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Author | Bergstrom, C.T.; Lachmann, M. | ||||
Title | Signaling among relatives. III. Talk is cheap | Type | Journal Article | ||
Year | 1998 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
Volume | 95 | Issue | 9 | Pages | 5100-5105 |
Keywords | Animal Communication; Animals; Costs and Cost Analysis; *Evolution; Interpersonal Relations; Models, Biological | ||||
Abstract | The Sir Philip Sidney game has been used by numerous authors to show how signal cost can facilitate honest signaling among relatives. Here, we demonstrate that, in this game, honest cost-free signals are possible as well, under very general conditions. Moreover, these cost-free signals are better for all participants than the previously explored alternatives. Recent empirical evidence suggests that begging is energetically inexpensive for nestling birds; this finding led some researchers to question the applicability of the costly signaling framework to nestling begging. Our results show that cost-free or inexpensive signals, as observed empirically, fall within the framework of signaling theory. | ||||
Address | Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA. carl@charles.stanford.edu | ||||
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 | 0027-8424 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:9560235 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 561 | ||
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Author | Doherty, T.J.; Frazier, D.L. | ||||
Title | Effect of intravenous lidocaine on halothane minimum alveolar concentration in ponies | Type | Journal Article | ||
Year | 1998 | Publication | Equine veterinary journal | Abbreviated Journal | Equine Vet J |
Volume | 30 | Issue | 4 | Pages | 300-303 |
Keywords | Anesthetics/administration & dosage/blood/*pharmacology; Anesthetics, Inhalation/administration & dosage/*analysis; Animals; Consciousness/drug effects; Dose-Response Relationship, Drug; Halothane/administration & dosage/*analysis; Horses/*physiology; Infusions, Intravenous/veterinary; Lidocaine/administration & dosage/blood/*pharmacology; Male | ||||
Abstract | This study investigated the effect of lidocaine i.v. on halothane minimum alveolar concentration (MAC) in ponies. Six ponies were anaesthetised with thiopentone and succinylcholine, intubated and anaesthesia maintained with halothane. Ventilation was controlled and blood pressure maintained within clinically acceptable limits. Following a 2 h equilibration period, baseline halothane MAC was determined. The ponies were then given a loading dose of lidocaine (2.5 or 5 mg/kg bwt) or saline over 5 min, followed by a constant infusion of lidocaine (50 or 100 microg/kg/min, or saline, respectively). The halothane MAC was redetermined after a 60 min infusion of lidocaine or saline. The baseline halothane MAC for the control group was mean +/- s.d. 0.94 +/- 0.03%, and no significant decrease occurred following saline infusion. Lidocaine decreased halothane MAC in a dose-dependent fashion (r = 0.86; P < 0.0003). The results indicate that i.v. lidocaine may have a role in equine anaesthesia. | ||||
Address | Department of Large Animal Clinical Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville 37901-1071, USA | ||||
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 | Conference | |||
Notes | PMID:9705112 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 95 | ||
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Author | Blokland, A. | ||||
Title | Reaction time responding in rats | Type | Journal Article | ||
Year | 1998 | Publication | Neuroscience and Biobehavioral Reviews | Abbreviated Journal | Neurosci Biobehav Rev |
Volume | 22 | Issue | 6 | Pages | 847-864 |
Keywords | Amphetamine/pharmacology; Animals; Behavior, Animal/drug effects/*physiology; Conditioning, Operant/drug effects/*physiology; Dopamine Uptake Inhibitors/pharmacology; Dose-Response Relationship, Drug; Male; Rats; Rats, Inbred Lew; Reaction Time/drug effects/*physiology | ||||
Abstract | The use of reaction time has a great tradition in the field of human information processing research. In animal research the use of reaction time test paradigms is mainly limited to two research fields: the role of the striatum in movement initiation; and aging. It was discussed that reaction time responding can be regarded as “single behavior”, this term was used to indicate that only one behavioral category is measured, allowing a better analysis of brain-behavior relationships. Reaction time studies investigating the role of the striatum in motor functions revealed that the initiation of a behavioral response is dependent on the interaction of different neurotransmitters (viz. dopamine, glutamate, GABA). Studies in which lesions were made in different brain structures suggested that motor initiation is dependent on defined brain structures (e.g. medialldorsal striatum, prefrontal cortex). It was concluded that the use of reaction time measures can indeed be a powerful tool in studying brain-behavior relationships. However, there are some methodological constraints with respect to the assessment of reaction time in rats, as was tried to exemplify by the experiments described in the present paper. On the one hand one should try to control for behavioral characteristics of rats that may affect the validity of the parameter reaction time. On the other hand, the mean value of reaction time should be in the range of what has been reported in man. Although these criteria were not always met in several studies, it was concluded that reaction time can be validly assessed in rats. Finally, it was discussed that the use of reaction time may go beyond studies that investigate the role of the basal ganglia in motor output. Since response latency is a direct measure of information processing this parameter may provide insight into basic elements of cognition. Based on the significance of reaction times in human studies the use of this dependent variable in rats may provide a fruitful approach in studying brain-behavior relationships in cognitive functions. | ||||
Address | Department of Psychology, University of Maastricht, The Netherlands | ||||
Corporate Author | Thesis | ||||
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Language | English | Summary Language | Original Title | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0149-7634 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:9809315 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2807 | ||
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Author | Blunden, A.S.; Smith, K.C.; Whitwell, K.E.; Dunn, K.A. | ||||
Title | Systemic infection by equid herpesvirus-1 in a Grevy's zebra stallion (Equus grevyi) with particular reference to genital pathology | Type | Journal Article | ||
Year | 1998 | Publication | Journal of Comparative Pathology | Abbreviated Journal | J Comp Pathol |
Volume | 119 | Issue | 4 | Pages | 485-493 |
Keywords | Animals; Animals, Zoo; Epididymis/pathology/virology; Equidae/*virology; Herpesviridae Infections/diagnosis/pathology/*veterinary; Herpesvirus 1, Equid/isolation & purification/*pathogenicity; Lymph Nodes/pathology/virology; Male; Nasal Mucosa/pathology/virology; Pulmonary Edema/pathology; Spleen/virology; Testis/*pathology/virology | ||||
Abstract | A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto undescribed aspects of the pathogenesis of naturally occurring EHV-1 infection in the male equine genital tract. Restriction digests of the isolate demonstrated a pattern similar to that of EHV-1 isolates previously recovered from aborted zebra and onager fetuses. | ||||
Address | Animal Health Trust Centre for Preventive Medicine, Newmarket, Suffolk, UK | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-9975 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:9839210 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2239 | ||
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Author | Granquist,S.M.; Sigurjónsdóttir, H; Thórhallsdóttir, A.G. | ||||
Title | Social structure and interactions within groups of horses containing a stallion | Type | Conference Article | ||
Year | 2008 | Publication | IESM 2008 | Abbreviated Journal | |
Volume | Issue | Pages | |||
Keywords | Social interactions,, Stallions, Hierarchy, Icelandic horses | ||||
Abstract | Earlier research indicates that stallions might either prevent social interactions between mares in their herds directly or indirectly by their presence (Feist and McCullough, 1976; Sigurjonsdottir et al., 2003) The impact of stallions on the social interactions between harem members was studied in 6 groups of Icelandic horses in 2004, 2006 and 2007 for altogether 525 hours. Four of the groups were permanently living together under semi-feral conditions, while two were temporary breeding groups. In addition, temporary and permanent groups were compared and the effect of the stability of the group on the social behaviour of horses was investigated . The results show that stallions seldom intervene directly in social interactions between harem members. However, the hierarchies were less rigid and fewer friendship bonds were found in the groups compared to what has been found in groups without stallions in Iceland. These results give some support to our prediction that the stallion does indirectly suppress social interactions of herd members. The stability of the group was found to affect the aggression rate, since a higher aggression rate was found in the temporary groups compared to the permanent groups. The number of preferred allogrooming partners of the horses was also affected to some extent, as a significantly lower number of allogrooming partners was found in the most unstable group compared to all the other groups. The results have significance for further research in the field of social structure of mammals, and may also be applied in the management of horses and other domestic animals. |
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Address | |||||
Corporate Author | Sigurjónsdóttir, H | Thesis | |||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
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ISSN | ISBN | Medium | |||
Area | Expedition | Conference | IESM 2008 | ||
Notes | Talk 15 min IESM 2008 Fullpaper | Approved | yes | ||
Call Number | Equine Behaviour @ team @ | Serial | 4487 | ||
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