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Author Ganswindt, A.; Palme, R.; Heistermann, M.; Borragan, S.; Hodges, J.K. openurl 
  Title Non-invasive assessment of adrenocortical function in the male African elephant (Loxodonta africana) and its relation to musth Type Journal Article
  Year 2003 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume 134 Issue 2 Pages 156-166  
  Keywords Adrenal Cortex/*metabolism/secretion; Adrenal Cortex Function Tests/methods/*veterinary; Adrenocorticotropic Hormone/physiology; Animals; Carbon Isotopes/diagnostic use; Chromatography, High Pressure Liquid/veterinary; Elephants/*metabolism/urine; Feces/*chemistry; Glucocorticoids/analysis/urine; Hydrocortisone/*analysis/diagnostic use/urine; Immunoenzyme Techniques/methods/veterinary; Male; Reproduction/physiology; Sexual Behavior, Animal/physiology; Stress, Psychological/diagnosis/*physiopathology; Testosterone/*analysis/diagnostic use/urine  
  Abstract Adult male elephants periodically show the phenomenon of musth, a condition associated with increased aggressiveness, restlessness, significant weight reduction and markedly elevated androgen levels. It has been suggested that musth-related behaviours are costly and that therefore musth may represent a form of physiological stress. In order to provide data on this largely unanswered question, the first aim of this study was to evaluate different assays for non-invasive assessment of adrenocortical function in the male African elephant by (i) characterizing the metabolism and excretion of [3H]cortisol (3H-C) and [14C]testosterone (14C-T) and (ii) using this information to evaluate the specificity of four antibodies for determination of excreted cortisol metabolites, particularly with respect to possible cross-reactions with androgen metabolites, and to assess their biological validity using an ACTH challenge test. Based on the methodology established, the second objective was to provide data on fecal cortisol metabolite concentrations in bulls during the musth and non-musth condition. 3H-C (1 mCi) and 14C-T (100 microCi) were injected simultaneously into a 16 year old male and all urine and feces collected for 30 and 86 h, respectively. The majority (82%) of cortisol metabolites was excreted into the urine, whereas testosterone metabolites were mainly (57%) excreted into the feces. Almost all radioactive metabolites recovered from urine were conjugated (86% 3H-C and 97% 14C-T). In contrast, 86% and >99% of the 3H-C and 14C-T metabolites recovered from feces consisted of unconjugated forms. HPLC separations indicated the presence of various metabolites of cortisol in both urine and feces, with cortisol being abundant in hydrolysed urine, but virtually absent in feces. Although all antibodies measured substantial amounts of immunoreactivity after HPLC separation of peak radioactive samples and detected an increase in glucocorticoid output following the ACTH challenge, only two (in feces against 3alpha,11-oxo-cortisol metabolites, measured by an 11-oxo-etiocholanolone-EIA and in urine against cortisol, measured by a cortisol-EIA) did not show substantial cross-reactivity with excreted 14C-T metabolites and could provide an acceptable degree of specificity for reliable assessment of glucocorticoid output from urine and feces. Based on these findings, concentrations of immunoreactive 3alpha,11-oxo-cortisol metabolites were determined in weekly fecal samples collected from four adult bulls over periods of 11-20 months to examine whether musth is associated with increased adrenal activity. Results showed that in each male levels of these cortisol metabolites were not elevated during periods of musth, suggesting that in the African elephant musth is generally not associated with marked elevations in glucocorticoid output. Given the complex nature of musth and the variety of factors that are likely to influence its manifestation, it is clear, however, that further studies, particularly on free-ranging animals, are needed before a possible relationship between musth and adrenal function can be resolved. This study also clearly illustrates the potential problems associated with cross-reacting metabolites of gonadal steroids in EIAs measuring glucocorticoid metabolites. This has to be taken into account when selecting assays and interpreting results of glucocorticoid metabolite analysis, not only for studies in the elephant but also in other species.  
  Address German Primate Centre, Department of Reproductive Biology, Kellnerweg 4, 37077 Gottingen, Germany. ganswindt@www.dpz.gdwg.de  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0016-6480 ISBN Medium  
  Area Expedition (up) Conference  
  Notes PMID:14511986 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4085  
Permanent link to this record
 

 
Author van der Kolk, J.H.; Nachreiner, R.F.; Schott, H.C.; Refsal, K.R.; Zanella, A.J. openurl 
  Title Salivary and plasma concentration of cortisol in normal horses and horses with Cushing's disease Type Journal Article
  Year 2001 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 33 Issue 2 Pages 211-213  
  Keywords Adrenal Cortex Function Tests/standards/veterinary; Animals; Cushing Syndrome/diagnosis/metabolism/*veterinary; Female; Horse Diseases/blood/*diagnosis/metabolism; Horses/blood/*metabolism; Hydrocortisone/blood/*metabolism; Male; Predictive Value of Tests; Reference Values; Saliva/*metabolism  
  Abstract  
  Address Department of Large Animal Medicine and Nutrition, Veterinary Faculty, Utrecht University, The Netherlands  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition (up) Conference  
  Notes PMID:11266074 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4281  
Permanent link to this record
 

 
Author Aerts, J.-M.; Gebruers, F.; Van Camp, E.; Berckmans, D. doi  openurl
  Title Controlling horse heart rate as a basis for training improvement Type Journal Article
  Year 2008 Publication Computers and Electronics in Agriculture Abbreviated Journal  
  Volume 64 Issue 1 Pages 78-84  
  Keywords Heart rate; Horse; Model predictive control; Transfer function model  
  Abstract Equine training methods, and consequently, performance times have improved little since the last decades. With advances in measuring signals on-line by means of several new technologies and analytical procedures, and processing these signals immediately with strong and compact processors, it may be possible to develop new training methods. In this research, the objective was to explore the possibilities of using modern model-based algorithms to control the heart rate of horses (bpm) on-line by means of the control input running speed (km/h). Forty-five experiments with five horses and four riders were carried out to generate measurements of physiological status during running. The dynamical characteristics of each horse were quantified using linear discrete transfer function models. The dynamic response of heart rate to step changes in running speed were accurately described. In 90% of the cases, a first-order model gave the best fit. For 69% of the models, the r2 was higher than 0.90 and for 34% of the models, the r2 was even higher than 0.95. In a next step, the model-based algorithm was evaluated by controlling cardiac responses of two horses (horses 2 and 4) to a pre-defined trajectory. The model parameters were kept constant. On average, the error between the defined target trajectory in heart rate and the actual controlled heart rate ranged between 0.2 and 1.4 bpm for the whole target heart rate trajectory. During the steady-state part of the trajectory the average error was maximum 1.1 bpm. In the transient from one steady-state heart rate to another level, the error could increase on average up to 5 bpm. In the future, the combination of on-line measured bioresponses with real-time analysis can be used for adjusting the work load of the horse, during training, directly to the immediate needs of horse (welfare) and trainer (performance).  
  Address Division Measure, Model and Manage Bioresponses (M3-BIORES), Katholieke Universiteit Leuven, Kasteelpark Arenberg 30, B-3001 Leuven, Belgium  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition (up) Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4555  
Permanent link to this record
 

 
Author Rogers, L.J. url  doi
openurl 
  Title Evolution of hemispheric specialization: advantages and disadvantages Type Journal Article
  Year 2000 Publication Brain and Language Abbreviated Journal Brain Lang  
  Volume 73 Issue 2 Pages 236-253  
  Keywords Aggression/psychology; Animals; Behavior, Animal/physiology; Brain/*physiology; Chickens/physiology; *Evolution; Feeding Behavior/physiology; Functional Laterality/*physiology; Visual Fields/physiology; Visual Perception/physiology  
  Abstract Lateralization of the brain appeared early in evolution and many of its features appear to have been retained, possibly even in humans. We now have a considerable amount of information on the different forms of lateralization in a number of species, and the commonalities of these are discussed, but there has been relatively little investigation of the advantages of being lateralized. This article reports new findings on the differences between lateralized and nonlateralized chicks. The lateralized chicks were exposed to light for 24 h on day 19 of incubation, a treatment known to lead to lateralization of a number of visually guided responses, and the nonlateralized chicks were incubated in the dark. When they were feeding, the lateralized chicks were found to detect a stimulus resembling a raptor with shorter latency than nonlateralized chicks. This difference was not a nonspecific effect caused by the light-exposed chicks being more distressed by the stimulus. Instead, it appears to be a genuine advantage conferred by having a lateralized brain. It is suggested that having a lateralized brain allows dual attention to the tasks of feeding (right eye and left hemisphere) and vigilance for predators (left eye and right hemisphere). Nonlateralized chicks appear to perform these dual tasks less efficiently than lateralized ones. Reference is made to other species in discussing these results.  
  Address Division of Zoology, University of New England, Armidale, New South Wales, Australia. lrogers@metz.une.edu.au  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0093-934X ISBN Medium  
  Area Expedition (up) Conference  
  Notes PMID:10856176 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4621  
Permanent link to this record
 

 
Author Rizhova, L.Y.; Kokorina, E.P. url  doi
openurl 
  Title Behavioural asymmetry is involved in regulation of autonomic processes: Left side presentation of food improves reproduction and lactation in cows Type Journal Article
  Year 2005 Publication Behavioural Brain Research Abbreviated Journal Behav. Brain. Res.  
  Volume 161 Issue 1 Pages 75-81  
  Keywords Behavioural asymmetry; Somatic functions; Reproduction; Lactation  
  Abstract It is known that the right and left brain hemispheres differ in their ability to regulate autonomic processes in the organism. Direct unilateral stimulation of the brain provokes side-dependent endocrine, immune and other visceral reactions. Since brain hemispheres are mainly involved in the regulation of muscles and sensory organs on the contra lateral side of the body the activation of behavioural asymmetry stimulates the contra lateral half of the brain. The important theoretical and practical question of whether autonomic processes can be regulated via the behavioural asymmetry route remains unexplored. In this study, we report that the chronic presentation of an emotionally important stimulus--food--from the left side, improves reproductive performance in animals in a broad range of feeding conditions. The unilateral presentation of food can also influence lactation, but in this case the side-dependent effects are different under varying feeding conditions. This finding opens a simple practical approach to influence basic somatic functions in the organism.  
  Address  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0166-4328 ISBN Medium  
  Area Expedition (up) Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5348  
Permanent link to this record
 

 
Author Krishnan, A.; Gandour, J.T.; Ananthakrishnan, S.; Bidelman, G.M.; Smalt, C.J. url  doi
openurl 
  Title Functional ear (a)symmetry in brainstem neural activity relevant to encoding of voice pitch: A precursor for hemispheric specialization? Type Journal Article
  Year Publication Brain and Language Abbreviated Journal  
  Volume In Press, Corrected Proof Issue Pages  
  Keywords Auditory; Human; Brainstem; Pitch; Language; Mandarin Chinese; Fundamental frequency-following response (FFR); Functional ear asymmetry; Experience-dependent plasticity; Subcortical  
  Abstract Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and right ear of 15 native speakers of Mandarin Chinese using two synthetic speech stimuli that differ in linguistic status of tone. One represented a native lexical tone (Tone 2: T2); the other, T2', a nonnative variant in which the pitch contour was a mirror image of T2 with the same starting and ending frequencies. Two 40-ms portions of f0 contours were selected in order to compare two regions (R1, early; R2 late) differing in pitch acceleration rate and perceptual saliency. In R2, linguistic status effects revealed that T2 exhibited a larger degree of FFR rightward ear asymmetry as reflected in f0 amplitude relative to T2'. Relative to midline (ear asymmetry = 0), the only ear asymmetry reaching significance was that favoring left ear stimulation elicited by T2'. By left- and right-ear stimulation separately, FFRs elicited by T2 were larger than T2' in the right ear only. Within T2', FFRs elicited by the earlier region were larger than the later in both ears. Within T2, no significant differences in FFRS were observed between regions in either ear. Collectively, these findings support the idea that origins of cortical processing preferences for perceptually-salient portions of pitch are rooted in early, preattentive stages of processing in the brainstem.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0093-934x ISBN Medium  
  Area Expedition (up) Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5391  
Permanent link to this record
 

 
Author Güntürkün, O.; Kesch, S. doi  openurl
  Title Visual lateralization during feeding in pigeons Type Journal Article
  Year 1987 Publication Behavioral Neuroscience Abbreviated Journal Behav. Neurosci.  
  Volume 101 Issue 3 Pages 433-435  
  Keywords use of right vs left eye, amount & accuracy of pecking in food discrimination task, homing pigeons, implications for lateralization of cerebral function  
  Abstract In a quasi-natural feeding situation, adult pigeons had to detect and consume 30 food grains out of about 1,000 pebbles of similar shape, size, and color within 30 s under monocular conditions. With the right eye seeing, the animals achieved a significantly higher discrimination accuracy and, consequently, a significantly higher proportion of grains grasped than with the left eye seeing. This result supports previous demonstrations of a left-hemisphere dominance for visually guided behavior in birds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  
  Address  
  Corporate Author Thesis  
  Publisher US: American Psychological Association Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1939-0084(Electronic);0735-7044(Print) ISBN Medium  
  Area Expedition (up) Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ 1987-30501-001 Serial 5588  
Permanent link to this record
 

 
Author Rogers, L.J. doi  openurl
  Title A Matter of Degree: Strength of Brain Asymmetry and Behaviour Type
  Year 2017 Publication Symmetry Abbreviated Journal Symmetry  
  Volume Issue Pages  
  Keywords functional asymmetry; strength of lateralization; direction of lateralization; advantages; disadvantages; vertebrate species; limb preference; eye bias  
  Abstract Research on a growing number of vertebrate species has shown that the left and right sides of the brain process information in different ways and that lateralized brain function is expressed in both specific and broad aspects of behaviour. This paper reviews the available evidence relating strength of lateralization to behavioural/cognitive performance. It begins by considering the relationship between limb preference and behaviour in humans and primates from the perspectives of direction and strength of lateralization. In birds, eye preference is used as a reflection of brain asymmetry and the strength of this asymmetry is associated with behaviour important for survival (e.g., visual discrimination of food from non-food and performance of two tasks in parallel). The same applies to studies on aquatic species, mainly fish but also tadpoles, in which strength of lateralization has been assessed as eye preferences or turning biases. Overall, the empirical evidence across vertebrate species points to the conclusion that stronger lateralization is advantageous in a wide range of contexts. Brief discussion of interhemispheric communication follows together with discussion of experiments that examined the effects of sectioning pathways connecting the left and right sides of the brain, or of preventing the development of these left-right connections. The conclusion reached is that degree of functional lateralization affects behaviour in quite similar ways across vertebrate species. Although the direction of lateralization is also important, in many situations strength of lateralization matters more. Finally, possible interactions between asymmetry in different sensory modalities is considered.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title Symmetry  
  Series Volume 9 Series Issue 4 Edition  
  ISSN 2073-8994 ISBN Medium  
  Area Expedition (up) Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 6167  
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