Effects of Cage Enrichment on Behavior, Welfare and Outcome Variability in Female Mice

The manner in which laboratory rodents are housed is driven by economics (minimal use of space and resources), ergonomics (ease of handling and visibility of animals), hygiene, and standardization (reduction of variation). This has resulted in housing conditions that lack sensory and motor stimulation and restrict the expression of species-typical behavior. In mice, such housing conditions have been associated with indicators of impaired welfare, including abnormal repetitive behavior (stereotypies, compulsive behavior), enhanced anxiety and stress reactivity, and thermal stress. However, due to concerns that more complex environmental conditions might increase variation in experimental results, there has been considerable resistance to the implementation of environmental enrichment beyond the provision of nesting material. Here, using 96 C57BL/6 and SWISS female mice, respectively, we systematically varied environmental enrichment across four levels spanning the range of common enrichment strategies: (1) bedding alone; (2) bedding + nesting material; (3) deeper bedding + nesting material + shelter + increased vertical space; and (4) semi-naturalistic conditions, including weekly changes of enrichment items. We studied how these different forms of environmental enrichment affected measures of animal welfare, including home-cage behavior (time–budget and stereotypic behavior), anxiety (open field behavior, elevated plus-maze behavior), growth (food and water intake, body mass), stress physiology (glucocorticoid metabolites in fecal boluses and adrenal mass), brain function (recurrent perseveration in a two-choice guessing task) and emotional valence (judgment bias). Our results highlight the difficulty in making general recommendations across common strains of mice and for selecting enrichment strategies within specific strains. Overall, the greatest benefit was observed in animals housed with the greatest degree of enrichment. Thus, in the super-enriched housing condition, stereotypic behavior, behavioral measures of anxiety, growth and stress physiology varied in a manner consistent with improved animal welfare compared to the other housing conditions with less enrichment. Similar to other studies, we found no evidence, in the measures assessed here, that environmental enrichment increased variation in experimental results

Biomechanics of speed adaptation and functionality of arm swing in cross-country skiing

Skiing technique has a major impact on cross-country (XC) skiing performance and helps the athlete to ski as fast or as economic as possible depending on what is asked in the specific race situation. Four studies have been conducted, aiming to investigate speed adaptation mechanism in arm swing assisted XC-skiing techniques (I, II), to determine if and how arm swing contributes to XC-skiing speed (II, IV) and propulsion (IV), putting special emphasis on accessing the centre of mass (COM) acceleration and to reveal from which push-off the gained acceleration originates (III, IV). Highly skilled XC-skiers participated in the experiments. While study I was conducted during double poling with kick (DPK) and roller skiing on a treadmill, the studies II-IV investigated leg skating and V2-alternate skating (V2A) during natural skiing on snow. The results (I) indicate that adapting to submaximal DPK speeds athletes increased cycle length and cycle rate, producing greater forces. Thereby athletes who increased cycle length more across speeds emphasised poling with short poling and long arm swing times rather than leg-action. Studies II and IV revealed that athletes skied considerable faster when using arm swing. They realised greater cycle length at high submaximal skiing speed, a pattern which has been described as performance characteristic. A neuromuscular effect of arm swing was detected (II) in high submaximal speed as greater forces have been produced with lower neuromuscular activation in knee extensor muscles. The position of COM could be accessed and validated (III). By estimating COM acceleration from force and position data, it was feasible to determine how much each push-off contributes to overall propulsion (II) and that the amount of gained propulsion changed due to arm swing use (IV). It should be emphasised that greater propulsion could be generated during arm swing assisted push-offs in maximal speeds and regardless if one or both arms were swinging (IV). Main reason for this was the greater forward lean of the athletes during push-off. The additional linear momentum of the swinging arms and the transfer of momentum from braking arms to the rest of the body contributed to greater gain of linear momentum during push-off in arm swing trials. A faster arm swing directed more forward and less upward at the end of push-off together with a “long arm” pattern added to compensate the disadvantage of less swinging mass in single arm swing. This study provided first insights how arm swing should be conducted in V2A. The detected mechanism of speed adaptation in arm swing assisted skiing techniques together with the beneficial effects of arm swing offer new possibilities for diagnostic and training and should be considered in theory based technique training.by Mag. Caroline GöpfertLiteraturverzeichnis: Blatt 101-112Paris Lodron University of Salzburg, Dissertation, 2017OeBB(VLID)497120

Pulmonary Echinococcus multilocularis metastasis in a dog.

A young adult Labrador retriever dog was presented for surgical debulking of hepatic alveolar echinococcosis. Computed tomography detected hepatomegaly with multiple large cavitary masses with extension of tissue from a lesion wall into the caudal vena cava and numerous nodules in all lung lobes. Following euthanasia, histology confirmed parasitic vesicles with granulomatous reaction in all lesions, and polymerase chain reaction (PCR) established the causative agent to be Echinococcus multilocularis. This report is the first to present imaging features of pulmonary E. multilocularis granulomata in a dog

Propulsion Calculated by Force and Displacement of Center of Mass in Treadmill Cross-Country Skiing

This study evaluated two approaches for estimating the total propulsive force on a skier’s center of mass (COM) with double-poling (DP) and V2-skating (V2) skiing techniques. We also assessed the accuracy and the stability of each approach by changing the speed and the incline of the treadmill. A total of 10 cross-country skiers participated in this study. Force measurement bindings, pole force sensors, and an eight-camera Vicon system were used for data collection. The coefficient of multiple correlation (CMC) was calculated to evaluate the similarity between the force curves. Mean absolute force differences between the estimated values and the reference value were computed to evaluate the accuracy of each approach. In both DP and V2 techniques, the force–time curves of the forward component of the translational force were similar to the reference value (CMC: 0.832–0.936). The similarity between the force and time curves of the forward component of the ground reaction force (GRF) and the reference value was, however, greater (CMC: 0.879–0.955). Both approaches can estimate the trend of the force–time curve of the propulsive force properly. An approach by calculating the forward component of GRF is a more appropriate method due to a better accuracy.peerReviewe

Serum phosphorylated tau protein 181 and neurofilament light chain in cognitively impaired heart failure patients

Background Chronic heart failure (HF) is known to increase the risk of developing Alzheimer’s dementia significantly. Thus, detecting and preventing mild cognitive impairment, which is common in patients with HF, is of great importance. Serum biomarkers are increasingly used in neurological disorders for diagnostics, monitoring, and prognostication of disease course. It remains unclear if neuronal biomarkers may help detect cognitive impairment in this high-risk population. Also, the influence of chronic HF and concomitant renal dysfunction on these biomarkers is not well understood. Methods Within the monocentric Cognition.Matters-HF study, we quantified the serum levels of phosphorylated tau protein 181 (pTau) and neurofilament light chain (NfL) of 146 extensively phenotyped chronic heart failure patients (aged 32 to 85 years; 15.1% women) using ultrasensitive bead-based single-molecule immunoassays. The clinical work-up included advanced cognitive testing and cerebral magnetic resonance imaging (MRI). Results Serum concentrations of NfL ranged from 5.4 to 215.0 pg/ml (median 26.4 pg/ml) and of pTau from 0.51 to 9.22 pg/ml (median 1.57 pg/ml). We detected mild cognitive impairment (i.e., T-score < 40 in at least one cognitive domain) in 60% of heart failure patients. pTau (p = 0.014), but not NfL, was elevated in this group. Both NfL (ρ = − 0.21; p = 0.013) and pTau (ρ = − 0.25; p = 0.002) related to the cognitive domain visual/verbal memory, as well as white matter hyperintensity volume and cerebral and hippocampal atrophy. In multivariable analysis, both biomarkers were independently influenced by age (T = 4.6 for pTau; T = 5.9 for NfL) and glomerular filtration rate (T = − 2.4 for pTau; T = − 3.4 for NfL). Markers of chronic heart failure, left atrial volume index (T = 4.6) and NT-proBNP (T = 2.8), were further cardiological determinants of pTau and NfL, respectively. In addition, pTau was also strongly affected by serum creatine kinase levels (T = 6.5) and ferritin (T = − 3.1). Conclusions pTau and NfL serum levels are strongly influenced by age-dependent renal and cardiac dysfunction. These findings point towards the need for longitudinal examinations and consideration of frequent comorbidities when using neuronal serum biomarkers