Phaidra - University of Veterinary Medicine Vienna
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Pilotstudie zur mikrobiellen Belastung von Gülleseparat als Einstreumaterial und zu den Auswirkungen auf die Besiedlung der Zitzenhaut mit potenziell euterpathogenen Bakterien
No full textDiplomarbeit - Veterinärmedizinische Universität Wien - 2024Im Rahmen dieser Diplomarbeit wurden die mikrobielle Belastung von Gülleseparat als Einstreumaterial und die Auswirkungen dieser Einstreu auf die Besiedelung der Zitzenhaut mit potenziell euterpathogenen Bakterien untersucht. Dazu wurden in einem oberösterreichischen Milchviehbetrieb mit 35 laktierenden Fleckviehkühen regelmäßig Viertelgemelksproben, Einstreuproben und Zitzenhauttupfer nach standardisierten Vorgaben entnommen und bakteriologisch untersucht. Anhand von Sammelproben aus je fünf Liegeboxen wurde weiters die Keimentwicklung in den Liegeboxen 24, 48 und 96 Stunden nach der Einbringung von frisch gepressten Güllefeststoffen untersucht und es wurde der Temperatur- Feuchtigkeitsindex gemessen und ausgewertet. Die Aufarbeitung und Auswertung der Proben erfolgte im Milchlabor der Universitätsklinik für Wiederkäuer an der Veterinärmedizinischen Universität. Dazu wurden alle Einstreuproben und die Zitzenhauttupfer (in viertelstarker Ringerlösung) in Verdünnungsschritten auf Selektivnährböden ausplattiert und die Gesamtkeimzahl, die Keimbelastung mit Coliformen, Staphylokokken, äskulinpositiven katalasenegativen Kokken sowie Enterokokken bestimmt. Für die weitere Spezifizierung der Bakterien wurden schließlich insgesamt 334 Isolate von verschiedenen Selektivnährböden zufällig ausgewählt und an der Klinik für Geflügel der Veterinärmedizinischen Universität Wien mittels Matrix-assisted Laser Desorption/Ionisation Time-of-flight-Massenspektrometrie (MALDI-ToF MS) bis auf Speziesebene identifiziert. In den Einstreuproben wurden weiters der Trockensubstanzgehalt bestimmt und der pH-Wert gemessen. In frisch gepressten Güllefeststoffen betrug die Gesamtkeimzahl bei der ersten Untersuchung im April 8,84 x 108 pro Gramm Trockensubstanz (g TS) bei der zweiten Messung im Juni 6,21 x 108 pro g TS, während die Anzahl an Coliformen bei 9,64 x 105 pro g TS (April bzw. bei 6,77 x 105 pro g TS (Juni) lag. Die Keimzahlen der Enterokokken pro g TS lagen im April bei 6,43 x 105 und im Juni bei 4,51 x 105 pro g TS. Weitere Untersuchungen dieser Arbeit zeigten, dass der Trockensubstanzgehalt im Vergleich zum frisch gepressten Gülleseparat nach dem Einbringen in die Liegeboxen sinkt, während der pH- Wert im Vergleich zur frisch gepressten Einstreu alkalischer wird. Die Gesamtkeimzahl der Sammelproben aus den Liegeboxen war zum Zeitpunkt der Entnahme 0 (=frisch) am niedrigsten und zeigte den höchsten Anstieg nach 24 Stunden. Bei der Untersuchung der Zitzentupfer war auffällig, dass an der Zitzenspitze deutlich höhere Keimzahlen gemessen wurden als pro cm2 Zitzenhaut. Die Spezifizierung der Bakterien mittels MALDI-ToF MS führte zum Nachweis von mastitisrelevanten Bakterien (vor allem von E. coli, Klebsiella spp. und Enterococcus spp.) sowohl in der Einstreu als auch auf der Zitzenhaut.This diploma thesis investigated the microbial load of manure solids used as bedding material and the effects of this bedding on the colonization of the teat skin with mastitis pathogens. Quarter milk samples, bedding samples and teat skin swabs were regularly collected aseptically in an Austrian dairy farm with 35 lactating cows that were housed in a free stall barn with recycled manure solids as a bedding material in the cubicles. Pooled samples from five cubicles each were used to analyze bacterial development in the cubicles 24, 48 and 96 hours after spreading of freshly pressed manure solids. The temperature-humidity index was measured and analyzed concurrently. All samples were analyzed in the diagnostic laboratory of the University Clinic for Ruminants at the University of Veterinary Medicine. Bedding samples and teat skin swabs (in quarter-strength Ringer\u27s solution) were plated on selective culture media in dilution steps and the total bacterial count, the bacterial load with coliforms, staphylococci, catalase-negative cocci and enterococci were determined. Subsequently, 334 isolates from various selective culture media were randomly selected for further specification on selective culture media. Species identification was achieved using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) at the Poultry Clinic of the University of Veterinary Medicine, Vienna. Additionally, dry matter content and pH value were determined in the bedding samples. In freshly pressed manure solids, the total bacterial count in the first test in April was 8.84 x 108 per gramm dry matter (per g DM) and 6.21 x 108 per g DM the second test in June, while the coliform count was 9.64 x 105 per g DM (April) and 6.77 x 105 per g DM (June). The bacterial load of enterococci was 6.43 x 105 in April and 4.51 x 105 per g DM in June. Further investigations revealed a decrease in dry matter content and an increase in pH value after the introduction into the cubicles compared to freshly pressed manure solids. The total bacterial count of pooled samples from the cubicles was lowest at collection time 0 (= fresh) and showed the highest increase after 24 hours. Analysis of the teat swabs indicated significantly higher bacterial counts at the teat tip than per cm2 of teat skin. Bacterial specification using MALDIToF MS identified mastitis-relevant bacteria (E. coli, Klebsiella spp., Enterococcus spp.) both in the bedding and on the teat skin
Tracing the distribution of Icelandic stallions on the basis of pedigree and Y-chromosomal information
No full textDiplomarbeit - Veterinärmedizinische Universität Wien - 2024Als Pferde vor 4.200 Jahren domestiziert wurden, züchtete der Mensch sie nach seinen Bedürfnissen, und im Laufe der Zeit entwickelten sich die verschiedenen heute bekannten Pferderassen. Mithilfe von Y-chromosomalen Markern kann die väterliche Zuchtgeschichte von Pferden rekonstruiert werden. In vorangegangenen Studien wurde gezeigt, dass die meisten Rassen der sogenannten „Krongruppe“ zugeordnet werden können. Nur einige wenige Rassen wurden außerhalb der „Krongruppe“ eingeordnet, das Islandpferd ist eine von ihnen. Bisherige Ergebnisse zeigten, dass kein kürzlicher Einfluss von anderen modernen Pferderassen im Islandpferd nachzuweisen ist. Diese Aussage sollte in dieser Arbeit überprüft werden, des Weiteren sollte analysiert werden, ob bisherige Studien die gesamte Islandpferde Population abdeckten, oder ob es Sublinien dieser Rasse gibt, welche nicht genotypisiert wurden. Daher wurden Proben für die Y-chromosomale Genotypisierung nach ihrer Abstammung ausgewählt. Die Ergebnisse bestätigten die frühere Aussage, dass nur isländisch-spezifische Y-chromosomale Haplotypen im Islandpferd zu finden sind. Von 12.896 inkludierten Hengsten aus der Datenbank, welche die aktuelle Hengstpopulation abdeckt, konnten für 96,6 % Haplotypen zugeordnet werden. Darüber hinaus wurden die bereits bekannten Daten aus WorldFengur verwendet, um die Verteilung der aktuellen isländischen Hengstpopulation zu veranschaulichen und um festzustellen, ob verschiedene Sublinien in verschiedenen Ländern beliebter sind. Wie erwartet, waren die Sublinien in den einzelnen Ländern gleich verteilt, und in keinem Land wurde eine vorherrschende Sublinie gefunden. Im Weiteren, zeigten die Daten, dass die meisten Hengste in Island geboren wurden, obwohl sich die meisten Hengste derzeit außerhalb Islands befinden. Diese Studie zeigte, dass ein Einfluss von den modernen Pferderassen im Islandpferd weiterhin ausgeschlossen werden kann und zeigte des Weiteren den aktuellen Stand der weltweiten Verteilung der Islandpferde Hengste.Diploma thesis - University of Veterinary Medicine Vienna - 2024When horses were domesticated 4,200 years ago, humans bred them according to their needs, and different breeds evolved over time. With the use of Y-chromosomal markers, the paternal breeding history of horses can be reconstructed. In previous studies, most breeds clustered together into the so called ‘crown group’ of the phylogenetic tree, with only some breeds located outside the crown. The Icelandic horse is one of them. As previous studies showed that the Icelandic horse had no recent influences of modern breeds, we investigated whether this statement was true for the entire stallion population or if certain sublines were missed. Using pedigree information, a fine-scaled Y-chromosomal analysis was conducted. The results verified the previous statement that only Icelandic-specific Y-chromosomal haplotypes can be found in the Icelandic horse. From 12,896 observed stallions, haplotypes could be assigned for 96.6 % of them. Furthermore, the available data extracted from WorldFengur were used to illustrate the distribution of the current Icelandic stallion population and to observe if different sublines are more popular in different countries. As expected, the distribution of sublines throughout countries was fairly even, with no predominant subline in any country. Interestingly, data showed that even though most stallions are currently located outside Iceland, the majority of stallions are born in Iceland. Overall, we verified the absence of modern horse breeds within Icelandic horses and demonstrated the current state of the worldwide distribution of Icelandic stallions
Empirical and model-based evidence for a negligible role of cattle in peste des petits ruminants virus transmission and eradication
No full textPeste des petits ruminants virus (PPRV) is a multi-host pathogen with sheep and goats as main hosts. To investigate the role of cattle in the epidemiology of PPR, we simulated conditions similar to East African zero-grazing husbandry practices in a series of trials with local Zebu cattle (Bos taurus indicus) co-housed with goats (Capra aegagrus hircus). Furthermore, we developed a mathematical model to assess the impact of PPRV-transmission from cattle to goats. Of the 32 cattle intranasally infected with the locally endemic lineage IV strain PPRV/Ethiopia/Habru/2014 none transmitted PPRV to 32 co-housed goats. However, these cattle or cattle co-housed with PPRV-infected goats seroconverted. The results confirm previous studies that cattle currently play a negligible role in PPRV-transmission and small ruminant vaccination is sufficient for eradication. However, the possible emergence of PPRV strains more virulent for cattle may impact eradication. Therefore, continued monitoring of PPRV circulation and evolution is recommended
Characterization of a Syngeneic Orthotopic Model of Cholangiocarcinoma by [18F]FDG-PET/MRI
No full textCholangiocarcinoma (CCA) is a type of primary liver cancer originating from the biliary tract epithelium, characterized by limited treatment options for advanced cases and low survival rates. This study aimed to establish an orthotopic mouse model for CCA and monitor tumor growth using PET/MR imaging. Murine CCA cells were implanted into the liver lobe of male C57BL/6J mice. The imaging groups included contrast-enhanced (CE) MR, CE-MR with static [18F]FDG-PET, and dynamic [18F]FDG-PET. Tumor volume and FDG uptake were measured weekly over four weeks. Early tumor formation was visible in CE-MR images, with a gradual increase in volume over time. Dynamic FDG-PET revealed an increase in the metabolic glucose rate (MRGlu) over time. Blood analysis showed pathological changes in liver-related parameters. Lung metastases were observed in nearly all animals after four weeks. The study concludes that PET-MR imaging effectively monitors tumor progression in the CCA mouse model, providing insights into CCA development and potential treatment strategies
Deregulation of Metalloproteinase Expression in Gray Horse Melanoma Ex Vivo and In Vitro
No full textThe ability of human melanoma cells to switch from an epithelial to a mesenchymal phenotype contributes to the metastatic potential of disease. Metalloproteinases (MPs) are crucially involved in this process by promoting the detachment of tumor cells from the primary lesion and their migration to the vasculature. In gray horse melanoma, epithelial-mesenchymal transition (EMT) is poorly understood, prompting us to address MP expression in lesions versus intact skin by transcriptome analyses and the immunofluorescence staining (IF) of gray horse tumor tissue and primary melanoma cells. RNAseq revealed the deregulation of several MPs in gray horse melanoma and, notably, a 125-fold upregulation of matrix metalloproteinase 1 (MMP1) that was further confirmed by RT-qPCR from additional tumor material. The IF staining of melanoma tissue versus intact skin for MMP1 and tumor marker S100 revealed MMP1 expression in all lesions. The co-expression of S100 was observed at different extents, with some tumors scoring S100-negative. The IF staining of primary tumor cells explanted from the tumors for MMP1 showed that the metalloproteinase is uniformly expressed in the cytoplasm of 100% of tumor cells. Overall, the presented data point to MP expression being deregulated in gray horse melanoma, and suggest that MMP1 has an active role in gray horse melanoma by driving EMT-mediated tumor cell dissemination via the degradation of the extracellular matrix. Whilst S100 is considered a reliable tumor marker in human MM, gray horse melanomas do not seem to regularly express this protein
Lack of TYK2 signaling enhances host resistance to Candida albicans skin infection
No full textAbstract: Candida albicans is the most common human fungal pathogen, causing diseases ranging from local to life-threating systemic infections. Tyrosine kinase 2 (TYK2), a crucial mediator in several cytokine signaling pathways, has been associated with protective functions in various microbial infections. However, its specific contribution in the immune response to fungal infections has remained elusive. In this study, we show that mice lacking TYK2 or its enzymatic activity exhibit enhanced resistance to C. albicans skin infections, limiting fungal spread and accelerating wound healing. Impaired TYK2-signaling prompted the formation of a distinctive layer of necrotic neutrophils around the fungal pathogens. Transcriptomic analysis revealed TYK2\u27s pivotal role in regulating interferon-inducible genes in neutrophils, thereby impacting their antifungal capacity during infection. Furthermore, we show that TYK2-dependent interferon-gamma (IFN?) production contributes to fungal dissemination from the skin to the kidneys. Our study uncovers a hitherto unrecognized detrimental role of TYK2 in cutaneous C. albicans infections
Lethal versus surviving sepsis phenotypes displayed a partly differential regional expression of neurotransmitters and inflammation and did not modify the blood-brain barrier permeability in female CLP mice
No full textSeptic encephalopathy is frequent but its pathophysiology is enigmatic. We studied expression of neurotransmitters, inflammation and integrity of the blood-brain barrier (BBB) in several brain regions during abdominal sepsis. We compared mice with either lethal or surviving phenotype in the first 4 sepsis days. Mature CD-1 females underwent cecal ligation and puncture (CLP). Body temperature (BT) was measured daily and predicted-to-die (within 24 h) mice (for P-DIE; BT??35 °C), and healthy controls (CON). Brains were dissected into neocortex, cerebellum, midbrain, medulla, striatum, hypothalamus and hippocampus.CLP mice showed an up to threefold rise of serotonin in the hippocampus, 5-hydroxyindoleacetic and homovanillic acid (HVA) in nearly all regions vs. CON. Compared to P-SUR, P-DIE mice showed a 1.7 to twofold rise of HVA (386 ng/g of tissue), dopamine (265 ng/g) and 3,4-Dihydroxyphenylacetic acid (DOPAC; 140 ng/g) in the hippocampus, hypothalamus and medulla (174, 156, 82 ng/g of tissue, respectively). CLP increased expression of TNF?, IL-1? and IL-6 mRNA by several folds in the midbrain, cerebellum and hippocampus versus CON. The same cytokines were further elevated in P-DIE vs P-SUR in the midbrain and cerebellum. Activation of astrocytes and microglia was robust across regions but remained typically phenotype independent. There was a similar influx of sodium fluorescein across the BBB in both P-DIE and P-SUR mice.Compared to survivors, the lethal phenotype induced a stronger deregulation of amine metabolism and cytokine expression in selected brain regions, but the BBB permeability remained similar regardless of the predicted outcome
Going back to "basics": Harlow\u27s learning set task with wolves and dogs
No full textTo survive and reproduce, animals need to behave adaptively by adjusting their behavior to their environment, with learning facilitating some of these processes. Dogs have become a go-to model species in comparative cognition studies, making our understanding of their learning skills paramount at multiple levels, not only with regards to basic research on their cognitive skills and the effects of domestication, but also with applied purposes such as training. In order to tackle these issues, we tested similarly raised wolves and dogs in a serial learning task inspired by Harlow\u27s "learning set." In Phase 1, different pairs of objects were presented to the animals, one of which was baited while the other was not. Both species\u27 performance gradually improved with each new set of objects, showing that they "learnt to learn," but no differences were found between the species in their learning speed. In Phase 2, once subjects had learned the association between one of the objects and the food reward, the contingencies were reversed and the previously unrewarded object of the same pair was now rewarded. Dogs\u27 performance in this task seemed to be better than wolves\u27, albeit only when considering just the first session of each reversal, suggesting that the dogs might be more flexible than wolves. Further research (possibly with the aid of refined methods such as computer-based tasks) would help ascertain whether these differences between wolves and dogs are persistent across different learning task
No evidence for inequity aversion in non-human animals: a meta-analysis of accept/reject paradigms
No full textDisadvantageous inequity aversion (IA), a negative response to receiving less than others, is a key building block of the human sense of fairness. While some theorize that IA is shared by species across the animal kingdom, others argue that it is an exclusively human evolutionary adaptation to the selective pressures of cooperation among non-kin. Essential to this debate is the empirical question of whether non-human animals are averse towards unequal resource distributions. Over the past two decades, researchers have reported that individuals from a wide range of taxa exhibit IA; tasks where participants can reject or accept a given distribution of rewards delivered the bulk of this evidence. Yet these results have been questioned on both conceptual and empirical grounds. In the largest empirical investigation of non-human IA to date, we synthesize the primary data from 23 studies using accept/reject tasks, covering 60 430 observations of 18 species. We find no evidence for IA in non-human animals in these tasks. This finding held across all species in the dataset and pre-registered subsets (all species reported to exhibit IA, primates reported to exhibit IA, chimpanzees and capuchin monkeys). Alternative interpretations of the data and implications for the evolution of fairness are discussed
Influence of biosecurity on the occurrence of various enteric viruses in broiler flocks
No full textCommon enteric viruses affecting commercial broiler flocks include fowl adenovirus (FAdV), chicken parvovirus (ChPV), chicken astrovirus (CAstV), avian reovirus (ARV) and avian rotavirus (AvRV). To investigate their prevalence and to identify single and multiple infections we collected intestinal samples from 49 Austrian broiler flocks during necropsy of dead-on-farm birds twice during a production cycle (7–14 days and 28–35 days). Altogether, up to three consecutive clinically healthy flocks without signs of gastrointestinal disease were sampled from 17 different farms. Samples were analysed using virus isolation and PCR/RT–PCR methods. Virus prevalence was correlated with production data and on-farm biosecurity and management practices. Overall, ARV (75%) was most commonly detected in the flocks, followed by CAstV (61%), ChPV (61%), FAdV (57%) and AvRV (8%). Only in three (6%) flocks were none of the investigated enteric viruses detected. Flock infection profiles were very heterogeneous and included individual detection of the investigated viruses as well as different combinations thereof (up to all five investigated viruses). Even in the absence of clinical diarrhoea and/or macroscopic intestinal lesions, statistical analysis confirmed that the number of viruses detected had a significant economic impact characterised by poor weight gain and increased mortality, particularly due to the presence of FAdV, CAstV and/or ARV. Furthermore, the use of barn-specific clothing and/or footbaths as well as regular vermin control, resulted in lower prevalence of enteric viruses in the flocks studied. This highlights the importance of common biosecurity measures in poultry production to prevent economic losses