourth harmonics by tuning a variable capacitor attached to the electrode, and investigated the influence of the growth on the electron density. We observed significant increases in electron density as the amplitude of harmonics grows. The result clearly shows that nonlinear electron resonance heating actually takes place.
Water vapor interaction with silicon oxide films thermally grown on 6H-SiC and on Si
Authors: Soares G. V. , Baumvol I. J. R. , Corrêa S. A. , Radtke C. , Stedile F. C.
Published: November 2009

Thermally induced incorporation of isotopically labeled water vapor (D2 O18) species in 7 nm thick SiO2 films thermally grown on 6H-SiC(0001) and on Si(001) were investigated. Higher incorporation of hydrogen and higher isotopic exchange were observed in SiO2/SiC as compared to SiO2/Si, at temperatures above 600 °C, which can lead to electrical instabilities, especially in high-temperature devices. At any annealing temperature, oxygen is incorporated in the oxide films, reaching the SiO2/SiC interface, in contrast with SiO2/Si. The present observations show that strict control of water vapor contents in SiO2/SiC is mandatory in order to achieve further improvements in the SiC-based device technology.
Anharmonic phonon coupling in vapor-liquid-solid grown ZnO nanowires
Authors: Soudi A. , Lopez R. , Dawson R. D. , Gu Y.
Published: November 2009

We have determined quantitatively third-order anharmonic phonon coupling matrix elements in vapor-liquid-solid (VLS) grown ZnO nanowires, via an analysis of the Raman line shape of the E2high phonon mode. The results suggest that the decay of the E2high phonon into the sum of two acoustic phonons is suppressed in VLS-grown ZnO nanowires compared to bulk ZnO. While further studies are needed to elucidate the origin of this phenomenon, we suggest that isotope effects on Zn vapor transport and diffusion through metal nanocatalysts, processes during the VLS growth, can be contributing mechanisms.
Giant changes in atomic dynamics on microalloying metallic melt
Authors: Chathoth S. M. , Damaschke B. , Embs J. P. , Samwer K.
Published: November 2009

We report unexpectedly strong variations in the relaxational dynamics in a glass-forming metallic melt while microalloying. Analysis of quasielastic neutron scattering data revealed that changes in the values of stretching of the self-correlation function and the temperature dependence of self-diffusivity showed an Arrhenius to non-Arrhenius transition. The intermediate structure of the melts did not show any prepeak or indication of short range order. These observations are correlated with the enhanced glass-forming ability of metallic melts on microalloying.
Study of minority carrier diffusion length in multicrystalline silicon solar cells using photoassisted Kelvin probe force microscopy
Authors: Takihara Masaki , Takahashi Takuji , Ujihara Toru
Published: November 2009

We evaluated the minority carrier diffusion length in multicrystalline silicon solar cells by means of photoassisted Kelvin probe force microscopy to investigate the influence of the multicrystalline material grains and the grain boundaries on solar cell performance. We observed a reduction in the diffusion length in the vicinity of the grain boundary and differences in the diffusion lengths between grains even when considering the influence of lateral diffusion.
High-directivity antenna with small antenna aperture
Authors: Luo Yu , Zhang Jingjing , Chen Hongsheng , Huangfu Jiangtao , Ran Lixin
Published: November 2009

We show in this letter that, by using an inhomogeneous metamaterial shell, it is possible to achieve highly directive emission with a small antenna aperture. The material parameters of the metamaterial substrate are obtained by a nonmonotonic optical transformation. Therefore, a large antenna can be effectively transformed to an equivalent one with much smaller aperture. Full-wave finite-element modeling has been performed to confirm this point. The concept proposed here provides a possible solution to reduce the size of antenna without disturbing the radiation characteristics.
Femtosecond carrier dynamics and saturable absorption in graphene suspensions
Authors: Kumar Sunil , Anija M. , Kamaraju N. , Vasu K. S. , Subrahmanyam K. S. , Sood A. K. , Rao C. N. R.
Published: November 2009

Nonlinear optical properties and carrier relaxation dynamics in graphene, suspended in three different solvents, are investigated using femtosecond (80 fs pulses) Z-scan and degenerate pump-probe spectroscopy at 790 nm. The results demonstrate saturable absorption property of graphene with a nonlinear absorption coefficient, β of (∼2–9)×10−8 cm/W. Two distinct time scales associated with the relaxation of photoexcited carriers, a fast one in the range of 130–330 fs (related to carrier-carrier scattering) followed by a slower one in 3.5–4.9 ps range (associated with carrier-phonon scattering) are observed.
Effects of weaner nutrition on sire and flock rankings: a re-analysis of historical data
Authors: McGuirk B. J.
Published: November 2009

Early work in the 1950s on the wool growth response of sheep from diverse genotypes for wool production in response to varying planes of nutrition at pasture did not show the significant genotype × environment interactions exhibited in later pen studies with the same or very similar genotypes. However, this early study used a log-transformation on all traits to adjust nutritional effects for scale. Re-analysis of the original (i.e. untransformed) data shows that superior genetic merit for clean fleece weight, different sire progeny groups or selection flocks is more apparent when hogget ewes are fed a high plane of nutrition at pasture. However, only in the case of flocks was the interaction statistically significant, and this interaction was insignificant when data were either log-transformed, or when an appropriate test that accounts for scale-type effects was applied. When left untransformed, the data are, thus, in agreement with the subsequent pen studies that examined data on untransformed clean wool production.
Lack of response to garlic fed at different dose rates for the control of Haemonchus contortus in Merino wether lambs
Authors: Strickland V. J. , Fisher J. S. , Potts W. T. , Hepworth G. W.
Published: November 2009

With the increased incidence of parasite resistance to chemical anthelmintics worldwide novel approaches to manage parasite infection, such as medicinal plants and their extracts, are being investigated by the scientific community. The current study tested the effect of three rates of garlic (0.9, 1.8 and 3.6%) in a pelleted ration on Haemonchus contortus in sheep. Thirty-nine Merino wether lambs aged 6 months were divided into five treatment groups, including three garlic dose rates and two control groups that received no garlic. All animals were infected with 4000 L3 H. contortus larvae 3 weeks after allocation to treatments. A positive control group was drenched with abamectin 28 days after infection. The synthetic drench was effective in controlling the parasites, but there was no reduction in either worm egg counts (WEC) or total worm count due to the garlic. The 3.6% garlic treatment had significantly lower (P < 0.05) liveweight, feed intake, body condition score and feed conversion ratio than any of the other treatment groups, suggesting that this level of garlic had a low level of anti-nutritional properties. There was an interaction between faecal WEC and voluntary feed intake over time, with the animals with higher voluntary feed intake having lower WEC over time.
Measures of growth and feed efficiency and their relationships with body composition and carcass traits of growing pigs
Authors: Arthur P. F. , Giles L. R. , Eamens G. J. , Barchia I. M. , James K. J.
Published: November 2009

Data from 53 hybrid (mainly Large White × Landrace) pigs, comprising 18 males, 18 females and 17 castrates, were used to examine the relationships among growth and feed efficiency traits measured in the growing animal, and their relationships with body composition and carcass traits at two target liveweight (90 and 120 kg) endpoints. The data were from individually penned pigs involved in a longitudinal experiment that started when the pigs were 32.4 ± 3.2 kg liveweight and 70 ± 1 days of age (mean ± s.d.). Weekly feed intake and liveweight, and body components data measured at 60, 90 and 120 kg by computed tomography scanning were used. Growth traits studied were: start of test liveweight, average daily gain (ADG), Kleiber ratio and relative growth rate. The feed efficiency traits were daily feed intake (DFI), feed conversion ratio (FCR) and residual feed intake. Body components and carcass traits were the weight of the body components (lean, fat, bone and skin tissues) and their percentages relative to liveweight. Three models were used for residual feed intake. The standard model (RFIstd) had metabolic weight and ADG as explanatory variables for feed intake, RFIadg had only ADG as explanatory variable, and the other (RFIfat) had percentage fat at 60 kg target liveweight included in the standard model. The RFIadg model resulted in R2 values of 36.9, 72.1 and 19.1% for males, females and castrates, respectively. The corresponding R2 values for the RFIstd model were 63.7, 72.1 and 37.1%, and those for the RFIfat model were 86.1, 80.0 and 71.9%. These results indicate that RFIfat may be a better trait to use for efficiency of feed utilisation, especially in castrates. There were significant interrelationships among growth traits (r = –0.46 to 0.98), and also among feed efficiency traits (r = 0.44 to 0.76). Of the feed efficiency traits studied, only FCR was significantly correlated with all the growth traits (r = 0.33 to –0.61), and DFI was correlated with start liveweight (r = 0.43) and ADG (r = 0.57). Growth traits per se were not correlated with body composition and carcass traits at each of the weight-constant target endpoints; however, feed intake was. High DFI was associated with high percentage fat (r = 0.39 to 0.49) and low percentage lean (r = –0.40 to –0.52) at both 90 and 120 kg target liveweights. As with DFI, high FCR, RFIadg and RFIstd were associated with high percentage fat and low percentage lean at both 90 and 120 kg target liveweights. There were no significant correlations between RFIfat and the body components and carcass traits. These results will enable the development of programs aimed at reducing feed costs and improving the economic value of the pig carcass.
A bromochloromethane formulation reduces enteric methanogenesis in cattle fed grain-based diets
Authors: Tomkins N. W. , Colegate S. M. , Hunter R. A.
Published: November 2009

Enteric fermentation has been estimated to be responsible for 64.2 Mt CO2-e, or ~16% of Australia’s greenhouse gas emissions (Australian Greenhouse Office 2007). A bromochloromethane (BCM) formulation, previously shown to inhibit methanogenesis, was included in the diet of Brahman (Bos indicus) cross steers, twice daily in three separate experiments, to determine the effect on methane production, daily feed intake, liveweight (LW) gain and accumulation of residues of BCM in edible tissue.
In the first experiment, the BCM formulation was fed at rates of 0, 0.15, 0.30, or 0.60 g/100 kg LW, twice daily, for 28 days. Methane production (mean ± s.e.), measured over 11 h after feed was first consumed on day 28, was 0.3 ± 0.13 and 0.1 ± 0.03 L/h for animals treated at a rate of 0.30 and 0.60 g/100 kg LW, respectively. This was significantly less (P < 0.05) than for control animals (4.6 ± 0.46 L/h) and animals treated at a rate of 0.15 g/100 kg LW (2.1 ± 0.28 L/h). The dose rate of 0.30 g/100 kg LW was associated with a decrease in methanogenesis by ~93% compared with the control group and was used in subsequent experiments.
The second experiment evaluated the efficacy of the BCM formulation fed at rates of 0 or 0.30 g/100 kg LW, twice daily, for 90 days. Methane production was measured over 24-h periods, on days 30, 60 and 90. For days 30 and 90, methane production was reduced by 60% (P < 0.05) to 4.2 ± 1.82 L/h and by 50% (P < 0.05) to 6.1 ± 0.63 L/h, respectively, for treated animals compared with the control group.
The final experiment determined the effect on LW gain and detectable residues in edible tissue, with animals given the BCM formulation at rates of 0 or 0.30 g/100 kg LW, twice daily, for 85 days. Liver, kidney, depot fat and muscle samples collected 1 and 10 days after the last day of treatment had concentrations of BCM that did not exceed 0.015 mg/kg and were less than the temporary maximum residue limit (0.02 mg/kg BCM), which applies to bovine meat, fat and edible offal. There were no significant differences in LW gain (1.4 ± 0.10 v. 1.5 ± 0.07 kg/day), feed conversion ratio (5.7 ± 0.32 v. 5.4 ± 0.09), hot carcass weight (235 ± 5.0 v. 250 ± 6.5 kg) or P8 fat depth (6.4 ± 0.89 v. 8.1 ± 1.15 mm) between control and treated animals.
The experiments reported here were completed in 2004 before the Australian Government prohibited the manufacture and use of BCM. It is unlikely that the BCM formulation will be available for commercial use to mitigate livestock methane emissions in Australia. Nevertheless, the study has demonstrated that methane emissions were substantially reduced over a 90-day feedlot finishing period. This indicates that alternative antimethanogens with a similar mechanism of action may have practical commercial relevance.
Catchment management and health of coastal ecosystems: synthesis and future research
Authors: Kroon F. J. , Brodie J.
Published: November 2009

Globally, many coastal ecosystems are threatened by a decline in water quality from land-based runoff. However, dynamic and complex biophysical and socioeconomic interdependencies often hamper the reversal of this decline in water quality. This Special Issue illustrates an integrated approach to address deteriorating water quality from land-based runoff in the Tully basin to the Great Barrier Reef (GBR), Australia. Nitrate was identified as the key pollutant, and was mainly derived from sugarcane and banana farms. To achieve GBR water quality targets for chlorophyll a, the dissolved inorganic nitrogen (DIN) load needs to be reduced by at least 80%. Modelling shows that financially beneficial changes to management of sugarcane results in a 50% reduction in DIN load. However, larger reductions would come at a significant cost. An adaptive approach is proposed as a framework to assess (i) the efficacy of implementing the recommended management practices, and (ii) progress against set targets. Quantification of linkages between catchment management and coastal ecosystem health will help inform management strategies based on ecosystem performance measures. Verification of the efficacy of existing and exploration of innovative management strategies, as well as spatial and temporal prioritisation of their implementation, remain critical to achieve coastal ecosystem rehabilitation, including water quality improvement.
Competitive ecology and sustainable production.
Authors: Dixon G. R.
Published: November 2009

This chapter treats the control of weed competition in Brassica crops from an ecological (commonly termed "sustainable") perspective, with emphasis on cultural and chemical control. Some information is also given on the effects of weed competition, the ideal characteristics of a successful weed, the critical periods of competition and the crop-weed competition for nutrients.
Crop protection.
Authors: Csizinszky A. A. , Schuster D. J. , Jones J. B. , Lenteren J. C. van
Published: November 2009

This chapter covers control of weeds, nematodes, insect and mite pests (including those causing chewing damage to seedlings, foliage and fruits or sucking damage to fruits, foliage and flowers), and fungal, bacterial and viral plant pathogens. The first part of the chapter largely concerns crop protection in field-grown tomatoes. This is followed by discussion of the integrated management of pests in greenhouse tomatoes, where biological control measures can be used.
World production, trade, consumption and economic outlook for apples.
Authors: O'Rourke D.
Published: November 2009

This chapter covers the production trends, commercial practices, cultivars, controlled atmosphere storage and market uses of apples. Notes are also presented on the economic outlook for apples including the condurum of export markets, export economics, international trade laws and barriers, global consumption and demand and consolidation in food distribution of apples.
Apple rootstocks.
Authors: Webster A. D. , Wertheim S. J.
Published: November 2009

This chapter covers the species, cultivars and sub-clones of apples used as rootstocks, as well as the different methods of rootstock propagation; the effects of rootstock on the growth and adaptability to environmental conditions of scions; breeding of new apple rootstocks; apple rootstocks propagated from seeds; vegetatively propagated rootstock clones and sub-clones used to control tree vigour; clonal rootstocks used to adapt trees to unfavourable conditions such as plant pathogens and pests, freezing and drought; and use of interstocks and interstems.
Flowering, pollination and fruit set and development.
Authors: Dennis F., Jr.
Published: November 2009

This chapter describes the flowering process in apple, including flower induction, initiation and development, as well as the flowering habit and flower structure, pollination and fertilization, fruit development, seed and fruit growth and fruit maturation in the crop.
Temperature.
Authors: Palmer J. W. , Privé J. P. , Tustin D. S.
Published: November 2009

This chapter covers the effects of temperature, particularly of freezing temperature, spring frosts and spring temperature on the dormancy, assimilation and respiration; fruit, root, leaf and shoot growth; and fruit quality of apples.
Nutritional requirements of apple.
Authors: Neilsen G. H. , Neilsen D.
Published: November 2009

This chapter covers the nutrient requirements of apple, highlighting the direct determination of apple tree nutrient status, nutritional implications of rooting characteristics in the crop, soil testing, augmenting apple nutrition, special nutrient considerations ad individual nutrients required by apple trees.
Ecology and management of apple arthropod pests.
Authors: Beers E. H. , Suckling D. M. , Prokopy R. J. , Avilla J.
Published: November 2009

The ecology and management of the arthropod pests of apples including the fruit, the foliage and the structural feeders are discussed. Pesticide-based and integrated management of the pests are described.
Apple-orchard freeze protection.
Authors: Seeley S. D. , Anderson J. L.
Published: November 2009

This chapter covers freeze protection in apple orchards, touching on the areas of site selection, cultural practices, energetics of the orchard environment, the daily thermal cycle, energy changes in the orchard canopy, water in the orchard atmosphere during freezes, freeze types, monitoring freezes and methods of freeze protection.
Organic apple production - with emphasis on European experiences.
Authors: Weibel F. , Häseli A.
Published: November 2009

This chapter covers the basic principles and legal basis of organic farming, as well as the extent and importance of organic fruit production in Europe, and the supply situation and market outlook for such produce. Conditions favouring the conversion to organic apple production, as well as site requirements, planting systems, choice of rootstocks and cultivars, areas and features for ecological compensation, and nutrient, soil, pest and weed managements for such type of farming are discussed. Notes are presented on organically approved disease and pest control products.
The competitive (micro)environment: the destination and the tourism system.
Authors: Ritchie J. R. B. , Crouch G. I.
Published: November 2009

This chapter examines how the principal elements of the competitive micro-environment are structured in the context of a tourism destination. The basic elements of the microenvironment are the suppliers and supporting industries, tourism and hospitality enterprises, marketing intermediaries and facilitators, customers, and the destination marketing organization and other publics. The chapter concludes with an integration of the impacts of these elements in terms of their overall effect on the destination in question, the effect of competing destinations, and the tourism system as a whole.
Flowering.
Authors: Davenport T. L. , Stern R. A.
Published: November 2009

This chapter reviews the following aspects of shoot and flower development in longan and litchi (Litchi chinensis): types of shoots (vegetative shoots, generative shoots, and mixed and transition shoots); role of growth regulators (cytokinins, auxins, ethylene, gibberellins and abscisic acid) and potassium chlorate in shoot initiation; effects of environmental factors (temperature, drought, nitrogen, and pruning and girdling) on shoot induction; floral morphology; floral development; sex ratio; ovule development and pistil receptivity; pollen viability; and pollination.
Photosynthesis and productivity.
Authors: Menzel C. M.
Published: November 2009

This chapter on photosynthesis and productivity in litchi (Litchi chinensis) and longan covers the following: relationship between photosynthesis and plant development; effects of the environment on photosynthesis; assimilate production and distribution; relationship between fruit growth and leaf expansion; relationship between yield and assimilate supply; relationship between fruit size and yield; relationship between yield and tree size; effects of light and temperature on growth and productivity; effects of planting density and pruning on productivity; and practical aspects of pruning. Tabulated data on the productivity of litchi and longan in China and Thailand, and on the effects of leaf position and stage of development on leaf fresh weight and area, chlorophyll content, net carbon dioxide assimilation, and stomatal conductance in litchi (cv. Bengal) in Queensland, Australia, are presented.
Plant nutrition and fertilizing.
Authors: Menzel C. M.
Published: November 2009

This chapter on longan and litchi (Litchi chinensis) covers the following: effects of soil type, soil pH, salinity and mycorrhizas on fertilizer requirement; factors affecting leaf composition; leaf and soil analyses, and orchard surveys for fertilizer requirement determination; N, P, K, Ca, Mg, Zn, Fe, Cu, B and Mn nutrition (concentration and uptake, effects on productivity, and deficiency symptoms); fertilizer programme for young orchards in Australia; and fertigation.
Harvesting and storage.
Authors: Holcroft D. M. , Lin HeTong Lin HeTong , Ketsa S.
Published: November 2009

This chapter on longan and litchi (Litchi chinensis) describes the following: fruit morphology; fruit respiration and ethylene production; aril composition; pericarp structure and composition; postharvest disorders (pericarp browning, chilling injury and aril breakdown); fruit maturity indices; harvesting, grading and packing; postharvest treatments (sulfur fumigation of fruits, acid treatments for retaining litchi pericarp colour, temperature management, cold storage, reduction of water loss, controlled and modified atmospheres, and disinfestation); and transport and marketing. Harvesting and storage of longan and litchi fruits in Australia are largely covered.
Introduction to risk in agriculture.
Authors: Hardaker J. B. , Huirne R. B. M. , Anderson J. R. , Lien G.
Published: November 2009

This chapter first offers examples of risky decisions in agriculture and discusses their implications. The need to take account of risk in agriculture is then highlighted, and the concepts of risk and uncertainty are explained. The chapter also considers the individuals who need to think about risk in agriculture and then presents a general approach to risk management in agriculture as well as an overview of formal decision analysis.
History and current use of feed additives in the European Union: legislative and practical aspects.
Authors: Doeschate R. A. H. M. ten , Raine H.
Published: November 2009

Whilst the term feed additives encompasses a variety of products, this chapter will concentrate on product groups such as antibiotic growth promoters, coccidiostats and enzymes. These products have been, and are, subject to scrutiny and licensing at European Union (EU) and national level. The history of antibiotic growth promoters serves as a case study for the development of a product group, ensuing legislation, pressure group activity and the subsequent demise of the product group. EU legislation has evolved over the years from a situation of limited scope and relatively relaxed rules to the current system where the scope is being extended to more products and with stricter rules. The current EU regulation (1831/2003) is based on the precautionary principle related to human health, animal health and the environment. At present there are signs that legislation has tightened to such a level that certain products are not available on the EU market, maybe as a result of high costs or delays, due to the registration process. A balance needs to be found between effective legislation regulating the safe use of additives and allowing new product and concept development. From a practical nutritionist's point of view the whole area is very complicated, with several products on the market, and it is unclear whether they are additives in the legal sense or not, but there is a responsibility on the nutritionist to ensure compliance with the law. With antibiotic growth promoters disappearing, several 'replacement' products need to be evaluated, which is another big challenge for nutritionists.
Microbes of the chicken gastrointestinal tract.
Authors: Apajalahti J. , Kettunen A.
Published: November 2009

The gastrointestinal tract of an adult chicken is inhabited by up to 1013 bacteria. This microbiota has a wide metabolic potential and it affects both the nutrition and health of the host. The microbial populations in the chicken gut grow rapidly, the density plateauing within 3-4 days of hatching. The structural evolution, however, is likely to continue for the entire life of a broiler chicken. The effect of microbes on the commercial aspects of a poultry enterprise is apparent to the farmer only in extreme cases. Known pathogens, such as Clostridium perfringens and Escherichia coli, may reduce bird growth and liveability and human pathogens, such as Salmonella enterica, may lead to carcass condemnation and reduced income. Most of the time, however, the effect of bacteria is less obvious to the grower, and one or many of the unidentified bacterial species present may cause non-specific enteritis. The composition of the intestinal bacterial community has been studied by many researchers. The methods used here varied markedly and, therefore, it is often impossible to know whether the varying observations are due to geography, feeding regimen, bird management or to the methods used for microflora analysis. The microbial community of the caecum is far more diverse and less well characterized than that of the crop and small intestine. The abundance of bacteria is significantly affected by feed composition and ingredients. We have numerous means of modulating the microflora and these can be applied as soon as knowledge from well-designed studies unveils the correct bacterial targets.
Effect of non-starch polysaccharidases on avian gastrointestinal function.
Authors: Bedford M. R.
Published: November 2009

Non-starch polysaccharidases, which include cellulases and xylanases, are routinely used in poultry diets containing wheat, barley, oats, triticale and rye and, more recently, maize. The beneficial responses observed may be based on one or more of three proposed mechanisms of action, namely: (i) cereal endosperm cell wall hydrolysis; (ii) reduction in intestinal viscosity; and (iii) provision of fermentable oligomeric substrates as a result of cell wall hydrolysis. Since each mechanism elicits a specific series of responses at the intestinal level, and the extent of involvement of each will vary depending upon circumstances, there are a variety of potential responses observed. Changes in intestinal function may be driven by changes in nutrient supply and/or changes in the physico-chemical conditions (the viscosity of the intestinal contents, the nutrient-binding ability of the fibre fraction and the thickness of the unstirred water layer) of the intestine. Nutrient supply encompasses not only improved nutrient extraction by the host, and thus reduced availability for the intestinal flora, but also the provision of oligomeric substrates through cell wall hydrolysis. As a result of such changes there may be subsequent, interrelated changes in the structure and size of the intestinal tract, in pancreatic enzyme secretion, in the quantity and chemistry of mucin secreted and in the quantity and species distribution of resident intestinal flora. The qualitative and quantitative changes in intestinal function observed are very much dependent upon the status in the absence of enzyme, which highlights the fact that responses upon use of enzymes are variable, being greatest in poor-quality diets.
Competitive exclusion in poultry production.
Authors: Schneitz C.
Published: November 2009

The concept of Competitive Exclusion or CE, sometimes also described as the 'Nurmi concept', involves treatment of newly hatched chickens with mixed bacterial preparations originating from the gut of healthy adult birds to control intestinal disturbances. The treatment has also been given successfully to older birds after therapeutic doses of antibiotics to regenerate the intestinal microflora. CE treatment is usually applied by spraying, but can also be given via the first drinking water. The concept of CE was originally developed to control Salmonella in growing chickens but has, with time, been expanded to involve several other enteropathogens like chicken and human pathogenic Escherichia coli, Clostridium perfringens, Listeria and Campylobacter. The chicken intestinal flora has also been shown to be efficacious in other avian species like turkey, quail and pheasant. The mechanisms by which the intestinal bacteria inhibit the invasion and proliferation of enteropathogens include competition for receptor sites, elaboration of inhibitory compounds and competition for nutrients or stimulation of the immune system. In addition to pathogen control, it has been shown in field studies that CE treatment enhances the growth and decreases the mortality of birds and improves the feed conversion. The nutritional effects of the treatment have been confirmed in well-controlled laboratory studies. Increased bacterial resistance to antibiotics in humans has caused an increase in public and official interest in abandonment of the use of growth-promoting antibiotics. Competitive exclusion is a reliable alternative because the treatment is fully biological, it does not leave any residues and only one treatment on the day of hatch is normally enough.
The genetics of modern commercial poultry.
Authors: McKay J. C.
Published: November 2009

Genetically improved strains of poultry have been a major contribution to the success of the poultry industry, which is a major source of animal protein for the human population in most countries of the world. Improvements in health, nutrition and environmental management have also contributed to improved performance, but the majority of the change has been attributed to genetic improvement. Egg production has been improved consistently since the late 1930s, and the industry continues to improve the efficiency of laying hen production by at least 1% per year. This requires the simultaneous improvement of multiple traits, including egg number, egg size, liveability, persistency and mature body weight. There is also continuing progress in uniformity of egg size and colour and freedom from defects. In broilers, combined selection for growth, body composition, feed efficiency and liveability continues to deliver 2-3% improvement per year in the efficiency of meat production. Other traits such as robustness, specific and general disease resistance, and absence of metabolic defects have also contributed to this progress.
Incubation and hatching.
Authors: French N. A.
Published: November 2009

The emphasis of poultry incubation research since the late 1980s has focused on four different themes, namely: (i) the relationship between incubation temperature and embryo temperature; (ii) how to engineer commercial incubators to meet the requirements of the embryo; (iii) the effect of genetic changes to poultry breeds on their incubation requirements; and (iv) the effect of incubation environment on the post-hatch performance or epigenetic adaptation. It is the intention of this short review to focus on these four areas of research and to discuss how they are affecting commercial practice. A simple systems model is used to describe how embryo growth and metabolism, the properties of the egg in which the embryo develops and the environment of the incubator interact to determine the embryo temperature. The model shows that the relationship between the egg and its incubation environment is a dynamic process, with the embryo responding to its incubation environment but also affecting the environment. Our understanding of these interrelationships has resulted in better design of artificial incubators and the development of methods to directly measure the response of the egg to its environment. The third section of the review discusses whether the genetic improvements to poultry in both egg and meat production have altered the incubation environment of the embryo. It is concluded that there are differences in embryo metabolic rate between genetic lines, which may impact on the optimum incubation environment. It was also noted that the mechanism by which genetic selection had affected embryo metabolism was not yet understood. The last section of the chapter discusses the possibility that post-hatch performance can be affected by the incubation environment and presents evidence to show that this may indeed be the case.
Photoperiod and control of breeding.
Authors: Lewis P. D.
Published: November 2009

Photoperiod is the most important environmental manipulator of sexual development and reproductive activity, and changes in photoperiod exert far greater effects on sexual maturation than constant photoperiods. The critical daylength to initiate sexual maturation appears to be common for all species of poultry at between 10 and 11 h, with a saturation daylength of between 13 and 14 h. The photoperiodic response varies with the type of poultry and is principally dependent on whether or not the bird exhibits photorefractoriness and if so in which form. Photorefractoriness is a condition that, in its extreme, prevents gonadal maturation in the year of hatch and limits breeding to spring and early summer. Birds are hatched photorefractory and need a period of short days to dissipate the condition, the time requirement for which varies with photoperiod and the degree of feed restriction. Reproductivity is subsequently ended by the onset of adult photorefractoriness. Geese and game birds exhibit absolute photorefractoriness and have a breeding season limited to about 4 months. Their sexual maturity is indefinitely delayed when reared on long days. Turkeys, and probably Muscovy ducks, exhibit relative photorefractoriness, become sexually mature in their first year and suffer no more than a 3- to 4-week delay in maturity when not reared on short days (below critical daylength). Turkeys do not normally have their feed intake restricted and so require only about 2 months of short days to become photosensitive. Broiler breeders also exhibit relative photorefractoriness, but because their feed intake during rearing is severely restricted, they need 4-5 months of short days to become photosensitive. Meat-type ducks do not exhibit photorefractoriness and rearing on short photoperiods is not essential.
Immune protection of the hatchling.
Authors: Butter C. , Walter H. J.
Published: November 2009

It has become clear that, although their immune responses are impoverished compared with those of adults, neonates are capable of mounting adaptive immune responses, which are dependent on the conditions of antigen exposure. Whilst embryonic vaccination of chicks can successfully induce adaptive immunity, the precise mechanisms whereby this is generated in the face of immune unresponsiveness remain to be elucidated. This chapter reviews existing data and further describes the ontogeny of humoral and Th1 cytokine responses in neonatal chicks and their enhancement through manipulation of the immune system. Neonatal chicks are capable of producing age-related Th1 cytokine profiles following parasitic infection. This contrasts with the mammalian system, in which neonates mount Th2-biased cytokine responses following antigen challenge. However, humoral responses are slow to develop, only being detected in juvenile birds from 18 days post-hatch in response to T-dependent non-replicating antigen. We suggest that the immaturity of this response is due to a defect in the neonatal B-cell population. The manipulation of immune function during the neonatal period, a time when chicks are uniquely vulnerable to infection, offers the prospect of improved methods for prevention and treatment of disease.
Managing current disease challenges in breeders.
Authors: Collett S. R.
Published: November 2009

This article discusses the current global disease challenges; impact of diseases on breeder performance; managing disease challenges through the implementation of biosecurity and preventive programmes; cost of health programmes; and disease control programmes against various bacterial and viral diseases in breeder flocks.
Poster abstracts.
Authors: Hocking P.
Published: November 2009

A series of abstracts of papers on various topics related to fowl breeding and production, including those on genetics, reproduction, feeding, nutrition and performance of broilers and laying hens, is presented.
Low-chill cultivar development.
Authors: Topp B. L. , Sherman W. B. , Raseira M. C. B.
Published: November 2009

This chapter focuses on the breeding of low-chill peach cultivars adapted to the subtropics, although they may be grown in temperate environments (in the absence of spring freezes that kill the bloom) or in tropical highlands. Topics covered are: reasons for breeding low-chill cultivars; history of low-chill cultivar development; current low-chill breeding programmes (New South Wales and Queensland, Australia; São Paulo, Brazil; Mexico; South Africa; Taiwan; Thailand; and California, Florida and Texas, USA); common objectives in low-chill peach breeding (low chilling requirement, time of flowering, flower bud density, blind nodes and bud drop, fruit development period, fruit shape, fruit firmness and disease resistance); and management of low-chill breeding populations (hybrid seed production, seedling populations, and testing advanced selections).
Fresh market cultivar development.
Authors: Okie W. R. , Bacon T. , Bassi D.
Published: November 2009

This chapter focuses on the cultivation and breeding of peach cultivars for fresh consumption in the USA (north-eastern USA and Canada, south-eastern USA and California), Europe (Bulgaria, France, Greece, Hungary, Italy, Poland, Romania, Serbia, Spain, Ukraine and former Soviet states), and Pacific and African regions (China, Japan, Korea, New Zealand and South Africa).
Nutrient and water requirements of peach trees.
Authors: Johnson R. S.
Published: November 2009

This chapter focuses on the nutrient and water requirements of peach. Topics covered include diagnostic methods for nutrient status determination; effects of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, zinc, boron, iron, manganese, and copper on crop performance; and imposing of moderate water stress in peach orchards as a strategy for improving crop productivity.
Harvesting and postharvest handling of peaches for the fresh market.
Authors: Crisosto C. H. , Valero D.
Published: November 2009

This chapter discusses peaches in relation to its: fruit composition and antioxidant capacity; deterioration problems; fruit maturity; temperature requirements and management; field harvesting, hauling and packaging; cull utilization; and fruit handling at retail distribution.
Physiology of crop growth, development and yield.
Authors: Brewster J. L.
Published: November 2009

This chapter starts with an outline of the principles determining crop yields and how they apply to onions. It gives a context within which to discuss how environmental and internal factors control successive phases of development from seed, through shoot growth, to the harvested bulbs or shoots. Inflorescence initiation and development and seed formation are then considered, along with interrelationships between vegetative and floral growth. Models based on physiological relationships that predict crop growth, development and yield are then discussed. Onion, the most intensively studied crop, is considered primarily, followed by sections on each of the other edible alliums, which behave similarly to onion in many ways.
History, uses and production.
Authors: Creasy G. L. , Creasy L. L.
Published: November 2009

This chapter discusses the geographical origins, natural growth conditions, historical cultivation and uses (for wine and related fermented products such as table grapes and raisins) of grapevines. The family, genus, species and related plants are described. Tabulated data on grape-producing countries are provided.
Grapevine growth and fruit development.
Authors: Creasy G. L. , Creasy L. L.
Published: November 2009

This chapter reviews the growth cycle (including branching, flower initiation, fruit set, fruit development and berry maturation) of grapevine, along with factors (such as plant growth regulators, environment and climate) that influence it. The fact that the vine is a perennial plant means that management is quite different to that for annual crops, as well as there being unique aspects to cultivating young versus established vines. An overarching concept, that of vine balance, is introduced as it has implications for decisions made from the very start of vineyard planning as to how the weather affects the vine after harvest. Fruit quality parameters are also mentioned, particularly with reference to grape berry maturation.
Climatic requirements.
Authors: Creasy G. L. , Creasy L. L.
Published: November 2009

This chapter reviews some of the physiological requirements (such as cold hardiness and frost tolerance) of grapevines with regard to their environment, with an eye to commercial production. The heat, light, water and soil requirements of the crop are described. The effect of climate change on grape production and quality is briefly discussed.
Vineyard establishment.
Authors: Creasy G. L. , Creasy L. L.
Published: November 2009

In this chapter, the process of putting in a vineyard is followed from first thoughts to making sure that the vineyard gets off to a healthy start, ready to produce as much high-quality crop as it can for the life of the vineyard. The site, climate, soil and other factors (including land cost/availability/zoning, likely pests and diseases, proximity to existing industry infrastructure, presence of skilled and unskilled labour, accessibility to markets or shipping ports, reputation of the region, pollution concerns from neighbouring activities or previous cropping, water availability and quality, natural rainfall and its timing through the year), as well as choice of rootstocks are considered. Propagation of grapevines through cuttings, layering and grafting is briefly described.
Seasonal management.
Authors: Creasy G. L. , Creasy L. L.
Published: November 2009

Once a vineyard has been established there is ongoing management to keep it in top producing form. In many ways, this process starts at pruning and matching the vine to the trellising system, as this sets the vine up for producing fruit in the following year. There are then many other management interventions that can be used during the growing season, including those dealing with the canopy, any cover crop, water application (irrigation) and other methods that fine-tune the grape product. Finally, determining when and how to harvest the crop caps off a season of preparation. Other management practices are also described, such as girdling, fruit thinning and application of growth regulators.