Chemical capture of free-ranging red deer (Cervus elaphus) with medetomidine-ketamine

Seventeen free-ranging red deer (Cervus elaphus) (12 calves and 5 yearling hinds) were immobilized with a combination of medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) in winter (January-March). Immobilizations were performed with plastic projectile syringes fired from a dart gun. Mean (SD) doses of 0.147 (0.024) mg MED/kg and 2.5 (0.4) mg KET/kg induced recumbency in 5.0 (2.0) minutes in the calves and all of them were completely immobilized. The initial doses in the yearling hinds were 0.099 (0.016) mg MED/kg and 1.9 (0.2) mg KET/kg but three of them required addirional dosing for induction of reliable restraint. The distance covered by the animals between darting and recumbency ranged from 40-250 m for calves and 100-300 m for yearling hinds. The animals were translocated to deer farms for breeding purposes and were given 12.5-25.0 mg of atipamezole hydrochloride before transportation. All animals recovered completely. Haematological and serum biochemical comparisons between free-ranging calves immobilized with medetomidine-ketamine (n=3) and captive unmedicated calves (n=4) showed that chemical capture induce very little stress in red deer

A comparison of fragmenting lead-based and lead-free bullets for aerial shooting of wild pigs

In response to the health threats posed by toxic lead to humans, scavenging wildlife and the environment, there is currently a focus on transitioning from lead-based to lead-free bullets for shooting of wild animals. We compared efficiency metrics and terminal ballistic performance for lead-based and lead-free (non-lead) bullets for aerial shooting of wild pigs (Sus scrofa) in eastern Australia. Ballistic testing revealed that lead-based and lead-free bullets achieved similar performance in precision and muzzle kinetic energy (E-0) levels (3337.2 J and 3345.7 J, respectively). An aerial shooting trial was conducted with wild pigs shot with one type of lead-based and one type of lead-free bullets under identical conditions. Observations were made from 859 shooting events (n = 430 and 429 respectively), with a sub-set of pigs examined via gross post-mortem (n = 100 and 108 respectively), and a further sub-set examined via radiography (n = 94 and 101 respectively). The mean number of bullets fired per pig killed did not differ greatly between lead-based and lead-free bullets respectively (4.09 vs 3.91), nor did the mean number of bullet wound tracts in each animal via post-mortem inspection (3.29 vs 2.98). However, radiography revealed a higher average number of fragments per animal (median >300 vs median = 55) and a broader distribution of fragments with lead-based bullets. Our results suggest that lead-based and lead-free bullets are similarly effective for aerial shooting of wild pigs, but that the bullet types behave differently, with lead-based bullets displaying a higher degree of fragmentation. These results suggest that aerial shooting may be a particularly important contributor to scavenging wildlife being exposed to lead and that investigation of lead-free bullets for this use should continue

Metabolic reprogramming involving glycolysis in the hibernating brown bear skeletal muscle

Background: In mammals, the hibernating state is characterized by biochemical adjustments, which include metabolic rate depression and a shift in the primary fuel oxidized from carbohydrates to lipids. A number of studies of hibernating species report an upregulation of the levels and/or activity of lipid oxidizing enzymes in muscles during torpor, with a concomitant downregulation for glycolytic enzymes. However, other studies provide contrasting data about the regulation of fuel utilization in skeletal muscles during hibernation. Bears hibernate with only moderate hypothermia but with a drop in metabolic rate down to ~ 25% of basal metabolism. To gain insights into how fuel metabolism is regulated in hibernating bear skeletal muscles, we examined the vastus lateralis proteome and other changes elicited in brown bears during hibernation. Results: We show that bear muscle metabolic reorganization is in line with a suppression of ATP turnover. Regulation of muscle enzyme expression and activity, as well as of circulating metabolite profiles, highlighted a preference for lipid substrates during hibernation, although the data suggested that muscular lipid oxidation levels decreased due to metabolic rate depression. Our data also supported maintenance of muscle glycolysis that could be fuelled from liver gluconeogenesis and mobilization of muscle glycogen stores. During hibernation, our data also suggest that carbohydrate metabolism in bear muscle, as well as protein sparing, could be controlled, in part, by actions of n-3 polyunsaturated fatty acids like docosahexaenoic acid. Conclusions: Our work shows that molecular mechanisms in hibernating bear skeletal muscle, which appear consistent with a hypometabolic state, likely contribute to energy and protein savings. Maintenance of glycolysis could help to sustain muscle functionality for situations such as an unexpected exit from hibernation that would require a rapid increase in ATP production for muscle contraction. The molecular data we report here for skeletal muscles of bears hibernating at near normal body temperature represent a signature of muscle preservation despite atrophying conditions

Proteolysis inhibition by hibernating bear serum leads to increased protein content in human muscle cells

Muscle atrophy is one of the main characteristics of human ageing and physical inactivity, with resulting adverse health outcomes. To date, there are still no efficient therapeutic strategies for its prevention and/or treatment. However, during hibernation, bears exhibit a unique ability for preserving muscle in conditions where muscle atrophy would be expected in humans. Therefore, our objective was to determine whether there are components of bear serum which can control protein balance in human muscles. In this study, we exposed cultured human differentiated muscle cells to bear serum collected during winter and summer periods, and measured the impact on cell protein content and turnover. In addition, we explored the signalling pathways that control rates of protein synthesis and degradation. We show that the protein turnover of human myotubes is reduced when incubated with winter bear serum, with a dramatic inhibition of proteolysis involving both proteasomal and lysosomal systems, and resulting in an increase in muscle cell protein content. By modulating intracellular signalling pathways and inducing a protein sparing phenotype in human muscle cells, winter bear serum therefore holds potential for developing new tools to fight human muscle atrophy and related metabolic disorders

Heads in the sand: public health and ecological risks of lead-based bullets for wildlife shooting in Australia

Lead (Pb) is a toxic element banned from fuel, paint and many other products in most developed countries. Nonetheless, it is still widely used in ammunition, including rifle bullets, and Pb-based bullets are almost universally used in Australia. For decades, poisoning from Pb shot (shotguns) has been recognised as a cause of disease in waterfowl and Pb shot has been subsequently banned for waterfowl hunting in many jurisdictions. However, the risks posed by Pb-based bullets (rifles) have not been similarly recognised in Australia. Pb-based rifle bullets frequently fragment, contaminating the tissue of shot animals. Consuming this Pb-contaminated tissue risks harmful Pb exposure and, thus, the health of wildlife scavengers (carrion eaters) and humans and their companion animals who consume harvested meat (game eaters). In Europe, North America and elsewhere, the environmental and human health risks of Pb-based bullets are widely recognised, and non-toxic alternatives (e.g. copper-based bullets) are increasingly being used. However, Australia has no comparable research despite widespread use of shooting, common scavenging by potentially susceptible wildlife species, and people regularly consuming shot meat. We conclude that Australia has its collective ‘head in the sand’ on this pressing worldwide One Health issue. We present the need for urgent research into this field in Australia

Risk-taking by Eurasian lynx (Lynx lynx) in a human-dominated landscape: Effects of sex and reproductive status.

This study aimed to test how the sex and reproductive status of Eurasian lynx influenced their use of 'attractive sinks' - habitats with high prey density and high mortality risks. Locations of 24 Eurasian lynx Lynx lynx were obtained by radio-telemetry in a mixed forest and agricultural habitat in south-eastern Norway. Roe deer, the major food source of lynx in the study area, occurred at higher densities closer to areas of human activity and infrastructure. Proximity of lynx locations to human activity and infrastructure was used as a risk index because the most common causes of death among Scandinavian lynx were of anthropogenic origin. This study shows that distances from lynx locations to human activity were significantly greater for females with newborn kittens than for males, but this decreased with kitten age. The data suggest that this response to human activity is influenced by the reproductive strategies of males and females, and might explain male-biased human-induced mortality in this study and in carnivores more generally