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A study to explore the perceptions that South African chiropractors have regarding the perceived role and impact of research within the professionGordon, Julani January 2012 (has links)
Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2012. / The Chiropractic profession has made significant progress with regard to the production of high quality and clinically relevant research in the last 20 years. This correlates with a spike in development within the chiropractic profession as well as its acceptance by the medical fraternity and public. The responsibility for continuing this positive trend is dependent on the chiropractic graduates and practitioners of the future. Therefore, it is important to establish the current perceptions and utilization of research by Chiropractors, so that future research can be built around the needs and requirements of today’s practitioners, thereby ensuring the profession’s continued development and future in health care. The aim of this study was to determine the perceptions that Chiropractors have of research and its relevance / utilization in practice.
Method: The study was a quantitative questionnaire based, self administered survey. The sample group included all Chiropractic practitioners currently practising in South Africa (N=515).
Results: There was a response rate of 35% (n=174). The results indicated that the perception of research was very positive overall, with the strongest positive response being that research adds credibility to the profession. However, most respondents disagreed with the statement that chiropractors who had done research had an advantage above those who had not. There was a positive, albeit weak correlation between perceptions and utilization of research, indicating that as perceptions increased, so did utilization of research. The area of greatest concern was that even though a high degree of research utilization was reported by chiropractors, research was least likely to be used to change conditions, policies or practices in practice.
v
Conclusion: The most significant factors associated with positive perceptions and utilization were found to be publishing in a journal and receiving referrals from other health care practitioners. Chiropractors who indicated an interest in doing research again were also very positively linked to utilization. It would seem that even though chiropractors perceive research positively, their implementation into practice has some hurdles that impede the full integration of research into practice. As very few demographic and personal attributes of the South African chiropractor were found to be primarily responsible for low utilization of research in practice, it can be hypothesised that the factors impeding research implementation are most likely environmental in nature.
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PULSE SHAPED CONSTANT ENVELOPE 8-PSK MODULATION STUDYTao, Jianping 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The most bandwidth-efficient communication methods are imperative to cope with the congested frequency bands. Pulse Shaping methods have excellent effects on narrowing bandwidth and increasing band utilization. The position of the baseband filters for the pulse shaping is crucial. Filters after the modulator will have non-constant envelope and before the modulator will have constant envelope. These two types have different effects on narrowing the bandwidth and producing bit errors. The constant envelope 8 PSK is used throughout the simulations and is compared with the non-constant envelope results. This work provides simulation results of spectrum analysis and measure of bit errors produced by pulse shaping in an AWGN channel.
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Studies on the suitability of Jatropha curcas kernel meal as an alternative protein source in diets for carp (Cyprinus carpio) and tilapia (Oreochromis niloticus)Krome, Carsten Alexander January 2014 (has links)
Aquaculture production is increasing annualy and wild fisheries for fishmeal production remain stagnant. As a consequence, extensive research has been deployed to reduce dietary fishmeal inclusion in feeds of farmed species. Usage of alternative protein sources derived from plants continues to increase with the most popular sources being oilseeds, legumes and cereal grains. The downside of these sources is that most of them could directly be used for human consumption arising legitimate criticism from voices referring to countries where protein shortages lead to malnutrition among the population. Jatropha curcas is a tropical oilseed with upcoming popularity for sustainable fuel sourcing. The plant is thought to thrive in semi-arid and arid areas, not just producing oil, but at the same time reclaiming previously eroded land for the local population. For these reasons, annual cultivation of Jatropha curcas is thought to rise over the next decades. After oil is extracted from the seed, the remaining press cake, is currently used as a fertilizer or energy source. This is mostly due to toxic phorbol esters that until recent- ly limited any nutritional applications. In 2011, a method to detoxify Jatropha press cake was developed and paved the way for nutritional research on the resulting detoxified Jatropha curcas kernel meal (JKM) to be launched. JKM offers very high protein content with a balanced amino acid composition suggesting opportunities for usage as a feedstuff in aquaculture diets. JKM further has higher mineral content than comparable oilseeds. However, potential anti-nutritional factors (ANFs) present in the meal could lead to impairment of nutrient availability or other adverse effects. Previous research has already started to evaluate JKM as a protein source for a variety of aquaculture species. This thesis attempts to further identify the potential of JKM as a protein source and assess the effects of JKM on the development of two model cultured teleost species, common carp (Cyprinus carpio) and Nile tilapia (Oreochromis niloticus), as they represent two of the most farmed species, particularly in the tropics. The work comprises growth trials on both species using fishmeal as a subject of replacement in solely fishmeal protein-based diets and on more practical fishmeal/plant protein-based diets. It engages with the effects of phytate, a prominent component of JKM with potential anti-nutritional attributes and commercially available phytase feed supplements to diminish these attributes, as well as oxalate, another plant-specific component with high concentrations in JKM and with limited attention in aquaculture nutrition research. Carp and tilapia showed varying results with different inclusion levels of JKM. For carp 50% fishmeal replacement was possible without losses in growth in diets where fishmeal was the only bulk protein source (Chapter 3.1), Tilapia showed slightly worse growth at a 30% replacement level (Chapter 3.2). A steep decline in growth could be observed when replacing 100% fishmeal with JKM in carp (Chapter 3.1), while tilapia showed no difference at that level compared to 30% replacement (Chapter 3.2). In practical diets, 100% of fishmeal could be replaced by JKM without any adverse effects on growth of carp (Chapter 3.3), while tilapia showed a slight, but significant linear negative correlation with higher inclusion levels of JKM (Chapter 3.4). Phytase addition in tilapia feeds was identified as having no obvious impact on growth in JKM based diets where enough available phosphorus was provided through mineral supplementation (Chapter 4.1). In JKM based diets where available phosphate was not added, phytase addition showed a tendency to increase growth and significantly increased mineral retention and decreased phosphorus effluent contamination (Chapter 4.2). Phytase application through pre-incubating JKM along with citric acid exerted a positive effect of growth on carp when fishmeal protein was replaced by 50% (Chapter 3.1). Phytase was further shown to completely hydrolyze phytate in vitro; however, incomplete hydrolysis was observed in vivo in tilapia (Chapter 4.3). Dietary soluble oxalate added to fishmeal based diets for carp showed better growth parameters, nutrient and mineral retention at inclusion levels 1.5% and higher (Chapter 5.1). For tilapia, a trial could demonstrate adverse effects of oxalate on potassium, calcium, manganese and zinc digestibilities, in this case without negative effects on growth (Chapter 5.2). For both, carp and tilapia, an impact of oxalate on lipid metabolism was evident, lowering body lipid content and blood cholesterol in inclusion levels from 1.5% or higher. JKM can become a valuable alternative to present dietary protein sources in aquaculture feeds. The nutritional attributes of JKM need further research, especially longer-term testing in a commercial scenario and application in commercially produced feeds. Results of this thesis pose a useful addition to previous research and can be referred to for realizing these next steps.
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Health and Health Care Utilization among the Unemployed / Hälsa och vårdutnyttjande bland arbetslösaÅhs, Annika January 2006 (has links)
The number of persons who are not employed has increased in Sweden since the early 1990s. Unemployment has been found to influence health, especially when unemployment rates are low. The extent to which unemployment affects health when unemployment is high is less clear, and this needs to be further studied. To improve health in the population, the health care system should offer equal access to health care according to need. It is important to study whether the employment status hinders the fulfilment of this goal. This thesis is based on four papers: Paper I and II aimed at analysing self-rated health versus mortality risk in relation to employment status, during one period of low unemployment and one period of high unemployment. Paper III and IV assessed the use of medical health care services and unmet care needs among persons who were unemployed or otherwise not employed. The goal was to analyse what health problems lead people to either seek or abstain from seeking care, and what factors encumber or facilitate this process. The overall results indicate that being unemployed or outside the labour force was associated with an excess risk of poor self-rated health, symptoms of depression, mental and physical exhaustion and mortality. The differences in self-rated health between the unemployed and employed were larger when unemployment levels were high, than when they were low. More groups of the unemployed were also afflicted with poor health when unemployment was high. Thus, poor health among the unemployed seems to be a public health problem during high levels of unemployment. Lack of employment was related to abstaining from seeking care, despite perceiving a need for care, and this was related to psychological symptoms. To deal with the needs of the unemployed and others who are outside the labour force it would be useful to develop and implement interventions within the health care system. These should focus on psychological and psychosocial problems. Future research should analyse how to facilitate health-promoting interventions among persons who are not anchored in the labour market.
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Model-based data mining methods for identifying patterns in biomedical and health dataHilton, Ross P. 07 January 2016 (has links)
In this thesis we provide statistical and model-based data mining methods for pattern detection with applications to biomedical and healthcare data sets. In particular, we examine applications in costly acute or chronic disease management. In Chapter II,
we consider nuclear magnetic resonance experiments in which we seek to locate and demix smooth, yet highly localized components in a noisy two-dimensional signal. By using
wavelet-based methods we are able to separate components from the noisy background, as well as from other neighboring components. In Chapter III, we pilot methods for identifying
profiles of patient utilization of the healthcare system from large, highly-sensitive, patient-level data. We combine model-based data mining methods with clustering analysis
in order to extract longitudinal utilization profiles. We transform these profiles into simple visual displays that can inform policy decisions and quantify the potential cost savings of
interventions that improve adherence to recommended care guidelines. In Chapter IV, we propose new methods integrating survival analysis models and clustering analysis to profile
patient-level utilization behaviors while controlling for variations in the population’s demographic and healthcare characteristics and explaining variations in utilization due to different state-based Medicaid programs, as well as access and urbanicity measures.
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An evaluation of degradable protein and nonprotein nitrogen on intake and digestion by Dohne merino sheep fed wheat strawNolte, Joubert van Eeden 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: South Africa, like many other developing countries throughout the world, has a rapidly
growing human population, resulting in a consequent increased demand for food. Ironically,
this increased food supply has to be produced on a smaller area of available agricultural land,
which means that agricultural production processes have to become more efficient.
Furthermore, the majority of the people in these countries are unschooled and poverty is a
common phenomenon. Therefore, animal scientists are faced with the challenge and the
responsibility to provide affordable, high quality food to these people.
One way of reaching this objective is to improve the utilisation of low-quality, high roughage
feedstuffs like crop residues and dry natural grass pastures. In the winter rainfall area of
South Africa alone, about 460 000 ha of wheat straw are annually available. The ruminant
animal has the ability to utilise the relatively unavailable energy (cellulose, hemi-cellulose
and pectin) in the fibre component of these low-quality forages. Unfortunately, various
factors, of which a N deficiency is the pre-dominant one, limit the utilisation of these
feedstuffs. If the ability of the ruminant to utilise low-quality, fibrous energy sources is
improved, these abundantly available and relatively inexpensive crop residues and natural
pastures can be converted into high quality protein food for human consumption. Therefore, in order to rectify the N deficiency caused by these low-quality forages, the
supplemental N requirement to optimise the fermentation and digestive processes of the
ruminant animal has to be determined. The first study was conducted to determine the
supplemental rumen degradable protein (RDP) requirement, to maximise the digestible
organic matter intake (DOMI) of Dohne Merino sheep fed wheat straw. Keeping the high
cost of natural protein supplementation in mind, the purpose of the second study was to
determine the amount of true protein that can be replaced by nonprotein nitrogen (NPN) in
RDP supplements fed to Dohne Merino sheep consuming wheat straw.
In both trials animals had ad libitum access to low-quality wheat straw (3.2% CP;
74.2% NDF) and water. In the first trial, RDP (calsium caseinate: 90% CP; 100% rumen
degradable) was intraruminally administered at 07hOOand 19hOO,at the following levels: 0,
40,80, 120 and 160 gld. Intake, fermentation and digestion were monitored to determine the
RDP requirement to maximise DOM!. Digestible organic matter (OM) intake displayed a
quadratic increase with elevated amounts of RDP (P < .01), and was maximised at an
estimated 3.15 g RDPlkg BW·75 or 11.6% of DOM. Forage OM intake tended to increase
quadratically (P = .15) with higher RDP levels. Microbial nitrogen (MN) flow to the
duodenum and microbial efficiency increased quadratically (P ~ .04) and fluid dilution rate
tended to increase in a quadratic manner (P = .15) with increased RDP supplementation
levels. Rumina! ammonia nitrogen (NH3-N) and total volatile fatty acid (VFA)
concentrations increased linearly (P ~ .07), while rumen pH exhibited a variable response to
increased RDP levels (cubic; P = .08). Increasing RDP supplementation to Dohne Merino
wethers consuming wheat straw, generally enhanced forage utilisation and DOM!.
In the second trial, urea replaced different levels of casein N on an isonitrogenous basis,
ranging from 0 - 100%. Since true protein is much more expensive than urea, the purpose of
this study was to determine the maximum natural protein level that can be replaced by urea in
RDP supplements, without adversely affecting intake and/or fermentation and digestive
processes. The control treatment provided all of the RDP in the form of calcium caseinate
(90% CP; 100% rumen degradable). The percentages of supplemental RDP from urea in the
other treatments were 25, 50, 75 and 100%. The 100% urea treatment was balanced with
maize starch to contain 40% CP and all other treatments received the same amount (150 gld)
of starch. Intake of forage OM showed a weak decreasing trend (linear; P = .16) with increasing urea levels. Ruminal digestibilities of OM and NDF were not affected (P ;;::.:18) by
urea level. Increasing urea levels resulted in linearly reduced total tract OM and NDF
digestibilities (P ~ .10). As a result, DOMI declined (linear; P < .01) with increasing
proportions of urea. Effects of increasing urea proportions on duodenal N flow, microbial
efficiency and fluid dilution rate were minimal. Ruminal NH3-N tended to increase
quadratically with increasing urea levels (P = .l4). Total VFA concentration decreased
linearly (P = .03), while rumen pH increased in a linear manner (P = .08) with increasing
urea proportions. Branched-chain volatile fatty acids (BCVFA's) and valerate decreased
linearly (P ~ .05) with increasing urea levels, while other VFA's and the acetate:propionate
ratio were generally not affected by treatment (P ;;:::.16). It appears as though ruminal and
total tract OM and NDF digestibility criteria, as well as DOMI reached maximum values at
substituting 25% of casein for urea. It is therefore concluded that replacing 25% of casein
with urea in RDP supplements, will maintain effective utilisation of low-quality forages by
sheep. / AFRIKAANSE OPSOMMING: Ontwikkelende lande, insluitend Suid-Afrika, word gekenmerk deur 'n vmmge
bevolkingsaanwas. Dit lei tot 'n verhoogde vraag na voedsel, wat op 'n gevolglik kleinerwordende
beskikbare kommersiële lanbbou-area geproduseer moet word. Die
doeltreffendheid van produksieprosesse in die landbousektor moet dus noodgedwonge
verbeter word. Die oorgrootte meerderheid van die bevolkings in ontwikkelende lande is
ongeletterd en armoede en hongersnood is soms 'n algemene verskynsel. Veekundiges word
dus gekonfronteer met die uitdaging en verantwoordelikheid om bekostigbare, hoë kwaliteit
voedsel aan hierdie mense te voorsien.
Een van die mees doeltreffende metodes om hierdie probleem aan te spreek, is om die
benutting van lae kwaliteit, hoë-vesel voerbronne, bv. oesreste en droë grasweidings te
verhoog. In die winterreënstreek van Suid-Afrika alleen, is 460 000 ha koringstrooi jaarliks
beskikbaar. Herkouers beskik oor die besondere vermoë om die relatief onbeskikbare energie
(sellulose, hemi-sellulose en pektien) in die veselkomponent van hierdie lae kwaliteit voere te
benut. Verskeie faktore, waarvan 'n N-tekort die mees prominente is, beperk egter die
benutting van hierdie voerbronne. Die uitdaging is dus om die herkouer se vermoë om
hierdie voere te benut, te optimaliseer. Sodoende word 'n geredelik beskikbare, onderbenutte
en relatief goedkoop voerbron omgeskakel in hoë kwaliteit proteïen vir menslike gebruik. Die N-aanvullingsbehoefte om die fermentasie- en verteringsprosesse van die herkouerdier te
optimaliseer moet dus bepaal word, sodat die N-tekort in herkouers, wat soortgelyke
weidings benut, reggestel kan word. Gevolglik was die doel met die eerste proef om die
behoefte aan rumen degradeerbare proteïen-(RDP)-aanvulling, vir die maksimum inname van
verteerbare organiese materiaal (VOM) van Dohne Merino skape wat koringstrooi ontvang,
te bepaal. Weens die hoë koste van natuurlike proteïenaanvulling, was die doel met die
tweede proef om die hoeveelheid ware proteïen in RDP-aanvullings, vir Dohne Merino skape
wat koringstrooi ontvang, wat met nie-proteïen stikstof (NPN) vervang kan word, te bepaal.
In beide eksperimente het die diere ad libitum toegang tot koringstrooi (3.2% RP;
74.2% NBV) en water gehad. In die eerste proefis RDP (kalsiumkaseïnaat; 90% RP; 100%
rumen degradeerbaar) teen 07hOOen 19hOOintraruminaal toegedien, teen die volgende peile:
0, 40, 80, 120 en 160 gld. Inname, fermentasie en vertering is gemonitor om die RDP
behoefte vir die maksimum inname van VOM te bepaal. Verteerbare OM-inname het 'n
stygende kwadratiese tendens (P < .01) getoon met verhoogde RDP-peile en het 'n
maksimum bereik by 'n aanvullingspeil van 3.15 g RDPlkg metaboliese liggaamsmassa
(LM·75
) of 11.6% van VOM. Organiese materiaalinname vanaf koringstrooi het geneig om
kwadraties toe te neem (P = .15) met verhoogde RDP-peile. Mikrobiese stikstof-(MN)-vloei
na die duodenum en mikrobiese effektiwiteit het kwadraties toegeneem (P :::;.;04) en vloeistof
deurvloeitempo het 'n neiging vir 'n kwadratiese toename (P = .15) met verhoogde RDPpeile
getoon. Rumen-ammoniakstikstof (NH3-N) en vlugtige vetsuur-(VVS)-konsentrasies
het lineêr toegeneem (P :::;.;07), terwyl rumen pH 'n wisselende reaksie (kubies; P = .08) met
stygende RDP-peile getoon het. Verteerbare OM-inname en benutting van koringstrooi is
verbeter deur stygende peile van RDP aanvulling by Dohne Merino hamels.
In die tweede proef is kaseïen op 'n iso-stikstof basis met verskillende ureumpeile, vanaf
o - 100%, vervang. Omdat ureum baie goedkoper is as natuurlike proteïen, was die doel van
die tweede proef om die hoeveelheid natuurlike proteïen in RDP-aanvullings te bepaal wat
met ureum vervang kan word, sonder om inname, fermentasie en vertering te benadeel. Die
kontrolebehandeling het 100% van die RDP in die vorm van kalsiumkaseïnaat (90% RP;
100% rumen degradeerbaar) voorsien, terwyl ureum in die ander behandelings onderskeidelik
25, 50, 75 en 100% van die kaseïen-N vervang het. Die 100% ureumbehandeling is met
mieliestysel tot 40% RP gebalanseer en dieselfde hoeveelheid stysel (150 gld) is by al die ander behandelings ingesluit, om moontlike effekte van stysel op rumenfermentasie te
elimineer. Organiese materiaalinname vanafkoringstrooi het 'n swak dalende tendens getoon
met stygende ureum insluitingsvlakke (lineêr; P = .16). Rumenverteerbaarheid van OM en
neutraal bestande vesel (NBV) is nie deur die ureumpeil beïnvloed nie (P ;;:: .18).
Toenemende ureumpeile het gelei tot 'n lineêre afname in totale kanaal OM en NBVverteerbaarheid
(P ~ .10). Gevolglik het VOM inname lineêr afgeneem (P < .01) met
stygende ureum insluitingspeile. Die effek van behandeling op duodenale N-vloei,
mikrobiese effektiwiteit en vloeistof deurvloeitempo was minimaal. Rumenammoniakstikstof-(
NH3-N)-konsentrasie het 'n stygende kwadratiese tendens getoon
(P = .14) met toenemende ureum peile. Totale vlugtige vetsuur-(VVS)-konsentrasies het
lineêr gedaal (P = .03), terwyl rumen pH lineêr toegeneem het (P = .08) met stygende ureum
insluitingsvlakke. Vertakte ketting VVS' e en valeriaansuurkonsentrasies het lineêr gedaal
(P ~ .05) met stygende ureumpeile, terwyl die ander VVS' e en die
asynsuur:propioonsuurverhouding oor die algemeen nie deur behandeling beïnvloed N; nie
(P ;;:: .16). Dit blyk asof VOM inname, sowel as rumen- en totale kanaal
verteerbaarheidsmaatstawwe, by 25% vervanging van kaseïen-N met ureum-N 'n maksimum
bereik het. Die gevolgtrekking is gemaak dat die doeltreffende benutting van lae kwaliteit
ruvoere deur skape, gehandhaaf sal word deur 25% van die ware proteïen in RDP-aanvullings
met ureum te vervang.
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Animal performance from natural pastures and the effects of phosphorus supplementationRead, Marion Victoria Pearl 03 1900 (has links)
Thesis (MScAgric) -- Stellenbosch University, 1984. / INTRODUCTION: This study was initiated by the various reports of improved
animal performance resulting from supplementary feeding of grazing ruminants and in this respect,
it may be regarded
as a feasibility study of the ability of the natural pasture at the applied stocking rates, to
supply the animal with its nutrient requirements, since before providing the animal
with supplementary nutrients, it is necessary to identify
those which may possibly limit animal production. The criti= cal test of such a limiting nutrient
would be an improved animal performance, resulting from supplementation of the
nutrient suspected as being limiting, under grazing conditions.
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Comparison of production parameters, gut histology, organ weights, and portion yields of broilers supplemented with Ateli plusTeuchert, Nicole 04 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Antibiotic growth promoters (AGP’s) have been used in feed of production animals to improve
their growth performance and disease resistance. However, there has been an increase in the
presence of antibiotic residue in animal products, as well as an increase in untreatable illnesses
due to antibiotic resistant bacteria. This led to the European Union banning the use of antibiotic
growth promoters, in production animals, in 2006. An alternative to AGP’s is therefore needed in
animal feed in order to maintain performance. Plant extracts and essential oils have gained
much attention, due to their natural antimicrobial, antibacterial, anticoccidial and antioxidant
properties. This study tested the efficiency of Ateli plus®, an oregano plant extract based
product, as a replacement to AGP’s on production parameters, carcass characteristics and
organ and gut health of broilers.
This study consisted of five treatments fed to broilers from hatch till 33 days of age, fed in three
phases; starter, grower and finisher. The treatment diets consisted of a negative control (no
AGP), positive control (AGP), Ateli plus® at 1kg/ton (Ateli plus® min), Ateli plus® at 2kg/ton for
week one followed by 1kg/ton for the remainder of the period (Ateli plus® max), and AGP plus
Ateli plus® max (AGP plus Ateli plus® max). Results from this study show that there was no difference in performance parameters between
treatments. The performance parameters tested included liveability, average daily gain (ADG),
average weekly feed intake, average cumulative feed intake, average weekly live weight,
average cumulative weight gains, feed conversion ratio (FCR), cumulative FCR and the
European production efficiency factor (EPEF). Broiler breast and thigh muscle pH and colour
(L*, a* and b*) reading values were measured, showing a trend for improved L* colour reading
value and ultimate pH, in broilers supplemented with Ateli plus®. This leads to an increase in
water binding capacity and tenderness, therefore resulting in an improvement in meat quality.
No differences were shown for dressing percentage and portion percentages relative to carcass
weight. No significant differences were seen for tibia bone Ca and P content, or tibia bone fat,
moisture or ash percentages. However a significant decrease in tibia bone strength was found
in all broilers supplemented with Ateli plus® diets and the negative control diet, compared to
AGP supplemented broilers. Gut morphology showed no consistent effect of treatment on villi
height or crypt depth of the duodenum, jejunum and ileum. No significant differences between
treatments were found for organ pH or organ weights, except the gizzard, which was heavier for
Ateli plus® max supplemented broilers.
Ateli plus® shows promise on improving meat quality characteristics of broilers, however the
significant decrease in tibia bone strength in Ateli plus® supplemented broilers is a major
concern and needs to be researched further. Ateli plus® acts as a good AGP replacement, as
broiler performance for the Ateli plus® supplemented broilers was maintained, and not decreased, when compared to the AGP supplemented broilers. However, the broilers fed the
negative control diet had performance parameters statistically equal to both the Ateli plus® and
AGP supplemented broilers, as well as no significant differences between organ weights were
found. It can therefore be said that the broilers were raised under good management, and their
optimal environmental conditions. Therefore conclusive effectiveness of Ateli plus® as a
replacement for AGP on broiler performance cannot be reported from this study. / AFRIKAANSE OPSOMMING: Antibiotiese groeistimulante (AGP’s) word gereeld as voerbymiddels vir diere gebruik om groei
en siekte weerstandbiedenheid te verbeter. Die verbod op die gebruik van antibiotika as 'n
groeipromotor in die Europese Unie (sedert 2006) kan toegeskryf word aan die toename in
onbehandelbare siektes as gevolg van weerstandbiedende bakterieë, asook die
teenwoordigheid van residue in die dierlike produkte. Alternatiewe vir AGP’s in dierevoeding
word dus benodig om produksie te handhaaf. Plant ekstrakte en essensiële olies het baie
aandag gekry as gevolg van hul natuurlike antimikrobiese, antibakteriële, antikoksidiese en
antioksidatiewe eienskappe.
'n Studie is gedoen om die doeltreffendheid van Ateli plus® ('n origanum plant ekstrak
gebaseerde produk) op groei produksie parameters, karkaseienskappe, orgaan- en
dermgesondheid te bepaal wanneer Ateli plus® as 'n AGP plaasvervanger in die dieëte van
braaikuikens gebruik word. Gedurende die proef was vyf verskillende diëte/behandelings vir 33
dae vir braaikuikens gevoer. Die behandelings het bestaan uit 'n negatiewe kontrole (geen
AGP), positiewe kontrole (AGP), Ateli plus® teen 1kg/ton (Ateli plus min), Ateli plus® teen
2kg/ton vir die eerste week gevolg deur 1kg/ton vir die res van die tydperk (Ateli plus® max), en
AGP plus Ateli plus® max (AGP plus Ateli plus® max). Resultate van hierdie studie toon dat behandelings nie 'n effek op produksie parameters gehad
het nie. Die groei produksie parameters wat getoets is sluit in oorlewing, gemiddelde daaglikse
toename (GDT), die gemiddelde weeklikse voer-inname, gemiddelde kumulatiewe voerinname,
gemiddelde weeklikse lewendige massa, gemiddelde kumulatiewe gewig toename,
voeromsetverhouding (VOV) en die Europese produksie doeltreffendheid faktor (EPEF). Die
pH en kleur (L*,a* en b* waardes) van die dy- en borsspier is gemeet. Ateli plus® aanvulling in
braaikuiken diëte het 'n tendens getoon vir verbeterde L * en finale pH waardes in die spiere,
wat lei tot 'n toename in waterhouvermoë en sagtheid en dus verbeterde vleiskwaliteit. Geen
verskille tussen behandelings is gevind vir uitslagpersentasie en die massa van porsies
(uitgedruk as persentasie relatief tot karkasgewig) nie. Behandelings het nie 'n effek op die vet,
vog, as persentasies of Ca- en P-inhoud van die tibia gehad nie.
In vergelyking met AGP aangevulde braaikuikens, is 'n beduidende afname in die tibia
breeksterkte van kuikens in die negatiwe kontrole groep en kuikens wat met Ateli plus®
aangevul is, gevind. Spysverteringskanaal morfologie het getoon dat behandeling geen
konsekwente effek op villi hoogte of krip diepte van die duodenum, jejunum en ileum gehad het
nie. Slegs die krop massas van kuikens wat met Ateli plus® max aangevul is, was swaarder in
vergelyking met hoenders in die ander behandelings; verder is geen beduidende verskille
tussen behandelings gevind vir orgaan pH of orgaan gewigte nie.
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Consumptive wildlife utilization as a land-use form in NamibiaErb, Karl Peter 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This study summarizes data for the consumptive wildlife industry in Namibia, both in
terms of resource availability and current utilization and monetary value. Based on
these data a spreadsheet-based cash-flow model is developed to simulate scenarios
and to explore what constitutes the critical parameter. Based on this data synthesis
and modelling, recommendations are made and conclusions drawn.
Chapter one gives an overview of Namibia's economy, with special reference to the
livestock and wildlife industry. The fact that the commercial livestock herd has been
shrinking over the years is pointed out, as well as the stable output achieved through
better management practices. The literature research has shown that wildlife
ranching could be a viable alternative to livestock farming as practised in southern
Africa, especially in the more arid areas with higher rainfall variability.
Chapter two outlines the resource availability, based on the distribution and densities
of the more common species. The occurrence of the rarer species is touched on.
The point is made that it is very difficult to accurately count wildlife over large areas
and that, as elsewhere, Namibia's wildlife at a regional scale is underestimated.
Chapter three documents the consumptive use of wildlife. Trophy hunting, the most
important segment in terms of national income, is discussed together with the live
sale of game, live export of game, venison production and night culling. A
comparison is made between the economic outputs of the wildlife industry versus
that of the commercial cattle industry.
Chapter four covers financial modelling and the economics of the wildlife industry in
Namibia. A spread-sheet based deterministic model is developed to explore the
cash-flow implications of various game ranching options, such as using different
species mixes, owning land of different carrying capacities and offering different
services.
Chapter five addresses policy and legislative issues in relation to the wildlife industry.
Topics such as property rights and exclusive utilization rights, industry representation
and the forming of smart partnerships with primary resource users are covered.
Broad recommendations are made to the Ministry of Environment and Tourism.
Chapter six is used for a concluding synthesis of the previous four chapters. / AFRIKAANSE OPSOMMING: Hierdie studie som die konsumptiewe wildlewe industrie in Namibie op in terme van
van beide beskikbaarheid, huidige verbruik en monetere waarde van hierdie
hulpbron. Gebaseer op hierdie data is 'n kontantvloei model opgestel om
vooruitskouings te simuleer, met betrekking op aanbevelings en gevolgtrekkings.
Hoofstuk een gee 'n oorsig van die Namibiese ekonomie met spesiale verwysing na
die vee- en wildboerdery. Daar word uitgewys dat die gesamentlike kommersiele
veekudde oor die afgelope aantal jare kleiner geword het, terwyl die opbrengs stabiel
gebly het deurdat better bestuurspraktyke toegepas is. Die literatuurstudie het
gewys dat in suider-Afrika, wildlewe-boerdery 'n lewensvatbare alternatief kan wees
vir veeboerdery, veral in die droër streke wat 'n hoër reenval speling toon.
Gebaseer op die verspreiding en digtheid van die meer algemene wild, gee hoofstuk
drie 'n oorsig van die beskikbaarheid van hierdie hulpbronne. Trofeejag, wat die
belangrikste inkomstesektor is, word bespreek, sowel as die lewende verkoop,
uitvoer en nagoes (skiet van diere gedurende die nag vir vleisproduksie) van wild,
asook die wildvleis produksie. Met betrekking tot die ekonomiese uitsette, word 'n
vergelyking gemaak tussen die wildlewe en kommersiele veeboerdery industrie.
Hoofstuk vier dek die finansiele modelering en ekonomiese aspekte van die wildlewe
industrie in Namibie. 'n Rekenaar "spreadsheet" -gebaseerde, deterministiese model
is ontwikkel om die kontantvloei van verskeie opsies van wildlewe boerdery te
verken. Voorbeelde sluit in die gebruik van verskillende spesie samestellings, die
besit van grond met verskillende drakrag vermoëns, asook die aanbiedinge van
verskeie dienste.
Hoofstuk vyf bespreek die beleid en wetgewing met betrekking tot die wildlewe
industrie. Onderwerpe soos eiendomsreg en eksklusiewe benuttingsregte, industrie
verteenwoordiging en die stigting van "smart" vennootskappe met primere hulpbron
verbruikers, word aangespreek. Aanbevelings word aan die Ministerie van
Omgewing en Toerisme gemaak.
Hoofstuk ses behels 'n sintese van die voorafgaande vier hoofstukke.
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Species utilisation preferences and resource potential of miombo woodlands : a case of selected villages in Tabora, TanzaniaMbwambo, Lawrence Richard 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2000. / Full text to be digitised and attached to bibliographic record. / ENGLISH ABSTRACT: Miombo woodland occupies the greater portion of the Zambezian phytoregion where
communities derive products and services for their livelihood. The managers of these
resources have for many years neglected these crucial needs, which has important
implications for silvicultural systems and management interventions. The overall objective of
this study was to document the miombo species utilisation preferences by local communities
in Tabora, Tanzania. This information was obtained using individual interviews and village
meetings. A simple line transect inventory survey was carried out to assess the miombo
resources adjacent to the studied villages.
The villagers in Tabora have knowledge of the importance of their woodland
resources and put different species to different uses, with some overlap where a species has
multiple uses. The surveyed villages differ in the utilisation of miombo resources, where the
choice and quantities used depend on their proximity to urban areas. There is strong
preference for suitable species for building poles and due to scarcity some people now use
mud bricks for house construction. Suitable timber tree species are scarce in the Urumwa
Forest Reserve and now low quality species such as Sterculia quinqueloba are used. For
firewood live trees are cut and dried, however any combustible material is used. Not
surprisingly the community's use priorities differ from the management priorities of the
Forest Department. The use of miombo products for income generation in the studied
villages is influenced by the proximity to urban areas and villagers do not perceive
commercialisation of these products as depriving them of resources. The use of woodlands
for cultural and religious purposes in Tabora, though important to the spiritual wellbeing of
people, has declined over the years. The fact that the villagers choose particular miombo trees
for different purposes is an indication of some kind of local knowledge and management. The
Urumwa Forest Reserve is now an open access resource as villagers have depleted wood
resources adjacent to their settlements. Awareness of the causes of miombo resource
depletion in these villages is positively correlated with the proximity to urban areas and wood
scarcity.
Community participation in management of natural resources is still new in Tabora as
few villagers were aware of the new government management interventions of the Urumwa
woodlands, and awareness seems to be limited largely to males and leaders. There is active
management of indigenous trees protected on farms for various uses and exotic tree-planting
mainly for fruits and shade, is done around homesteads, but with no de jure rights of
ownership. Tree planting in this area is severely hindered by drought, insects and termite
attack to seedlings and this has made people depend entirely on the miombo for their wood
requirements.
The simple wood resource inventory survey carried out in this study has showed that the
Urumwa miombo woodland is heavily utilised. This has resulted in poor tree diameter
distribution and species composition. The smaller tree diameters recorded in the Urumwa
Reserve indicate that the potential of this woodland for timber production is low compared to
other products. The priority products documented in this study form base-line information for
management plans and silvicultural systems suitable for sustainable management and
utilisation of these woodlands in future. / AFRIKAANSE OPSOMMING: Miombo bosveld beslaan die grootste gedeelte van die Zambezi vegetasiestreek
waarin 'n groot menslike bevolking produkte en dienste uit hierdie bioom genereer om 'n
bestaan te maak. Bestuurders van hierdie bronne verwaarloos al jare hierdie kritiese
behoeftes, en dit het belangrike implikasies vir boskundige sisteme en bestuurstussentredes.
Die hoofdoel van hierdie studie was om die miombo spesiesbenutting-voorkeure van plaaslike
gemeenskappe in Tabora, Tanzanië te bepaal. Inligting is bekom deur individuele
onderhoude en dorpsvergaderings. 'n Eenvoudige lyn-transek opname is uitgevoer om die
miombo-bronne langs die bestudeerde dorpies te bepaal.
Die dorpsbewoners in Tabora dra kennis van die belangrikheid van hul bosveld bronne
en gebruik verskillende spesies vir verskillende doele, met oorvleuling waar spesies
meervoudige gebruike het. Die dorpies wat ondersoek is verskil in die benutting van miombo
bronne waar die keuses en kwantiteite wat gebruik word bepaal word deur die nabyheid aan
stedelike gebiede. Daar is 'n sterk voorkeur vir spesies geskik vir boupale en as gevolg van
skaarste van die spesies gebruik sommige inwoners nou klei bakstene vir huiskonstruksie.
Geskikte spesies vir die produksie van hout is skaars in die Urumwa Forest Reserve en lae
kwaliteit spesies soos Sterculia quinqueloba word gebruik. Lewende bome word gekap en
gedroog vir brandhout alhoewel enige brandbare materiaalook gebruik word. Dit is nie
verbasend dat die gemeenskap se gebruiksprioriteite verskil van die bestuurs-prioritiete van
die Departement Bosbou nie. Die gebruik van miombo-produkte vir inkomste-generasie in
die bestudeerde dorpies word beinvloed deur die nabyheid aan stedelike gebiede en
dorpsbewoners beskou nie dat die kommersialisering van sulke produkte hul van hulpbronne
ontneem nie. Die gebruik van bosveld vir kulturele en godsdienstige doeleindes in Tabora,
wat belangrik is vir die geestelike gesondheid van die inwoners, het oor die jare afgeneem.
Die feit dat dorpsbewoners besondere miombo-bome kies vir verskillende gebruike is 'n
aanduiding van 'n mate van plaaslike kennis en bestuur. Die Urumwa Bosreserwe is nou 'n
vrye toegang hulpbron omdat dorpsbewoners houtbronne na aan hul dorpies uitgeput het.
Bewustheid van die oorsake van die uitputting van miombo hulpbronne naby die dorpies is
positief gekorreleerd met die nabyheid aan dorpsgebiede en houtskaarste.
Gemeenskapsdeelname by die bestuur van natuurlike hulpbronne is 'n nuwe konsep in
Tabora omdat min dorpsbewoners bewus is van nuwe bestuursintredes deur die regering by
die Urumwa bosveld en bewustheid blyk beperk te wees tot mans en leiers. Daar is aktiewe
bestuur van inheemse bome wat vir spesefieke gebruike beskerm word op plase en uitheemse
boomaanplantings, hoofsaaklik vir vrugte en skadu, word by huise gemaak. Daar is geen de
jure regte in die geval nie. Boomaanplantings in die gebied word ernstig beperk deur droogte,
insekte en termietaanvalle op saailinge en dit veroorsaak dat mense uitsluitlik op miombo
staat maak vir hul houtbehoeftes.
Die eenvoudige houthulpbron-opname wat in die studie onderneem is het bewys dat
die Urumwa miombo bosveld strafbenut word en dat daar geen balans tussen aanwas en hout
benutting is nie. Dit veroorsaak swak boomdeursnit-verspreiding en spesies samestelling.
Die kleiner boomdeursnitte wat in die Urumwa Bosreserwe aangeteken is dui daarop dat die
potensiaal van hierdie bosveld vir houtproduksie laag is en slegs beperk is tot ander produkte.
Die voorkeur-produkte wat in hierdie studie gedokumenteer is vorm kerninligting vir
bestuursplanne en boskundige sisteme wat geskik sal wees vir die toekomstige volhoubare
bestuur en benutting van hierdie bosvelde.
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