A comparative analysis of the acoustic structure of separation calls of Mongolian wild horses (Equus ferus przewalskii) and domestic horses (Equus caballus)

In equines, calls given by foals or mothers when they are seeking contact with each other or by stallions seeking contact with other group members could be classified as affiliative or separation calls when a reunion follows the vocalizations. To investigate how domestication can affect the characteristics of vocalizations produced by equines, separation calls produced by Przewalski's (Przw) horses and Mongolian domestic horses (MDH) living in the same habitat were recorded, spectrally analyzed, and compared. Species-specific acoustic differences were found in the separation vocalizations of mares and foals. In particular, the second and third formants of the calls emitted by Przw mothers were significantly higher in frequency than those emitted by Mongolian domestic mothers, whereas the same acoustical variables were significantly lower in Przw foals than Mongolian domestic foals. Second and third formants have a significant effect on discriminating separation calls emitted by mares and foals from these different equine species. With the exception of the duration of the call, no significant species-specific differences in acoustic parameters were observed in separation calls emitted by stallions. Bioacoustic analysis can discriminate 2 different species that can be affected by their environment, evolution, and social organization.     

Gonadesiklus van die kroonkiewiet Vanellus coronatus op enkele binnelandse lughawens

Gonadal cycle of the crowned plover Vanellus coronatus at two inland airports. The gonadal cycle of 474 crowned plovers Vanellus coronatus collected from two inland airports during 1986/87 was investigated. Judged by the ovarian mass and the diameter of the largest visible follicle, a prominent activity peak occurs in the ovarian cycle of females during early summer. Judged by the mass, volume, histological development stages and diameter jof the seminiferous tubules of the testes, a corresponding but longer activity peak also occurs among males. Although the testes of immature males are generally smaller than those of adults, some individuals are potentially capable of reproduction within their first year of life. Evidently the breeding cycle of the crowned plover is influenced to a greater extent by the relative availability of food than by environmental factors such as day length, temperature or rainfall.     

鸣禽鸟的发声中枢及其神经传导通路的研究

鸣禽鸟的发声中枢及其神经传导通路的研究曾庆华，赵玲，姜立嘉（东北师范大学生物系）鸣禽鸟之所以能发出婉动听的鸣叫，不仅仅是依赖于外围发声器（鸣管）来完成，而是经过多级水平的相关中枢组成的机能系统密切配合统一调节方能完成的。这个机能系统称它为各级发声中枢...     

论学习声乐艺术的几点基本要领

声乐艺术是具有独特的规律和一整套歌唱的实践方法和技巧,要成为一名具备较高演唱水平的歌手,必须认真掌握它的学习方法,从而,逐步形成自己的演唱风格,永保艺术生命。     

母羊3种应激行为下叫声信号的对比分析

为研究母羊在不同应激行为下叫声信号所具有的特征,选择体重相近、年龄在2~3岁的小尾寒羊母羊20只,分别录取其在3种应激行为(产羔、寻羔、饥饿)下的叫声信号。利用LabVIEW软件设计母羊发声信号特征提取与识别系统,对母羊发声信号进行时域分析、频域分析(Yule-Walker法估计功率谱、Welch法估计功率谱、线性坐标功率谱和倒谱分析)和时频域分析,提取发声信号的时间间隔、持续时间、主峰频率、能量集中范围和基音周期等特征参数。结果表明:母羊3种不同类型声音的持续时间以及主峰频率均存在显著差异(P0.05)。母羊在寻羔和饥饿时发声的持续时间是产羔时的1.93和1.82倍,饥饿叫声的主频分别为产羔和寻羔时的34.77和38.81倍,母羊叫声信号Yule-Walker法功率谱在饥饿出现1个峰值,寻羔时出现2个峰值,而产羔时无明显峰值。叫声信号能量在产羔时集中在400~600Hz,寻羔和饥饿时集中在0~900Hz,3种叫声基音周期接近为0.1ms。证明母羊叫声信号在3种应激行为下有明显的不同,因此可以作为评价其健康状况及福利化养殖水平的重要指标之一。     

Opioid dysphoria in three dogs

Objective: To describe the clinical manifestations and response to management of opioid dysphoria in 3 dogs. Case summary: Three dogs being managed for post‐operative pain were evaluated. All 3 dogs had been managed with various opioids including morphine, hydromorphone, and fentanyl following the surgical procedure. The 3 dogs exhibited vocalization that did not respond to interaction and did not change with administration of analgesic and anxiolytic agents. The dogs were treated with naloxone and, within 5 minutes of its administration, ceased vocalizing, and became aware and interactive with their environment. Further pain management consisted of non‐steroidal anti‐inflammatory medications, alpha‐2 (α₂) receptor agonists or the partial μ‐receptor opioid agonist, buprenorphine. New and unique information provided: Vocalization and lack of response to interaction with humans are clinical signs which can be seen in dogs with opioid dysphoria, and generally are not responsive to analgesics or sedation. Reversal with naloxone results in rapid resolution of vocalization and opioid‐induced dysphoria.     

含风机噪声的蛋鸡声音信号去噪方法比较

蛋鸡声音可用来评价蛋鸡本身的福利状况,然而蛋鸡舍中往往存在着低频风机噪声干扰蛋鸡声音信号的时频特征。为了优化含风机噪声的蛋鸡声音信号,以海兰褐蛋鸡为例,利用数字化声音采集平台,采集了不同的蛋鸡叫声和风机噪声。采用LabVIEW软件,分析了蛋鸡声音和风机噪声的时频特征,同时比较了滤波器和小波去噪方法在去除风机噪声方面的应用效果。结果表明,蛋鸡产蛋期间的声音频率范围为400~2 500 Hz,而风机噪声的频率在600 Hz以内。在信噪比为-20~10 dB蛋鸡声音环境中,无限脉冲响应滤波器滤波后的均方根误差要比有限脉冲响应滤波器滤波后的均方根误差小,说明无限脉冲响应滤波器具有更好的滤波效果,与其他小波阈值去噪方法相比,以史坦无偏似然估计为阈值的小波去噪方法在去噪后的均方根误差最小,表明这种方法的去噪效果更好。该研究可为蛋鸡舍中风机噪声环境下的蛋鸡声音识别提供参考。     

基于偏度聚类的哺乳期母猪声音特征提取与分类识别

哺乳期是母猪繁育仔猪的关键时期,哺乳母猪特有的发声是其生理、情绪健康及其对仔猪看护的母性能力的最直接表达。哺乳期间母猪所发声音种类众多,增加了快速定位及准确识别特定声音类型的复杂度,以小梅山母猪的哺乳声、饮水声、采食声及无食咀嚼声等常见声音为研究对象,以功率比作为特征向量,对频域进行更精细的能量计算,提出基于偏度的子带聚类法合并特征不显著的子带,减少特征向量数量,构建支持向量机(SVM)的声音分类识别器,统计各类声音的发声时长;进一步以单个哺乳周期为对象,建立成功哺乳的声音模式。试验结果表明,哺乳声、无食咀嚼声、采食声和饮水声的最大功率比分别位于[0 Hz,1 000 Hz]、[1 000 Hz,1 500 Hz]、[1 500 Hz,2 500 Hz]和[2 500 Hz,8 000 Hz]子带内,以4个子带的功率比为特征的声音判别模型的识别率分别为100%、100%、95.17%、96.61%,与等间隔子带划分及主成分分析法比较,减少了特征向量的数量,且显著提高了识别算法的精度,进一步应用在母猪分娩舍内,实现了对哺乳母猪的母性能力及其健康状况的无应激、实时监测。     

基于改进MFCC的家禽发声特征提取方法

动物的发声包含丰富的信息,能够在一定程度上反馈其自身机体状况及对环境的应激情况,因此发声已成为评价动物福利的一个重要参考指标。为了实现对动物发声信息的自动采集与分析,该研究针对蛋鸡,探索采用不同特征提取算法用于识别蛋鸡叫声。在分析线性预测倒谱参数(LPCC)与梅尔频标倒谱系数法(MFCC)的基础上,结合识别的目标,提出了改进的平均梅尔频标倒谱系数法(AMFCC),并针对三种不同的特征提取算法采用支持向量机分类模型进行了正确识别效率验证,结果表明改进的AMFCC方法比前两种算法正识效率有显著提高。     

蛋鸡发声与机械噪声特征提取及分类识别

规模化蛋鸡舍中不同机械设备运行所产生的噪声会干扰蛋鸡声音提取。为了分析分类识别蛋鸡发声与机械噪声的可行性,该研究以蛋鸡产蛋发声、鸣唱声和规模化蛋鸡舍中通风系统、饲喂系统、清粪系统、集蛋系统单独运行时的噪声为研究对象,运用LabVIEW软件提取了蛋鸡发声和机械噪声的功率谱密度,以子带功率比为特征向量,在数据挖掘平台Weka上应用J48决策树算法构建声音分类识别器。结果表明,蛋鸡产蛋发声和鸣唱声的最大功率比位于频率范围689~1 378 Hz内,通风系统噪声和饲喂系统噪声的最大功率比位于频率范围0~689 Hz内,清粪系统噪声和集蛋系统噪声的最大功率比位于频率范围1 378~2 756 Hz内;该声音分类识别模型的平均识别率为93.4%,其中蛋鸡鸣唱声和产蛋发声的识别率分别为85.9%和92.5%,机械噪声的分类识别率更高,说明基于子带功率比的声音识别方法具有较好的识别效果,该结果为规模化蛋鸡养殖舍复杂声音环境中检测蛋鸡声音提供了参考。