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Stress and Capture Myopathy in Hares
07 July 2004 Special report highlighting capture myopathy, a stress-induced condition which has been identified as posing a threat to the hare species. Hares captured from the wild and used in coursing are among the animals most at risk. Capture myopathy (also known as post-capture myopathy, stress myopathy and transport myopathy) is a little-studied condition that has been recognised in a number of wild animals and domestic rabbits. In recent years some work has been carried out in the context of hunting and coursing, where the use of dogs or snares cause high levels of trauma before death or capture. There is now compelling evidence that the well-being of hares, and ultimately their survival, is compromised by capture, handling and transport. Definitions Welfare of an animal has been defined as "its state as regards its attempts to cope with its environment" (Broom 1986; Broom & Johnson 1993). Thus welfare refers to the state of an animal at a specific time and can be good or poor irrespective of what people think about the moral or ethical use of the animal concerned. If the individual is having difficulty in coping with its environment, or is failing to cope, then its welfare is poor (Broom & Johnson 1993; Broom 1996). Since this definition of welfare refers to the state of an animal, we should be able to use measurements of that state to indicate welfare and Bateson (1997) has argued that the animal should be given the benefit of the doubt as regards the existence of anxiety, suffering and pain. Animal welfare science is a scientific discipline, which has developed rapidly in recent years. Much of the research has been carried out on domestic animals but the basic methodology is the same for all species including wild animals (Broom 1999). Stress is the sum of the biological reactions to any adverse stimulus, internal or external, that tend to disturb the homeostasis of an organism. The need to minimise stress should be self-evident simply because of the problems related to it. Stress alters the “normal” physiology of an animal and can induce a pre-pathological state. In a prolonged situation of stress, the pre-pathological state provides an opportunity for the development of pathologic change. Stress is usually caused by excessive exertion or fear during translocation. The many unfamiliar events that occur during this procedure lead to both psychological stress as well as the physical stress of muscular exertion. This exertion may result in damage that can lead to development of a pathological state. Capture myopathy is an important stress-induced condition, most frequently encountered in wild animals. It frequently occurs following prolonged and intense chases or manipulations. The proximate cause for capture myopathy is probably a combination of fear and anxiety accompanied by muscle exertion. Fear is the single most important factor in capture myopathy. There are four categories of capture myopathy according to the way the condition presents itself. Peracute Capture Myopathy (death may occur suddenly or in a matter of minutes), Acute Capture Myopathy (this is a less severe form of the above with the animal lingering before death; death occurs in 24-48 hours), Sub-acute Capture Myopathy (again a less severe form of the above; death takes a few days) and Chronic Capture Myopathy (these animals live for several days or months but their ability to survive may be compromised). Hare Coursing The link between enclosed hare coursing and the factors responsible for capture myopathy is indisputable. In Great Britain and Ireland, the most common sufferers of capture myopathy in the wild mammal fraternity are deer and hares. Rabbits, which are also members of the Leporidae family, may die suddenly when stressed or succumb to life threatening illness such as stress enteritis. Both hares and rabbits have been known to die of cardiac arrest brought on by stress or fear of being caught and it is likely that hare coursing or other hunting with dogs will cause very poor welfare in hares.
In Ireland, where enclosed hare coursing takes place, these outcomes are very apparent. The trauma has been documented by the coursers themselves. In “Some Thoughts on The Feeding and Management of Hares - The Abbeyfeale Experience”, the Irish Coursing Club’s veterinary surgeon, JJ O’Sullivan, states that: “It is impossible to completely avoid stress in hares once you manhandle them, and take them out of their natural environment. Stress can come in many shapes and forms and as long as you have the hare in captivity, he is prone to it - resulting in his disability and even death at times. I believe a lot of damage can be done to hares by rough handling and netting.” Mr O’Sullivan goes on to elaborate on causes of stress of netted hares as follows: “Stress can start from the very minute you get him out of his form until you land him in the net, followed by rough handling, boxing and transporting.” Jerry Desmond, Irish Coursing Club Chief Executive, is on record as saying “When hares get injured, they find it very difficult to recuperate from any form of injury.” Dr Donald M Broom, Professor of Animal Welfare, University of Cambridge states that: “When a mammal like a hare is chased by a predator like a dog, it will show physiological changes associated with extreme fear. These include greatly elevated heart rate and high levels of emergency adrenal hormone production as well as other changes in hormone levels and enzymes. “Extreme responses like those shown when chased by a predator can result in reduced life expectancy due to the immediate dangers of injury during very vigorous activity and greater risk of cardiovascular or other breakdown as a consequence of the response. We must conclude that, whether or not the hare is caught, its welfare is very poor during the chase and for periods afterwards which will be prolonged in some cases.” In November 2002, researchers from Queen’s University Belfast carried out an 11-week study of eight Irish hares (Lepus timidus hibernicus) that had been netted, kept in captivity and used for enclosed coursing. After coursing, radio-collars were attached and the animals were radio-tracked after release. All hares radio-collared were judged to be good condition by the attending veterinary surgeon. During the study period two hares died, both within 11 days. Although one had been eaten, the cause of death of both specimens was not determined. Given that both hares were adults in good condition, the timescale and circumstances of the deaths are consistent with sub-acute or chronic capture myopathy. Conclusion It is widely acknowledged that Irish hare numbers are low and that they have become locally extinct in some areas. There is no evidence that hare coursing makes any positive contribution to Irish hares or their numbers. However, it continues to target those areas where the remaining vulnerable populations still exist. On balance, any activity that may result in capture myopathy, such as hare coursing, must be regarded as a threat to the species. About the author: Mike Rendle has been an active environmentalist for over twenty years. He has a special interest in Ireland’s endangered mammals. An enthusiastic bat worker, Mike identified the newest mammal to be found in Ireland, the Nathusius’ pipistrelle. He is currently co-ordinating an initiative helping to conserve one of our oldest mammals, the Irish hare. A longer version of this report (which includes references) can be found at: www.mikerendle.co.uk/pubs. For more information about hares, visit “The Irish Hare” website at www.irishhare.org More Information: Coursing Cruelty
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