Faculty of Agriculture and Forestry


Recent Submissions

  • Kalmu, Niina (Helsingin yliopisto, 2021)
    Poultry meat has become popular in human diet and to secure the growing demand of poultry meat, breeders have developed broilers with fast growth and high breast muscle yield. Because of this genetic selection modern broilers are suffering from various quality defects in their breast muscles, one of which is called WB myopathy. The aim of the thesis was to study whether exercise, WB status or age have effects on ultimate pH and glycolytic potential (sum of total glucose and lactic acid content, given as lactate) in M. pectoralis major of modern broilers chickens. A total of 154 post-rigor breast muscle samples of male broilers of hybrid Ross 308 were used in this study. Broilers were divided randomly into three groups (A-C). Group A birds were not subjected to any exercise during the experiment. Group B birds lived 25 days exactly like group A but after that the drinking water dispensers was elevated to a higher level. Group C birds had their drinking water dispensers elevated to a 5 cm higher level after three days, and it was risen stepwise to 25 cm during the study. Broilers were slaughtered randomly from different groups at 20, 30 or 41 days old. Group B results were disregarded due to technical problems. Initial and ultimate pH, total glucose, free and in glycogen, and lactic acid contents for glycolytic potential, were determined from the breast muscle samples. The results showed that there were no differences between groups A and C (p > 0.05). There were differences between normal and WB cases in ultimate pH (pHu; p = 0.000), total glucose content (p = 0.000), lactate content (p = 0.007) and glycolytic potential (p = 0.000), but the pH values 5 minutes after death showed no significance (pH5; p = 0.190). There were differences in pHu, total glucose and glycolytic potential (p = 0.000), and lactate (p = 0.007), between ages 20, 30 and 41 days old birds. As the severity of WB increased in the breast muscle, the pHu increased and total glucose, lactate content and glycolytic potential decreased. The correlations showed significant relationships between WB score and all the above variables (p < 0.000). The results of the current study show that exercise does not have an effect on the levels of carbohydrates in M. pectoralis major of modern broiler chickens, but WB status and increasing slaughter age result a decrease in glycolytic potential and increase in ultimate pH.
  • Sinkkonen, Emma (Helsingin yliopisto, 2021)
    Mutschli is a Swiss-type, mild but tasteful, cheese which has similar properties and manufacturing process as Raclette cheese. It is produced in Switzerland where traditional Alpine cheesemaking takes place. Mutschli means small semihard cheese and it is often produced as applied product, so the manufacture protocol varies among the cheesemakers. Although Mutschlis are very common products of the Alpine dairy plants, there is a limited amount of manufacturing specifications and studies available. The aim of this study is to clarify the manufacturing process of Swiss-type Mutschli cheese and the parameters that may have an effect on the final product. There are many techniques in cheesemaking controlled by the cheesemaker that determine the cheese sort and quality. Usually, the local artisanal Swiss cheeses are made of raw milk. Besides the destruction of pathogenic bacteria, pasteurization may induce other significant changes in milk that are relevant to cheesemaking. In this study the effect of pasteurization and lower heat treatment, thermization, on milk was studied. Significant differences between tested heat treatments (thermization and pasteurization) of raw milk were not found and microbiological quality of cheeses was satisfactory. On the other hand, thermization always creates a risk for the presence of Listeria monocytogenes. The effect of short pressing during molding was also investigated and differences between pressing techniques were also not significant. Pressing the Mutschli with 0,01 bar for one hour did not affect the dry matter content or simple appearance of the texture. According to previous studies pressing with higher pressure or for a longer time can cause some effects. However, in this study the results were adequate and relating to the techniques used in the manufacturing process, successful manufacture of Swiss-type Mutschli cheese was formed.
  • Takamäki, Saana (Helsingin yliopisto, 2021)
    Anthropogenic greenhouse gas concentrations have raised alarmingly high in the atmosphere during the last century and there is an urgent need for cost-effective climate policies to tackle climate crisis. European Union’s Emission Trading System (EU ETS) is the major market instrument for decreasing the emitted greenhouse gas emissions cost-effectively in the European Union. In addition, EU member states apply complementary and partly overlapping policies with EU ETS. Such demand-reducing policies do not affect the total amount of emissions at the EU level when the emission cap is binding because of the observed “waterbed effect”. However, the effectiveness of overlapping demand-reducing policies has changed due to the implemented Market Stability Reserve, which absorbs allowances from the market while endogenizing the emission cap. Furthermore, market agents can unilaterally cancel emission allowances from the market to tighten the emission cap. Previously Finnish Government committed to phase-out coal by 2029 in order to decarbonize the national energy system. However, there is no full certainty regarding to what extent does the Finnish coal ban reduce total emission at the EU level. Thus, the aim of this thesis is to quantify the cumulative impact of Finnish coal ban and its effectiveness to reduce emission at the EU level. This thesis determines how many allowances shall be unilaterally cancelled at different years to guarantee that the coal ban has a full effect on the total emissions at the EU level. A scenario analysis is conducted through model simulations to showcase how the effectiveness of coal ban could be maximized while minimizing the costs related to unilateral cancellation. This thesis contributes to the limited literature on unilateral cancellations as an instrument to strengthen the effectiveness of overlapping demand-reducing policies within the EU ETS. The results show that the unilateral cancellation is more cost-effective when implemented after the MSR has stopped absorbing allowances from the market because until then, the unilateral cancellation policies are rather low in cost-effectiveness. In addition, earlier the coal phase-out policies are implemented the higher is the effectiveness of the coal ban due to the higher synergies between Market Stability Reserve and demand-reducing policies.
  • Jyry, Annika (Helsingin yliopisto, 2021)
    Whey is a significant side stream in the cheese making industry, and it can be utilized in several ways especially because whey proteins are nutritionally valuable. Whey cheeses are produced all around the world and mostly in small scale and traditional ways. The production of Ziger whey cheese has a long tradition in Switzerland, and it requires fresh whey derived from rennet-induced cheese making. The whey proteins are precipitated by high manufacturing temperature, the addition of acid and NaCl. The goal of this master’s thesis is to develop a Ziger whey cheese that can be applied in the Finnish dairy industry including optimization of the manufacturing process emphasizing the manufacturing temperature. The thesis also investigates and compares the effect of the temperature on the moisture, protein, and fat content and the yield of the Ziger whey cheese. Also, this thesis aims to examine the effect of the manufacturing temperature on the shelf life by monitoring microbial and physicochemical parameters of the Ziger whey cheese over 21 days of storage. The manufacturing temperatures examined in the production of Ziger were 88 oC and 93 oC, and the production was repeated three times for both temperatures which resulted in altogether six production series. The temperature had a significant effect on the yield which concluded, that the higher the temperature was during the manufacture, the higher the yield was. The microbiological quality was not affected by the manufacturing temperature. However, during the storage there was a significant correlation between the growth of lactic acid bacteria and the pH value i.e., the bacterial count increased as the pH value decreased. After 21 days of storage, every Ziger whey cheese sample crossed the threshold of spoilage for the total viable count which was set at 107 CFU/mL. The manufacturing temperature had no impact on the protein and fat contents. Instead of the manufacturing temperature, there was a strong correlation between the moisture and the fat content. Based on the fat content, the Ziger whey cheese can be categorized as creamy and soft whey cheese. For future reference of research, the quality and shelf life of Ziger whey cheese could be improved by modified atmosphere or vacuum packaging, high packaging temperatures, and shorter drainage time. Moreover, the production could be made more efficient by a continuous process in comparison to batch production.
  • Ansung, Kim (Helsingin yliopisto, 2021)
    Understanding the relationship between plant-based diets and mental health has become an important issue from a public health perspective, not only for researchers but also in everyday life. In particular, this study focused on university students since more and more students have been limiting their animal-based foods intake. At the same time, there has been a global trend of increasing mental disorders and distress among university students. Poor mental health conditions, such as depression and anxiety, could associate with students' academic achievement. This study examined the connections between diet choice, mental health, and academic achievement. This study used cross-sectional data from the Student Health Survey 2016 by the Finnish Student Health Service (FSHS). Among 3029 participants (aged 18 to 35 years) from either academic universities or universities of applied sciences in Finland, the questions from the Index of Diet Quality (IDQ) were used to construct four different diet types: 67 vegans (2.2%), 281 vegetarians (9.3%), 291 semi-vegetarians (9.6%), and 2390 omnivores (78.9%). Mental health status was measured by using two indicators: self-reported diagnosed mental disorders (depression and/or anxiety) and the General Health Questionnaire-12 (GHQ-12), which screened minor psychiatric disorders. Academic achievement was measured by asking about perceived academic success. The logistic regression models were used in the main analyses. The two different mental health status were analysed with adjustment for potential confounding variables such as sociodemographic factors, health-related behaviour, BMI, and disease conditions. The academic achievement was analysed with adjustment for potential confounding variables such as sociodemographic factors, health-related behaviour, BMI, disease conditions, enrolment period, and right field of study. Also, this study further examined the association between food groups and academic achievement. The results showed that compared to the omnivorous diet, the vegetarian diet was associated with higher odds of diagnosed mental disorders (OR [95% CI]: 2.74 [1.80–4.16], p<0.001) and minor psychiatric disorders screened by GHQ-12 (OR [95% CI]: 1.68[1.22–2.30], p<0.001) after adjustment for all potential confounders. Although a positive relationship between fish consumption and academic achievement was found (OR [95% CI]: .88[.80–.96], p<0.01), there was no statistically significant association between diet types and academic achievement. In addition, higher sweets consumption was related to higher odds of being less successful than students had expected (OR [95% CI]: 1.08 [1.01–1.15], p<0.05). The results indicate that vegetarian university students are more likely to have lower mental health status than non-vegetarian students on average. In addition, academic achievement is associated with the consumption of specific food items rather than diet types. Overall, the findings suggest that vegetarian students should carefully monitor their mental health status. Also, students should be supported to improve their food choice and dietary quality for their academic achievement. The study results can be implicated in public health interventions to improve students' well-being among higher education students. In future research, it may be beneficial to apply more various classifications and measures of diet types and academic achievement and examine the temporal relationship between diagnosed mental disorders and the diet chosen.
  • Rapo, Aleksi (Helsingin yliopisto, 2021)
    The geographical origin of food can be determined by analyzing stable isotope ratios of hydrogen and oxygen from water samples that have been extracted from food matrices. A geographical gradient is formed from isotope ratios of water constituents, due to the small mass differences of the different isotopes, which can be also seen in the growing plants in certain regions. Finnish Food Authority has established a method for differentiating domestic and foreign strawberry samples, which uses a database that was created for Finnish strawberries. To produce a representative water sample from food, almost all of the water needs to be extracted from the matrix. The aim of this master’s thesis was to establish and optimize the extraction process of water from strawberry samples with a cryogenic vacuum extraction (CVE). The secondary objective was to test if isotopic values of Finnish strawberries differ from that of foreign strawberry samples and thus be used for determining the domesticity of strawberries. The performance of the cryogenic vacuum extraction procedure was confirmed with three validation tests which tested extraction effect on the sample’s isotope ratios of hydrogen and oxygen, cross-contamination between extraction units and suitable sample fixing materials. The optimization did not reach acceptable accuracy as there were no significant differences between the experimental runs for the Box-Behnken design (BBD). The reason showing ineffective modelling of the design remains unknown, especially as the response surface diagram shows clearly the optimal and minimal trends of the tested factors for δ2H. However, this was not so evident for δ18O. The ranges of tested factors may partly explain this discrepancy. Nonetheless, the differentiation of foreign and domestic strawberry samples was successful with principal component analyses. However, several factors concerning cryogenic vacuum extraction and water extraction in general, such as recovery of water, sample pretreatment, sample storage, different sample matrices and coextracted compounds as well as extraction parameters, need to be addressed in future studies.
  • Ahlberg, Juho (Helsingin yliopisto, 2021)
    Ruokasipuli (Allium cepa Cepa-ryhmä L.) on maailmanlaajuisesti merkittävä viljelykasvi ja Suomessa se kuuluu tärkeimpiin puutarhakasveihin. Suomessa sipulia viljellään pääasi-assa tuonti-istukkaista, joissa on havaittu useita sipulia vioittavia Fusarium -lajeja. Sipulilla taudit aiheuttavat merkittäviä tappioita, joten jotkut viljelijät ovat siirtyneet viljelemään si-pulia itsetuotetuista taimista tautiriskin vähentämiseksi. Sipulin kylväminen suoraan avo-maalle voisi kuitenkin olla edullisempi vaihtoehto, mutta osaa Ahvenanmaata lukuun otta-matta kasvukausi ei ole tähän riittävä Suomessa. Samco-tekniikka on alun perin maissille kehitetty viljelytekniikka, jossa siemenet kylvetään valossa hajoavan muovin alle. Mene-telmä voi valmistajan mukaan mahdollistaa pitkää kasvukautta vaativien kasvien viljelyn entistä pohjoisemmassa. Tämän tutkielman tavoitteena oli selvittää kylvösipulin viljelyn mahdollisuuksia Suomessa Samco-tekniikan avulla, sekä selvittää kylvötiheyden vaikutusta sipulin satoon ja sen kokojakaumaan. Koejärjestely oli satunnaistettujen lohkojen osaruutukoe, jossa pääruudut muodostuvat neljästä kylvötiheydestä ja osaruudut viljelymenetelmästä, joita on kaksi; Samco-tekniikka ja perinteinen kylvösipuli. Koeruuduilta korjatuista sipuleista määritettiin kauppakelpoinen sato, kokojakauma sekä viallisten sipuleiden osuus kokonaissadosta. Vil-jelymenetelmän ja kylvötiheyden vaikutukset sadon määrään, sen kokojakaumaan ja vial-listen sipuleiden määrään selvitettiin kaksisuuntaisella varianssianalyysillä. Samco-tekniikka alensi kokonaissatoa 26 % verrattuna perinteiseen kylvösipuliin, lisäksi Samco-tekniikka tuotti pienempikokoisia sipuleita. Kylvötiheys ei vaikuttanut sadon koko-naismäärään, mutta suurin kylvötiheys lisäsi pienikokoisen sipulin osuutta sadosta sekä Samco-ruuduilla, että kontrolleissa. Rikkakasvitorjunta Samco-tekniikan yhteydessä osoit-tautui vaikeaksi, ja menetelmän negatiiviset vaikutukset satoon johtuvat todennäköisesti li-sääntyneestä kilpailusta rikkakasvien kanssa. Koelohkolla esiintyi huomattavasti juolaveh-nää (Elymus repens L.) ja peltovillakkoa (Senecio vulgaris L.). Tämän tutkimuksen perus-teella Samco-tekniikka tuomaa hyötyä kylvösipulin viljelyyn ei voida arvioida koejärjeste-lyn puutteiden takia. Lisätutkimus rikkakasvitorjunnan vaikutuksesta Samco-tekniikalla viljeltyyn kylvösipuliin olisi kuitenkin tarpeen.
  • Tikkanen, Elina (Helsingin yliopisto, 2021)
    Internationalization provides firms a significant opportunity for growth and value creation worldwide. Especially those companies that operate in small and open economies tend to benefit from foreign market expansion. For example, the small size of Finland’s economy sets limitations to the domestic market opportunities. In addition to Finland’s macro-level strengths, Finnish companies’ innovativeness has gained attention as a potential sustained competitive advantage to support firm internationalization. Despite the identified potential, the Finnish food sector’s internationalization has been modest, and the research in this field has been limited. Thus, this thesis studies the internationalization phenomenon in the context of innovative Finnish food sector companies. The purpose of the research is to explore firm internationalization from the process perspective by investigating companies’ time-based decision making and behavior. The thesis aims to find out how and why do innovative Finnish food companies internationalize? The research was carried out as a qualitative study because the purpose was to form an in-depth understanding of the internationalization processes of Finnish food companies. In addition to the empirical research, an extensive literature review of various internationalization theories was conducted to develop a theoretical framework of the studied phenomenon. A multiple-case study was selected as the research strategy and two case-companies were selected, one representing a young SME and the other well established MNE. Both case companies were of Finnish origin, they operated in the food sector and had experience of expanding into international markets. The research data was collected through semi-structured interviews with company representatives, as well as by reviewing companies’ websites, publications, annual reports, and newspaper articles. The key findings of this study show that, in line with the initial hypothesis, food companies can utilize different internationalization strategies depending on their internal capabilities and resources. The accumulation of decisions regarding main internationalization dimensions and the actions taken based on these decisions in relation to time showed two different internationalization processes. The MNE had internationalized incrementally in line with traditional internationalization theories. On the contrary, the SME had internationalized early and rapidly on a global level. In addition, the company’s product portfolio was found to have a significant impact on decision-making and company-level behavior. Lastly, the innovativeness and uniqueness of both the products and the company’s know-how were shown to have a positive impact on achieving a sustainable competitive advantage on a global level.
  • Saha, Sani (Helsingin yliopisto, 2021)
    Immunodeficiency in neonatal piglet is one of the major causes of pre-weaning mortality. Colostrum supply cytokines to newborn piglets, which play an important role in formation of their immune mechanism. This study aims to identify the relationship between sow’s blood and colostrum cytokines, and effect of resin acid-enriched composition (RAC) in sow’s blood and colostrum cytokines concentration. RAC is a plant extract of coniferous tree, and it is composed of resin acids and fatty acids which exert immunomodulatory function. Two experiments were conducted in two different farms where RAC was supplemented in the diet of late gestation sows, starting from one week before of expected farrowing date till farrowing. Multiplex immunoassay was used to determine the interferon alpha (IFN-α), interferon gamma (IFN-ɣ), interleukin 1 (IL-1), interleukin 10 (IL-10), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 8 (IL-8), tumor necrosis factor alpha (TNF-α) and interleukin 12p40 (IL-12p40) cytokines concentration in blood and colostrum of sow collected within 2 hours of the birth of first piglets. There were significant (p < 0.05) positive correlations between sow’s blood and colostrum cytokines concentration. RAC-fed sows had significantly (p < 0.05) higher level of IL-1 and showed positive tendency (p = 0.1) to increase TNF-α cytokine level in blood. Colostrum level of IFN- ɣ, IL-1 and IL-12p40 had also positive tendency (p = 0.1) to rise in RAC supplemented sow. On this basis, it is proposed that application of RAC in late gestation sow diet enhance the cytokine production in sow’s blood, and blood cytokines levels are positively correlated with colostrum cytokines.
  • Kamppuri, Elli-Noora (Helsingin yliopisto, 2021)
    Suot ovat maapallolla sekä merkittäviä hiilivarastoja että suurimpia luontaisia metaanin lähteitä. Metaani on toiseksi merkittävin kasvihuonekaasu hiilidioksidin jälkeen ja voimakkuudeltaan moninkertainen hiilidioksidiin nähden. Koska suot tuottavat paljon metaania, on tärkeä selvittää, mitkä tekijät vaikuttavat soiden metaanintuotantoon ja sen suuruuteen. Subarktisen ilmastovyöhyk-keen minerotrofisten sarasoiden on todettu tuottavan suhteessa enemmän metaanipäästöjä verrattuna muiden ilmastovyöhykkei-den vastaaviin soihin, vaikka yleensä korkeampien leveyspiirien suot tuottavat vähemmän metaania matalampien leveyspiirien soihin nähden. Porojen laidunnuksen on pohdittu vaikuttavan subarktisten minerotrofisten sarasoiden suuriin metaanipäästöihin. Minerotrofiset sarasuot ovat tärkeitä laidunnusalueita poroille pohjoisessa Fennoskandiassa erityisesti kesäaikaan. Laiduntavat herbovorit muokkaavat ekosysteemiään monilla tavoilla sekä suoraan että epäsuorasti. Laidunnuksen on todettu eri arktisilla ja subarktisilla ekosysteemeillä suosivan muun muassa sarakasvien kasvua ja lisäävän maaperän mikrobistoa ja sen aktiivisuutta ulosteiden ravinnelisäyksen ansiosta. Lisäksi porot märehtijöinä voivat muokata metaanintuotantoa suoekosysteemissä, jos pöt-sin metanogeenisiä mikrobeja kulkeutuu papanoiden mukana suohon. Tässä pro gradu -tutkielmassa selvitetään, miten poron papanoiden lisääminen suolle vaikuttaa suon metaanipäästöihin ja kasvilli-suuteen. Työssä halutaan selvittää, millaisia vaikutuksia papanalisäyksellä on suon kasvien kasvuun, kasvilajisuhteisiin ja niiden kautta metaanipäästöihin. Uskotaan, että poron papanat lisäävät suolla sarakasvien runsautta, jotka kuljettavat solukoissaan metaania ja näin lisäävät suon metaanipäästöjä. Papanoiden aiheuttaman ravinnelisäyksen epäillään muuttavan kasvilajisuhteita siten, että enemmän ravinteita vaativat lajit lisääntyvät. Papanalisäyksen uskotaan lisäävän suon metaanipäästöjä myös aktivoi-malla suon metanogeenisten mikrobien toimintaa. Papanalisäyksen vaikutus kasvillisuuteen ja metaanipäästöihin oli hyvin vähäi-nen ensimmäisen kasvukauden aikana (Salovaara 2020). Tässä pro gradu -työssä seurataan papanalisäyksen vaikutusta pidem-mällä aikavälillä, sillä muutokset kasvillisuudessa voivat olla hitaita ja vaikutukset metaanipäästöihin kehittyä vasta myöhemmässä vaiheessa. Lisäksi tutkimuksessa selvitetään, miten pelkkä turve ilman kasvillisuuden vaikutusta reagoi papanalisäykseen maasto-olosuhteissa. Aineiston keruu tähän tutkielmaan tapahtui 1.6.-31.8.2020 Pohjois-Suomessa. Tutkimuskohteina oli kaksi minerotrofista sarasuota Lapissa. Ensimmäinen suo oli Lomponlonjänkkä Pallasjärvellä Muoniossa ja toinen Halssiaapa Sodankylässä. Lompolonjänkällä oli 27 mittauspistettä ja Halssiaavalla 18. Mittauspisteiltä mitattiin 1-2 viikon välein metaanipäästöt, lehtiala, pohjavedenpinta ja turpeen lämpötila. Lompolonjänkän mittauspisteistä kuusi oli sellaista, joista kaikki pintakasvillisuus poistettiin, jotta papanali-säyksen vaikutusta turpeessa voisi seurata. Lisäksi suolla tehtiin inkubointikoe, jonka tarkoituksena oli selvittää, miten poron papanat hajoavat turpeessa. Tulosten perusteella poron papanat lisäsivät metaanivuota Halssiaavan jänteillä ja välipinnoilla, kun ne lisäämisen jälkeen survottiin suohon. Lompolonjänkällä metaanivuo oli pienempi mittauspisteillä, joille oli lisätty papanoita. Uusilla kasvittomilla ja kasvillisilla mittauspisteillä ei havaittu muutoksia metaanivuossa. Kasvillisuuden lehtialassa ei huomattu vaihtelua laidunnuksen tai papanali-säyksen takia Lompolonjänkällä. Halssiaavan jänteillä laidunnus ja papanalisäykset näyttivät pienentävän lehtialaa. Myös välipin-noilla laidunnus pienensi lehtialaa. Uppolisäyspisteillä lehtiala pieneni, mutta biomassa antoi tästä päinvastaisen tuloksen. Papa-noiden hajoaminen turpeessa oli nopeampaa lähempänä pintaa. Kolmen kuukauden aikana pintapapanoiden kuivamassa pieneni puoleen ja pohjapapanoiden kahteen kolmannekseen. Papanoiden vaikutus metaanivuohon näyttäisi ilmenevän vasta seuraavana kasvukautena. Lompolonjänkällä papanoiden ravinneli-säys paransi ruohojen kasvuolosuhteita, mikä runsastutti niiden määrää suhteessa saroihin. Tämä vaikutti metaanivuohon laske-vasti. Halssiaavan välipinnalla ruohoja ei esiintynyt mittauspisteillä lainkaan, minkä takia papanalisäys näytti vaikuttavan positiivi-sesti saramaisten kasvien kasvuun uppolisäysaloilla ja näin ollen kohotti metaanivuota. Jänteillä pintalisäyspisteiden lehtiala oli kontrollia pienempi, mutta metaanivuo selkeästi suurempi. Jännepinnoilla lehtiala ei näyttäisi korreloivan samalla tavalla metaa-nivuon kanssa kuin välipinnoilla.
  • Junttila, Maijuleena (Helsingin yliopisto, 2021)
    Finnhorse is a native Finnish horse breed and its studbook has four different sections: riding horse, trotting horse, pony-sized horse and working horse. Most of the Finnhorses are registered as trotters. The Finnish trotting and breeding association Suomen Hippos ry is responsible of the breeding value estimation. The official breeding value estimation includes earnings, racing time, time difference at finish, disqualifications and career starting age. The objective of this study was to update variance components for earnings and racing time and to estimate variance components for the racing career length and first year earnings as new traits. Data was received from The Finnish trotting and breeding association Suomen Hippos ry and it contained racing results from years 1984 to 2018. For this study, the data was limited to competition years 2000-2018 for earnings and racing time. For the career length and the first year earnings the data were limited to birth years 1990-2004. The data included trotting race starts from stallions, geldings, and mares. Geldings and stallions competed approximately 60% of the starts. Age was grouped annually from 3 years old to 8 years and older horses. Finnhorse can start racing on September 1st of the year when it turns three years of age and it can race till end of the year when it turns 15 years old. In addition to gender and age, the year of race was included as a fixed factor in the estimation of variance components. The data was processed with RStudio-program. The pedigree file was processed with RelaX2-program and DMU-program’s REML was used for the variance component estimation. The repeatability model was used for the earnings and racing time, since there were multiple observations per animal per year. For the career length and the first year earnings, there were one observation per animal. Heritability estimate for earnings (0,26±0,01) and racing time (0,40±0,02) were moderate. Heritability estimates are similar to those used in the official breeding value 0,30 and 0,35, respectively. The heritability of the career length was low 0,09±0,01 and the first year earnings was moderate 0,26±0,04 which was the same as the earnings trait that included all competition years. The genetic trends were positive for all the studied traits. The genetic correlation between the earnings and the racing time was high -0,94±0,01. This was expected since these two traits illustrates quite the similar features. The genetic correlation between the career length and the earnings of the first year was also high 0,65±0,08. This predicts that moneywise well performing trotter is likely to do a longer career compared to a horse that does not earn that much. The results show that if earnings is used in selection also the length of the career improves genetically.
  • Norrback, Josefin (Helsingin yliopisto, 2021)
    Gastrointestinal parasites (GIP) and resistance against anthelmintics are and will be one of the biggest challenges for the sheep husbandry. Research within this area is very important today and it is important to figure out new methods to identify individuals with high burden of parasites and to treat just these individuals. The aim of the study was to investigate the effects of GIP on activity patterns and weight gain in first season grazing lambs. A sub-study accompanied with the aim was to see if the manually made behavioural observations supported data from the sensors. The study took place at the Swedish University of Agricultural Sciences (SLU) during the summer of 2019. The study was divided into two experimental periods. In the first experimental period 30 ewes and their 60 twins were used. Of those, 58 lambs continued to the second experimental period. Two groups were dewormed with ivermectin (high group) and two groups were untreated (low group). All lambs were fitted with sensors, and the data was downloaded once a week, at the same time with the weighting of animals. Individual faecal samples were collected four times. The pasture where the lambs grazed was a first-year pasture. Sward height was measured, and herbage samples were collected three times during the experiment. Herbage samples were analysed for nutritional and mineral content. The manual behavioural observations were made two days a week during five weeks. The high group had higher weight (28.9 kg) in the beginning of the experiment, compared with the low group (28.1 kg). On the contrary, the high group had lower weight (42.7 kg), compared with the low group (44.8 kg) at the end of the experiment. According to data from the sensors there were differences in lying time and motion index (MI) during the 7-10 first days after weaning. The low group laid down more, compared with the high group. The low group had higher MI compared with the high group. During the whole experiment there were no differences in lying time, lying bouts or MI. The manual behavioural observations showed that “standing still” had significantly more registrations for the high group compared to the low group. It is possible to see differences in behaviour with sensors at an early stage of parasitic infection, even with low levels of parasites. This means, that there is a potential to use automatic behaviour observations as a diagnostics tool during infection of GIP.
  • Lampinen, Anniina (Helsingin yliopisto, 2021)
    The natural carbon cycle is affected by human activity. Terrestrial carbon stocks have been decreasing as at the same time carbon dioxide concentration in the atmosphere has increased causing climate change. The Paris Agreement sets the target to limit climate change to 1.5°C and to reach that goal, all possible mitigation practises should be included into global framework to avoid the most serious consequences of warming. Carbon sequestration into natural soil and biomass could be one mitigation practice. To enhance carbon sequestration activities and to include natural carbon stocks into to the EU climate policy, it would be necessary to quantify stock sizes and changes in those stocks. For developing carbon trading markets, the quantification methods should provide accurate results and at the same time be practical and financially achievable. Used research method in this thesis was comparatively literature survey and aim was to gather and compere information about currently used carbon stock quantification methods against developing carbon trading markets. Soil carbon stocks can be quantified with direct soil sampling, spectroscopic sensing methods or by mathematical models. Biomass carbon stocks can be quantified with inventory-based field measurements and modelling and by remote sensing. The full carbon budget on the ecosystem level can be achieved with carbon flux measurements. Quantification of different terrestrial carbon stocks and their changes is not a simple task. There is a lot of variation between different stocks and in some cases, the stock changes occur slow. Cost of carbon stock quantification depends on the accuracy, size of the area under focus and frequency of the measures. Methods for terrestrial carbon stock quantification are dependent on high quality data and there is demand for research considering carbon sequestration. For carbon offsetting purposes of developing carbon markets, the modelling approach is achievable, cost efficient, repeatable and transparent. There is no perfect model or one universal model that would fit to every situation and thus the differences must be known. At this stage, this approach could be one possibility to include small scale projects and enhance climate actions. Different quantification methods provide information which can be used to different method developments and to increase accuracies. It’s important to know, how all information can be effectively utilized.
  • Ensiö, Meri (Helsingin yliopisto, 2021)
    Kaupungistuminen on uhka luonnon monimuotoisuudelle. Sen merkittävimpiä haittavaikutuksia ovat elinympäristöjen katoaminen ja jäljelle jääneiden alueiden kytkeytyneisyyden heikentyminen. Lisäksi monille lajeille tärkeät kosteikot ovat vaarassa hävitä kaupunkirakentamisen tieltä tai kärsiä muista ihmistoiminnan aiheuttamista haitoista. Sammakkoeläimet ovat elinkiertonsa aikana riippuvaisia sekä maa- että vesiekosysteemeistä, joten kosteikot ovat niille välttämättömiä. Ne ovat paikallisia eläimiä, jotka eivät pysty siirtymään nopeasti uusille alueille. Siksi ne ovat erityisen herkkiä kytkeytyneisyyden heikentymiselle ja muille kaupunkiympäristön haasteille, kuten lisääntymis- ja talvehtimisympäristöinä toimivien kosteikkojen häviämiselle. Sammakkoeläinten monimuotoisuus ja määrä vähenevätkin yleensä lähestyttäessä tiheään rakennettuja keskustoja. Tämän tutkimuksen tavoitteena on selvittää huonosti tunnettujen sammakkoeläinten lajikirjoa ja runsautta pääkaupunkiseudun eli Helsingin, Espoon ja Vantaan kosteikoilla sekä tarkastella onko elinympäristöjen kytkeytyneisyydellä vaikutusta sammakkoeläinten runsauteen ja lajimäärään tutkimusalueella. Lisäksi selvitetään vaikuttaako kosteikon kasvillisuus ja sitä ympäröivän alueen maankäyttö sammakkoeläimiin. Tutkimuksessa on mukana neljä pääkaupunkiseudulla tavattavaa sammakkoeläinlajia: ruskosammakko (Rana temporaria), viitasammakko (Rana arvalis), rupikonna (Bufo bufo) ja manteri (Lissotriton vulgaris), jotka kartoitettiin 50 kosteikolta. Manterin läsnäolo kartoitettiin aktiivisuuspyydyksillä, ja muiden lajien läsnäolo selvitettiin kurnutuslaskentojen avulla keväällä 2018. Kasvillisuuden peittävyys arvioitiin maastossa koeruutujen avulla, ja maankäyttöä tutkittiin paikkatietoanalyysiä hyödyntäen. Kosteikkojen kytkeytyneisyyden määrittelyyn käytetään pääkomponenttianalyysiä, jonka perusteella ne luokiteltiin kolmeen luokkaan: heikosti kytkeytynyt, hyvin kytkeytynyt ja erinomaisesti kytkeytynyt. Sammakkoeläimiä havaittiin 40 kosteikolta. Yleisin havaittu laji oli ruskosammakko ja toiseksi yleisin manteri. Viitasammakosta ja rupikonnasta kertyi vain vähän havaintoja. Sammakkoeläinten lajimäärä, sekä ruskosammakon ja viitasammakon runsaus, olivat suurempia niillä kosteikoilla, jotka olivat hyvin kytkeytyneet. Lisäksi kolme tai neljä sammakkoeläinlajia havaittiin todennäköisemmin erinomaisesti kytkeytyneiltä kosteikoilta. Odotusten vastaisesti rupikonnan ja manterin runsaus olivat suurimmillaan heikosti kytkeytyneillä kosteikoilla. Sekä kosteikon kasvillisuudella että maankäytöllä havaittiin olevan merkitystä sammakkoeläimille. Runsas vesikasvillisuus vaikutti positiivisesti sammakkoeläinten lajimäärään sekä ruskosammakon ja manterin runsauteen. Puustoisten alueiden runsaus kosteikon lähistöllä vaikutti positiivisesti sammakkoeläinten lajimäärään ja ruskosammakon runsauteen. Lisäksi kosteikkojen määrä lähialueilla vaikutti positiivisesti sammakkoeläinten lajimäärään. Manterin runsauteen vaikutti negatiivisesti rakennetun alueen määrä kosteikon lähistöllä. Maankäytön merkitys ja sen vaikutukset sammakkoeläimiin on tärkeää tunnistaa, jotta elinympäristöjä voidaan suojella tehokkaasti. Tämä tutkimus vahvistaa käsitystä siitä, että pelkästään pienvesiä suojelemalla ei voida turvata sammakkoeläinten selviytymistä, vaan pitää huomioida myös kosteikkojen läheinen maaympäristö. Kaupunkiympäristössä on sammakkoeläinten kannalta tärkeää säilyttää mahdollisimman yhtenäisiä metsä- ja viheralueita sekä niiden välisiä yhteyksiä. Lisäksi on tärkeää ylläpitää runsasta vesikasvillisuutta kosteikoilla ja jättää kosteikkojen ympärille mahdollisimman luonnontilaisia suojavyöhykkeitä.
  • Tiira, Matilda Anniina (Helsingin yliopisto, 2021)
    High moisture extrusion (HME) can be used to create meat-like structures in plant-protein-based products. This study aimed to describe sensory and textural properties of minced-meat-like products made from a legume ingredient and a plant fibre concentrate using HME. Extrudates with two different ratios of the ingredients, both with and without added hydrocolloid, were produced for the study. Sensory profiling (n = 9) was conducted as generic descriptive analysis (GDA). Instrumental texture profile analysis (TPA) as well as a consumer study (n = 55) were done to complement the data. GDA attributes, TPA parameters and consumers’ hedonic responses were compared, and connections were studied. Also, TPA results were compared to those from sensory analysis, aiming to find connections between instrumentally and sensorially measured parameters. The dry ingredient ratio clearly affected hedonic responses, while the effect of added hydrocolloid was smaller. Several descriptive sensory attributes, such as bitterness, gumminess, cohesiveness and stickiness, were related to the hedonic responses to smell, texture and taste. Plant fibre concentrate content was also clearly linked to these descriptive attributes. Samples perceived as gummy, cohesive, less bitter and less sticky got higher hedonic responses, but TPA parameters could predict neither GDA attributes nor hedonic responses. The results of this study showed that certain ingredients have a clear impact on sensory attributes and therefore hedonic responses of the final products. To further improve the consumer acceptance, pre-processing of the ingredients could be studied. To explain the differences in textural properties, more research on the molecular level assembly of specifically fibres and carbohydrates in the matrix is needed.
  • Linnainmaa, Eeva (Helsingin yliopisto, 2021)
    Dairy cattle breeding has been driven by economics since the 1930s. For a longer period, the costeffectiveness of dairy farming has been poor, and the farmers have been forced to look for all possible ways to improve economics, through either reducing costs or increasing profit. Finland had in 2018 6250 dairy farms, which all differ from each other by size, economics and production environment. Finland participates to Nordic Cattle Genetic Evaluation (NAV) and uses Nordic Total Merit (NTM) as a joint total merit index for Finland, Denmark and Sweden. It has not been published, whether Finnish dairy farms would need more farm specific total merit indices. Breeding goal preferences do differ not only between farms but also between production types, since organic farmers tend to put more emphasis on production, compared to conventional. The aim of this study was to study whether economic values on breeding goal traits differ between farms and production types. Herd specific economic values were counted for ten breeding goal traits. The study was fulfilled with seven dairy herds, who differed from each other by herd size and production environment. Two of the herds were organic. The calculation of economic values was based on a bioeconomic model SimHerd. It is a stochastic simulation model, which simulates the herd in weekly steps, taking all events in a cow’s life into account. Traits analyzed in this study were chosen according to hypotheses of their economic values. Traits analyzed were ECM yield, mastitis, conception rate of cows, conception rate of heifers, cow mortality, calf mortality, claw and leg diseases, feed efficiency, body weight and other culling. Prices and variable costs as well as the phenotypic data of the farms was collected from the year 2018. Finnish milk production is highly dependent of subsidies, but due to their complexity, only direct subsidies for milk were considered in this study. Relations between traits were cut off from the model before simulation. The maximum number of cows for each farm was set to 1000 to improve the reliability of the simulations. Each trait was simulated three times: with the phenotypic data and then twice with changing the parameter. According to the results, the relative economic value of ECM yield was the highest for all farms. The highest economic values differ between farms, but on average the next highest economic values were for body weight, conception rate of cows and cow mortality. These economic values were in the same range for both conventional and organic farms. When relative economic values are presented as percentages of the sum of standardized economic values, traits affecting longevity cover together the greatest percentage. With improved longevity the cows have more productive years, which means greater lifetime milk yield, less replacement cots and smaller environmental impact. When results were compared between farms, they showed no need for farm specific TMI. A different TMI for organic production would need a further research.
  • Knappe, Aaro (Helsingin yliopisto, 2021)
    Tutkin maisterintutkielmassani suomalaisten kelloharrastajien näkemyksiä luksuksesta ja kuluttajien aktiivista roolia luksuksen merkityksien tuottajina. Kelloharrastajat osoittautuivat mielenkiintoiseksi aiheeksi. Aktiiviset harrastajat ovat joutuneet pohtimaan luksuksen merkityksiä osallistuessaan yhteisön toimintaan. Luksuksen vaikean määrittelyn ja tulkinnanvaraisuuden vuoksi tavoitteena oli tutkia, millaisena kelloharrastajat itse näkevät luksuksen. Aiheen tekee tärkeäksi luksuksen suuri yhteiskunnallinen merkitys ja jatkuva esillä olo mediassa sekä katukuvassa. Taustateoriana tutkimukselle toimii Veblenin huomiota herättävän kulutuksen teoria ja sen kritiikkinä toimiva keskustelu huomiota herättämättömästä kulutuksesta. Luksusta ja huomiota herättävää kulutusta on pitkään pidetty lähes synonyymeinä, ja vasta viime aikoina niiden yhtäläisyyttä on kyseenalaistettu. Tutkimus toteutettiin teemahaastatteluin syksyn 2020 aikana. Haastattelujen kohteena olivat Facebookin kelloharrastajat ryhmän jäsenet. Aineistoa lähestytään sisällönanalyysin avulla, jakaen materiaali kolmeen teemaan. Luksuksen määritelmiä lähestytään toiminnallisen, kokemuksellisen ja symbolisen maailman kautta. Näiden avulla on tarkoitus selvittää, millaisia merkityksiä kuluttajat itse antavat luksustuotteille. Tutkimuksen aikana selvisi, että kelloharrastajat tekevät selkeän jaon arvokkuuden ja luksuksen välille. Luksus nähtiin pääosin negatiivisessa valossa ja yhdistettiin juuri huomionhakuisuuteen sekä näyttämisen haluun. Erottamalla arvokkuus ja luksus toisistaan kuluttajat saavat neuvoteltua merkitykset sopimaan paremmin omaan maailmaan. Symbolinen maailma osoittautui haastavaksi tutkimuksen kohteeksi. Selkeä jako arvokkuuden ja luksuksen välillä aiheutti sen, että puhe luksuksesta erotettiin kokonaan omasta toiminnasta. Näin puhe luksuksesta esittäytyy pelkästään mielikuvina ja yleistyksinä luksuksen merkityksistä. Unelmien ja unelmoinnin tärkeys nousi kuitenkin vahvasti esille osana arvokkaiden tuotteiden kulutusta. Unelmoinnin kautta saavutetaan juuri suuri osa kulutuksen nautinnosta. Selkeä havainto oli myös kuluttajien halu tuottaa aktiivisesti merkityksiä. Luksuksella ja arvokelloilla ei itsellään ole sisäänrakennettuja merkityksiä, vaan ne syntyvät kuluttajien tekemän aktiivisen neuvottelun tuloksena.
  • Jussila, Henriikka (Helsingin yliopisto, 2021)
    Background: Migration has found to be associated with changes in eating habits. Typically, dietary acculturation occurs which means that the person adopts host country’s ways of eating. Previous studies suggests that dietary acculturation can have negative effects on person’s diet if the person adopts the host country’s way of eating processed foods that replace the traditional healthy foods of their own culture. The phenomenon is also reflected in other generations, with children and young people with a foreign background being found to eat more sweets and soft drinks than other peers. To promote the eating habits of families with children with a foreign background, a deeper understanding is needed of the factors behind eating habits. Ethnography offers an opportunity to increase understanding of everyday eating and produces descriptive data to complement traditional nutrition research. Objectives: The aim of this MS's thesis was to draw a picture of everyday eating in families with children and with a foreign background in Finland. The study participants were mothers with first- and second-generation foreign backgrounds and with different ethnic backgrounds. Methods: This was a qualitative study using an ethnographic design. The field of research was an open community space in the Helsinki metropolitan area. The data consisted of ethnographic interviews with mothers (n=23) and field workers (n=2), as well as participatory observations and pictures. The data was analyzed by coding and theming. The results were compared with the model of dietary acculturation created by Satia-Abouta and with previous literature. Results: The role of mothers in the food supply of families was central. They made a distinction between “everyday food”, “cultural food” and “Finnish food”. Everyday food was something easy and fast, while cultural food required time and expertise. Some of them prepared cultural food as everyday food, as it was a means of maintaining cultural heritage. Except for fruits, vegetables and vegetarian dishes played a smaller role in mothers’ stories than animal-based products (meat, chicken, fish) and carbohydrate-containing products (rice, pasta, potatoes). Ethnic shops in the area were perceived as comprehensive, although many bought only (halal) meat there. The mothers' eating habits showed dietary acculturation, as they had begun to prepare “Finnish foods” such as mashed potato or lasagna that were new to them. It was important for the mothers that their children ate well, and children’s lack of eating emerged as a concern. The mothers balanced between what foods children liked and what they considered as good for the child. They had searched and received ideas and information regarding eating on the Internet and from a Finnish counseling center. Conclusions: This study brought understanding of everyday eating in families with children with a foreign background in Finland. The ethnographic approach made it possible to describe mothers’ own perspectives and was an effective way to recruit people with a foreign background. More ethnographic research is needed from the perspective of children and adolescents with foreign backgrounds to make their voices heard as well.
  • Vähä-Mäkilä, Helena (Helsingin yliopisto, 2021)
    The human gastrointestinal track is populated by gut microbiota that consist of viruses, bacteria, archaea, fungi and micro-eukaryotes. The gut microbiota is beneficial for the host in many ways, including synthesis of short chain fatty acids and vitamins, and supporting the maturation and normal functions of the immune system. A healthy gut microbiota provides colonization resistance by preventing the attachment and growth of pathogenic microorganisms in the intestines. The use of antibiotics is a common cause of intestinal microbiota disturbation and weakened colonization resistance, which can lead to intestinal infection after antibiotic treatment. The leading cause of antibiotic-associated diarrhea is infection caused by bacterium Clostridioides difficile. C. difficile infection is generally treated with vancomycin or metronidazole, but in approximately 20 % of the patients the infection renewed. In these cases, the infection is referred to as a recurrent C. difficile infection. A recurrent C. difficile infection is treated with a repeated course of antibiotics or a fecal microbiota transplantation (FMT). FMT is a medical procedure in which feces of a healthy pre-screened donor is infused into a patient’s intestine in order to restore a healthy gut microbiota. FMT is an effective treatment for recurrent Clostridioides difficile infections, and its efficacy to treat other diseases linked with intestinal dysbiosis is being studied. Rectal bacteriotherapy, in which a transplant consists of specific intestinal bacterial strains, is used similarly to FMT, has been studied as a substitute for FMT to further reduce possible risks of fecal transplant such as transferring yet-unknown pathogens into patients. The gut microbiota is a favorable ecosystem for enrichment of antibiotic resistant genes through horizontal gene transfer between bacteria. From individuals carrying C. difficile bacteria not everyone will develop C. difficile infection after antibiotic treatment, and not all C. difficile infections lead to recurrent C. difficile infections. The reason for this might be the colonization resistance against C. difficile provided by the antibiotic resistant microbes that weren’t affected by the antibiotic treatment. Antibiotic resistant commensal bacteria living in the intestine may have an important role in maintaining the colonization resistance during and after antibiotic treatment. Since vancomycin is used as a treatment for C. difficile infections, introduction of non-pathogenic vancomycin resistant bacteria in form of bacteriotherapy could provide a better colonization resistance during the antibiotic treatment. The aim of this study was to examine the incidence of vancomycin resistance gene vanB in the microbiota of three FMT donors and 13 recipients, and to study culturable vancomycin resistant gut bacteria isolated from FMT donors. The vanB gene carriage of FMT donors and patients before and after FMT was studied. Furthermore, a total of 68 vancomycin resistant bacterial isolates were cultivated and purified from FMT donors, and the taxonomical identification of isolates was performed based on their 16S rRNA gene. Whether the vancomycin resistance of the isolates resulted from vanB gene was assessed using a PCR method. The results showed that all the FMT donors carried a vanB gene in their microbiota. The gene was present in the patients’ intestinal microbiota one month after FMT and half of the patients carried the gene still after 8 or 12 months after FMT. The vanB gene wasn’t found in the samples collected from patients before FMT. It is likely that the vanB gene had transferred from donors to patients via FMT. However, vanB gene couldn’t be detected in any of the cultivated bacterial isolates, and thus the bacterial strains carrying the gene were left unidentified. The isolates represented 21 different bacterial species. Donors differed from each other with respect to overall species distribution, which supports the previous findings of individual specific microbiotas. All three donors carried species from the genus Bacteroides and lately reclassified genus Lactobacillus, but none of the species was found in all three donors. The isolates found in this study might be candidate strains for rectal bacteriotherapy, but further studies are required to determine the effectiveness and safety of these isolates.
  • Nummela, Maria (Helsingin yliopisto, 2014)
    Campylobacter cause human campylobacteriosis, a gastroenteritis characterised by symptomps that range from abdominal pain to bloody diarrhea. The most common species behind human infections is Campylobavter jejuni, the infective dose of which has been recognized to be low. Warm-blooded animals are found to be common carriers of Campylobacter in their intestinal tract. As susceptible to environmental stress factors, Campylobacter is unable to multiply outside the host; it spreads to the environment through feces. Cattle has been recognised as an important reservoir of Campylobacter and raw milk the leading cause of Campylobacter outbreaks along with water and poultry. Most commonly, contamination of raw milk derive from fecal contamination during milking. The prevalence of Campylobacter was examined in three dairy farms, of which two, farms B and C, had faced an outbreak carried by raw milk right before the monitoring period of the study commenced. In the third farm A, Campylobacter hadn’t been detected either from raw milk or milk filters, and the prevalence in cattle was found to be low. Cattle were sampled 1-2 times and both milk as well as milk filter samples were obtained weekly during the monitoring period. Furthermore, environmental samples were collected. Samples were examined according to the modified NMKL 119:2007 cultivation method and MPN technique was used to quantify Campylobacter in raw milk samples. C. jejuni isolates were genotyped applying PFGE typing with SmaI enzyme. Moreover, concerning the hygienic control of raw milk, suitability of milk filters in detecting Campylobacter from bulk tank milk was examined in a shelf life experiment, in which milk filters were first divided in two parts, then spiked with four different concentrations of C. jejuni. In order to examine how well C. jejuni survives in storage conditions, spiked milk filters were packed into cool bags stored in room temperature for four different time intervals. Campylobacter was detected in cattle from all three dairy farms, yet the prevalence in control farm A was substantially lower than in the farms of the outbreak B and C, in which more than half of the cattle shed Campylobacter in feces. In farm A as well as farm C Campylobacter was not detected in milk or milk filters during the monitoring period. In outbreak farm C, the milk was most likely to be contaminated due to poor short-term milking hygiene conditions, as the C. jejuni genotype that most of the cattle shed proved to be identical with C. jejuni strain isolated from bulk tank milk during the investigation of the outbreak. Then again, outbreak farm B faced a rare, long-lasting Campylobacter contamination, as milk and milk filters were still found positive for Campylobacter six months after the outbreak. Up to 35 MPN / ml of Campylobacter was quantified from milk. The genotype detected from the milk and milk filters was dominant in the cattle as well. Nevertheless, the source of the contamination remained unclear and hadn’t been eliminated in time for the last sampling in spite of the satination and renovation operations made. Continous fecal contamination, biofilm harboured in the milking machine and direct extraction of Campylobacter to milk due to an udder infection were suspected as potential causes of the long-lasting contamination. In the shelf life experiment of milkfilters the background microflora, which was resistant to the selective supplement of Bolton Broth used in this study, proved a bigger problem for the detection of Campylobacter than its susceptibility to environmental stress. Accordingly, with the protocol used in this study, the experiences gained detecting the samples obtained from farm B suggest that milk is a superior sample matrix over milk filters.

View more