Coping with stress: a survey of Murdoch University veterinary students

Students in veterinary schools can experience stress in balancing the different demands on them-academic, interpersonal, intrapersonal, and professional or work related-as well as managing potential conflict between animal and human interests. Practicing veterinarians report many similar stressors and reactions. Stressful stimuli produce stress reactions that can be inimical to physical and psychological well-being, and students' performance in veterinary programs can be adversely affected if they do not have coping resources. While there has been some research into stress among university students in general, and among medical students in particular, there is little on the experience of veterinary students. This article describes a study by the School of Psychology, commissioned by the Department of Veterinary Clinical Sciences, at Murdoch University in Western Australia. It was designed to investigate the levels and causes of stress among, and the frequency and type of coping strategies used by, fourth- and fifth-year students. Results indicate that the students in this cohort faced frequent stressors and felt at least moderately stressed but did not routinely and systematically use a range of coping strategies. Academic stressors and perceived responsibilities attached to moving into practical or professional areas figured strongly and were associated with higher levels of stress in the students, in particular physical sequelae. Though the numbers were small, it is of concern that some students were using measures that were potentially harmful. Some recommendations are made here about measures that veterinary programs may be able to incorporate to address stress in their students. Information is included on current strategies within the curriculum to manage potential stressful situations as part of students' professional development.     

Coping with blindness: a survey of 50 blind dogs

A telephone survey of 50 owners of blind dogs was made in order to assess how well visually deprived dogs can cope within their environment. Ten of the 50 dogs surveyed died or were euthanased as a direct result of their blindness or ocular disease. Three owners were unable to come to terms with their pet's visual loss. Two dogs died as a result of accidents directly associated with blindness and five dogs were euthanased due to pain caused by glaucoma. Twenty-seven owners reported permanent behaviour or temperament changes in their pets. Behavioural changes included a more cautious approach to the environment and closer contact with the owner. Owners were aware of an obvious compensatory reliance on the senses of hearing and smell. Permanent temperament changes were reported in only two dogs both of whom became more aggressive. Only six of the surveyed dogs were unable or unwilling to find their way around in familiar surroundings. The most consistent measures undertaken by owners to ensure the dogs' safety was to prevent access to roads and to ensure that there was minimal movement of furniture within the home. Six dogs lost interest in exercise after the onset of blindness but a further six were still allowed to roam at large. Of the 32 owners who accompanied their dogs eight reported that restraint on a lead was unnecessary. Twenty-eight owners had encountered people who had suggested it was unkind to keep a blind dog.     

通过添加矿物质来发送与应激相关的挑战

随着生猪生产集约化程度的不断加深,养猪行业对猪生产性能的期望值越来越高。集约化生产方式也带来了许多应激问题,主要表现在打斗、咬尾、自相残杀、运输过程中的高死亡率和猝死综合征以及肉质较差。除了采用管理因素来预防或控制不良影响外,矿物质(尤其是镁)或微量元素的补充在缓解应激上也能发挥着重大作用。     

高山美利奴羊羔羊管理应对策略

高山美利奴羊对干旱寒冷气候条件有独特的适应性,是在地处高寒牧区的甘肃省肃南县皇城镇境内的甘肃省绵羊繁育技术推广站培育而成,是甘肃省第一个国家级细毛羊培育品种。高山美利奴羊各个阶段的饲养管理,对其一生发展都有及其重要的意义,直接影响羊的生产性能和繁殖性能,尤其是高山美利奴羊羔羊管理阶段显得更为重要,如果在此阶段饲养管理不善,各个环节不到位,一定会给广大农牧户和养殖企业造成较大的经济损失。笔者通过多年的饲养管理,总结出了高山美利奴羊羔羊饲养管理中的一此经验和作法,并取得了一定的成绩,供广大牧户和养殖企业参考。     

锌抗热应激效应的研究

养殖业集约化、规模化发展的同时,热应激现象变得越来越严重,在一定程度上制约了养殖业的发展,迫切需要有效措施来缓解动物的热应激。生产中遇到的热应激常通过改进管理措施加以调控。如加大通风强度、降低温度、减少饲养密度等。但以色列西伯莱大学Cahaner报道,鸡的热应激和冷应激不会通过管理措施而完全消除。     

Stress Reactivity and Coping in Horse Adaptation to Environment

“Coping” or “coping strategy”, defined as the behavioral and physiological efforts of animal to master the situation, is more and more in interest of researchers dealing with applied animal behavior and welfare. Knowledge about “coping styles” may be helpful in understanding individual adaptive capacity to stressful events. At least two types of animal coping strategy (or coping style) can be involved: (1) active copers (proactive) and (2) passive copers (reactive). The individual differences in stress response to threatening situations have been found in horses, and these animals can show specific coping strategies such as other species. This article reviews the set of behavioral, psychoneuroendocrine, and psychoneuroimmune mechanisms involved in animal adaptation to environmental challenges and discusses the relationship between behavioral and physiological factors involved in stress response of the horse. Exploring coping strategies in horses and in any captive animal can be successful when a multidimensional approach including behavioral, neural, hormonal, and hematological measures is considered. Knowledge on stress coping styles can provide valuable information to predict the behavior of individuals during response to specific challenging situations. Moreover, assessing individual differences in adaptation strategies can be useful in horse selection to different exploitation tasks and reproduction.     

A bovine stress syndrome associated with exercise-induced hyperthermia

OBJECTIVE: To investigate an exercise-induced bovine stress syndrome under field and controlled experimental conditions. DESIGN AND PROCEDURE: In the field study, cattle affected with the stress syndrome were observed while they were grazing and during normal mustering using horses. This study served to define the clinical nature of the syndrome. The experimental study utilised three affected and five normal unaffected cattle. These animals were compared on the basis of their response to a defined exercise program, which consisted of walking 3.6 km in 2 h. Blood samples and measurements of respiratory rate, ambient temperature and rectal temperature were taken immediately before exercise, and at 0.5, 1.0, 1.5 and 2.0 h during the exercise and 24 h later. Clinical and blood constituent data were subjected to standard analysis of variance and repeated measures analysis. RESULTS: In the field study, affected cattle were observed to show abnormally anxious and hyperactive behaviour. This behaviour was exhibited by affected cattle during the experimental exercise program where it was shown to be accompanied by hyperthermia and hyperventilation. The experimental study showed that affected cattle developed metabolic acidosis and became hyperglycaemic. Their plasma creatine kinase activity remained markedly increased at 24 h after exercise but other clinical and blood constituent variables had returned to normal values. CONCLUSION: The clinical and biochemical changes detected in affected cattle were consistent with exercise-induced malignant hyperthermia.     

Oxidative stress in farmed minks with self-biting behavior

Self-biting behavior (SBB) is a serious behavioral disorder in farmed minks, but little is known about the biological basis of this disorder. The present study examined for the first time the hepatic and cerebral oxidative stress biomarker levels in SBB minks and compared them with those in normal ones to study the association of oxidative stress and SBB in minks. Calcium-activated adenosine triphosphatase (Ca²⁺ATPase) activities were also determined to investigate whether the Ca²⁺ pump in brain is affected. Twenty male SBB minks and 20 male normal minks were chosen in December. The brain and liver of each mink were harvested immediately after slaughter to test oxidative stress biomarkers. All parameters were determined by using a spectrophotometer. Our findings were as follows: SBB minks produced more malondialdehyde with 51% increase in brain (P < 0.01) and 22% increase in liver (P < 0.01) compared with normal minks. Similarly, the hepatic and cerebral protein carbonyls in SBB minks were 18.5% (P < 0.01) and 30% higher (P < 0.001), respectively. Glutathione peroxidase activities in brain and catalase activities in both tissues of SBB minks were markedly lower than those of normal group (P < 0.01). However, SBB minks had higher total superoxide dismutase (SOD), Cu/Zn-SOD, and Mn-SOD activities in both tissues (P < 0.05 or P < 0.01). Significant depletion of glutathione and vitamin E levels were observed in SBB minks (P < 0.01 or P <0 .05). Calcium-activated adenosine triphosphatase activities in the brain of SBB minks were inhibited (P < 0.01). Our results supported the oxidative stress hypothesis in minks with SBB.     

鸡应激反应的调整对策

一 加强饲养管理 管理措施得当。要根据鸡的周龄、体重等参数,及时调整饲料配方,配足各种营养成分。适时逐步更换饲料。要采取合理的措施,控制好鸡舍内的温度、湿度、光照,减少噪声对鸡群的影响,搞好养殖场韵环境调控,避免各种宠物和小动物进入鸡舍,窗户上最好安置防护网,这样能防止飞鸟进入鸡舍骚扰鸡群。加强饲料和垫料管理,防止霉菌污染,发现霉菌滋生时,要及时进行清除。加强鸡舍内的通风管理,及时排除有害气体,要求舍内无死角、无贼风,冬春季要在鸡舍内设置挡板,以免鸡群直接吹风。搞好鸡舍卫生调控,定时清理粪便,带鸡消毒必须选用无刺激性的消毒剂。     

Association between heat stress and oxidative stress in poultry;mitochondrial dysfunction and dietary interventions with phytochemicals

Heat as a stressor of poultry has been studied extensively for many decades; it affects poultry production on a worldwide basis and has significant impact on well-being and production. More recently, the involvement of heat stress in inducing oxidative stress has received much interest. Oxidative stress is defined as the presence of reactive species in excess of the available antioxidant capacity of animal cells. Reactive species can modify several biologically cellular macromolecules and can interfere with cell signaling pathways. Furthermore, during the last decade, there has been an ever-increasing interest in the use of a wide array of natural feed-delivered phytochemicals that have potential antioxidant properties for poultry. In light of this, the current review aims to(1) summarize the mechanisms through which heat stress triggers excessive superoxide radical production in the mitochondrion and progresses into oxidative stress,(2) illustrate that this pathophysiology is dependent on the intensity and duration of heat stress,(3) present different nutritional strategies for mitigation of mitochondrial dysfunction, with particular focus on antioxidant phytochemicals.Oxidative stress that occurs with heat exposure can be manifest in all parts of the body; however, mitochondrial dysfunction underlies oxidative stress. In the initial phase of acute heat stress, mitochondrial substrate oxidation and electron transport chain activity are increased resulting in excessive superoxide production. During the later stage of acute heat stress, down-regulation of avian uncoupling protein worsens the oxidative stress situation causing mitochondrial dysfunction and tissue damage. Typically, antioxidant enzyme activities are upregulated. Chronic heat stress, however, leads to downsizing of mitochondrial metabolic oxidative capacity, up-regulation of avian uncoupling protein, a clear alteration in the pattern of antioxidant enzyme activities, and depletion of antioxidant reserves.Some phytochemicals, such as various types of flavonoids and related compounds, were shown to be beneficial in chronic heat-stressed poultry, but were less or not effective in non-heat-stressed counterparts. This supports the contention that antioxidant phytochemicals have potential under challenging conditions. Though substantial progress has been made in our understanding of the association between heat stress and oxidative stress, the means by which phytochemicals can alleviate oxidative stress have been sparsely explored.