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Identificação de sequências homólogas de aquaporinas no genoma de aveia cultivar Barbarasul / Identification of homologous sequences of aquaporins in oat genome cv. BarbarasulSilveira, Carla Ferreira 26 May 2011 (has links)
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Previous issue date: 2011-05-26 / Oats (Avena sativa L.) are a winter cereal used for both humans and livestock, giving
a great importance on the world stage. In the post-genomic era new sequenced
genomes can be used to derive functions of organisms from the knowledge of these
systems. In this work were apply this approach to the analysis of gene family of
aquaporins in oats. The aquaporins are major intrinsic proteins (MIP) that have been
characterized as facilitating the water flow. They are also known as water channels,
glycerol facilitators and aquaglyceroporins, recent data suggest that they facilitate the
movement of other molecular low weight metabolites. The presence of these genes is
importance for the development and adaptation of plants, however, until now there
are not studies reporting the identification of aquaporins in the oat genome. In this
report we identified two sequences identified as potential aquaporins present in the
genome of oat. Considering the number of aquaporin genes present in genome of
rice, Arabidopsis, maize and wheat and the complexity of its polyploid genome, it is
estimated that oats may have around 20 or more copies of these genes in each
genome. Given the growing problems of flooding and drought, the need for cultivation
in areas affected by salinity and the proven role of MIPs on plant response to
stresses related to water availability, the investigations of these genes are essential
in oats too. However a greater number of these genes can be identified in the future,
this study was an important step in its characterization. / A aveia (Avena sativa L.) é um cereal de inverno utilizado tanto para a alimentação
humana quanto animal, apresentando uma grande importância no cenário mundial.
Na era pós-genômica novos genomas sequenciados podem ser utilizados para
inferir funções de organismos a partir do conhecimento de outros sistemas. Neste
trabalho foi aplicada essa abordagem à análise de genes da familia das aquaporinas
em aveia. As aquaporinas são proteínas intrínsecas de membrana (MIP) que têm
sido caracterizadas como facilitadoras do fluxo de água. São também conhecidas
como canais de água, glicerol facilitadores e aquagliceroporinas. Dados recentes
sugerem que elas facilitam a circulação de outros metabólitos de baixo peso
molecular. A presença dos genes que codificam essas proteínas é de suma
importância para o desenvolvimento e adaptação das plantas, contudo, até hoje não
existiam estudos relatando a identificação de genes de aquaporinas no genoma da
aveia. O sequenciamento e caracterização in silico das sequências obtidas neste
trabalho propõem a presença de genes que codificam prováveis aquaporinas. Foram
identificadas duas sequências como prováveis aquaporinas presentes no genoma da
aveia. Considerando o número de genes de aquaporinas presentes no genoma do
arroz, Arabidopsis, milho e trigo e a complexidade de seu genoma poliplóide, estimase
que a aveia possua mais cópias desses genes. Tendo em vista os crescentes
problemas de alagamento e/ou seca, a necessidade de cultivo em áreas afetadas
pela salinidade, e o comprovado papel das MIPs na resposta das plantas a
estresses relacionados com a disponibilidade de água, as investigações desses
genes em aveia são essenciais. Contudo um número maior desses genes poderão
ser identificados e caracterizados, esse estudo representa uma etapa importante
para sua caracterização.
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'n Ondersoek na die invloed van 'n Swart ekonomiese bemagtiging strategie op die waarde van 'n insetverskaffer in die Suid-Afrikaanse landbou omgewingKotze, T. N. (Theunis Nicolaas) 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Agriculture remains an important industry in South Africa. Although primary
agriculture contributes only 4.5% to the Gross Domestic Product (GDP), the
related agrifood industry contributes an additional 9%. Furthermore agriculture is
a major provider of employment, especially in rural areas where more than 50%
of the local community depends on agriculture.
In general Black Economic Empowerment (BEE) is accepted as a precondition to
a stable and prosperous South Africa. As a result thereof various sector plans
have been negotiated and at this stage agriculture is busy with final inputs
towards the Agricultural BEE plan to be finalised in December 2004.
Ownership and management transformation however are difficult for most
farming enterprises as most of them are small family enterprises. Therefore they
will support BEE agricultural input providers to support BEE. According to the
BEE Score Card it will be possible to adhere to BEE requirements without
adhering to ownership and management requirements provided that good scores
are obtained from the other aspects such as skills development, BEE initiatives,
preferred suppliers and other.
The transfer of ownership also has significant financial implications. It is
estimated that R65 billion will be needed to achieve the proposed objectives of
30% agricultural land and 35% of agricultural businesses in the RSA to be
transfered to black people by 2014. However, only R703 million has been spend
on land restitution during the past year and only R933 million budgeted for
2004/2005.
The feasibility of processed oats to be marketed as rolled oats, quick oats and
muesli as such a BEE initiative has been evaluated in this study project as a joint
venture between Agricol and SSK. Agricol (seed company) has cereal type oat varieties whilst Sentraal Suid-Koóperasie (Farmer Cooperative) has good grain
handling infrastructures in the major oat producing areas. This project will
provide both counterparts with the opportunity to integrate vertically, diversify
sources of income (away from primary agriculture), empower previously
disadvantaged individuals in both organisations and to meet BEE objectives.
This study indicates that such a BEE initiative is feasible and offers a very good
return to participants. Extremely high hygene and quality assurance standards of
the processed product, the marketing thereof and market access has been
identified as critical performance areas. At a dehulled percentage of 60% and
price paid for oats of R1000 per ton, 600 ton of the processed oats will have to be
sold annually to ensure a profit of R140 000 per annum.
Subject to the budgeted figures, the project has the potential to realise a
R843000 profit in year 5. The value of the new company based on the
discounted cash flow method, will be R2.7 to R3.9 million. Due to the initial
losses and associated negative cash flows, the value is primarily represented by
the terminal value of the company after 5 years.
Current shareholders require an expected return on capital of 15%. Internal rate
of return for the project is 42% which is much more that the hurdle rate. The
intented BEE initiative therefore definitely adds value to shareholders. Important
people issues like shared vision, values, expectations, trust and commitment
needs to addressed continuously to realise the potential of the project. Strong
and skilled leadership will also play a decisive role as important decisions will
have to be taken continuously. / AFRIKAANSE OPSOMMING: Landbou bly 'n beIangrike industrie in Suid-Afrika en alhoewel primêre-landbou
slegs 4.5% van Bruto Binnelandse Produk (BBP) bydra, word die bydrae van die
landbouverwante agrivoedsel industrie op 'n addisionele 9% beraam. Landbou
is verder 'n belangrike werkverskaffer, veral op die platteland waar meer as die
helfte van die bevolking soms van landbou afhanklik is.
Daar word algemeen aanvaar dat Swart Ekonomiese Bemagtiging (SEB) 'n
voorvereiste tot 'n stabiele en welvarende Suid-Afrika is. In die lig hiervan is
verskeie sektor SEB handveste alreeds onderhandel en die landbousektor is tans
besig om insette te lewer ten einde die landbou handves teen Desember 2004 te
finaliseer.
Aangesien meeste boerdery ondernemings egter klein familie ondernemings is
wat moeilik eienaarskap en bestuurstransformasie kan akkomodeer, sal hulle
SEB landbou inset verskaffers ondersteun om sodoende SEB te ondersteun.
Volgens die SEB telkaart sal dit vir ondernemings moontlik wees om aan SEB
vereistes te voldoen alhoewel daar nie noodwendig aan eienaarskap en
bestuursvereistes voldoen is nie, maar wel goeie tellings op die gebied van
vaardigheidsontwikkeling, SEB inisiatiewe, voorkeurvoorsiening en ander fasette
behaal is.
Die oordrag van eienaarskap het ook omvattende finansiële implikasies. Daar
word beraam dat ongeveer R65 miljard benodig word om die voorgestelde
doelwitte van 30% landbougrond en 35% van landboubesighede in die RSA teen
2014 aan swart mense oor te dra. Hierteenoor is slegs R703 miljoen die
afgelope jaar aan grondhervorming bestee terwyl die begroting vir 2004/2005
R933 miljoen bedra. Die lewensvatbaarheid van verwerkte hawer wat in die vorm van gerolde hawer,
hawermout en muesli bemark sal word, is as SEB inisiatief en gesamentlike
projek tussen Agricol en Sentraal Suid-Koöperasie, in hierdie werkstuk
ondersoek. Agricol (saadmaatskappy) beskik oor ontbytgraan tipe hawer
kultivars en Sentraal Suid-Kooperasie het 'n goeie graanhanterings infrastruktuur
in die hawer produksie gebiede. Die projek sal aan beide medewerkers die
geleentheid bied om vertikaal te integreer, inkomste te diversifiseer (weg van
primêre landbou), voorheen benadeelde individue in beide instansies te bemagtig
en beide instansies help om aan SEB doelwitte te voldoen.
Die studie het aangedui dat so 'n SEB inisitief wel lewensvatbaar is en goeie
opbrengste aan al die deelnemers sal bied. Uitermate hoë higiëne en
kwaliteitstandaarde van die verwerkte produkte tesame met die bemarking en
marktoegang is as belangrike kritiese prestasie areas geïdentifiseer. Teen 'n pit
tot dop verhouding van 60% en gemiddelde aankoopprys van R1000 per ton vir
hawer, moet ongeveer 600 ton verwerkte hawer jaarliks verkoop word om 'n
wins van R140 000 per jaar te verseker.
Gegewe die begrote syfers, het die projek die potensiaal om R843 000 wins in
jaar 5 te genereer. Die waarde van die nuwe maatskappy, gebasseer op die
verdiskonteerde kontantvloei metode, beloop R2.7 tot R3.9 miljoen. As gevolg
van die aanvanklike verliese en gepaardgaande negatiewe kontantvloeie, lê die
waarde van die maatskappy egter hoofsaaklik in die eindwaarde na 5 jaar.
Huidige aandeelhouers se verwagte opbrengs op kapitaal is 15%. Die interne
opbrengskoers van die projek beloop 42% wat dus hoër as die drempelwaarde
is. Die beplande SEB inisiatief voeg dus bepaald waarde toe vir aandeelhouers.
Belangrike mensekwessies soos dieselfde visie, waardes, verwagtinge, vertroue,
verbintenis en toewyding sal baie aandag moet geniet om van die potensiaal 'n
werklikheid te maak. Sterk en bekwame leierskap sal ook 'n deurslaggewende
rol speel aangesien gewigtige besluite voortdurend geneem sal moet word.
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The effect of inoculants on silage fermentation properties and on animal productionMeeske, Robin 12 1900 (has links)
162 leaves printed on single pages, preliminary pages i- vii and numbered pages 1-152. Includes bibliography and abbreviations. / Digitized at 600 dpi grayscale to pdf format (OCR), using a Bizhub 250 Konica Minolta Scanner. / Thesis (PhD(Agric))--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Maize, forage sorghum, lucerne, oats, barley and triticale are the most common silage crops in
South Africa, while tropical grasses like Eragrostis curvula and Digitaria eriantha are ensiled
to a lesser extent. The aim of this study was to determine the effect of adding a lactic acid
bacterial inoculant to E. curvula, D. eriantha, lucerne, forage sorghum, maize and oat silage.
The effect of the addition of a lactic acid bacterial inoculant when ensiling E. curvula on the
fermentation dynamics during ensiling and the aerobic stability of the silage was determined. The
addition of the lactic acid bacterial inoculant to E. curvula at ensiling resulted in a more rapid
lowering in pH and improved preservation. Inoculated silage had a higher lactic acid content, less
protein breakdown and a lower butyric acid content compared to that of the control silage. Both
silages were stable when exposed to air for five days.
Digitaria eriantha was ensiled, with or without the addition of a lactic acid bacterial inoculant
containing Lactobacillus plantarum. Streptococcus faecium and Pediococcus acidilactici
together with the enzymes, cellulase, hemicellulase and amylase. The addition of the inoculant
resulted in a more rapid drop in pH, a higher level of lactic acid, an increase in the number of
lactic acid bacteria, less protein breakdown and lower numbers of enterobacteria, clostridial
spores, yeast and mould compared to the control silage. Digitaria eriantha hay, control and
inoculated silage diets were fed to 24 Merino rams (n = 8 per treatment) to determine intake and
digestibility. The intake of diets consisting of 90.9% D. eriantha hay, control silage or inoculated
silage, differed significantly (p<0.05) at 1395, 1540 and 1848 g DM/day, respectively. The in vivo organic matter digestibility (glkg) of D. eriantha hay, untreated silage and inoculated silage
diets was 561, 546, 574, respectively. The addition of the bacterial inoculant when ensiling D.eriantha resulted in better preservation, improved aerobic stability, as well as a higher in vivo
organic matter digestibility and intake of D. eriantha silage.
The addition of an inoculant or molasses to lucerne (Medicago sativa), ensiled in laboratory silos
was investigated. The addition of the additives resulted in an increased preservation rate as
indicated by a more rapid lowering of pH, a faster rate of lactic acid production and less protein
breakdown compared to control silage. The inoculant was more effective than the molasses in
improving the rate of preservation. The aerobic stability of lucerne silage was not affected by
inoculation or the addition of molasses. The addition of an inoculant to wilted big bale lucerne
silage was studied. The inoculant improved silage quality as indicated by a lower pH, higher
lactic acid content, lower ammonia nitrogen content and lower level of butyric acid in inoculated
silage compared to the control lucerne silage. The composition of big round bale lucerne silage
differed markedly from that of lucerne ensiled in laboratory silos as the former had a higher pH,
ammonia nitrogen, butyric acid and acetic acid content and a lower lactic content.
Whole crop forage sorghum cultivar FS2 was harvested at the late bloom (20.7% DM) and soft
dough (28.9% DM) stages of maturity and ensiled in laboratory silos with the addition
of commercial silage inoculants. At both stages of maturity the inoculants caused a more rapid rate
of pH decline and a higher amount of lactic acid production. All the silages were well preserved.
Silages of the sorghum ensiled at the late bloom stage with all treatments were stable after 5 days
of aerobic exposure, whereas sorghum ensiled at the soft dough stage with the addition of the
inoculants deteriorated upon aerobic exposure. It is concluded that addition of lactic acid
bacterial inoculants to mature sorghum at ensiling might impair the aerobic stability of the silage.
The yield, nutritional value and production potential of silage made from twenty one maize
hybrids was compared. It was concluded that maize hybrids did differ in metabolizable energy
content, rate of digestion, predicted intake and predicted milk production potential. The content
of NDF and ADF did not differ between the maize hybrids used in this study and could therefore
not be used to predict nutritional value or production potential.
Maize was harvested at the hard dough stage and ensiled with or without the addition of a lactic
acid bacterial inoculant in laboratory silos and in 210 litre drums. The adding of the inoculant
to maize at ensiling did not result in a more rapid drop in pH and higher levels of lactic acid. The
intake and growth of South African Mutton Merino lambs fed inoculated and untreated maize
silage diets was determined. The average daily gain of lambs fed a diet consisting of either 60%
control or inoculated maize silage over a growth period of 60 days was 239 ± 26 and 255 ± 44
g/day, respectively. Although the laboratory study showed very little effect of adding a lactic acid bacterial inoculant to maize at ensiling, lambs tended to consume more of the inoculated silage.
In the second study the effect of the addition of a lactic acid bacterial inoculant with an enzyme
to maize at ensiling on the fermentation dynamics during ensiling, aerobic stability of the silage,
the intake, milk production and milk composition of Jersey cows fed maize silage diets was
determined. The inoculant did not result in a more rapid lowering of the pH or a more rapid
lactic acid production compared to untreated maize silage made in laboratory silos. Both the
control and inoculated maize silages were well preserved. The addition of the inoculant to maize
at ensiling improved the palatability, intake and the aerobic stability of maize silage compared
to the untreated control maize silage. Milk production, milk composition, live weight and
condition score of Jersey cows was not significantly affected by the addition of the inoculant to
maize silage.
The effect of the addition of an enzyme containing lactic acid bacterial inoculant to big bale
oat (Avena sativa, cv Cederberg) silage on silage composition, silage intake, milk production and
milk composition of Jersey cows was determined. The crop was cut at the bloom stage, wilted
and ensiled in big round bales. The inoculant, Sil-All, was applied during the baling process on
half of the bales. Silages were fed to Jersey cows in an intake and milk production study. Both
the control and inoculated oat silages were well preserved. The inoculated oat silage had a lower
level of butyric acid than the control oat silage. Cows fed the inoculated oat silage produced
more (P=O.05) milk (17.7 kg/day) than cows fed the control oat silage (16.7 kg/day). The
addition of a lactic acid bacterial inoculant to big bale oat silage improved silage composition
and animal performance.
This study clearly showed that the composition of silages made in bunker silos under
commercial farm conditions differ largely from that of silages made in small scale laboratory
silos. When the effect of silage additives on aerobic stability of silage is determined the
evaluation should include studies on large scale bunker silages. Evaluation of silage additives
should include intake and animal production studies. / AFRIKAANSE OPSOMMING: Mielies, voersorghum, lusem, hawer, gars en korog word algemeen as kuilvoer gewasse benut
terwyl tropiese grasse soos Eragrostis curvula en Digitaria eriantha tot 'n mindere mate
ingekuil word. Die doel van hierdie studie was om die invloed van 'n melksuurbakterieseinokulant
op E. curvula-, D. eriantha-, lusem-, voersorghum-, mielie- en hawerkuilvoer te
bepaal.
Die invloed van 'n melksuurbakteriese-inokulant op die fermentasiedinamika en die aerobiese
stabiliteit van E. curvula-kuilvoer is bepaal. Die toediening van die melksuurbakterieseinokulant
tot E. curvula tydens inkuiling het 'n vinniger tempo van pH daling en beter
preservering tot gevolg gehad in vergelyking met kontrole kuilvoer. Inokulant behandelde
kuilvoer het 'n hoer melksuurinhoud, minder protei'en afbraak en 'n laer bottersuurinhoud as
kontrole kuilvoer gehad. Beide kuilvoere was stabiel tydens blootstelling aan lug vir vyf dae.
Digitaria eriantha is ingekuil met ofsonder die toediening van 'n melksuurbakteriese-inokulant
wat Lactobacillus plantarum. Streptococcus faecium en Pediococcus acidilactici sowel as die
ensieme, sellulase, hemisellulase and amilase bevat het. Die inokulant het 'n vinniger tempo van
pH-daling, hoer vlakke van melksuur en melksuurbakterie, minder protei'en afbraak en laer
getalle van enterobakterie, klostridiale spore, giste and swamme in vergelyking met die kontrole
tot gevolg gehad. Digitaria eriantha hooi, kontrole kuilvoer en gei'nokuleerde kuilvoer diete is
aan 24 Merino ramme (n = 8 per behandeling) gevoer vir bepaling van inname en
verteerbaarheid. Die inname van diete wat uit 90.9% D. eriantha hooi, kontrole kuilvoer of
gei'nokuleerde kuilvoer bestaan het, het betekenisvol (p<0.05) verskil en was 1395, 1540 en 1848
gDM/dag, respektiewelik. Die in vivo organiesemateriaal verteerbaarheid (gIkg) vanD. eriantha
hooi, kontrole kuilvoer en geYnokuleerde kuilvoer was 561, 546, 574, respektiewelik. Die
toediening van die bakteriese-inokulant tydens inkuiling vanD. eriantha het beter preservering,
verbeterde aerobiese stabiliteit asook 'n hoer in vivo organiesemateriaal verteerbaarheid van D.
eriantha kuilvoer tot gevolg gehad.
Die effek van toediening van 'n melksuurbakteriese-inokulant en van molasse tot lusem
(Medicago sativa) ingekuil in laboratoriumsilos is ondersoek. Die inokulant toediening en
molasse toediening het die tempo van preservering versnel, die pH het vinniger gedaal, melksuur
is teen 'n hoer tempo geproduseer en minder proteYen afbraak het plaasgevind in vergelyking met
die kontrole kuilvoer. Die tempo van preservering is meer effektief deur toediening van die
inokulant verhoog as deur die toediening van molasse. Die aerobiese stabiliteit van
lusernkuilvoer is nie beYnvloed deur die toediening van inokulant ofmolasse nie. Die effek van
die toediening van 'n melksuurbakteriese-inokulant tot groot rondebaal lusernkuilvoer is
ondersoek. Die inokulant het die kwaliteit van die kuilvoer verbeter en het 'n laer pH, hoer
melksuur, laer ammoniak stikstofen laer bottersuurinhoud in rondebaallusernkuilvoer tot gevolg
gehad in vergelyking met kontrole kuilvoer. Groot rondebaallusernkuilvoer het grootliks verskil
van lusernkuilvoer wat in laboratoriumsilos ingekuil is. Die rondebaal kuilvoer het 'n hoer pH,
hoer ammoniak-stikstof-, bottersuur- en asynsuurinhoud en 'n laer melksuurinhoud gehad as
laboratorium lusernkuilvoer.
Voersorghum kultivar FS2 is op die laat blom (20.7% DM) en op die sagte deeg (28.9% DM)
stadium met die byvoeging van melksuurbakteriese-inokulante ingekuil in laboratoriumsilos.
Toediening van beide inokulante tot sorghum hetop beide die inkuilstadiums gelei tot 'n vinniger
tempo van pHdaling en meer melksuurproduksie. Aile kuilvoere insluitend die kontrole kuilvoer
was goed gepreserveer. Kontrole sowel geYnokuleerde sorghumkuilvoer ingekuil op die laat
blomstadium was stabiel tydens aerobiese blootstelling vir 5 dae. Sorghumkuilvoer ingekuil op
die sagtedeegstadium met die byvoeging van inokulante was onstabiel tydens aerobiese
blootstelling. Die toediening van melksuurbakteriese-inokulante tot sorghum wat op die
sagtedeegstadium ingekuil word kan aerobiese stabiliteit van die kuilvoer grootliks benadeel.
Die opbrengs, voedingswaarde en produksiepotensiaal van kuilvoer gemaak van 21 mielie
hibriede is vergelyk. Verskille in metaboliseerbare energie inhoud, tempo van vertering,
voorspelde inname en voorspelde melkproduksie het tussen mielie hibriede voorgekom. Die
neutraalbestandevesel- en suurbestandeveselinhoud het nie verskil tussen hibriede nie en
derhalwe kon dit nie gebruik word om voedingswaarde ofproduksiepotensiaal te beraam rue. Mielies is op die hardedeegstadium met of sonder die toediening van 'n melksuurbakterieseinokulant
in laboratoriumsilos en 210 liter dromme ingekui!. Die toediening van die inokulant
het geen invloed op tempo van pH-daling ofproduksie van melksuur gehad nie. Die inname en
groei van SA Vleismerino lammers wat 'n dieet bestaande uit 60% kontrole of inokulant
behandelde mieliekuilvoer ontvang het, is bepaa!. Die gemiddelde daaglikse toename van
lammers was 239 ± 26 and 255 ± 44 g/dag vir die kontrole en inokulant mieliekuilvoer dieet
respektiewelik. Alhoewel die laboratoriumstudie weinig verskille tussen die kontrole en die
geYnokuleerde mieliekuilvoer getoon het, het lammers geneig om meer van die geYnokuleerde
mieliekuilvoer in te neem. In die tweede studie met mieliekuilvoer is die effek van toediening
van 'n melksuurbakteriese-inokulant met ensieme, op die ferrnentasiedinamika tydens inkuiling,
die aerobiese stabiliteit van mieliekuilvoer asook die inname, melkproduksie en
melksamestelling van Jersey koeie bepaa!. Die inokulant het nie die tempo van pH daling en
produksie van melksuurverhoog nie en beide kontrole en geYnokuleerde mieliekuilvoerwas goed
gepreserveer. Die toediening van die inokulant tot mieliekuilvoer het die smaaklikheid, inname
en die aerobiese stabiliteit van mieliekuilvoer verhoog in vergeiyking met kontrole
mieliekuilvoer. Melkproduksie, melksamestelling, liggaamsmassa en kondisiepunt van Jersey
koeie is nie betekenisvol beYnvloed deur die toediening van die inokulant tot mieliekuilvoer nie.
Die effek van die toediening van 'n ensiem bevattende melksuurbakteriese-inokulant tot groot
rondebaal hawer (Avena sativa, cv Cederberg) kuilvoer op die samestelling van kuilvoer,
kuilvoerinname, melkproduksie en melksamestelling van Jersey koeie is bepaa!. Die gewas is
gesny op die blomstadium, verwelk en as rondebaalkuilvoer gepreserveer. Die inokulant, Sil-All,
is tydens die baalproses toegedien op die helfte van die bale. Kuilvoere is aan Jersey koeie gevoer
in 'n inname en melkproduksiestudie. Beide die kontrole en geYnokuleerde hawerkuilvoer was
goed gepreserveer. Die bottersuurinhoud van geYnokuleerde hawerkuilvoer was laer as die van
die kontrole hawerkuilvoer. Koeie wat geYnokuleerde hawerkuilvoer gevoer is het meer (P=0.05)
melk (17.7 kg/dag) geproduseer as koeie wat kontrole hawerkuilvoer ontvang het (16.7 kg/dag).
Die toediening van 'n melksuurbakteriese-inokulant het kuilvoer kwaliteit en diereproduksie
verbeter.
Hierdie studie wys duidelike verskille uit tussen kuilvoer wat in bunkersilos onder kommersiele
toestande ingekuil is, en kuilvoer wat in laboratoriumsilos gemaak is. Wanneer die effek van
kuilvoerbymiddels op die aerobiese stabiliteit van kuilvoer bepaal word behoort finale evaluasie
gedoen te word op kuilvoer gemaak in bunkersilos soos onder plaastoestande plaasvind.
Evaluasie van kuilvoerbymiddels behoort inname en diereproduksiestudies in te sluit.
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Dinâmica do nitrogênio na cultura do milho (Zea mays L.), em cultivo sucessivo com aveia preta (Avena strigosa), sob implantação do sistema plantio direto / Nitrogen dynamics in maize (Zea Mays L) and black oats (Avena srigosa) successive cropping under the introduction of the no-tillage systemFernandes, Flavia Carvalho Silva 21 February 2006 (has links)
O presente trabalho foi desenvolvido na área experimental da ESALQ-USP, localizada no município de Piracicaba/SP, em um Latossolo Vermelho Amarelo, textura areno-argiloso. O experimento teve como objetivo estudar a dinâmica do N no sistema solo-planta da cultura do milho, sob implantação do sistema plantio direto, e, pela técnica do 15N, avaliar a lixiviação de nitrato à profundidade de 0,80 m, a eficiência de utilização do N e o efeito residual do fertilizante nas culturas subseqüentes. O projeto envolveu dois cultivos de milho e um de aveia preta, cultivada na entressafra. O delineamento experimental foi o de blocos casualizados (3x2), com 4 repetições. Os tratamentos consistiram de doses de nitrogênio, na forma de sulfato de amônio (60, 120 e 180 kg ha-1 de N) e uma testemunha, além dos parcelamentos (30 kg ha-1 de N na semeadura e o restante em cobertura; 60 kg ha-1 de N na semeadura e o restante em cobertura). A aplicação de sulfato de amônio enriquecido com 15N foi feita, na dose de 120 kg ha-1 de N, em subparcelas, previamente definidas, apenas no primeiro cultivo do milho. Foram feitas as seguintes avaliações: densidade de fluxo de água e de nitrato na profundidade de 0,80 m do solo (dose de 120 kg ha-1 de N); massa de 100 grãos; massa de matéria seca; teor de N; rendimento de grãos de milho; átomos % 15N nas plantas e solo; fração do N fertilizante na solução do solo na profundidade de 0,80 m, e no perfil do solo; balanço do N na sucessão de culturas; efeito residual do N fertilizante (aplicado no primeiro cultivo de milho) na aveia e no segundo cultivo de milho. Pelos resultados obtidos, concluiu-se que: a) a perda de nitrato total por lixiviação, a 0,80 m de profundidade, no 1º cultivo de milho, na dose de 120 kg ha-1 de N, foi de aproximadamente 96 e 68 kg ha-1, para os parcelamentos com 60 kg ha-1 e 30 kg ha-1 de N na semeadura, respectivamente, dos quais apenas 3 e 1 kg ha-1 foram provenientes do fertilizante nitrogenado; b) na dose 120 kg ha-1 de N, o tratamento com maior quantidade de N aplicado na semeadura (60 kg ha-1), no cultivo de milho do ano agrícola 2003/2004, proporcionou um maior aproveitamento do N do fertilizante (65%), em relação ao tratamento com a dose de 30 kg ha-1 na semeadura (45%) e que, para esse ano, a recuperação do N fertilizante pelo solo, na camada 0-0,80 m, para ambos os tratamentos, 60-60 e 30-90 kg ha-1, foi de 40 e 49%, respectivamente; c) Ainda referindo-se aos tratamentos 60-60 e 30-90 kg ha-1, do N remanescente do sulfato de amônio (120 kg ha-1), aplicado no primeiro ano agrícola (efeito residual), 3,72 e 1,79% foram utilizados pela aveia preta e 2,84 e 2,06% pelo milho cultivado no ano subseqüente (2004/2005), permanecendo no solo (camada 0-0,80 m), 30,19 e 33,47% após o cultivo de aveia preta e 16,79 e 17,91% após o segundo cultivo de milho, respectivamente, para os referidos tratamentos. / The general objective of this work was to study the dynamics of nitrogen in the soil-plant system of two maize crops with a black oats one in between, introducing the no-tillage system. Besides, fertilizing the first maize crop with 15N enriched nitrogen fertilizer, it was also objective of this work to assess the total and the derived from fertilizer nitrate leached at the depth of 0.8 m, the nitrogen use efficiency by the crops and the residual effect of the labeled nitrogen fertilizer. The experiment was carried in the experimental areas of ESALQ-USP in the country of Piracicaba (SP), in a yellow red latossol, sandy-loamy texture. The first maize crop was in 2003/2004 and the second one in 2004/2005. The experimental design was randomized blocks (3 x 2), with four replications. Treatments consisted of nitrogen (as ammonium sulphate) levels (60, 120 and 180 kg ha-1 of nitrogen) and the control, besides the splittings (30 and 60 kg ha-1 of nitrogen in the sowing and the rest in covering). The fertilization with 15N enriched ammonium sulphate in the first maize crop was made only for the level of 120 kg ha-1 of nitrogen, in subplots previously defined. The following measurements were carried out: soil-water and nitrate flux densities at the depth of 0.8 m (120 kg ha-1 of N); weight of 100 grains; weight of plant dry matter; nitrogen content; grain yield; total nitrogen; plant nitrogen use efficiency; fraction of the applied nitrogen in the soil solution at the depth of 0.8 m and in the soil profile; nitrogen balance in the crops succession; nitrogen residual effect in the black oat and the second maize crop. From the results, it could be concluded that: a) the leaching losses of total N, at the depth of 0,80 m, in the first maize crop, at the fertilization level of 120 kg ha-1 of N, were of 96 and 68 kg ha-1 for the splittings 60 and 30 kg ha-1 of N at sowing, respectively, from which only 3 and 1 kg ha-1 were derived from the nitrogen fertilizer; b) at the N fertilization level of 120 kg ha-1, the treatment with higher amount of applied N at sowing (60 kg ha-1) of the first maize crop (2003/2004) led to a higher plant N fertilizer recovery (65%) than the 30 kg ha-1of applied N at the sowing treatment (45%) and that, at the end of this crop cycle, the N fertilizer recovery by the 0-0,80 m soil layer, for 60-60 and 30-90 kg ha-1 treatments, were 40 and 49%, respectively; c) still for treatments 60-60 and 30-90 kg ha-1, from the total N applied in the first maize crop (120 kg ha-1), 3.72 and 1.79% were used by the black oats and 2.84 and 2.06% by the second maize crop, remaining in the soil (0-0.8 m layer), 30.19 and 33.47% after the black oats crop and 16.79 and 17.91% after the second maize crop, respectively for 60-60 and 30-90 kg ha-1 of N treatments.
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The effects of chlormequat chloride and ethephon on selected small grain cereals in South Africa.Ramburan, Sanesh January 2006 (has links)
Lodging poses a serious limitation to successful economic production of small grain
cereals and can lead to extensive yield and quality losses. Plant growth regulators
(PGR's) that reduce plant height and lodging have been employed in management
systems in Europe and the United States, however, these compounds have not been
evaluated on commercial cultivars of wheat, barley and oats in South Africa. Current
recommendations to reduce lodging include limiting N inputs, seeding rates and
critical irrigations, all of which may also limit yield potential and grain quality. The
objectives of this study were to assess the effects of two common stem-elongation-inhibiting
PGR's (chlormequat chloride and ethephon) on the growth, development,
and agronomic characteristics of wheat, barley and oats. The aim of the study was
to introduce an additional component of intensive cereal management in the form of
PGR's, and to allow producers to implement intensive production practices without
incurring losses due to lodging.
Field trials were conducted with each of the three cereal crops in the 2003 and 2004
seasons at Vaalharts and Bethlehem. The PGR's were applied separately and in
combination with each other to lodging-tolerant and -susceptible cultivars (wheat and
oats) at different stages of development (tillering, elongation, flag leaf stage). The
PGR's were also tested in combination with different levels of N (barley) applied at
the haulm elongation stage, the flag leaf stage, or both. The PGR chlormequat
produced negligible effects on plant height, lodging, yield, or quality components in
all of the tested cultivars . Ethephon and the PGR combination successfully reduced
plant height (by 120 to 150mm) and lodging (by 25 to 94%) when applied to the
lodging susceptible cultivars of wheat and oats at the flag leaf stage or as a split
application to the barley cultivar "Puma" (plant height and lodging reduced by 180 to
230mm and 83 to 92% respectively). Effects on grain yield were variable, ranging
from occasional reductions (by 3 t ha(-1) and improvements (by 1 t ha(-1) with the
barley, and no effects with the wheat and oats. Wheat quality parameters such as
protein content and hectolitre mass were improved by 2 and 4% respectively.
However, the nature of the responses was highly dependent on the times of
application with later applications producing the greatest positive effects on quality,
yield and lodging reductions. Additionally, ethephon and the PGR combination
allowed higher levels of N to be employed without increases in lodging of barley.
Generally, ethephon and the PGR combination applied at the flag leaf stage of
growth are suitable anti-lodging tools for small grain cereal production and should be
employed as an insurance measure against lodging in intensive management
systems. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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Dinâmica do nitrogênio na cultura do milho (Zea mays L.), em cultivo sucessivo com aveia preta (Avena strigosa), sob implantação do sistema plantio direto / Nitrogen dynamics in maize (Zea Mays L) and black oats (Avena srigosa) successive cropping under the introduction of the no-tillage systemFlavia Carvalho Silva Fernandes 21 February 2006 (has links)
O presente trabalho foi desenvolvido na área experimental da ESALQ-USP, localizada no município de Piracicaba/SP, em um Latossolo Vermelho Amarelo, textura areno-argiloso. O experimento teve como objetivo estudar a dinâmica do N no sistema solo-planta da cultura do milho, sob implantação do sistema plantio direto, e, pela técnica do 15N, avaliar a lixiviação de nitrato à profundidade de 0,80 m, a eficiência de utilização do N e o efeito residual do fertilizante nas culturas subseqüentes. O projeto envolveu dois cultivos de milho e um de aveia preta, cultivada na entressafra. O delineamento experimental foi o de blocos casualizados (3x2), com 4 repetições. Os tratamentos consistiram de doses de nitrogênio, na forma de sulfato de amônio (60, 120 e 180 kg ha-1 de N) e uma testemunha, além dos parcelamentos (30 kg ha-1 de N na semeadura e o restante em cobertura; 60 kg ha-1 de N na semeadura e o restante em cobertura). A aplicação de sulfato de amônio enriquecido com 15N foi feita, na dose de 120 kg ha-1 de N, em subparcelas, previamente definidas, apenas no primeiro cultivo do milho. Foram feitas as seguintes avaliações: densidade de fluxo de água e de nitrato na profundidade de 0,80 m do solo (dose de 120 kg ha-1 de N); massa de 100 grãos; massa de matéria seca; teor de N; rendimento de grãos de milho; átomos % 15N nas plantas e solo; fração do N fertilizante na solução do solo na profundidade de 0,80 m, e no perfil do solo; balanço do N na sucessão de culturas; efeito residual do N fertilizante (aplicado no primeiro cultivo de milho) na aveia e no segundo cultivo de milho. Pelos resultados obtidos, concluiu-se que: a) a perda de nitrato total por lixiviação, a 0,80 m de profundidade, no 1º cultivo de milho, na dose de 120 kg ha-1 de N, foi de aproximadamente 96 e 68 kg ha-1, para os parcelamentos com 60 kg ha-1 e 30 kg ha-1 de N na semeadura, respectivamente, dos quais apenas 3 e 1 kg ha-1 foram provenientes do fertilizante nitrogenado; b) na dose 120 kg ha-1 de N, o tratamento com maior quantidade de N aplicado na semeadura (60 kg ha-1), no cultivo de milho do ano agrícola 2003/2004, proporcionou um maior aproveitamento do N do fertilizante (65%), em relação ao tratamento com a dose de 30 kg ha-1 na semeadura (45%) e que, para esse ano, a recuperação do N fertilizante pelo solo, na camada 0-0,80 m, para ambos os tratamentos, 60-60 e 30-90 kg ha-1, foi de 40 e 49%, respectivamente; c) Ainda referindo-se aos tratamentos 60-60 e 30-90 kg ha-1, do N remanescente do sulfato de amônio (120 kg ha-1), aplicado no primeiro ano agrícola (efeito residual), 3,72 e 1,79% foram utilizados pela aveia preta e 2,84 e 2,06% pelo milho cultivado no ano subseqüente (2004/2005), permanecendo no solo (camada 0-0,80 m), 30,19 e 33,47% após o cultivo de aveia preta e 16,79 e 17,91% após o segundo cultivo de milho, respectivamente, para os referidos tratamentos. / The general objective of this work was to study the dynamics of nitrogen in the soil-plant system of two maize crops with a black oats one in between, introducing the no-tillage system. Besides, fertilizing the first maize crop with 15N enriched nitrogen fertilizer, it was also objective of this work to assess the total and the derived from fertilizer nitrate leached at the depth of 0.8 m, the nitrogen use efficiency by the crops and the residual effect of the labeled nitrogen fertilizer. The experiment was carried in the experimental areas of ESALQ-USP in the country of Piracicaba (SP), in a yellow red latossol, sandy-loamy texture. The first maize crop was in 2003/2004 and the second one in 2004/2005. The experimental design was randomized blocks (3 x 2), with four replications. Treatments consisted of nitrogen (as ammonium sulphate) levels (60, 120 and 180 kg ha-1 of nitrogen) and the control, besides the splittings (30 and 60 kg ha-1 of nitrogen in the sowing and the rest in covering). The fertilization with 15N enriched ammonium sulphate in the first maize crop was made only for the level of 120 kg ha-1 of nitrogen, in subplots previously defined. The following measurements were carried out: soil-water and nitrate flux densities at the depth of 0.8 m (120 kg ha-1 of N); weight of 100 grains; weight of plant dry matter; nitrogen content; grain yield; total nitrogen; plant nitrogen use efficiency; fraction of the applied nitrogen in the soil solution at the depth of 0.8 m and in the soil profile; nitrogen balance in the crops succession; nitrogen residual effect in the black oat and the second maize crop. From the results, it could be concluded that: a) the leaching losses of total N, at the depth of 0,80 m, in the first maize crop, at the fertilization level of 120 kg ha-1 of N, were of 96 and 68 kg ha-1 for the splittings 60 and 30 kg ha-1 of N at sowing, respectively, from which only 3 and 1 kg ha-1 were derived from the nitrogen fertilizer; b) at the N fertilization level of 120 kg ha-1, the treatment with higher amount of applied N at sowing (60 kg ha-1) of the first maize crop (2003/2004) led to a higher plant N fertilizer recovery (65%) than the 30 kg ha-1of applied N at the sowing treatment (45%) and that, at the end of this crop cycle, the N fertilizer recovery by the 0-0,80 m soil layer, for 60-60 and 30-90 kg ha-1 treatments, were 40 and 49%, respectively; c) still for treatments 60-60 and 30-90 kg ha-1, from the total N applied in the first maize crop (120 kg ha-1), 3.72 and 1.79% were used by the black oats and 2.84 and 2.06% by the second maize crop, remaining in the soil (0-0.8 m layer), 30.19 and 33.47% after the black oats crop and 16.79 and 17.91% after the second maize crop, respectively for 60-60 and 30-90 kg ha-1 of N treatments.
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Kritické hodnocení potenciálu bílkovin sklizňových produktů vybraných plodin z hlediska jejich uplatnění v potravinářských a biotechnologických aplikacích / Critical evaluation of potential of harvested product proteins in selected crops from perspective of their use in food and biotechnological applicationsBUCKOVÁ, Pavlína January 2013 (has links)
This diploma thesis deals with plant proteins. Literary review discusses the properties of the major proteins in selected agricultural crops (wheat, barley, oats, corn, peas, soybeans, canola, potato, Jerusalem artichoke) and their use in food, diet, biotechnology and other industries. The diploma thesis was also assessing the potential production of proteins in these crops on the basis of literature and available statistical data. Data is organized into tables and graphs
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RECRIA DE FÊMEAS DE CORTE PARA ACASALAMENTO AOS 18 MESES DE IDADE / REARING BEEF FEMALE TO BREEDING AT 18 MONTHS OF AGEMacari, Stefani 13 December 2005 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / It was evaluated the performance of beef heifers on grazing receiving different levels of supplement: 0,0; 0,3; 0,6 and 0,9% of live weight (LW), in black oats (Avena strigosa Schreb.) plus Italian ryegrass (Lolium multiflorum Lam.) pasture and exclusively in natural pasture engaged by Annoni grass (Eragrostis planna Nees) after the end of the cycle of these forages. On cultivated pasture it was evaluated the botanic composition and the diurnal ingestive behavior of beef heifers. The supplement utilized was a commercial ration (14% CP; 18,8% NDF; 78,2% TDN) daily supplied at 2 pm. The studied variables were the average daily gain (ADG), body condition (BC), stocking rate (SR), weight gain per area (WGA), total forage on offer (TFO), height, live weight:height relation at 12 and 18 month of age and efficiency of transformation of forage in animal product. On the diurnal ingestive behavior were determined: grazing time, rumination, idle, trough permanence, biting rate and bite weight, in four dates. In cultivated pasture the ADG did not differ between animals that received different levels of supplement and it was bigger to supplemented animals. At 12 month of age the BC, SR, WGA, TFO and height of the animals did not differ between the supplement levels. On supplemented animals it was necessary 8.8 kg of DM of grass to produce 1 kg of live weight. The supply of supplement for heifers in grazing of oats and ryegrass interfere in a positive way on life weight, body condition and life weight: height relation of these animals at 18 months of age. The supplement levels affected partially the diurnal ingestive behavior of animals, reducing grazing time, increasing idle time, interfering on trough permanence time, biting rate and bite weight (P<0.05). The rumination time was not affected by supplement levels (P>0.05). The botanic and structural composition of pasture is influenced by supplement levels utilized and it is related with the cycle of forages production (P>0.05). / Foi avaliado o desempenho de bezerras de corte em pastejo recebendo diferentes níveis de suplemento: 0,0; 0,3; 0,6 e 0,9% do peso vivo (PV), em pastagem de aveia (Avena strigosa Schreb.) mais azevém (Lolium multiflorum Lam.) e exclusivamente em campo nativo ocupado por capim Annoni (Eragrostis plana Nees), após o final do ciclo destas forrageiras. Na pastagem cultivada foi avaliada a composição botânica e o comportamento ingestivo diurno de bezerras de corte. O suplemento utilizado foi uma ração comercial (14% PB; 18,8% FDN; 78,2% NDT), fornecida diariamente às 14:00 h. As variáveis estudadas foram ganho médio diário (GMD), condição corporal (CC), carga animal (CA), produção animal por hectare (GPA), oferta de forragem total (OFT), altura, relação peso vivo:altura aos 12 e 18 meses de idade, e eficiência de transformação de Kg de forragem em produto animal. No comportamento ingestivo diurno foram determinados: tempo de pastejo, ruminação, ócio, permanência no cocho, taxa de bocada e peso de bocado, em quatro datas. Em pastagem cultivada o GMD não diferiu entre animais que receberam diferentes níveis de suplemento e foi maior para animais suplementados. Aos 12 meses de idade a CC, CA, GPA, OFT e altura dos animais não diferiram entre níveis de suplemento. Nos animais suplementados foram necessários 8,8 kg de MS do pasto para produzir 1 kg de peso vivo. O fornecimento de suplemento para novilhas em pastejo em aveia e azevém interfere de forma positiva no peso vivo, CC e relação peso vivo:altura destes animais aos 18 meses de idade. Níveis de suplemento afetaram parcialmente o comportamento ingestivo diurno dos animais, reduzindo o tempo de pastejo, aumentando o tempo de ócio, interferindo no tempo de permanência no cocho, na taxa de bocada e peso do bocado (P<0,05). Tempo de ruminação não foi afetado pelos níveis de suplemento (P>0,05). A composição botânica e estrutural da pastagem é influenciada pelos níveis de suplemento utilizados e está relacionada com o ciclo de produção das forrageiras.
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Innate immunity of human intestinal epithelium in childhood celiac disease : influences from celiac disease associated bacteria and dietary oatsPietz, Grzegorz January 2017 (has links)
Background & Aims: Celiac disease (CD) is a chronic inflammatory small-bowel enteropathy caused by permanent intolerance to gliadin in wheat gluten, and related proteins in ray and barley. It is disputed whether CD patients tolerate oats. The only treatment of CD is lifelong gluten-free diet (GFD). Only individuals that carry the HLA-DQ2 and/or DQ8 alleles, and eat gluten can develop CD. Dysbiosis in the gut microbiota is a suggested risk factor for CD. T cells in small intestinal mucosa, including intraepithelial lymphocytes (IELs), are known to be important in the pathogenesis of CD. In contrast, the role of intestinal epithelial cells (IECs) is poorly understood. In this thesis we investigated the role of IECs in the immune pathology of CD from duodenal mucosa of children with CD, clinical controls and treated CD. We also investigated the role of CD associated bacteria and oats supplemented GFD on the mucosal immune system. Results: A new CD-associated bacterium, Prevotella jejuni, was isolated and characterized. It is a saccharolytic and proteolytic anaerobe. More than 25 defense-related genes, including IRF1, SPINK4, ITLN1, OAS2, CIITA, HLA-DMB, HLA-DOB, PSMB9, TAP1, BTN3A1, and CX3CL1, were upregulated in IECs in active CD. In two in vitro models for intestinal epithelium, small intestine enteroids and T84 polarized tight monolayers, we showed that 70% of these genes were upregulated by interferon (IFN)-γ via the IRF1 pathway. IRF1 was also upregulated by the CD-associated bacteria P. jejuni and Actinomyces gravenitzii. IECs expressed the NLRP6/8 inflammasome yielding CASP1 and biologically active interleukin (IL)-18, which induces IFN-γ in IELs. P. jejuni bound the intestinal epithelial cell lines T84, Caco2, HT29, and INT407, while Lachnoanaerobaculum umeaense preferentially bound Caco2. P. jejuni caused decreased transepithelial resistance over tight monolayers, while L. umeaense caused an increase. P. jejuni upregulated mRNAs for the detoxification molecules CYP1A1, CYP1A2, CYP1B1, and TIPARP, the chemokines CX3CL1, CXCL1, and CXCL10, the sialyltranserase ST3GAL4, and the inflammation promoting protein S100A3 in tight monolayers. L. umeaense upregulated the chemokines CCL20 and CXCL10, and down-regulated TLR2. In a randomized, double-blinded intervention trial comparing two study-groups, standard GFD and oat-containing GFD, we found that mRNAs for several immune effector molecules and tight junction proteins were only reduced in patients receiving GFD, but not in a substantial fraction of patients on GFD with oats. The down-regulatory cytokines IL-10 and TGF-β1, the cytotoxicity-activating NK-receptors NKG2C and NKG2E, and the tight junction protein claudin-4 remained elevated in the study group on GFD with oats. Conclusions: IECs are far from inactive in CD. A key factor in the epithelial reaction in CD appears to be over-expression of IRF1 in IECs. Dual activation of IRF1 and IRF1-regulated genes, both directly by P. jejuni and indirectly by IFN-γ via the IL-18-inflammasome, would drastically enhance the inflammatory response and lead to the pathological situation seen in active CD. P. jejuni harms the intestinal epithelium, i.e., it is a likely risk factor for CD, while L. umeaense strengthen barrier function and local immunity, possibly acting as a protective. A fraction of CD patients should avoid oats in the diet. / Doctoral thesis
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Fusarium species in grains : dry matter losses, mycotoxin contamination and control strategies using ozone and chemical compoundsMylona, Kalliopi January 2012 (has links)
This Project identified the relationships between storage conditions, dry matter losses (DMLs) caused by Fusarium species in cereal grains and mycotoxin contamination and assessed novel control strategies for post-harvest grain management including chemical control and ozone. F. graminearum, F. verticillioides and F. langsethiae were inoculated on wheat, maize and oats and stored under environmental conditions where marginal to optimum spoilage and mycotoxin contamination can occur. DMLs were calculated from the CO2 produced and were significantly correlated with deoxynivalenol (DON), zearalenone (ZEA), fumonisins (FUMs) and T-2 and HT-2 toxins respectively. Mycotoxin levels in wheat and maize exceeded the EU legislative limits with 0.9-1% DMLs. Therefore, CO2 monitoring during storage can indicate the level of contamination in a stored batch. Using CO2 production data at different water activity (aw) and temperature conditions, the environmental regimes at which F. langsethiae can grow and contaminate oats with T-2 and HT-2 toxins were identified for the first time. Five acids were examined in vitro and little effect was observed on Fusarium growth, in the aqueous form, while the effect on mycotoxin production varied. Dissolved in ethanol, adipic, fumaric and ferulic acids inhibited fungal growth and controlled DON and FUMs, but T-2 toxin was stimulated by the ethanol. Two garlic essential oils, propyl-propylthiosulfinate (PTS) and propyl propylthiosulfonate (PTSO) were studied for the first time. In vitro, 200 ppm reduced fungal growth (50-100%) and mycotoxin production by >90%. The efficacy was species-dependent. In naturally contaminated oats of 0.93 aw stored for 20 days, 16 ppm PTSO reduced T-2 and HT-2 toxins by 66% and ochratoxin A (OTA) by 88%, while 200 ppm PTS reduced OTA by 95%. In wheat, 100 ppm PTS reduced DON and ZEA and 300 ppm PTS reduced fumonisins by 40-80%. PTSO:PTS (1:1) at 400 and 600 ppm was very effective against DON and ZEA in wheat of 0.92 aw. Ozone (O3) exposure at 200 ppm for 30 min delayed Fusarium spore germination on media of 0.98 aw and inhibited germination at 0.94 aw. O3 was more effective against fungal spores than mycelium and little effect was observed on growing cultures. In vitro, mycotoxin production after exposure depended on the stage of life of the fungi. O3 reduced fungal populations in grains. Mycotoxin production in wet grains treated with 100-200 ppm O3 for 60 min and stored for up to 30 days was reduced or completely inhibited, depending on the species and the exposure system. Simultaneous drying of the grain due to the O3 passage was observed.
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