Phaidra - University of Veterinary Medicine Vienna
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Characterization of dynamic compliance of the respiratory system in healthy anesthetized dogs
No full textIn clinical practice, evaluating dynamic compliance of the respiratory system (Cdyn) could provide valuable insights into respiratory mechanics. Reference values of Cdyn based on body weight have been reported, but various factors may affect them and the evidence is scanty. This study aimed to establish a reference interval for Cdyn and identify associated variables.Data were collected from 515 client-owned dogs requiring anesthesia, excluding those with lower airway disease. The dogs were anesthetized, the tracheas intubated, and lungs ventilated at clinicians\u27 discretion across 11 centers in six countries, with no restrictions on anesthesia protocols or ventilation settings, except avoiding inspiratory pauses. Three Cdyn measurements from three consecutive breaths per dog were recorded using a standardized form, which also documented factors affecting Cdyn identified through literature and an online survey. Various spirometry technologies were used. The substantial variance in Cdyn measurements led to a comprehensive analysis using a multiple linear regression model. Multicollinearity (variables highly correlated with
each other) was addressed by investigating, transforming, or excluding factors. Initial simple linear regression assessed each variable\u27s individual effect on Cdyn, followed by a multiple linear regression model constructed via stepwise forward selection and backward elimination.The best-fitting model identified a linear relationship between Cdyn and body mass when the following conditions were met: high BCS (Body Condition Score), orotracheal tubes 80%) exposure for more than 10 minutes before Cdyn measurement. In cases where these conditions were not met, additional factors needed to be incorporated into the model. Low (1/9, 2/9, 3/9) and medium (4/9, 5/9) BCS, an orotracheal tube of the predicted size or larger and longer inspiratory times were associated with increased Cdyn. The use of alternative spirometry sensors, including Ped-lite, or prolonged exposure to high FIO2 levels resulted in decreased Cdyn.Establishing a reference interval for Cdyn proved challenging. A single reference interval may be misleading or unhelpful in
clinical practice. Nevertheless, this study offers valuable insights into the factors affecting Cdyn in healthy anesthetized dogs, which should be considered in clinical assessments
Immunohistochemical Staining Properties of Osteopontin and Ki-67 in Feline Meningiomas
No full textThe high recurrence rate of feline meningioma despite the generally benign histomorphology warrants additional markers of clinical aggressiveness. The Ki-67 index is commonly used as prognostic marker for meningioma recurrence in people. Osteopontin (OPN) is a protein involved in tumor progression and may be a potential malignancy marker. To date, osteopontin expression has not been investigated in feline meningioma. The aim of this study was to evaluate the extent of Ki-67 and osteopontin immunostaining of feline meningioma and to find possible associations with WHO (World Health Organization) grades and subtypes. Fifty-three feline meningioma samples were graded according to the human WHO classification and underwent immunohistochemical examination for Ki-67 and OPN. Fifty samples were classified as WHO grade I and three as WHO grade II. The mean Ki-67 ratio was 9.19 ± 9.47. Osteopontin expression was correspondingly high with a mean OPN IHC score of 150.17 (0-242.8), and a median Allred score of 7 (0-8). There was no significant correlation with Ki-67 index, osteopontin expression, WHO grades, or subtypes. The overall high expressions of osteopontin and Ki-67 may help explain the tendency for recurrence of feline meningioma. The human WHO grading system may not be sufficient to accurately estimate the clinical behavior of meningioma in this species
Sex differences in the relationship between maternal and foetal glucocorticoids in a free-ranging large mammal
No full textMaternal phenotypes can have long-term effects on offspring phenotypes. These maternal effects may begin during gestation, when maternal glucocorticoid (GC) levels may affect foetal GC levels, thereby having an organizational effect on the offspring phenotype. Recent studies have showed that maternal effects may be different between the sexes. However, how maternal GC levels relate to foetal levels is still not completely understood. Here we related, for the first time in a free-ranging large mammal, the fallow deer ( Dama dama), maternal GC levels with foetal in utero GC levels. We did this in a non-invasive way by quantifying cortisol metabolites from faecal samples collected from pregnant does during late gestation, as proxy for maternal GC level. These were then related to GC levels from hair of their neonate offspring (n = 40). We have shown that maternal GC levels were positively associated with foetal GC levels, but only in female offspring. These findings highlight sex differences, which may have evolved to optimize male growth at the cost of survival
Breast cancer survival prediction using an automated mitosis detection pipeline
No full textMitotic count (MC) is the most common measure to assess tumor proliferation in breast cancer patients and is highly predictive of patient outcomes. It is, however, subject to inter- and intraobserver variation and reproducibility challenges that may hamper its clinical utility. In past studies, artificial intelligence (AI)-supported MC has been shown to correlate well with traditional MC on glass slides. Considering the potential of AI to improve reproducibility of MC between pathologists, we undertook the next validation step by evaluating the prognostic value of a fully automatic method to detect and count mitoses on whole slide images using a deep learning model. The model was developed in the context of the Mitosis Domain Generalization Challenge 2021 (MIDOG21) grand challenge and was expanded by a novel automatic area selector method to find the optimal mitotic hotspot and calculate the MC per 2?mm2. We employed this method on a breast cancer cohort with long-term follow-up from the University Medical Centre Utrecht (N?=?912) and compared predictive values for overall survival of AI-based MC and light-microscopic MC, previously assessed during routine diagnostics. The MIDOG21 model was prognostically comparable to the original MC from the pathology report in uni- and multivariate survival analysis. In conclusion, a fully automated MC AI algorithm was validated in a large cohort of breast cancer with regard to retained prognostic value compared with traditional light-microscopic MC
What we (don\u27t) know about parrot welfare: Finding welfare indicators through a systematic literature review
No full textParrots are popular companion animals but show prevalent and at times severe welfare issues. Nonetheless, there are no scientific tools available to assess parrot welfare. The aim of this systematic review was to identify valid and feasible outcome measures that could be used as welfare indicators for companion parrots. From 1,848 peer-reviewed studies retrieved, 98 met our inclusion and exclusion criteria (e.g. experimental studies, captive parrots). For each outcome collected, validity was assessed based on the statistical significance reported by the authors, as other validity parameters were rarely provided for evaluation. Feasibility was assigned by considering the need for specific instruments, veterinary-level expertise or handling the parrot. A total of 1,512 outcomes were evaluated, of which 572 had a significant P-value and were considered feasible. These included changes in behaviour (e.g. activity level, social interactions, exploration), body measurements (e.g. body weight, plumage condition) and abnormal behaviours, amongst others. Many physical and physiological parameters were identified that either require experimental validation, or veterinary-level skills and expertise, limiting their potential use by parrot owners themselves. Moreover, a high risk of bias undermined the internal validity of these outcomes, while a strong taxonomic bias, a predominance of studies on parrots in laboratories, and an underrepresentation of companion parrots jeopardised their external validity. These results provide a promising starting point for validating a set of welfare indicators in parrots
Site Matters: Differences in Gene Expression Profiles Along the Bovine Rumen Papilla During Subacute Rumen Acidosis
No full textSubacute rumen acidosis (SARA) is a significant concern in dairy cattle fed grain-rich diets. To elucidate the underlying pathophysiological mechanisms, ruminal papilla biopsies are often used. This study aimed to assess how the sampling site along the ruminal papilla influences gene expression profiles in rumen epithelium during SARA. Rumen biopsies from five ruminal-cannulated non-lactating Holstein cows were collected during feeding of a forage diet (FD) and seven (wk1) and 21 days (wk3) after transition to high-grain (HG) feeding. Gene expression in apical (AP), basal (BP), and total length (TP) papillae were compared using RT-qPCR. Significant diet-induced effects were observed in AP for DSG1 (wk3, p = 0.0317), ZO1 (wk1 and wk3, p = 0.0159), GLUT3 (wk3, p = 0.0159), TLR4 (wk3, p = 0.0635), and NFKB (wk1, p = 0.0159), but hardly in BP or TP. Within wk1, TP showed higher transcript levels of ZO1 and TLR4 (p = 0.0079) and SGLT1 (p = 0.0317) compared to AP and BP independently from diet effects. These findings suggest that the apical parts of rumen papillae biopsies are most suitable for gene expression analyses to investigate diet-induced effects on rumen physiology and underscore the importance of considering the sampling site for accurate gene expression studies in rumen epithelium during SARA, providing valuable insights for future research and diagnostic approaches in managing rumen health in dairy cattle
Does the stress axis mediate behavioural flexibility in a social cichlid, Neolamprologus pulcher?
No full textAbstract: Behavioural flexibility plays a major role in the way animals cope with novel situations, and physiological stress responses are adaptive and highly efficient mechanisms to cope with unpredictable events. Previous studies investigating the role of stress responses in mediating behavioural flexibility were mostly done in laboratory rodents using stressors and cognitive challenges unrelated to the ecology of the species. To better understand how stress mediates behavioural flexibility in a natural context, direct manipulations of the stress response and cognitive tests in ecologically relevant contexts are needed. To this aim, we pharmacologically blocked glucocorticoid receptors (GR) in adult Neolamprologus pulcher using a minimally invasive application of a GR antagonist. GR blockade prevents the recovery after a stressful event, which we predicted to impair behavioural flexibility. After the application of the GR antagonist, we repeatedly exposed fish to a predator and tested their behavioural flexibility using a detour task, i.e. fish had to find a new, longer route to the shelter when the shortest route was blocked. While the latencies to find the shelter were not different between treatments, GR blocked fish showed more failed attempts during the detour tasks than control fish. Furthermore, weak performance during the detour tasks was accompanied by an increase of fear related behaviours. This suggests that blocking GR changed the perception of fear and resulted in an impaired behavioural flexibility. Therefore, our results support a potential link between the capacity to recover from stressors and behavioural flexibility in N. pulcher with potential consequences for an effective and adaptive coping with changing environments
Nutritional Considerations of Plant-Based Diets for People With Food Allergy
No full textPlant-based diets (PBD) have been reported throughout history, but are increasingly common in current times, likely in part due to considerable emphasis on climate change and human health and wellness. Many dietary organisations around the world endorse well-planned, nutritionally adequate PBD, which exclude some or all forms of animal-based foods. However, special attention must be given to patients who follow PBD and also have food allergy (FA), as avoidance may increase the risk of developing nutritional deficiencies, including poor growth in children, weight loss in adults and vitamin and mineral deficiencies. Given the increasing prevalence of both PBD and food allergen avoidance diets, healthcare providers are likely to counsel patients with FA who also follow a PBD. In this review, an overview of PBD in patients with FA is provided, including recent trends, macro- and micronutrient needs, and growth for children and weight gain considerations for adults. With regard to a PBD, special attention should be given to ensure adequate fat and protein intake and improving the bioavailability of several minerals such as iron, zinc, iodine, calcium and magnesium, and vitamins such as A, B2, B12 and D. Although the collective data on growth amongst children following a PBD are varied in outcome and may be influenced in part by the type of PBD, growth must be regularly monitored and in adults weight gain assessed as part of any clinical assessment in those people with FA
