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- Abraham, Maria Celina, et al.
(författare)
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Breed influences on in vitro development of abattoir-derived bovine oocytes
- 2012
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 54
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is a discrepancy in the reproductive performance between different cattle breeds. Using abattoir-derived ovaries and data base information we studied the effects of breed on in vitro fertilization and early embryo development. Methods: The in vitro developmental competence of oocytes from cattle (n = 202) of Swedish Red (SR), Swedish Holstein (SH) and mixed beef breeds was compared, retrospectively tracing donors of abattoir-derived ovaries using a combination of the national animal databases and abattoir information. Age was significantly lower and carcass conformation score was higher in the beef breeds than in the dairy breeds. Cumulus oocyte complexes (n = 1351) were aspirated from abattoir-derived ovaries from animals of known breed (visual inspection confirmed through databases), age (databases), and abattoir information. Oocytes were matured, fertilized (frozen semen from two dairy bulls) and cultured according to conventional protocols. On day 8, blastocysts were graded and the number of nuclei determined. Results: Cleavage rate was not different between the breeds but was significantly different between bulls. The percentage of blastocysts on day 8 was significantly higher when the oocyte donor's breed was beef or SR than SH. There was no significant difference in blastocyst grades or stages between the breeds, but the number of nuclei in day 8 blastocysts was significantly lower in SH compared to the beef. Conclusions: The use of abattoir-derived ovaries from animals whose background is traceable can be a valuable tool for research. Using this approach in the present study, oocyte donor breed was seen to affect early embryo development during in vitro embryo production, which may be a contributing factor to the declining fertility in some dairy breeds seen today.
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| 5. |
- Abraham, Maria Celina, et al.
(författare)
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Testicular length as an indicator of the onset of sperm production in alpacas under Swedish conditions
- 2016
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 58
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Tidskriftsartikel (refereegranskat)abstract
- Background The popularity of alpacas (Vicugna pacos) is increasing in Sweden as well as in other countries; however, knowledge about optimal management practices under Swedish conditions is still limited. The wide age range reported when the onset of puberty can occur, between 1 and 3years of age, makes management decisions difficult and may be influenced by the conditions under which the alpacas are kept. The aim of this study was to find out when Swedish alpacas can be expected to start producing sperm, by using testicular length and body condition score as a more precise indirect indicator than age. Results This study suggests that animals with a testicular length ≥3.8cm would be producing sperm; however, if it is crucial to know that there is no sperm production for management purposes, the threshold level for testicular length used to differentiate between sperm-producing and non-sperm producing animals should be ≤1.6cm instead. If only one variable is considered, testicular length appears to better than age alone to predict sperm production. Body condition score together with testicular length explains the individual onset of puberty and better guide management recommendations. Conclusions Using a combination of these parameters (testicular length, body condition score and age) as a tool for decision making for alpaca husbandry under Swedish conditions is suggested.
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| 6. |
- Blanco Penedo, Isabel, et al.
(författare)
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Challenges and priorities for modelling livestock health and pathogens in the context of climate change
- 2016
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351 .- 1096-0953. ; 151, s. 130-144
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Tidskriftsartikel (refereegranskat)abstract
- Climate change has the potential to impair livestock health, with consequences for animal welfare, productivity, greenhouse gas emissions, and human livelihoods and health. Modelling has an important role in assessing the impacts of climate change on livestock systems and the efficacy of potential adaptation strategies, to support decision making for more efficient, resilient and sustainable production. However, a coherent set of challenges and research priorities for modelling livestock health and pathogens under climate change has not previously been available. To identify such challenges and priorities, researchers from across Europe were engaged in a horizon-scanning study, involving workshop and questionnaire based exercises and focussed literature reviews. Eighteen key challenges were identified and grouped into six categories based on subject-specific and capacity building requirements. Across a number of challenges, the need for inventories relating model types to different applications (e.g. the pathogen species, region, scale of focus and purpose to which they can be applied) was identified, in order to identify gaps in capability in relation to the impacts of climate change on animal health. The need for collaboration and learning across disciplines was highlighted in several challenges, e.g. to better understand and model complex ecological interactions between pathogens, vectors, wildlife hosts and livestock in the context of climate change. Collaboration between socio-economic and biophysical disciplines was seen as important for better engagement with stakeholders and for improved modelling of the costs and benefits of poor livestock health. The need for more comprehensive validation of empirical relationships, for harmonising terminology and measurements, and for building capacity for under-researched nations, systems and health problems indicated the importance of joined up approaches across nations. The challenges and priorities identified can help focus the development of modelling capacity and future research structures in this vital field. Well-funded networks capable of managing the long-term development of shared resources are required in order to create a cohesive modelling community equipped to tackle the complex challenges of climate change.
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| 7. |
- Blanco Penedo, Isabel, et al.
(författare)
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Modeling heat stress under organic dairy farming conditions in warm temperate climates within the Mediterranean basin
- 2020
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Ingår i: Climatic Change. - : Springer Science and Business Media LLC. - 0165-0009 .- 1573-1480. ; 162, s. 1269-1285
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Tidskriftsartikel (refereegranskat)abstract
- We studied the effect of heat stress on milk quality in Spanish organic dairy farms using published milk productivity equations. We collected data from 23 weather stations and 14,424 milk test-days for milk yield and milk fat and protein content for the period July 2011 to June 2013. As an indicator of heat stress, we used the maximum daily temperature-humidity index (THI) from 2 days before the milk test date. We fitted the data using hierarchical regression models stratified by farm, cow parity and monthly test-day milk records. The effect of THI was deemed low on biological costs through milk yield. However, the known negative relationship between milk yield and milk quality (protein and fat content) became even steeper when the THI increased, suggesting a significant negative correlation between heat stress and milk quality. Therefore, although the milk yield of cows in the organic farming systems analyzed appeared resilient to heat stress conditions, milk quality, a major selling point for organic dairy products, was negatively affected. The model presented here could be used to predict the potential impacts of different climate change scenarios on dairy farming, and to delineate adaptation strategies within organic systems.
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- Jönsson, Mari, et al.
(författare)
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Will forest conservation areas protect functionally important diversity of fungi and lichens over time?
- 2017
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Ingår i: Biodiversity and Conservation. - : Springer Science and Business Media LLC. - 0960-3115 .- 1572-9710. ; 26, s. 2547-2567
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Tidskriftsartikel (refereegranskat)abstract
- Incorporating functional values in biodiversity monitoring systems could add novel perspectives of the status of biodiversity in conservation areas. Stable frequencies of large foliose nitrogen-fixing cyanolichens likely have positive effects on the nitrogen budget of forests and provide food, material and shelter for invertebrates, gastropods and birds. Stable volumes of deadwood and frequencies of associated fungi provide an important supporting function for ecosystem services such as nutrient cycling, carbon storage and soil formation. Based on regional monitoring data from boreal old-growth forest nature reserves and key habitats, we tested for changes in the frequency of various functionally important substrates and species over time. We detected significant reductions in the frequency of indicator cyanolichens occurring on deciduous trees already after 10years in key habitats, despite non-significant changes in their host substrates. Frequencies of indicator pendulous lichens Alectoria sarmentosa and Bryoria nadvornikiana had also decreased in key habitats, despite overall stable volumes of large conifer host trees. Lichen reductions were more pronounced in the smaller key habitats compared to the larger formally protected nature reserves, likely due to degrading fragmentation and isolation effects. In contrast to these lichens, the average frequencies of old-growth forest indicator fungi decaying coniferous deadwood and common fungi on deciduous trees (Fomes fomentarius) and coniferous trees (Fomitopsis pinicola) remained unchanged. The studied cyanolichens and fruiting fungi generally had similar extinction rates over 10years, whilst only cyanolichens had substantially lower colonization rates. Amid a severely fragmented landscape, conservation areas seem to struggle in preserving some of the basic old-growth forest values.
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| 10. |
- Jönsson, Mari, et al.
(författare)
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Övervakning av värdefulla skogsbiotoper : en utvärdering av extensivmetoden efter 10 år
- 2015
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Rapport (refereegranskat)abstract
- Mellan åren 2009-2011 genomfördes de första återinventeringarna av de 19 nyckelbiotoper, 17 naturreservat och fyra äldre produktionsskogar i Dalarnas och Gävleborgs län som inventerades tio år tidigare 1998-2002 inom övervakningsprogrammet ”Extensiv övervakning av biotopers innehåll med inriktning mot biologisk mångfald” (Extensivmetoden). I den här rapporten redovisas tillståndet vid återinventeringarna 2009- 2011 samt metodens effektivitet för övervakning och uppföljning av biologisk mångfald i dessa naturreservat, nyckelbiotoper och produktionsbestånd. Den ursprungliga tanken med Extensivmetoden är att inventeringarna ska upprepas vart tionde år för en viss grupp av objekt. Syftet här har varit att svara på (1) vilka förändringar som har skett för enskilda objekt samt en viss grupp av objekt för olika skogliga variabler, indikatorarter och vanliga vedsvampar, (2) hur små/stora genomsnittliga förändringar som kan avläsas med statistisk signifikans för enskilda objekt och en grupp av objekt och (3) vilka förändringar som har skett under 10-årsperioden i de skyddade områdena respektive nyckelbiotoperna jämfört med de äldre produktionsbestånden och ”vanlig” skogsmark baserat på riksskogstaxeringens data?Resultaten visade att mängden substrat, antalet förekomster av indikatorarter och enskilda arter varierar mer än vad som kan förväntas av slumpen mellan olika grupper av inventeringsobjekt. Reservaten var generellt mer strukturellt mångfaldiga och artrika än produktionsbestånden, med mer lövträd, död ved av olika slag och fynd av indikatorarter per hektar. Nyckelbiotoper intog en mellanposition och hade lägre volym av död ved per hektar än naturreservaten. Medelfrekvensen indikatorarter och vanliga vedsvampar var i genomsnitt högre per hektar i naturreservat jämfört med nyckelbiotoper. Lägre medelfrekvenser av vanliga vedsvampar i nyckelbiotoperna kunde till stor del förklaras av en högre frekvens av fnöskticka F. fomentarius i reservaten.Ingen förändring kunde statistiskt säkerställas för någon av de studerade skogliga variablerna, artgrupperna eller arterna i reservaten eller nyckelbiotoperna efter 10 år. Artrikedomen av indikatorarter förblev också opåverkad över tidsperioden. Detta betyder att både skyddade naturreservat och frivilligt avsatta nyckelbiotoper hade upprätthållit en mångfald av skogliga strukturer och arter under den angivna tidsperioden. Den här rapporten är därmed den första empiriska studien som visar att artrikedomen och frekvensen av skogliga indikatorarter och vanliga vedsvampar var oförändrad över tid inom både reservat och nyckelbiotoper. Det är dock viktigt att komma ihåg att styrkeanalyserna påvisade att storleken på förändringarna som kunde påvisas med en god statistisk styrka på ca 80 % varierade för den undersökta variabeln och objektkategorin. Ett urval av 17 naturreservat var tillräckligt för att upptäcka relevanta förändringar på 25-35 % (motsvarande rödlistkategorin sårbar) av den ursprungliga genomsnittliga frekvensen av indikatorarter och vanliga vedsvampar, samt individuellt vanliga svampar som fnöskticka och klibbticka, med 80 % statistisk styrka. Den statistiska styrkan för att upptäcka liknande förändringar från ett urval av 19 nyckelbiotoper var endast 20-40 %. Extensivmetoden hade en sämre precision och styrka för att följa upp förändringar för enskilda arter, speciellt för hänglavar i cirkelprovytor och mer ovanliga arter i bältessegment.Vår bedömning är att Extensivmetoden skulle kunna få en betydande roll för miljöövervakning av värdefulla skogsbiotoper i Sverige. Upprepbarheten är god och det finns i dagsläget väldigt få etablerade miljöövervakningsprogram i skyddsvärda skogar där upprepbarheten har utvärderats på ett liknande långsiktigt sätt. Bristen på långsiktiga övervakningsdata gör det svårt att bedöma Extensivmetodens effektivitet och betydelse i förhållande till annan miljöövervakning. En samordnad och jämförbar nationell och regional långsiktig miljöövervakning av miljökänsliga och viktiga artgrupper som lövträdslevande epifyter och vedlevande svampar saknas för olika skogsbiotoper, men är av stor betydelse för förståelsen av dessa biotopers naturvårdsnytta under framtida skötsel, förvaltning och klimat.
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