Phaidra - University of Veterinary Medicine Vienna
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Modulation of ADAM17 Levels by Pestiviruses Is Species-Specific
No full textUpon host cell infection, viruses modulate their host cells to better suit their needs, including the downregulation of virus entry receptors. ADAM17, a cell surface sheddase, is an essential factor for infection of bovine cells with several pestiviruses. To assess the effect of pestivirus infection on ADAM17, the amounts of cellular ADAM17 and its presence at the cell surface were determined. Mature ADAM17 levels were reduced upon infection with a cytopathic pestivirus bovis (bovine viral diarrhea virus, cpBVDV), pestivirus suis (classical swine fever virus, CSFV) or pestivirus giraffae (strain giraffe), but not negatively affected by pestivirus L (Linda virus, LindaV). A comparable reduction of ADAM17 surface levels, which represents the bioactive form, could be observed in the presence of E2 of BVDV and CSFV, but not LindaV or atypical porcine pestivirus (pestivirus scrofae) E2. Superinfection exclusion in BVDV infection is caused by at least two proteins, glycoprotein E2 and protease/helicase NS3. To evaluate whether the lowered ADAM17 levels could be involved in superinfection exclusion, persistently CSFV- or LindaV-infected cells were challenged with different pestiviruses. Persistently LindaV-infected cells were significantly more susceptible to cpBVDV infection than persistently CSFV-infected cells, whilst the other pestiviruses tested were not or only hardly able to infect the persistently infected cells. These results provide evidence of a pestivirus species-specific effect on ADAM17 levels and hints at the possibility of its involvement in superinfection exclusion
Unexplored microbial diversity from 2,500 food metagenomes and links with the human microbiome
No full textComplex microbiomes are part of the food we eat and influence our own microbiome, but their diversity remains largely unexplored. Here, we generated the open access curatedFoodMetagenomicData (cFMD) resource by integrating 1,950 newly sequenced and 583 public food metagenomes. We produced 10,899 metagenome-assembled genomes spanning 1,036 prokaryotic and 108 eukaryotic species-level genome bins (SGBs), including 320 previously undescribed taxa. Food SGBs displayed significant microbial diversity within and between food categories. Extension to >20,000 human metagenomes revealed that food SGBs accounted on average for 3% of the adult gut microbiome. Strain-level analysis highlighted potential instances of food-to-gut transmission and intestinal colonization (e.g., Lacticaseibacillus paracasei) as well as SGBs with divergent genomic structures in food and humans (e.g., Streptococcus gallolyticus and Limosilactobabillus mucosae). The cFMD expands our knowledge on food microbiomes, their role in shaping the human microbiome, and supports future uses of metagenomics for food quality, safety, and authentication
Corrigendum: Comparative genomics of the Natural Killer Complex in carnivores
No full textNo abstract available
A simple method for repeated in vivo sperm collection from laboratory mice
No full textMouse spermatozoa for archiving laboratory mice or for in vitro fertilization (IVF) are routinely obtained from the cauda epididymis of adult males sacrificed for this purpose. To avoid the death of the donor, we tested whether a precisely timed interruption of the mating act could be used for repeated sperm collection from laboratory mice.Sperm donors (B6D2F1) were mated with a receptive female, and mating behavior was observed. The stud was separated from the female 1-2 s after the onset of the ejaculatory shudder. The ejected copulatory plug with the yellowish viscous ejaculate was carefully removed from the penile cup.A total of 80 ejaculates were successfully obtained from 100 ejaculations. The latency to first mount was 1.1 ± 1.1 min (mean ± SD) and to ejaculation 8.1 ± 4.7 min. The average number of mounts to ejaculation was 10.5 ± 5.8, and the mean number of spermatozoa per collected ejaculate was 1.86 ± 1.05 × 106. An average fertilization rate of 76% was observed after IVF.Separating the stud from the female just before ejaculation is feasible, easy to learn, and requires no special equipment. The sperm count of collected ejaculates is lower than natural ejaculations, but higher than previous in vivo sperm collection methods achieved. We recommend this simple sperm collection method in mice, especially when the donor cannot be sacrificed and/or repeated sperm collection from the same animal is required for experimental purposes
Silicone Shoes for the Treatment of Foot Pad Dermatitis (Bumblefoot) in Pet Chickens-A Retrospective Case Series
No full textBackyard chickens often suffer from foot pad dermatitis (FPD), a condition exacerbated by poor husbandry, nutritional deficiencies, and obesity. Pressure-relieving bandages, commonly used in the treatment of FPD, are impractical for outdoor chickens as they quickly become wet and dirty, necessitating daily changes that are often unfeasible. This retrospective study explores the use of custom-fit silicone shoes created via 3D-printed molds as an alternative to traditional bandages. CT scans were used to design shoes adapted from a design used for birds of prey. Over three years, 16 chickens with varying degrees of FPD were treated. The results demonstrated that silicone shoes were an effective treatment for FPD, allowing outdoor activity and facilitating daily lesion care without frequent bandage changes. The median shoe-wearing period was 14 days, and most owners provided positive feedback. Despite some attachment issues, the occurrence of secondary pressure marks, and feather regrowth challenges, the silicone shoes offered better ventilation, reusability, and consistent pressure relief compared to traditional bandages. This study concludes that silicone shoes are a viable solution for managing FPD in backyard chickens, promoting faster healing and improving owner compliance
Lockbox enrichment facilitates manipulative and cognitive activities for mice [Version 2]
No full textDue to the lack of complexity and variety of stimuli, conventional housing conditions of laboratory mice do not allow these animals to fully express their behavioral repertoire, including manipulative and cognitive activities. Therefore, we designed mechanical puzzles, so-called lockboxes, for mice that can be provided in their home cages. We investigated the impact of the lockbox enrichment on their phenotype and affective state when compared to conventional housing (CH) and super-environmental enrichment (SEE).Young adult female C57BL/6JCrl mice were examined before and after 2-month exposure to the different types of enrichment in a phenotyping test battery, including tests for trait and state anxiety-related behavior, calorimetric measurements, body weight measurements, the analysis of stress hormone metabolite concentrations, and sequential problem-solving abilities with a novel lockbox. At the end of the study, adrenal gland weights were determined and pathohistological evaluation was performed. For all continuous variables, the relative variability was calculated.While the different types of enrichment affected trait anxiety-related behavior, neither state anxiety-related behavior nor physiological variables (i.e., bodyweight, resting metabolic rate, stress hormone metabolite concentrations, adrenal gland weights) were influenced. LE improved sequential problem-solving (i.e., solving novel lockboxes) when compared to SEE. Regardless of the housing condition, the relative variability increased in most variables over time, although the coefficient of variation decreased for some variables, especially in animals with access to LE. There was no evidence of toxicopathological effects associated with the material from which the lockboxes were made.All lockboxes are available as open-source tool. LE revealed beneficial effects on the affective state of laboratory mice and their performance in solving novel lockboxes. Neither relevant phenotype of the mice nor reproducibility of the data were compromised by LE, similar to SEE. The lockboxes may also be used as novel approach for assessing cognition in mice
How relevant are sterols in the mode of action of prymnesins
No full textPrymnesins, produced by the haptophyte Prymnesium parvum, are considered responsible for fish kills when this species blooms. Although their toxic mechanism is not fully understood, membrane disruptive properties have been ascribed to A-type prymnesins. Currently it is suggested that pore-formation is the underlying cause of cell disruption. Here the hypothesis that A-, B-, and C-type prymnesins interact with sterols in order to create pores was tested. Prymnesin mixtures containing various analogs of the same type were applied in hemolysis and cytotoxicity assays using Atlantic salmon Salmo salar erythrocytes or rainbow trout RTgill-W1 cells. The hemolytic potency of the prymnesin types reflected their cytotoxic potential, with approximate concentrations reaching 50 % hemolysis (HC50) of 4 nM (A-type), 54 nM (C-type), and 600 nM (B-type). Variabilities in prymnesin profiles were shown to influence potency. Prymnesin-A (3 Cl) + 2 pentose + hexose was likely responsible for the strong toxicity of A-type samples. Co-incubation with cholesterol and epi-cholesterol pre-hemolysis reduced the potential by about 50 % irrespective of sterol concentration, suggesting interactions with sterols. However, this effect was not observed in RTgill-W1 toxicity. Treatment of RTgill-W1 cells with 10 µM lovastatin or 10 µM methyl-β-cyclodextrin-cholesterol modified cholesterol levels by 20-30 %. Regardless, prymnesin cytotoxicity remained unaltered in the modified cells. SPR data showed that B-type prymnesins likely bound with a single exponential decay while A-types seemed to have a more complex binding. Overall, interaction with cholesterol appeared to play only a partial role in the cytotoxic mechanism of pore-formation. It is suggested that prymnesins initially interact with cholesterol and stabilize pores through a subsequent, still unknown mechanism possibly including other membrane lipids or proteins
Long-Term Preclinical Evaluation of a Permanent Stent Developed for the Human Eustachian Tube
No full textThe Eustachian tube (ET) is a bottleneck when it comes to middle ear (ME) health. If its function is impaired, this can lead to serious consequences for the patient, such as hearing problems or deafness. Therefore, this study investigated a tapered nitinol stent (3-5 mm × 14 mm) for the human ET as a potential new permanent treatment for chronic Eustachian tube dysfunction (ETD) and thus ME ventilation disorders. The self-expanding stent was inserted unilaterally into the ET of 24 sheep with observation periods of 3, 6, and 12 months. Local tissue effects and the safety of the stent insertion were analyzed based on regular endoscopic checks, weekly tympanometry measurements, final imaging, and histological examinations. The animals showed no stent-related health restrictions. However, the individual anatomy and stenting procedure had an influence on the results. The tissue reaction in the endoscopic examinations was mild even though no concomitant antibiotics were administered. After all three monitoring periods, stented ETs had a significantly larger ET lumen than the non-stented contralateral ETs. However, tissue growth was detected in the stent. Overall, the first long-term study on an ET stent showed that the tapered ET stent could be a promising treatment option for ETD
Untersuchungen zum spontanen Gras-Aufnahme-Verhalten von Hunden und Katzen
No full textDiploma thesis - University of Veterinary Medicine Vienna - 2024This study investigated the factors influencing grass-eating behavior in cats and dogs. The factors examined included: age, gender, weight assessed by a veterinarian, daily exercise, illnesses, frequency of deworming, frequency of feeding per day, type of feeding (dry food, wet food, homemade rations), and frequency of food changes. This was conducted through a questionnaire survey published using LimeSurvey. Dog and cat owners was offered the opportunity to fill out the questionnaire for each of their pets. The results indicated that the following factors had no influence on the grass-eating behavior of the animals studied: gender, weight, exercise level, illnesses, frequency of feeding per day, and type of feeding. Age had an influence on dogs, with older dogs eating grass less frequently than younger ones. Whether this is related to naturally higher exposure to intestinal parasites in younger animals remains unclear. The frequency of deworming showed no correlation with grass-eating behavior in dogs. The more frequently dog food was changed, the less often dogs ate grass. This was an unexpected result since food changes have been associated with gastrointestinal discomfort, which is supposed to trigger grass-eating. When analyzing cats, they were divided into outdoor and indoor cats. Due to the small study population, no correlations could be found among indoor cats. In outdoor cats, the frequency of deworming influenced grass-eating behavior. The more frequently dewormed, the less often outdoor cats ate grass. In summary, age, deworming status, and feeding habits can influence grass-eating behavior. Further investigations are warranted in the future to reevaluate these factors and their impact with a larger study population and possibly under standardized housing conditions.Diplomarbeit - Veterinärmedizinische Universität Wien - 2024In dieser Arbeit wurde untersucht, welche Faktoren einen Einfluss auf das Gras-Fressen bei Katzen und Hunden haben. Die untersuchten Faktoren waren: Alter, Geschlecht, Körperkondition beurteilt durch einen Tierarzt, Bewegungspensum pro Tag, Krankheiten, Häufigkeit der Entwurmung, Häufigkeit der Fütterung pro Tag, Art der Fütterung (Trockenfutter, Nassfutter, selbstgemachte Rationen), Häufigkeit des Futterwechsels. Die Studie wurde als Fragebogenstudie konzipiert und mittels mittels Lime-Survey unter Hunde- und Katzenbesitzer:innen veröffentlicht. Hunde und Katzenbesitzer:innen hatten die Möglichkeit, den Fragebogen für jedes ihrer Haustiere einmal auszufüllen. Die Populationsgröße in dieser Studie waren 172 Hunde und 97 Katzen. Die Daten wurden mittels ordinal- logistischer Regressionsanalyse ausgewertet. Die Ergebnisse zeigten, dass folgende Faktoren keinen Einfluss auf das Gras-Fress-Verhalten, der untersuchten Tiere, haben: Geschlecht, Körperkondition, Bewegungspensum, Krankheiten, Häufigkeit der Fütterung pro Tag und die Art der Fütterung. Einen statistisch-gesicherten Einfluss bei Hunden hatte das Alter. Die älteren Hunde fressen Gras weniger häufig als jüngere Artgenossen. Ob das mit der natürlicherweise höheren Belastung mit intestinalen Parasiten bei jüngeren Tieren zusammenhängt, konnte direkt nicht untersucht werden. Die Ergebnisse der Auswertung zur Frage über die Entwurmungshäufigkeit zeigten jedoch, dass die Entwurmungshäufigkeit nicht in Zusammenhang mit dem Gras-Fress- Verhalten bei Hunden steht. Je öfter das Futter der Hunde gewechselt wird, desto weniger oft fressen die Hunde Gras. Dies war ein unerwartetes Ergebnis, da Futterwechsel mit Magen- Darm-Beschwerden in Zusammenhang gebracht werden und Magen-Darm-Beschwerden Gras- Fressen auslösen sollen. Bei der Analyse der Katzen wurde zwischen Freigänger und Wohnungskatzen unterschieden. Aufgrund der kleinen Studienpopulation konnten keine Zusammenhänge zwischen den gegebenen Faktoren und dem Gras-Fressen bei den Wohnungskatzen festgestellt werden. Bei Freigängern hat die Entwurmungshäufigkeit einen signifikanten Einfluss auf das Gras-FressVerhalten. Je öfter entwurmt wird, desto weniger oft fressen als Freigänger gehaltene Katzen Gras. Zusammenfassend kann gesagt werden, dass Alter, Entwurmungsstatus und Fütterung einen Einfluss auf das Gras-Fress-Verhalten haben können, jedoch zum Teil unterschiedlich bei Hunden und Katzen. Zukünftig sind weitere Untersuchungen indiziert, um diese Faktoren und ihre Auswirkung mit einer größeren Studienpopulation und eventuell unter standardisierten Haltungsbedingungen noch einmal zu prüfen