Laboratory soundscapes: optimising acoustic environments for avian welfare

音乐对我们的情绪有深远的影响，增加了快乐，减少了焦虑。人们普遍认为，音乐对其他动物也有类似的效果，人们经常向圈养的动物播放音乐，以改善它们的福利。然而，我们实际上对音乐对动物的长期影响知之甚少。事实上，音乐可能不是声学丰富的最合适的形式。一个重要的观点是，动物在圈养、科学研究或农场中听到的声音可以提高生活质量。仅在英国，每年就有超过400万只动物被用于科学实验，据估计，全世界还有1亿只。最大化这些动物的福利是许多政策制定机构的重要关注点，包括英国政府和欧洲议会。其中许多政策制定者的中心目标是在科学数据的基础上制定最佳实践，以改善用于科学程序的动物的健康和福祉。我们可以为圈养动物创造更好的环境的一种方法是丰富它们围栏内的声环境(音景)。然而，没有关于动物更喜欢听到的声音类型的数据。这显然是告诉我们丰富的音景听起来是什么样子的第一步。听首选的音景可以减轻压力，限制与圈养有关的人为噪音(例如机械)的影响，并减少焦虑。这可能会导致生理福利指标的整体增加，并意味着动物更健康、更快乐。我们打算用几个创新的实验来检验这一假设。我们将使用斑马雀来做这件事，斑马雀可以说是世界上研究最广泛的鸣禽。在世界各地的研究实验室里，每年有30万只鸣鸟被用于研究社会行为、认知、神经生物学、生理学、听觉感知和福利，它们占了大部分。然而，尽管是一个重要的模式物种，关于圈养环境如何影响它们的健康和福祉，人们几乎一无所知。首先，我们将通过让斑马雀在一系列人造、自然和音乐般的声音中进行选择，来发现它们更喜欢听什么声音。一旦我们有了这些信息，我们将用它来构建两个代表丰富的实验性声音场景，一个基于自然声音，另一个基于音乐般的刺激。我们可以将生活在这些环境中的鸟类与那些生活在“正常”音景中的鸟类以及通过隔音消除人为声音的鸟类进行比较。然后，我们将在八个月的时间里观察成年鸟类的健康、压力水平和行为，以确定长期暴露在丰富的声音中对福利的影响。在此之后，我们将确定我们的音景对繁殖性能的影响，以及在后代发育期间听到这些声音的影响。在所有鸟类中，我们将专注于测量我们知道的与健康和福祉有关的特征，包括压力水平、焦虑行为、免疫能力、社会凝聚力和氧化分子对细胞的损害。研究的最后部分将调查丰富的声景是否可以增加鸟类参与行为实验的可能性(以了解新的物体或食物来源)。这种类型的实验通常需要训练鸟类，在大多数研究中，10%-20%的动物不参与这项任务。这可能是由于测试过程中的高压力水平，而音景可能能够改善这一点。总体而言，我们的工作旨在提高实验室环境中的鸟类福利，我们相信，这将对其他环境产生影响，如饲养的鸟类。此外，我们将能够对目前的福利协议进行重大改进。我们还建议，这项工作将显著减少行为实验中使用的动物数量。

Music has profound effects on our mood, increasing happiness and decreasing anxiety. It is commonly believed that music has similar effects in other animals, and music is often played to captive animals to improve their welfare. However, we actually know very little about the long-term effects of music on animals. In fact, music may not be the most appropriate form of acoustic enrichment. The idea that the sounds animals hear when in captivity, in scientific studies or on a farm, can enhance quality of life is an important one. Over four million animals are used in scientific experiments each year in the UK alone, with a further 100 million estimated worldwide. Maximising the welfare of these animals is an important focus of many policy-making bodies, including the UK Government and European Parliament. The central aim of many of these policy makers is to develop best practices based on scientific data to improve the health and wellbeing of animals used in scientific procedures. One way that we could create better environments for captive animals is to enrich the acoustic surroundings (soundscapes) within their enclosures. However, there are no data on the types of sounds that animals would prefer to hear. This is the obvious first step in informing our idea of what an enriched soundscape sounds like. Listening to preferred soundscapes could reduce stress, limit the impact of anthropogenic noises associated with captivity (e.g. machinery) and reduce anxiety. This could lead to an overall increase in physiological welfare indicators and mean healthier and happier animals. We intend to test this hypothesis using several innovative experiments. We will do this using the zebra finch, which are arguably the most extensively studied songbirds in the world. They account for the majority of the 300,000 songbirds used annually for studies on social behaviour, cognition, neurobiology, physiology, auditory perception, and welfare in research laboratories worldwide. Yet despite being an important model species, almost nothing is known about how acoustic environments in captivity impact their health and wellbeing. Firstly we will discover what sounds zebra finches prefer to hear by giving them the choice between a range of man-made, natural and music-like sounds. Once we have this information we will use it to construct two experimental soundscapes that represent enrichment, one based on natural sounds the other on music-like stimuli. We can compare birds living in these environments to those in 'normal' soundscapes and a group that has anthropogenic sounds removed by soundproofing. We will then look at adult bird health, stress levels and behaviour over an eight month period to establish how long-term exposure to enriched sounds impacts on welfare. After this we will determine the effects of our soundscapes on breeding performance and the effects of hearing these sounds during development of the offspring. In all birds we will focus on measuring traits that we know relate to health and wellbeing, including stress levels, anxiety behaviour, immunocompetence, social cohesion and damage to cells by oxidative molecules. The final part of the study will investigate whether enriched soundscapes can increase the likelihood of birds to participate in behavioural experiments (to learn about a new object or food source). This type of experiment often requires training the birds and in most studies 10-20% of animals do not engage with the task. This may be due to high stress levels during tests, which soundscapes may be able to ameliorate. Overall our work aims to enhance avian welfare in a laboratory setting, and we are confident that it will have repercussions beyond this into other environments, such as farmed birds. In addition we will be able to produce a significant refinement of current welfare protocols. We also suggest that the work will lead to significant reductions in the numbers of animals used in behavioural experiments.