Parasitism and phenotypic change in colonial hosts

Changes in host phenotype are often attributed to manipulation that enables parasites to complete trophic transmission cycles. We characterized changes in host phenotype in a colonial host-endoparasite system that lacks trophic transmission (the freshwater bryozoan Fredericella sultana and myxozoan parasite Tetracapsuloides bryosalmonae). We show that parasitism exerts opposing phenotypic effects at the colony and module levels. Thus, overt infection (the development of infectious spores in the host body cavity) was linked to a reduction in colony size and growth rate, while colony modules exhibited a form of gigantism. Larger modules may support larger parasite sacs and increase metabolite availability to the parasite. Host metabolic rates were lower in overtly infected relative to uninfected hosts that were not investing in propagule production. This suggests a role for direct resource competition and active parasite manipulation (castration) in driving the expression of the infected phenotype. The malformed offspring (statoblasts) of infected colonies had greatly reduced hatching success. Coupled with the severe reduction in statoblast production this suggests that vertical transmission is rare in overtly infected modules. We show that although the parasite can occasionally infect statoblasts during overt infections, no infections were detected in the surviving mature offspring, suggesting that during overt infections, horizontal transmission incurs a trade-off with vertical transmissio

Allocation methods in the life cycle assessment of food

Elintarvikkeiden tuotannon ja kulutuksen aikaiset ympäristövaikutukset ovat tiedettävästi merkittävät, mistä syystä on tärkeää että niiden vaikutuksia selvitetään ja niistä viestitään. Elinkaariarviointi on sovelias menetelmä määritettäessä tuotteiden, kuten elintarvikkeiden ympäristövaikutuksia. Sitä käytetään muun muassa poliittisen päätöksenteon pohjalla, yritysten strategisessa suunnittelussa ja viestittäessä tuotteiden ympäristövaikutuksista. Elinkaariarviointia käytetään nykyään aktiivisesti: esimerkiksi Suomessa on laskettu ja viestitty viimeisen vuoden aikana muutamien elintarvikkeiden hiilijalanjäljet, jotka perustuvat elinkaariarviointiin. Elinkaariarvioinnin metodologiaa on kehitetty viimeisinä vuosikymmeninä, mutta kaikista metodologian vaiheiden yksityiskohdista ei ole päästy yhteisymmärrykseen. Merkittävä metodologinen haaste on allokointitilanne, missä tulee määrittää kuinka tuotejärjestelmässä syntyvät syötteet ja tuotokset, kuten kasvihuonekaasupäästöt, jaetaan tarkasteltavalle tuotteelle ja tuotejärjestelmässä samanaikaisesti tuotetuille rinnakkaistuotteille. Esimerkiksi jos elinkaariarvioinnissa tarkasteltava tuote on maito, tulee määrittää kuinka maitokarjatilalla muodostuvat syötteet ja tuotokset jaetaan tilalla tuotettavan naudanlihan ja raakamaidon välillä, ja edelleen raakamaitoa prosessoitaessa tulee määrittää kuinka meijerin syötteet ja tuotokset jaetaan maidon ja muiden tehtaassa syntyvien maitoperäisten tuotteiden välillä. Tutkielma tarkastelee allokointiongelmaa elintarvikkeiden elinkaariarvioinneissa, sekä esittää ja vertailee eri allokointimenettelyjen ja -ohjeiden heikkouksia ja vahvuuksia kirjallisuuskatsauksessa ja suomalaiselle kasvatetulle kirjolohelle tehdyssä case-tarkastelussa. Tutkielmassa selvitettiin, että allokointimenettelyn valinta vaikuttaa merkittävästi tuotteelle laskettuihin ympäristövaikutuksiin. Laskettiin esimerkiksi, että kirjolohifileen tuotannon ilmastovaikutukset ja rehevöittävät päästöt vesiin voivat jopa puolittua tai kaksinkertaistua riippuen valitusta allokointimenettelystä. Eri allokointimenettelyjä tunnistettiin useita, joihin lukeutuvat tavat välttää allokointitilanne ja ratkaista se jotain allokointiperustetta käyttäen, eli jakamalla tuotejärjestelmässä syötteet ja tuotokset esimerkiksi tuotteiden hintojen perusteella. Elintarvikkeiden elinkaariarviointien yhdenmukaistamisen edistämiseksi ja subjektiivisten valintojen vähentämiseksi pidettiin tärkeänä, että allokointimenettelyjen valintaa ohjataan. Tarkasteltujen nykyisten elinkaariarviointiohjeiden allokointisuosituksien ei kuitenkaan nähty tukevan yhdenmukaisia allokointimenettelyjä, sillä ohjeet tarjoavat toisistaan poikkeavia suosituksia. Ne eivät ole myöskään kovin tarkkoja allokointiohjeissaan mahdollistaen lopulta lähes minkä tahansa allokointimenettelyn. Yksityiskohtaisemmille ohjeille vaikuttaisikin olevan tarvetta, mikä tarkoittaa, että allokointimenettelyjen soveltuvuudesta eri elintarvikkeiden allokointitilanteissa on syytä keskustella ja sopia. Lisäksi epävarmuuksien vallitessa viestinnässä tulisi olla varovainen ja ympäristövaikutusten tarkkojen arvojen viestimisen sijasta tulisi harkita karkeampaa tapaa ilmaista tulokset, kuten esittämällä eri allokointimenettelyillä saatujen tuloksien vaihteluvälit.The environmental impacts of food production and consumption are substantial, and therefore, it’s important that their impacts are investigated and communicated. Life cycle assessment (LCA) is one promising method to assess the environmental impacts of products, like food products. It’s a process to assess products' environmental impacts through their life-cycle, and it’s used, for example, in policy making, companies’ strategic decision making and when communicating products’ environmental impacts. LCA is used actively nowadays, for example, over the past year few Finnish food companies have decided to calculate and communicate their products’ carbon footprints using LCA. LCA methodology has clearly developed during the past decades. However, there isn’t a shared view on all of the methodological issues. In fact, one essential methodological challenge is allocation situation. In allocation situation all inputs and outputs, such as, green house gas emissions produced in the product system are to be distributed between the studied product and its co-products. For instance, when the studied product is milk it should be determined how the inputs and outputs produced in the dairy cattle farm are to be divided between the farm’s products: beef and raw milk. Furthermore, in the dairy factory it needs to be decided how the inputs and outputs are to be divided between the further processed milk and other dairy products produced in the factory. The aim of the thesis is to investigate the allocation situations in the LCAs of food, as well as, to present, compare and find weaknesses and strengths of different ways of handling allocation situations and ways of guiding them. This is done in a literature study and in a LCA case-study made for Finnish farmed rainbow trout. It was calculated that the choice of how to handle the allocation situation has a major impact on the environmental impacts directed to the product under investigation. For example, climate change impacts and eutrophication of water bodies caused by production of a trout fillet can halve or double depending on the choice of the allocation method. Several different allocation methods were indentified, including ways to avoid allocation and ways to allocate the inputs and outputs, for instance, on the basis of the products' prices. To improve the harmonization of food LCAs and to reduce subjectivity it is important that there is guidance when choosing the allocation method. However, the existing LCA guides investigated don’t give enough support for the allocation situations. They provide divergent instructions and recommendations; they aren’t very specific in the allocation instructions and they allow choosing almost any allocation method, and therefore there is clear need for more specific instructions. Thus, it is evident that there is need to discuss and agree on the suitability of allocation methods to be used in LCAs of different food products. Also, because of the existing uncertainty one should be really careful when communicating exact environmental impacts, instead, one should consider presenting environmental impacts in a more coarse scale, for example, by presenting the scale of the results when using different allocation methods

Critical review of allocation rules : the case of Finnish rainbow trout

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Characterisation of polymorphic microsatellite loci for the bryozoan Fredericella sultana, the primary host of the causative agent of salmonid proliferative kidney disease

0000-0001-7279-715X© Springer Science+Business Media Dordrecht 2014. The attached document is the authors' final accepted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

Waterbird-Mediated Dispersal and Freshwater Biodiversity: General Insights From Bryozoans

Freshwater environments are fragmented and heterogeneous in space and time. Long term persistence thus necessitates at least occasional dispersal of aquatic organisms to locate suitable habitats. However, the insubstantial movements of many require zoochory—hitchhiking a ride with more mobile animals. We review evidence for waterbird-mediated zoochory of freshwater bryozoans, a group that provides an excellent model for addressing this issue. The feasibility of long distance transport by waterbirds of bryozoan propagules (statoblasts) is evaluated in relation to statoblast resistance to extreme conditions and waterbird gut retention times, flight durations and distances. We highlight genetic evidence for colonization following waterbird-mediated transport. The consequences of zoochory for biodiversity are manifold. Taxa that release statoblasts show lower levels of genetic differentiation, genetic divergence and haplotype diversity than those whose statoblasts are retained in situ (hence less available for zoochory). Zoochory may also disseminate pathogens and parasites when infected host stages are transported. Such co-dispersal may explain some disease distributions and is supported by viability of infected statoblasts. Zoochory can also be expected to influence local and regional population and community dynamics, food web structure and stability, and organismal distributions, and abundances. Finally, zoochory may influence host-parasite coevolution and disease dynamics across the landscape with the benefits to parasites depending on their life history (e.g., simple vs. complex life cycles, generalists vs. specialists). Our synthesis highlights the complex ecological and evolutionary impacts of zoochory of freshwater organisms and raises questions for future research

Individual level microbial communities in the digestive system of the freshwater isopod Asellus aquaticus: Complex, robust and prospective

The freshwater isopod Asellus aquaticus is an important decomposer of leaf detritus, and its diverse gut microbiome has been depicted as key contributors in lignocellulose degradation as of terrestrial isopods. However, it is not clear whether the individual‐level microbiome profiles in the isopod digestive system across different habitats match the implied robust digestion function of the microbiome. Here, we described the bacterial diversity and abundance in the digestive system (hindgut and caeca) of multiple A. aquaticus individuals from two contrasting freshwater habitats. Individuals from a lake and a stream harboured distinct microbiomes, indicating a strong link between the host‐associated microbiome and microbes inhabiting the environments. While faeces likely reflected the variations in environmental microbial communities included in the diet, the microbial communities also substantially differed in the hindgut and caeca. Microbes closely related to lignocellulose degradation are found consistently more enriched in the hindgut in each individual. Caeca often associated with taxa implicated in endosymbiotic/parasitic roles (Mycoplasmatales and Rickettsiales), highlighting a complex host–parasite–microbiome interaction. The results highlight the lability of the A. aquaticus microbiome supporting the different functions of the two digestive organs, which may confer particular advantages in freshwater environments characterized by seasonally fluctuating and spatially disparate resource availability

A set of new and cross-amplifying microsatellite loci for conservation genetics of the endangered stone crayfish ( Austropotamobius torrentium )

Like other indigenous crayfish species in Europe, the stone crayfish (Austropotamobius torrentium) is endangered due to habitat degradation, competition with invasive American crayfish and a deadly disease (crayfish plague) vectored by these invaders. To study the genetic diversity and connectivity of the remnant stone crayfish populations, eight new microsatellite loci were developed and supplemented by four cross-amplifying loci developed for related species. These twelve loci were tested for polymorphism in 130 stone crayfish from five streams in Switzerland. Variability was low with 1-7 alleles per locus, but the markers revealed strong genetic differentiation among streams. Use of these microsatellites will provide important information for the conservation and management of this endangered species

Parasite DNA detection in water samples enhances crayfish plague monitoring in asymptomatic invasive populations

Invasive species can facilitate the spread of pathogens by first providing asymptomatic host reservoirs, and then driving disease outbreaks in native populations through pathogen spillover. An example of this are invasive crayfish species in Europe (Faxonius limosus, Pacifastacus leniusculus, Procambarus clarkii), which carry the deadly plague agent (Aphanomyces astaci). Effective disease management requires comprehensive monitoring, however, pathogen detection in carrier populations with low pathogen prevalence and intensities is challenging. We simultaneously collected and analysed crayfish tissue samples of invasive crayfish populations and water samples to compare A. astaci detection in different sample types using quantitative PCR. Combined, the two sampling methods revealed A. astaci presence with DNA concentrations above limit of detection (LOD; the lowest concentration which can be detected with reasonable certainty) in 13 of 23 invasive crayfish populations. In four additional sites, A. astaci DNA concentrations below LOD were found in water. In four populations only were A. astaci concentrations above LOD detected in both sample types and in three populations in concentrations above LOD in tissue but below LOD in water. The likely reason for these discrepancies is the low A. astaci prevalence and concentration in resistant invasive crayfish, which limit detection reliability. Consistency may be improved by timing surveys with seasonal periods of high A. astaci abundance and by increasing water sampling effort. Considering the ease of collecting eDNA samples, compared to crayfish tissue sampling, eDNA methods would facilitate frequent and comprehensive surveys. However, remaining uncertainties in eDNA-based detection reveal the relevance of combining monitoring tools to improve detection of invasive pathogens and their management

Multiple sclerosis in Finland 2018-Data from the national register

Objectives Finland is a high-risk multiple sclerosis (MS) region, but a national MS register has not existed until 2014. In this paper, we present the Finnish MS register variables and data collected by 31 December 2018. Materials and Methods Numbers and data counts of MS patients in the register (ICD-10 code G35) are presented. The disease types and proportion of patients receiving disease-modifying treatments (DMTs) were analysed in five hospital districts with most complete data sets. MS prevalence in Finland was estimated using administrative hospital discharge data as an additional resource. Results There were a total of 8722 MS patients in the Finnish MS register by 31 December 2018 (71.5% females). Mean age at MS diagnosis was 38.7 years and peak prevalence was at age 50-54 years. Disease course was relapsing remitting (RRMS) in 66.7%, secondary progressive (SPMS) in 13.5%, and primary progressive (PPMS) in 7.9% of the 5365 MS patients in the selected districts with most complete data. A total of 66.0% of RRMS patients, 19.6% of SPMS patients and 9.9% of PPMS patients were receiving DMTs. By combining MS register data with databases of those hospitals that had not joined the register, the nationwide prevalence estimate was between 10 and 11 thousand patients (corresponding to crude prevalence 180-200/100 000). Conclusions The Finnish MS register is currently used in 15/21 Finnish hospital districts. By register integration into the electronic patient files, the coverage of the register has increased to approximately 80% of the estimated Finnish MS population.Peer reviewe