4 research outputs found
Effect of environmental enrichment and group size on behaviour and live weight in growing rabbits
No full text[EN] The aim of this research was to study the effects of group size and environmental enrichment on behaviour and growth of 108 hybrid growing rabbits (Oryctolagus cuniculus). We compared the behaviour (time budget and reactions to specific behavioural tests: "tonic immobility" and "emergence test") and live weight of growing rabbits housed in cages with a different number of rabbits per cage (2, 3 and 4; same density:14 rabbits/m2). Half of the cages were enriched with a wooden stick (Robinia Pseudoacacia, length: 20 cm ¿ diameter: 6 cm, cylindrical) hanging from the ceiling of the cage. The stick and number of animals per cage had no effect on weight gain or on behavioural tests responses. Interaction with the stick was significantly higher at the beginning of the growing period. Principal component analysis performed on the data for the whole period showed significant differences according to the treatments: increasing the number of rabbits per cage and introducing a wooden stick seemed to affect locomotor activity frequency and social interactions. Rabbits housed 3 and 4 per cage showed less lying behaviour and higher locomotor activity and sitting. The larger functional space allowance enabled rabbits to perform more natural behaviours compared to smaller cages (2 rabbits/cage). Environmental enrichment seems to be related to higher allogrooming behaviour frequency, which could indicate a social behaviour related to pheromonal olfactory stimulation and mutual recognition.Zucca, D.; Marelli, S.; Redaelli, V.; Heinzl, E.; Cardile, H.; Ricci, C.; Verga, M.... (2012). Effect of environmental enrichment and group size on behaviour and live weight in growing rabbits. World Rabbit Science. 20(2):89-95. https://doi.org/10.4995/wrs.2012.1082SWORD899520
In-air Tensile Load-strain Behaviour of HDPE Geogrids Under Cyclic Loading
No full textAbstractThe knowledge of geosynthetics mechanical behaviour under static and cyclic loads is important in order to develop constitutive models to be used in numerical analyses of geosynthetic reinforced structures.The paper describes a series of wide-width monotonic and multistage tensile tests on HDPE extruded uniaxial geogrids with different tensile stiffness. The cyclic tensile tests have been performed using a multistage procedure varying the pre-stress tensile load, the cyclic tensile loading amplitude and the frequency. The influence of these parameters on the residual strains (defined as the strain value when cyclic loads returns to the pre-stress load) has been analysed
Current concepts on oxidative/carbonyl stress, inflammation and epigenetics in pathogenesis of chronic obstructive pulmonary disease
No full textChronic obstructive pulmonary disease (COPD) is a global health problem. The current therapies for COPD are poorly effective and the mainstays of pharmacotherapy are bronchodilators. A better understanding of the pathobiology of COPD is critical for the development of novel therapies. In the present review, we have discussed the roles of oxidative/aldehyde stress, inflammation/immunity, and chromatin remodeling in the pathogenesis of COPD. An imbalance of oxidants/antioxidants caused by cigarette smoke and other pollutants/biomass fuels plays an important role in the pathogenesis of COPD by regulating redox-sensitive transcription factors (e.g., NF-κB), autophagy and unfolded protein response leading to chronic lung inflammatory response. Cigarette smoke also activates canonical/alternative NF-κB pathways and their upstream kinases leading to sustained inflammatory response in lungs. Recently, epigenetic regulation has been shown to be critical for the development of COPD because the expression/activity of enzymes that regulate these epigenetic modifications have been reported to be abnormal in airways of COPD patients. Hence, the significant advances made in understanding the pathophysiology of COPD as described herein will identify novel therapeutic targets for intervention in COPD
