bluuebunny/crossref_metadata_2025_split huggingface dataset:
Setting research agendas for Kenya
Authors: Ndiritu C. G. 
Published: June 2019

AbstractAs resources available for agricultural research and development become increasingly scarce, the Kenya Agricultural Research Institute (KARI) has taken steps to define a clear research agenda. This effort has taken the form of formal priority setting in various research programmes. Priority setting is a key step in the formulation of a research agenda because priority setting, almost by definition, increases the efficiency and relevance of our research programmes by adding valuable structure to our wide information base on agro-ecological and socio-economic conditions in the country, by focusing attention on client constraints and by specifying the potential impact of research on these constraints.The process of establishing clear and systematic priorities in our research programmes allows us to take a proactive rôle in soliciting government and donor support for areas identified as vital to agricultural development efforts. Perhaps most important, the priority setting processes developed at KARI have helped to broaden participation in formulating our research agenda by including a wide range of stakeholders and clientsfrom outside the Institute and in the process widened and deepened our constituency base.Within specific programmes, the priority setting process has comprised five interrelated and cumulative steps: (1) compiling the information base on relevant commodities and regions; (2) identifying programme research target zones and research themes; (3) eliciting the potential for technology generation and adoption; (4) estimating research-induced social benefits; and (5) establishing research priorities and medium-term resource allocation guidelines with programme stakeholders.All but a handful of our commodity research programmes, which include a number of livestock research programmes, have completed this five-step procedure. A similar process has been developed for regional and factor-based research programmes, which should have clear research priorities and resource allocation guidelines in 1998. Once all programmes have completed their respective priority setting activities, we will embark on an Institute-wide priority setting exercise that will pit programme against programme with a view to establishing a coherent set of priorities for the entire organization.
Global food demand and the contribution of livestock as we enter the new millennium
Authors: Delgado C. L. , Courbois C. B. , Rosegrant M. W. 
Published: June 2019

AbstractPeople in developed countries currently consume about three to four times as much meat and fish and five to six times as much milk products per capita as in developing Asia and Africa. Meat, milk and fish consumption per capita has barely grown in the developed countries as a whole over the past 20 years. Yet poor people everywhere clearly desire to eat more animal protein products as their incomes rise above the poverty level and as they become urbanized. Growth in per capita consumption and production has in fact occurred in regions such as developing Asia and most particularly China. Per capita consumption of animal proteins and use of cereals for animal food in Asia have both grown in the 3 to 5% per annum range over the past 20 years. By 2020, according to the International Food Policy Research Institute's IMPACT model projections, the share of developing countries in total world meat consumption will expand from 47% currently to 63%. Of the global total projected increase in meat consumption, 40% is from pork, 30% is from poultry and 24% is from beef. The latter helps mitigate the otherwise much larger decline in real beef prices expected through 2020. Projected annual growth in meat consumption in China of 3.2% per annum through 2020, up from 8.3% per annum from the early 1980s to the early 1990s, drives these results.A rapidly expanding supply of feedgrains will be essential to achieving the desired production increases for livestock products without undue upwards pressure on grain prices, especially in view of the rôle of monogastrics and the relative increase in industrial production in developing countries. IMPACT projections under various technical and economic assumptions suggest that there is enough production supply response in world systems to accomplish these production increases smoothly. Sensitivity analysis of the impact of restrictions on China's ability to produce more feedgrains illustrates that in a system of linked global markets for cereals and livestock products, such restrictions are not effective at lowering Chinese livestock consumption, which is driven by global trade in manufactures, although they do lower Chinese livestock production. The resulting imbalance raises world food costs by one-third in 2020 over anticipated levels, encourages increased livestock exports from Latin America, discourages livestock exports from the USA and reduces meat and cereals imports and consumption in the poorer countries of Africa and Asia.
In vitrotechniques as tools to predict nutrient supply in ruminants
Authors: Tamminga S. , Williams B. A. 
Published: June 2019

AbstractIn vitro techniques are widely used to predict the nutritive value of foods for farm animals. However, food evaluation systems are moving towards systems based on nutrient flows rather than on energy or protein. Nutrients are supplied via the digestive tract and presently available in vitro methods are inadequate to simulate the complicated and non-steady-state processes in this tract. This is partly due the lack of adequate in vivo reference values and partly due to a too-high degree of standardization and simplification. Future developments should therefore aim to develop in vitro systems which closely monitor the dynamics of the digestive processes. Adequate interpretation of the results may require sophisticated mathematical models.
A history ofin vitrotechniques
Authors: Minson D. J. 
Published: June 2019

AbstractRegressions relating in vivo digestibility to chemical composition of the food have residual standard deviations that are unacceptably high. The development of the two-stage in vitro technique inoculated with rumen liquor (Tilley and Terry, 1963) allowed dry-matter digestibility to be predicted with greater accuracy. This success was followed by a series of developments which replaced rumen liquor with inoculum produced from fresh or preserved faeces collected from sheep or cattle. Other methods used inoculum from a continuous fermentation containing rumen micro-organisms and enzymes produced by fungi. Another modification was to use gas production as a measure of in vitro digestion. The range of nutritional problems that could be measured by in vitro techniques was extended to include the estimation of voluntary food intake and protein degradation. All these in vitro techniques require standardization using food samples that have previously been analysed in vitro or offered as the sole diet to animals. The relative merits of these two calibration methods are discussed. Special facilities are required for storing and distributing these standard foods.
A review of current nutritional models: what we need to measure
Authors: Cottrill B. R. 
Published: June 2019

AbstractA common feature of nutritional models developed in the last three decades is that estimates of energy and protein are generally made independent of each other, even though interactions between them are recognized.Most of the energy systems have adopted metabolizable energy (ME) or net energy (NE) as the unit for energy evaluation. Accurate measurement of the ME content of a food requires in vivo digestibility measurements using cattle or sheep, with methane losses either measured or predicted. This approach is clearly unsuitable for routine food evaluation and most systems predict the ME content from chemical analyses, using regression equations derived from calorimetric measurements.The new generation of protein systems recognize the need to consider, separately, the energy and nitrogen requirements of the rumen micro-organisms and the protein requirements of the host animal. Despite this common base, systems differ markedly in estimates of energy supply to rumen bacteria, the degree to which dietary protein is degraded in the rumen, microbial protein yield and the digestibility of the microbial and undegraded dietary protein.Although empirically based, current protein systems contain dynamic elements relating to rates of fermentation and protein degradation. In most cases, data have been derived using the in situ nylon bag technique, although this has major limitations. Recent developments in the gas production technique suggest that this approach has the potential for describing fermentation and degradation rates of individual foods.To be effective, energy and protein systems need to describe foods in units that are both easily understood by non-specialists and can be measured using procedures that are rapid, reliable and cost effective. Near infra-red reflectance spectroscopy (NIRS) can be both rapid and cost effective and there is evidence that it may be able to predict not only proximate analyses but also dynamic characteristics of foods.
The development, use and application of the gas production technique at the DLO Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands
Authors: Cone J. W. 
Published: June 2019

AbstractAt the DLO Institute for Animal Science and Health (ID-DLO) in Lelystad a fully automated time related gas production apparatus has been developed, using sensitive electronic pressure transducers in combination with electric micro-valves to release overpressure during the incubation. In this very sensitive system, no gas accumulation and pressure build up takes place. Each valve opening represents a known amount of gas, set at about 0-5 ml. By recording each valve opening the kinetics of degradation can be studied. Routine analyses are performed with rumen fluid from wether sheep, diluted with buffer (1 volume rumen fluid/2 volumes buffer). The gas production profiles are fitted with a multi-phasic model, which exists for most foods of three subcurves. It is shown that the first subcurve of gas production is caused by fermentation of the soluble fraction of a food, whereas the second subcurve is caused by fermentation of the non-soluble fraction. The third subcurve, starting after about 15-20 h of incubation, is not related to fermentation of the substrate, but is caused by gas production in the rumen fluid itself, as it is also observed in rumen fluid without substrate. It is discussed whether gas production profiles should be corrected for a blank or not. Gas production profiles of substrates with a high content of protein should be corrected for ammonia synthesis, as the ammonia inhibits the release of gas from the saturated carbonate buffer. The used gas production technique and the used three-phasic curve fit model show a high relationship with existing food evaluation techniques, like the Tilley and Terry technique and the nylon bag technique. Comparing the gas production technique within vivodata has only been done with a very limited number of samples. At ID-DLO the gas production technique is used at present as a research instrument to study the fermentation characteristics of ruminant foods, the technique is used in breeding programmes of grass and maize, to search for optimal degradable genotypes, and in silage research. Moreover, the technique is used to study rumen physiology, with special emphasis on carbohydrate and protein fermentation and the balance between both. The gas production technique proved to be a cheap and accurate technique to determine differences in fermentation kinetics. The gas production equipment cannot only be used to study the fermentation in the rumen but can be used to study all kinds of fermentation, such as colon fermentation in all kind of animals and humans.
Net alkali requirement of foods of different acidogenicities in a continuous culture system
Authors: Wadhwa D. , Dewhurst R. J. , Dhanoal M. S. , Borgida L. P. 
Published: June 2019

Maintaining blood pH within a narrow range is the first priority of an animal compared with the other body functions (Erdman et al., 1982). Under normal forage feeding conditions, maintenance of rumen, blood and cellular pH within safe ranges poses no problem for the animal. However, the inclusion of high levels of readily fermentable carbohydrates is often necessary to meet the energy requirements of high producing ruminants. Unfortunately, these foods can result in low rumen pHs which can have adverse effects on animal health and performance. When saliva flow is inadequate to counteract excessive ruminal acidity, the use of buffers may be justified. The in vivo studies reviewed by Muller and Kilmer (1979) have shown that the responses to the addition of buffers to dairy cow rations has been variable and inconclusive.Part of the reason for this uncertainty is because buffer requirements cannot be accurately predicted from the chemical composition of foods, since measurements such as buffering capacity (BC) take no account of changes during fermentation such as the production of volatile fatty acids (VFA), ammonia and the disappearance of the fibre which confers BC. An in vitro approach was adopted for this work since it is difficult to conduct in vivo experiments in this area, owing to the health risks to cows as well as difficulties in distinguishing diet effects because of the strategies employed by cows to overcome excess acidity (e.g. eating rate, salivation, rumination).
Current and future potential of alternative techniques
Authors: Givens D. I. , Gill M. 
Published: June 2019

AbstractRuminant animal production faces numerous challenges and it seems that both economic and biological benefits will be derived from moving food characterization from simple energy and protein-based approaches to those which assess nutrient supply in some detail. In vitro systems will need to reflect this change and this paper considers in particular, the need for estimations of rumen volatile fatty acids and microbial protein supplies. Emphasis is placed on the possibility that in vitro techniques can be used to provide biochemical data which can themselves be used in mathematical models of wider processes. This paper also examines the need for in vitro techniques to reflect the microbial!animal response to the physical structure of foods and also the requirement for in vitro approaches which ask why a food has a certain value rather than simply what the value is. In vitro techniques also have a substantial role outside the digestive tract in predicting factors such as voluntary food intake and some aspects of tissue metabolism and some of these aspects are considered. Tor practical application in vitro techniques will need to provide value for money and be compatible as parameters in mathematical models to have an impact at farm level. In this regard physical in vitro techniques such as NIRS seem to have enormous potential.
Use of an in vitro gas production method to study kinetics of rumen dry matter degradation of forages
Authors: Dhanoa M. S. , Tanner J. C. , Owen E. , Theodorou M. K. , Winugroho H. M. 
Published: June 2019

In addition to assessing rate and extent of gas production from fermenting forages in vitro with rumen micro-organisms, gas production methods (e.g. Theodorou et at, 1994) may be used also to study the degradation kinetics of forage dry matter and its fractions. As the substrate dry matter can be lost only through fermentation or solution, this removes the error inherent in the polyester bag method caused by fine particle losses from bags being deemed part of the ‘soluble’ fraction.The pressure transducer technique (PTT) of Theodorou et al. (1994) was used to measure gas production from nine tropical forage samples (Table 1). Nine bottles were prepared from each of the forage samples. Two bottles of each forage were harvested after 8, 24 and 48 h of incubation and a further three bottles at 72 h, to determine dry matter (DM) and organic matter (OM) losses. The same nine forages were assessed using the polyester bag method (Mehrez and Ørskov, 1977) to obtain DM and OM disappearance after rumen incubations of 4, 8, 24, 48 and 72 h. The soluble fraction was determined by hand washing. The reproducibility of measured losses, at given times, was examined using concordance (rc) correlation (Lin, 1989) and mean square prediction error (MSPE, Bibby and Toutenberg, 1977). Also the simple exponential model was used to estimate the fractional rate of DM degradation (kd) and asymptote A (%) for each forage and the values obtained using PTT (kd,ptt) and in situ (kd,bag) compared using rc and MSPE.
Chemical composition, dry matter and crude protein digestibilities of some tropical browse plants estimated in vitro
Authors: Shayo C. M. , Udén P. 
Published: June 2019

Browse plants are generally regarded as important food resources for ruminants in the tropics due to their high levels of nitrogen. Particularly during the dry season livestock eat browse which may contain considerable amounts of phenolic compounds including tannins at levels of up to half of the dry matter (Reed, 1986). Tannins are known to react with proteins to form rumen undegradable or totally indigestible complexes.A uniform food fraction is assumed to have the same true digestibility irrespective of source and level in the food. In the test of uniformity developed by Lucas (1964) and applied by Van Soest (1967) the digestible fraction per unit food is regressed upon its concentration in the food. The slope of the line gives its true digestibility, the intercept, the potential metabolic fraction and the variation around the regression line explains the extent of uniformity of the fraction.
Near infrared reflectance spectroscopy wavelengths for selecting barley for the genotypic feeding value of its straw
Authors: A. V. Goodchild  , F. J. El Haramein  , S. Ceccarelli  , E. F. Thomson  
Published: June 2019

In the semi-arid parts of west Asia and north Africa, barley straw (Hordeum vulgareL. subsp. vulgare)and cereal stubbles provide between one-quarter and one-half of the metabolizable energy (ME) offered to sheep. In barley straw, voluntary straw dry-matter (DM) intake (VSI) is a good predictor of body weight gain (R2 = 0.85; data of Capper et al., 1989). This varies according to location and year (CV = 0.30 to 0.40) and varies genetically, with an average genotypic CV of 0.07, which can exceed 0.10 in wet years. Genotype X environment interactions in VSI are important (Table 1).A genetically high VSI is advantageous in cool, wet, favourable growing conditions, when VSI is normally low. In drought conditions, VSI is high, genetically varies relatively little (Table 1) and is less important for the farmer than straw and grain yields. Barley breeders working in drought-prone environments prefer to do most of their selection for yield in dry conditions (Ceccarelli, 1993). Breeders are increasingly selecting for high VSI but wish to focus their testing plots in dry areas. Therefore they need indirect tests that indicate the nutritive value of straw when it is grown in wet environments.
Prediction of 48 hin situdegradability from chemical analyses andin vitrofermentation of sugar cane bagasse treated with varying levels of electron irradiation and ammonia
Authors: Vitti D. M. S. S. , Abdalla A. L. , Filho J. C. S. , del Mastro N. L. , Mauricio R. , Owen E. 
Published: June 2019

Sugar cane bagasse is produced in large quantities in Brazil. The cultivated area of sugar cane in recent years has been around 4.2 X 106ha/year, with a production of about 270 X 106t/year of cane. As each tonne of cane produces around 300 kg of bagasse by-product, a large quantity of bagasse is generated.Bagasse is of low dry matter (DM) digestibility (about 250 g/kg), because of lignification. Efforts have been made to improve the digestibility of bagasse using treatment with chemicals (sodium hydroxide, ammonia) or steam (Abdallaet al.,1990). Although steam and pressure treatments have improvedin situdegradability, intake and digestibility in cattle were disappointing (Melloet al, 1989). Recently treatment of bagasse with irradiation and ammonia have been investigated.
A survey of some in vitro methods used for animal nutrition research and extension work in Europe: the differences between the references and the truth
Authors: Mills C. R. 
Published: June 2019

As animal nutritionists are generally very cautious about using chemical analysis only for defining nutritional needs for livestock and as in vivo experiments are long, costly and subject to animal welfare legislation, much emphasis is placed on various in vitro analyses which are often regarded as being very informative in the absence of in vivo data. In vitro analyses may be applied to dry- (DMD) and organic-matter (OMD) digestibility and crude protein (CP) degradability (DG) and may involve ‘live’ cultures such as rumen fluid or gastric juices or ‘dead’ extracts containing enzymes. As part of an EU-funded Concerted Action (see Acknowledgements), a survey of the methods adopted for in vitro determinations (in vitro OMD, in vitro DG) for ruminants, pigs and poultry is underway: this paper presents a progress report of the information received to date concerning ruminant methods.The participants in the Concerted Action were asked to provide details of the in vitro methods actually in use in their countries, with particular attention to the methods used by the so-called Feed Information Centres (i.e. Feed Evaluation Units) for routine analyses (i.e. not experimental work). The participants supplied details of modifications and/or references to methods and this information was collated and circulated for checking and comment.
Food production — the price being paid by farm animals
Authors: Ward L. G. 
Published: June 2019

AbstractThere is varying understanding about life for farm animals. The majority of farm animals have gone from the land, only to be caged, crammed and confined behind the closed doors of the factory farm — battery hens sentenced to remain for life in wire cages, broiler chickens reared in overcrowded conditions and pigs tethered and confined in narrow stalls or in equally narrow farrowing crates. Other farm animals are sent abroad to the cruel veal crate system of continental Europe or to abattoirs where welfare standards, both during transportation and at the time of slaughter, are often appallingly low. Many of the animals slaughtered in Britain, or for the live export trade, are processed through live auction markets. A recent investigation revealed many instances of infringements of the regulations governing the treatment and welfare of animals at markets. The controversy over BSE and the cloning and genetic engineering of farm animals have all resulted in close scrutiny and inquisitions by the public into the conditions in which our farm animals are reared, treated and slaughtered. Those involved in the food industry and also those who care about the welfare of animals and recognize their sentiency must take action to ensure that the animals are reared with due thought to their behavioural needs and well being and, when the time comes, granted a quiet and humane death. For far too long in food production programmes farm animals have paid a heavy price in suffering. From birth to death, farm animals must be treated humanely and with respect.