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Do German Shepards have less subchondral at the base of the coronoid processus in cases of coronoid disease compared to other breeds?
No full textAlbueleddsdysplasi (AD) er en sekkebetegnelse for utviklingsfeil som rammer albueleddet hos hunder, der medial coronoidsykdom (MCD) forekommer hyppigst. Albueleddsdysplasi beskrives ofte som den vanligste årsaken til frambeinshalthet hos unge hunder av store raser og det anses å ha multifaktorielt opphav med flere teorier om etiologien og patogenesen bak. MCD kan være vanskeligere å diagnostisere enn de andre primærlesjonene, spesielt på røntgen, og diagnosen avhenger mer av sekundærlesjoner som beinpåleiringer og artrose. Det spekuleres i om hvorvidt schæferhundraser har mindre sklerose ved basis av coronoidprosessen ved coronoidsykdom enn andre raser, men dette har ikke vært objektivt vurdert. Formålet med denne fordypningsoppgaven er derfor å se nærmere på denne påstanden.
Resultatene viste at schæferhundraser med MCD generelt hadde lavere grad av sklerose enn andre raser, med signifikant forskjell i flere av undergruppene. Den tydeligste forskjellen ble funnet i hovedanalysen og hos hunder uten artrose, mens enkelte delanalyser med små utvalg hadde lav statistisk styrke. Konklusjonen er at funnene støtter mistanken om at schæferhundraser med MCD kan ha mindre sklerose ved basis av coronoidprosessen enn andre raser, noe som kan ha betydning for diagnostikken av MCD hos schæfere og understreker behovet for rasespesifikke vurderinger ved tolkning av røntgenbilder.Elbow dysplasia (ED), most commonly manifesting as medial coronoid disease (MCD), is a frequent cause of forelimb lameness in young large-breed dogs and is thought to have a multifactorial origin, with several theories on its etiology and pathogenesis. MCD can be more challenging to diagnose than other ED types, especially with radiography, as its diagnosis often relies on secondary lesions like osteophytes and arthrosis. It has been speculated that Swiss and German shepherd dog breeds show less sclerosis at the base of the coronoid process in cases of MCD, although this remains unproven. The aim of this paper is to investigate this claim further.
The results showed that Swiss and German shepherd dogs with MCD had less sclerosis than other breeds. A significant difference was found in several subgroups, most notably in the main analysis including all dogs in the study, and among dogs without arthrosis. The findings support the claim that Swiss and German shepherd dogs with MCD show less sclerosis at the base of the coronoid process compared to other breeds. This can potentially affect how MCD is diagnosed in Swiss and German shepherd dogs and highlights the importance of considering the breed when assessing radiographs.VE
Driftsstrategier og lønnsomhet for sesonglagring av fjernvarme med HT-BTES: En casestudie av Furuset, Oslo
Get PDFEtterspørselen etter kraft forventes å øke frem mot 2050. Kraftproduksjonen i Norge og Norden skal bestå av fornybare kilder, som blant annet består av uregulerbar vind- og solkraft. Sammen med temperaturavhengig forbruk gir dette økte svingninger i kraftsystemet, og økt behov for fleksibilitet. Fjernvarme og lagring av varme kan bidra med nødvendig fleksibilitet både på kort og lang sikt. Sesonglageret som vurderes å installeres på Furuset kan gi fleksibilitet mellom sesonger og år, og avlaste kraftsystemet i perioder med høyt varmebehov og knapp tilgang på kraft. En kvantitativ studie har blitt utført for å vurdere energiutnyttelsen fra og lønnsomheten for lageret av ulike størrelser. Lageret er analysert for størrelsene 100, 200 og 400 borehull, alle med enten en 20 ukers utladning eller en 33 ukers utladning. Det er undersøkt hvordan utladningsvarigheten påvirker virkningsgrad og økonomi. I tillegg er ulike prisscenarioer for elektrisitetspriser testet for å undersøke hvordan prisprofilene påvirker lønnsomhet og optimal drift av lageret.
For å analysere energiutnyttelse og lønnsomhet, både for opprinnelige scenarioer, og for scenarioer i følsomhetsanalysene er energimodellen EnergyPRO brukt sammen med Excel. Følsomhetsanalysene viser hvordan ulike forutsetninger påvirker lønnsomheten. Med forutsetningene i denne studien viser resultatene at et større antall borehull kan være lønnsomt selv om investeringskostnadene øker. Resultatene tyder på at sesonglagring i anlegget på Furuset er avhengig av et høyt prisscenario, hvor lagervarmen erstatter dyr topplast. Resultatene viser videre at optimal drift som er tilpasset varmebehov og prisen på elektrisitet, er det som gir både best lønnsomhet og best energiutnyttelse. Resultatene viser også hvordan sesonglager kan være en kilde til fleksibilitet, men at lønnsomheten av lageret er sensitiv for driftsstrategi og prisprofiler.The demand for electricity is expected to increase towards 2050. Power production in Norway and the Nordic region is planned to rely on renewable sources, including inconsistent wind and solar power. Combined with temperature dependent demand for power and heat, this leads to increased fluctuations in the power system and an increased need for flexibility. District heating and thermal energy storage can provide both short-term and long-term flexibility. The seasonal storage considered at Furuset can provide flexibility over seasons and years and relieve the power system during periods of high heat demand and limited electricity supply. A quantative study has been done to assess the energy utilization and profitability of the storage for different sizes. The storage sizes considered are 100, 200 and 400 boreholes, each with either a 20-week or 33-week discharge period. The impact of discharge duration on efficiency and economy has been examined. In addition, various electricity price scenarios have been tested to evaluate how price profiles affect the profitability and optimal operation of the storage.
To analyze the energy utilization and profitability in the original scenarios and in the sensitivity scenarios, the energy model EnergyPRO has been used in combination with Excel. The sensitivity analyses show how different assumptions influence profitability. Under the assumptions made in this study, the results indicate that a larger number of boreholes may be profitable, even with increased investment costs. The findings suggest that seasonal storage at the Furuset facility depends on a high-price scenario, where stored heat replaces expensive peak load. The results further show that optimal operation, aligned with heat demand and electricity prices, yields both the best profitability and best energy utilization. Additionally, the results demonstrate how seasonal storage can provide flexibility, though the profitability is sensitive to operational strategies and price profiles
The Social Costs and Benefits from Nature Restoration Projects in Norway
Get PDFThis thesis aims to evaluate the social costs and benefits of nature restoration in Norway. It is motivated by the fact that much of nature has deteriorated recently, and there is increased focus on nature restoration globally. In addition, there has recently been more focus on climate goals.
The costs and benefits have been estimated using cost-benefit analysis, benefit transfers, and the mitigation hierarchy. The benefit transfers are conducted carefully with multiple requirements before benefit transfers of the values from ecosystem services are conducted. Data connected to the costs of nature restoration were gathered from the County Governors in Innlandet and Østfold, Buskerud, Oslo and Akershus. When all the data was gathered, Excel and R-studio were used to perform the calculations. After the data was collected, some assumptions were made and analyzed based on different statuses of nature. Multiple sensitivity analyses were conducted to test the results.
The results were estimated for the four steps in the mitigation hierarchy: Avoid, minimize, remediate and offset. Based on the status of nature in each area, the values are different, and all values are estimated in January 2025 NOK. The highest estimates come from avoiding deterioration, with values between 8,8 to 7,6 million kr to keep marshes untouched and approximately 3,6 million kr to keep forests untouched. For the step connected to minimizing the values were lower, which was expected because of the smaller scale. The values varied from 623 000 to 390 000 kr to restore partly deteriorated marshes, and between 103 000 and 81 000 kr for forests. For remediate, which revolves around using an area for another purpose before restoring it. This thesis looks at what would happen if wind power were built and taken down after its lifetime. The values were all negative, ranging from -7,4 to -5,9 million kr. Offset revolves around the restoration of already deteriorated nature and had values between 2,5 to 1,5 million kr for the restoration of marshes and 412 000 to 327 000 kr for forests. This indicates that the values depend on what state nature is in.
The sensitivity analysis shows that the results are relatively robust for both marshes and forests. Restoration of forests in the minimization step in the mitigation hierarchy seems to be the most sensitive to changes in costs and benefits components. The overall results are in line with previous studies, in terms of restoration of marshes having the highest net social benefits among the alternatives considered here
Grønn kontroll i leverandørkjeden: Hvordan Skagerak Energi møter fremtidens bærekraftskrav
Get PDFI takt med skjerpede klimamål og økende regulatoriske etterlevelseskrav, er bærekraft blitt en sentral del av risikostyring og verdiskaping i næringslivet. Energibransjen spiller en nøkkelrolle i overgangen til lavutslippssamfunnet, men er samtidig underlagt strenge krav til rapportering, compliance og styring av komplekse leverandørkjeder. Strengere krav til bærekraftsrapportering og leverandøroppfølging, som blant annet EUs Corporate Sustainability Reporting Directive (CSRD) og den norske åpenhetsloven, har økt behovet for verktøy som gjør det mulig å vurdere risiko i leverandørkjeder på en effektiv og kontrollerbar måte.
I denne masteroppgaven undersøker vi hvordan Skagerak Energi kan balansere økonomisk lønnsomhet med bærekraftige krav i leverandørkjeden. Skagerak Energi er valgt fordi selskapet opererer i en bransje med høy leverandøravhengighet, samtidig som det stilles krav om å bidra til det grønne skiftet. Vi har benyttet en kombinasjon av kvalitative intervjuer og kvantitative analyser, blant annet regresjon, klyngeanalyse og Random Forest, for å analysere sammenhengen mellom ESG-score, finansiell styrke og risiko.
Analysene viser at høyere ESG-score er assosiert med lavere kostnader, og at finansielt sterke selskaper ofte har bedre bærekraftspraksis. Random Forest-modellen oppnådde høy presisjon i å identifisere leverandører med lav ESG-score, spesielt når økonomiske nøkkeltall som EBITDA, nettoresultat og total omsetning ble inkludert. Vi utviklet også et verktøy for ESG-score basert på «Know Your Customer»-prinsippet fra banksektoren. Dette verktøyet kan benyttes for unoterte selskaper uten offentlig ESG-data.
Funnene viser at datadrevne metoder som maskinlæring og ESG-basert rangering gir et godt beslutningsgrunnlag for risikobasert leverandøroppfølging. For Skagerak Energi innebærer dette muligheten til å styrke etterlevelsen av lovkrav og samtidig sikre økonomisk bærekraft. Oppgaven belyser dermed hvordan teknologi og bærekraft kan forenes i moderne leverandørstyring.As global climate goals tighten and regulatory frameworks evolve, sustainability has become a core element of corporate risk management and long-term value creation. The energy sector is uniquely positioned in this transition, both as a driver of green innovation and as a subject of increasing regulatory attention regarding compliance, transparency, and supplier oversight. In light of policy instruments such as the EU’s Corporate Sustainability Reporting Directive (CSRD) and the Norwegian Transparency Act, there is a growing demand for effective and auditable tools to assess supply chain risk.
This thesis explores how the Norwegian energy company Skagerak Energi can balance economic performance with sustainability obligations throughout its supply chain as required by regulatory expectations such as the Norwegian Transparency Act. Given the company’s exposure to complex supply chains and regulatory expectations, it serves as a relevant case for studying data-driven risk assessment. A mixed-method approach was used, combining qualitative interviews with quantitative techniques, regression analysis, cluster analysis, and Random Forest models, to examine the relationship between ESG performance, financial robustness, and risk exposure.
The empirical results indicate that higher ESG scores correlate with lower purchasing costs, and that financial strength is often associated with better ESG profiles. The Random Forest classification model achieved strong predictive accuracy, particularly when financial indicators such as EBITDA, Net Income and Revenue were included. To address gaps in ESG data for unlisted suppliers, a supplementary scoring framework inspired by the banking sectors "Know Your Customer" principles was also developed.
Overall, the findings highlight that machine learning and structured ESG assessment can serve as powerful tools for supplier monitoring and regulatory compliance. For companies like Skagerak Energi, integrating these tools into supplier governance offers a path toward more efficient risk management and sustainable cost management in the supply chain. The study underscores the growing synergy between digital innovation and sustainability in future-oriented supply chain strategies
Seismic performance of a retrofitted RC frame using CLT panels with Asymmetric Friction Dampers: An experimental study
No full textThis study presents an experimental investigation into the seismic performance of a
scaled two-story reinforced concrete (RC) frame retrofitted with externally mounted cross-
laminated timber (CLT) panels and asymmetric friction dampers (the e-CLT system). The
primary objective is to quantify the retrofit’s influence on key dynamic response param-
eters, including interstory drift, torsional amplification, plastic deformation, and energy
dissipation.
A series of shake-table tests were conducted at the LNEC facility in Lisbon, employing
both symmetric and asymmetric panel configurations with varied bolt pretension, under
progressively intensifying L’Aquila 2009 ground motion records (0.04–0.45 g). Sixty-three
displacement and acceleration transducers recorded high-resolution time histories, which
were post-processed using custom Python routines to extract interstory drift ratios, damper
displacements, hysteresis loops, torsional responses, energy-dissipation metrics, etc.
Results demonstrate that the e-CLT retrofit preserved structural integrity across the full
PGA range and, reduces peak interstory drifts by 60-80 % relative to a bare frame base-
line at low to moderate excitations. With the asymmetric panel layout, uneven damper
activation correlated with increased torsional amplification (r = 0.584, p = 0.003), though
its mechanistic origin remains unresolved. Increases in damper-dissipated energy did not
consistently inhibit drift or significantly mitigate plastic damage accumulation.
While the e-CLT system appears to effectively control drift, friction damper engagement
alone does not ensure comprehensive damage mitigation. Further large-scale testing and en-
hanced instrumentation is recommended to clarify the interplay between damper behavior
and global structural response, and to refine design guidelines for optimal energy-dissipative
performanc
En eutrof innsjøs betydning som kilde til atmosfærisk lystgass – med eksempel fra Årungen
Get PDFLystgass, N2O, er en klimagass som kan produseres i vann. Produksjon under anoksiske forhold er avhengig av tilgang på nitrat, og kan begrenses ved lite tilgjengelig nitrogen i økosystemet generelt. Det er mange faktorer som påvirker mengden lysgass som blir produsert i en innsjø, blant annet tilgang på næringsstoffer, temperatur og oksygen. Innsjøens lagdeling eller sjiktning er vesentlig for dannelse av lystgass.
I dette studiet er det gjort feltarbeid i Årungen i Akershus fylke. Årungen er en eutrof innsjø som i mange år har vært preget av mye algeoppblomstring, som blant annet skyldes god tilgang på næringsstoffer som nitrogen og fosfor. Årungen har flere innløpsbekker, og utløpsbekken renner ut i Bunnefjorden som er en del av Indre Oslofjord. Feltarbeidet ble gjennomført hver 14. dag fra 3.juni til 22.oktober 2024. I felt ble det målt både temperatur og oksygen, og det ble tatt to ulike vannprøver på 6 ulike dybder. Videre ble det gjort analyser av vannprøvene på laboratoriet. Det ble gjort analyser for ulike former for nitrogen, herunder lystgass, fosfor, pigmenter og løst organisk karbon.
Av analysene kom det tydelig frem at det var en temperatursjiktning i Årungen sommeren 2024, som resulterte i at hypolimnion var oksygenfri i en lang periode. Ved siste måling i oktober var det full sirkulasjon i vannmassene. I løpet av feltperioden var det store variasjoner i nitrogenmålingene som ble gjort på laboratoriet. Den totale konsentrasjonen av nitrogen sank gjennom store deler av feltperioden, spesielt i nedre halvdel av vannsøylen. For lystgass var det en klar økning i konsentrasjonen gjennom feltperioden. Ved første måling var lystgasskonsentrasjon i hele vannsøylen omtrent 11 g/m2, før den sank til under 5 g/m2 i juli. Videre var konsentrasjonen av lystgass rundt 25 g/m2 i vannsøylen i september.
Produksjonen av lystgass i Årungen sommeren 2024 skjedde hovedsakelig i hypolimnion ved denitrifikasjon. Tilgangen på nitrat i hypolimnion var vesentlig for produksjonen av lystgass, og sommerstagnasjonen sørget for anoksiske forhold. Det ble også produsert lystgass i epilimnion ved nitrifikasjon, og noe lystgass ble sluppet ut av sedimentene. På slutten av måleperioden var lystgasskonsentrasjonen noe lavere enn tidligere, det viser at ved sirkulasjon i vannmassene så kom lystgassen til overflaten og diffunderte videre opp i atmosfæren som klimagass. Lystgass har høyt GWP, og utslipp av gassen kan bidra til nedbrytning av ozonlaget.Nitrous oxide, N2O, is a greenhouse gas that can be produced in water. Production under anoxic conditions is dependent on the availability of nitrate and can be limited by low nitrogen availability in the ecosystem in general. Many factors affect the amount of nitrous oxide produced in a lake, including the availability of nutrients, temperature and oxygen. The stratification of the lake is essential for the formation of nitrous oxide.
In this study, fieldwork was done in lake Årungen in Akershus County, Norway. Årungen is a eutrophic lake that for many years has been characterized by a lot of algae blooms, partly due to good access to nutrients like nitrogen and phosphorus. Årungen has several inlet streams, and one outlet stream that flows into the Bunnefjord, a part of the Inner Oslofjord. The fieldwork was carried out every 14 days from June 3 to October 22, 2024. Both temperature and oxygen were measured in the lake, and two different water samples were taken at six different depths. The water samples were analyzed in the laboratory. Analyses were carried out for various forms of nitrogen, phosphorus, pigments and dissolved organic carbon.
The analyses showed that there was a temperature stratification in Årungen during the summer of 2024, which resulted in the hypolimnion being oxygen-free for a long period. At the last measurement in October, there was full circulation in the water masses. During the study period, there were large variations in the nitrogen measurements made in the laboratory. The total concentration of nitrogen decreased throughout much of the study period, especially in the lower half of the water column. For nitrous oxide, there was an increase in concentration throughout the study period. At the first measurement, the nitrous oxide concentration in the entire water column was approximately 11 g/m2, before dropping to below 5 g/m2 in July. In September the concentration of nitrous oxide was around 25 g/m2.
The production of nitrous oxide in Årungen in the summer of 2024 occurred mainly in hypolimnion by denitrification. The availability of nitrate in the hypolimnion was essential to produce N2O. Summer stagnation ensured anoxic conditions. Some nitrous oxide was also produced in the epilimnion by nitrification of ammonium and some nitrous oxide was released from the sediments. At the end of the measurement period, the concentration of N2O was lower than earlier in the study period, indicating that circulation in the water masses caused the N2O to rise to the surface and diffuse further into the atmosphere as a greenhouse gas. N2O has a high GWP, and emission of gas can contribute to the depletion of the ozone layer
A Climate of Doubt: A Quantitative Study of Populist Radical Right Attitudes and Climate Scepticism and Policy Opposition in the Netherlands
Get PDFAs the world approaches a tipping point in the climate crisis, the populist radical right is becoming the predominant political opponent of climate science and mitigation policies. The recent electoral gains of populist radical right parties worldwide underscore the urgent need to understand the relationship between their ideology and attitudes towards climate change. This thesis investigates which ideological attitudes – related to the populist radical right – are associated with climate scepticism and opposition to climate policy in the Netherlands. Drawing on survey data from the 2023 Dutch Parliamentary Election Study, five hypotheses are tested through a series of OLS and logistic regression models, focusing on two dependent variables: climate scepticism and policy resistance. The findings suggest that ideological attitudes are more closely associated with opposition to climate policy than with climate scepticism. Nativist and gender traditionalist attitudes are most strongly associated with climate policy opposition, while populist attitudes are more closely associated with scepticism toward climate science. Notably, negative financial expectations are not directly associated with climate scepticism or policy opposition but are indirectly linked through populist and nativist attitudes, lending initial support to an ideological interpretation. Drawing on theories of cultural political economy and political science, this thesis argues that populist radical right’s climate opposition is not merely a response to material grievances, but a broader ideological rejection of liberal cosmopolitanism and societal modernisation, and as a political defence of a declining ‘imperial mode of living’. Climate communication should align with prevalent ideological attitudes by highlighting local, tangible climate impacts that threaten familiar ways of life
The High-Risk blaNDM-5/blaCMY-145 Positive Escherichia coli ST167 Clone With Cefiderocol Resistance Associated Mutations Found in a Norwegian Lake, Warning for Potential Community Spread
Get PDFThe discovery of antibiotics revolutionized modern medicine, making it possible to treat infectious diseases and perform complicated medical procedures. However, the extensive use has contributed to the development of antibiotic resistance, which is now one of the leading health treats of this century. The emergence of extended-spectrum β-lactamase (ESBL) and carbapenemase-producing bacteria is of particular concern because we are left with few options for treating these infections. Without precautionary actions, this could potentially become the leading cause of global mortality. The environment has recently been recognized as an important part of the evolution and dissemination of antibiotic-resistant bacteria (ARB) and genes (ARGs). To fully understand the transmission of resistance between the environment, humans and animals, surveillance of the environment is important.
The aim of this study was to investigate the prevalence of ARB and ARGs in freshwater habitats around Oslo. Water was sampled from three different locations and inoculated on ESBL and carbapenem-resistant Enterobacteriaceae (CRE) agar plates to select for resistant bacteria. Pure bacterial cultures were cultivated, and DNA was extracted from 66 isolates and identified through 16S rRNA Sanger sequencing. Fourteen of these isolates were chosen for further analysis. Screening of resistance genes was conducted with Multiplex and Singleplex PCR using β-lactamase specific primers. The selected isolates were also subjected to antibiotic susceptibility testing, and out of these, three were chosen for whole genome sequencing (WGS) with Illumina MiSeq.
Pseudomonas, Stenotrophomonas, Serratia, Duganella, Chryseobacterium, Aeromonas, Acinetobacter and Escherichia were some of the genera identified by 16S rRNA. PCR screening detected ESBL and carbapenemase genes in three Escherichia isolates, and two Serratia isolates. Susceptibility testing revealed high resistance to several β-lactams. WGS identified a high-risk ST167 Escherichia coli clone with YRIN insertion in penicillin binding protein 3 (PBP3), and the presence of blaNDM-5 and blaCMY-145 genes. This gene combination is associated with resistance to the novel antibiotic cefiderocol. Additionally, an enteroaggregative E. coli (EAEC) was identified based on the aggR gene, exhibiting third-generation cephalosporin resistance. The final isolate subjected to WGS was identified as Chryseobacterium rhizosphaerae and harboured several carbapenemase gens. Extensive carbapenem-resistance was also observed with susceptibility testing. These findings indicate the presence of bacteria with resistance to last-resort antibiotics in freshwater habitats near human activity, wildlife and food production areas, rising concerns about potential community spread
Gründeres utfordringer med ansettelser? En eksplorativt studie om feilansettelser; destruktive medarbeidere og person-job misfit
Get PDFI denne masteroppgaven undersøkes og belyses hva som gjør ansettelser krevende for gründere. Studien bygger på kvalitative dybdeintervjuer med 11 norske gründere som har vært med i grunnleggerteamet og bygget selskap – ett eller flere – fra tidlig fase. Formålet har vært å utforske hvordan teammedlemmer velges, forskjellige utfordringer gjennom selskapets faser, spesielt knyttet til feilansettelser og hvordan destruktiv atferd håndteres.
Funnene viser at mange ansettelser skjer i fase 2 – når teamet utvides fra grunnleggerkjernen til tidlig team. Dette skjer under tidspress og med uklare roller, som øker risikoen for jobb–person–misfit og destruktiv atferd. Studien introduserer et sentralt paradoks: Gründeren representerer både risiko og løsning. Manglende struktur og ledelse kan skape grobunn for dysfunksjon, men samtidig har gründeren som både initiativtaker og leder, unik påvirkningskraft på kultur, trygghet og læring.
Funnene viser også stor grad av relasjonell kapital i start-ups, viktigheten av tillit og sårbarheten små team preget av gjensidig avhengighet har for feilansettelser og destruktiv atferd.This master's thesis explores the challenges founders face when making hiring decisions are examined and explored. The study is based on qualitative in-depth interviews with 11 Norwegian founders who have been part of the founding team and built one or more companies from the early stage. The purpose has been to explore how team members are selected, the various challenges across the company’s phases—particularly related to mis-hires—and how destructive behavior is handled.
The findings show that many hiring decisions take place in phase 2, when the team expands beyond the founding core to an early operational team. These hires often occur under time pressure and with unclear role definitions, increasing the risk of person–job misfit and destructive behavior. The study introduces a central paradox: the founder represents both a risk and a solution. A lack of structure and leadership can create fertile ground for dysfunction, yet the founder—as both initiator and leader—has unique influence over culture, psychological safety, and learning.
The findings also reveal a high degree of relational capital in start-ups, highlighting the importance of trust and the vulnerability of small, interdependent teams to mis-hires and destructive dynamics
Funksjon og skjebne til fiber fra havre og bygg i dietter for slaktekylling
Get PDFOats and barley are good alternative energy sources in broiler diets. However, their
fibre fractions, which are typically identified as their limitations, can be a benefit if
properly utilized. This present thesis focuses on insoluble fibre from oats and soluble
fibre from barley. The main objective of this thesis work was to study how oat hull
(OH) inclusion level and particle size affect broiler performance, digestion, and gut
microbiota, focusing on gizzard function in fibre degradation and passage. The impact
of feeding regimen and non-starch polysaccharide degrading enzyme (NSPase)
supplementation on soluble fibre degradation from barley and its effects on digestive
parameters were also studied. This thesis consists of three papers.
The impact of normal oats (with OH) and dehulled oats (without OH) in broiler diets
were examined, focusing on growth performance, gizzard function, and gut
microbiota (Paper I). The hypothesis was that a high inclusion level of normal oats in
pelleted diets negatively affects broiler performance compared to dehulled oats, but
this effect can be mitigated by fine grinding. Birds were fed diets with varying ratios
of normal oats to dehulled oats, ground either finely (2 mm) or coarsely (6 mm), to
assess how fibre content and particle size influence digestion. The diets were
formulated to contain 0, 29.5, 65.0, 96.0 and 114.0 g/kg OH. Increasing OH inclusion
did not affect body weight gain but led to a linear increase in feed conversion ratio
(FCR), suggesting birds compensated for nutrient dilution by increasing feed intake.
Fine grinding improved FCR, whereas coarse grinding enhanced gizzard
development, increasing gizzard dry matter and reducing pH. Additionally, OH
inclusion improved litter quality by increasing excreta dry matter. Despite dietary
changes, caecal short-chain fatty acid production remained unaffected, though lower
indole levels suggest reduced protein fermentation. These findings indicate that
broilers can efficiently handle OH-rich diets, with a larger gizzard capacity facilitating
the passage of fibrous material.
Gizzard functionality and its influence on passage of large OH particles were further
investigated (Paper II). The hypothesis was that coarse OH would be selectively
retained in the gizzard for grinding, but at higher inclusion levels, an increasing
proportion would pass through unground. Only the diets with 0, 65.0 and 114.0 g/kg
OH from Paper I were used for this study. Large fibre particles were selectively
retained in the gizzard, however, at higher OH levels, some unground particles escaped digestion, particularly in diets with coarsely ground OH. Further, to study OH
degradation and flow, birds were sampled at different time points (0, 2, 4, 8, 16h)
after feeding them 114.0 g/kg OH diets for 2h. A significant interaction between time
and screen size was observed for the amount of large particles in the excreta, with
higher levels in 6mm diets compared to 2mm diets, but only at 16 h. Large particles
persisted in the gastrointestinal tract and excreta, with coarser OH resulting in
greater passage of unground material. These results challenge the idea that all
particles must be ground to a critical size before leaving the gizzard, suggesting that
excess coarse fibre may exceed the retention capacity of the gizzard.
Further, the effects of feeding regimen and NSPase supplementation in broilers fed
barley-based diets were explored to investigate soluble fibre degradation and its
impact on digestive parameters (Paper III). The hypothesis was that NSPase
supplementation enhances soluble fibre degradation by increasing the availability of
substrate in high-viscosity barley, leading to increased fermentation in the caeca.
Additionally, its efficiency is further improved with intermittent feeding. Two
pelleted high-viscosity barley-based diets, with and without NSPase
supplementation, were fed to broilers either ad libitum or intermittently. NSPase
supplementation improved fibre degradation, leading to increased soluble sugar
availability in the ileum and higher caecal xylanase activity, suggesting continued NSP
solubilisation and fermentation. Intermittent feeding further enhanced NSPase
effectiveness, as evidenced by higher butyric acid levels in the caeca and a tendency
to reduce branched chain fatty acid concentrations, which are linked to protein
fermentation. These findings indicate that NSPase can enhance nutrient utilization
and gut health, particularly under intermittent feeding conditions.
Overall, this thesis demonstrates that oats and barley can be effectively utilized in
broiler diets at high inclusion levels without compromising performance or health,
provided that fibre levels, particle size, and enzyme supplementation are optimized
alongside efficient feeding strategies. The studies highlight the adaptability of broilers
to fibre-rich diets through gizzard modifications, the selective retention and grinding
limits of the gizzard, and the benefits of intermittent feeding with NSPase in
enhancing digestion and microbial balance. These findings underscore the potential
of fibre fractions, traditionally seen as limiting factors, to improve gut health and feed
efficiency when strategically managed.Havre og bygg er gode alternative energikilder i slaktekyllingfôr. Imidlertid kan fiberfraksjonene deres, som vanligvis identifiseres som deres begrensninger, være en fordel hvis de brukes riktig. Denne oppgaven fokuserer på uløselig fiber fra havre og løselig fiber fra bygg. Hovedmålet med denne oppgaven var å studere hvordan havreskrog (OH) inklusjonsnivå og partikkelstørrelse påvirker slaktekyllings ytelse, fordøyelse og tarmmikrobiota, med fokus på kråsefunksjon i fibernedbrytning og passasje. Effekten av fôringsregime og tilskudd av ikke-stivelse polysakkaridnedbrytende enzym (NSPase) på nedbrytning av løselig fiber fra bygg og dets effekter på fordøyelsesparametere ble også studert. Denne oppgaven består av tre artikler.SUSBROIL (Increased SUStainability through a higher use of barley and oats in BROILer production) ; Felleskjøpet Forutvikling AS ; Nortura SA ; DSM Nutritional Products (UK