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Ji A.,Marquette University | Johnson M.T.,Marquette University | Walsh E.J.,Boys Town National Research Hospital | McGee J.,Boys Town National Research Hospital | Armstrong D.L.,Omahas Henry Doorly Zoo
Journal of the Acoustical Society of America | Year: 2013

This paper investigates the extent of tiger (Panthera tigris) vocal individuality through both qualitative and quantitative approaches using long distance roars from six individual tigers at Omaha's Henry Doorly Zoo in Omaha, NE. The framework for comparison across individuals includes statistical and discriminant function analysis across whole vocalization measures and statistical pattern classification using a hidden Markov model (HMM) with frame-based spectral features comprised of Greenwood frequency cepstral coefficients. Individual discrimination accuracy is evaluated as a function of spectral model complexity, represented by the number of mixtures in the underlying Gaussian mixture model (GMM), and temporal model complexity, represented by the number of sequential states in the HMM. Results indicate that the temporal pattern of the vocalization is the most significant factor in accurate discrimination. Overall baseline discrimination accuracy for this data set is about 70% using high level features without complex spectral or temporal models. Accuracy increases to about 80% when more complex spectral models (multiple mixture GMMs) are incorporated, and increases to a final accuracy of 90% when more detailed temporal models (10-state HMMs) are used. Classification accuracy is stable across a relatively wide range of configurations in terms of spectral and temporal model resolution. © 2013 Acoustical Society of America.

Morris C.L.,Omahas Henry Doorly Zoo | Grandin T.,Colorado State University | Irlbeck N.A.,Colorado State University
Journal of Animal Science | Year: 2011

Animal scientists have an extraordinary burden to promote the health and well-being of all animals in their care. Promoting species- or breedappropriate behaviors through proper training and enrichment, regardless of animal housing, should be a paramount concern for all animal scientists working with exotic animals, laboratory animals, shelter animals, or privately owned pet animals. Developing ideal training and enrichment programs for any species begins with understanding basic behavior patterns and emotional systems of animals. The basic emotional systems in mammals have been extensively mapped; however, most of these studies are in the neuroscience literature and seldom read by animal science professionals. The emotional circuits for fear have been well documented through studies demonstrating that lesions to the amygdala will block both conditioned and unconditioned fear behaviors. Additionally, other core emotional systems including seeking (i.e., approaching a novel stimulus), rage, panic (e.g., separation stress), play, lust (i.e., sex drive), and care (e.g., mother-young nurturing behavior) have been identified. More recent neuroscience research has discovered the subcortical brain regions that drive different types of seeking behaviors. Research to increase the understanding of the emotional systems that drive both abnormal and normal animal behaviors could greatly improve animal welfare by making it possible to provide more effective environmental enrichment programs. Enrichment devices and methods could be specifically designed to enable the expression of highly motivated behaviors that are driven by emotional circuits in the brain. The objective of this paper is to increase awareness of animal scientists to the field of neuroscience studying animal emotions and the application of that science to improve the welfare of captive exotic animals, laboratory animals, and pets with environmental enrichment. © 2011 American Society of Animal Science. All rights reserved.

Titze I.R.,University of Iowa | Titze I.R.,University of Utah | Fitch W.T.,University of Vienna | Hunter E.J.,University of Utah | And 5 more authors.
Journal of Experimental Biology | Year: 2010

Despite the functional importance of loud, low-pitched vocalizations in big cats of the genus Panthera, little is known about the physics and physiology of the mechanisms producing such calls. We investigated laryngeal sound production in the laboratory using an excised-larynx setup combined with sound-level measurements and pressure-flow instrumentation. The larynges of five tigers (three Siberian or Amur, one generic non-pedigreed tiger with Bengal ancestry and one Sumatran), which had died of natural causes, were provided by Omaha's Henry Doorly Zoo over a five-year period. Anatomical investigation indicated the presence of both a rigid cartilaginous plate in the arytenoid portion of the glottis, and a vocal fold fused with a ventricular fold. Both of these features have been confusingly termed 'vocal pads' in the previous literature. We successfully induced phonation in all of these larynges. Our results showed that aerodynamic power in the glottis was of the order of 1.0?W for all specimens, acoustic power radiated (without a vocal tract) was of the order of 0.1?mW, and fundamental frequency ranged between 20 and 100?Hz when a lung pressure in the range of 0-2.0?kPa was applied. The mean glottal airflow increased to the order of 1.0?l?s-1 per 1.0?kPa of pressure, which is predictable from scaling human and canine larynges by glottal length and vibrational amplitude. Phonation threshold pressure was remarkably low, on the order of 0.3?kPa, which is lower than for human and canine larynges phonated without a vocal tract. Our results indicate that a vocal fold length approximately three times greater than that of humans is predictive of the low fundamental frequency, and the extraordinarily flat and broad medial surface of the vocal folds is predictive of the low phonation threshold pressure. © 2010 Published by The Company of Biologists Ltd.

Orozco-Terwengel P.,University of Cardiff | Andreone F.,Museo Regionale di Science Naturali | Louis Jr. E.,Omahas Henry Doorly Zoo | Vences M.,TU Braunschweig
Molecular Ecology | Year: 2013

Madagascar is a biodiversity hotspot with a unique fauna and flora largely endemic at the species level and highly threatened by habitat destruction. The processes underlying population-level differentiation in Madagascar's biota are poorly understood and have been proposed to be related to Pleistocene climatic cycles, yet the levels of genetic divergence observed are often suggestive of ancient events. We combined molecular markers of different variability to assess the phylogeography of Madagascar's emblematic tomato frogs (Dyscophus guineti and D. antongilii) and interpret the observed pattern as resulting from ancient and recent processes. Our results suggest that the initial divergence between these taxa is probably old as reflected by protein-coding nuclear genes and by a strong mitochondrial differentiation of the southernmost population. Dramatic changes in their demography appear to have been triggered by the end of the last glacial period and possibly by the short return of glacial conditions known as the 8K event. This dramatic change resulted in an approximately 50-fold reduction of the effective population size in various populations of both species. We hypothesize these species' current mitochondrial DNA diversity distribution reflects a swamping of the mitochondrial genetic diversity of D. guineti by that of D. antongilii previous to the populations' bottlenecks during the Holocene, and probably as a consequence of D. antongilii demographic expansion approximately 1 million years ago. Our data support the continued recognition of D. antongilii and D. guineti as separate species and flag D. guineti as the more vulnerable species to past and probably also future environmental changes. © 2013 John Wiley & Sons Ltd.

Koutsos E.A.,Mazuri Exotic Animal Nutrition PMI Nutrition Intl LLC | Armstrong D.,Omahas Henry Doorly Zoo | Ball R.,Busch Gardens | Dikeman C.,Omahas Henry Doorly Zoo | And 5 more authors.
Zoo Biology | Year: 2011

In response to new recommendations for feeding giraffe in zoos, giraffe (n = 6) were transitioned from a typical hoofstock diet to diets containing reduced starch, protein, Ca and P and added n3 fatty acids. This diet was fed as a 50:50 mix with alfalfa and grass hay. Over the next 4 years, serum Ca, P, and fatty acids were measured every 6 months (summer and winter). Serum Ca was not affected by season (P = 0.67) or by diet (P = 0.12). Serum P was not affected season (P = 0.14), but was reduced by diet (P<0.01), and serum Ca:P was also increased by diet (P<0.01). The ratio of serum Ca:P tended to be affected by season (P = 0.07), in which animals tended to have greater Ca:P during the summer vs. the winter. The diet transition resulted in reduced serum saturated fatty acids (including lauric, myristic, palmitic, arachidic, and behenic acids), and increases in n6 fatty acids (including linolenic and arachidonic acids) and n3 fatty acids (docosahexaenoic acid) (P<0.05 for each). Overall, this diet transition resulted in blood nutrient profiles that more closely match that of values found in free-ranging giraffe. © 2010 Wiley Periodicals, Inc.

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