Records |
Author |
Linklater, W.L.; Cameron, E.Z.; Stafford, K.J.; Veltman, C.J. |
Title |
Social and spatial structure and range use by Kaimanawa wild horses (Equus caballus: Equidae) |
Type |
Journal Article |
Year |
2000 |
Publication |
New Zealand Journal of Ecology |
Abbreviated Journal |
New Zealand J. Ecol. |
Volume |
24 |
Issue |
2 |
Pages |
139-152 |
Keywords |
Bachelor male; Band; Density; Habitat use; Home range; Management proposals; Micro-climate; Vegetation monitoring; habitat use; home range; mammal; social structure; spatial distribution; New Zealand; Equus caballus |
Abstract |
We measured horse density, social structure, habitat use, home ranges and altitudinal micro-climates in the south-western Kaimanawa ranges east of Waiouru, New Zealand. Horse density in the Auahitotara ecological sector averaged 3.6 horses.km-2 and ranged from 0.9 to 5.2 horses.km-2 within different zones. The population's social structure was like that of other feral horse populations with an even adult sex ratio, year round breeding groups (bands) with stable adult membership consisting of 1 to 11 mares, 1 to 4 stallions, and their predispersal offspring, and bachelor groups with unstable membership. Bands and bachelor males were loyal to undefended home ranges with central core use areas. Band home range sizes varied positively with adult band size. Home ranges overlapped entirely with other home ranges. Horses were more likely to occupy north facing aspects, short tussock vegetation and flush zones and avoid high altitudes, southern aspects, steeper slopes, bare ground and forest remnants. Horses were more likely to be on north facing aspects, steeper slopes, in exotic and red tussock grasslands and flush zones during winter and at lower altitudes and on gentler slopes in spring and summer. Seasonal shifts by bands to river basin and stream valley floors in spring and higher altitudes in autumn and winter are attributed to the beginning of foaling and mating in spring and formation of frost inversion layers in winter. Given horse habitat selectivity and the presence of other ungulate herbivores, results from present exclosures are likely to exaggerate the size of horse impacts on range vegetation. Proposals to manage the population by relocation and confinement are likely to modify current social structure and range use behaviour and may lead to the need for more intensive management in the longer term. |
Address |
Ecology Group, Institute of Natural Resources, Massey University, Private Bag 11-222, Palmerston North, New Zealand |
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01106465 (Issn) |
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Cited By (since 1996): 12; Export Date: 21 April 2007; Source: Scopus; Language of Original Document: English; Correspondence Address: Linklater, W.L.; Ecology Group; Institute of Natural Resources; Massey University; Private Bag 11-222 Palmerston North, New Zealand; email: wlinklater@hotmail.com |
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refbase @ user @ |
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793 |
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Author |
Machnik, M.; Hegger, I.; Kietzmann, M.; Thevis, M.; Guddat, S.; Schanzer, W. |
Title |
Pharmacokinetics of altrenogest in horses |
Type |
Journal Article |
Year |
2007 |
Publication |
Journal of Veterinary Pharmacology and Therapeutics |
Abbreviated Journal |
J Vet Pharmacol Ther |
Volume |
30 |
Issue |
1 |
Pages |
86-90 |
Keywords |
Administration, Oral; Animals; Chromatography, Liquid/veterinary; Doping in Sports/prevention & control; Horses/*metabolism; Male; Mass Spectrometry/veterinary; Progesterone Congeners/administration & dosage/blood/*pharmacokinetics/urine; Reproducibility of Results; Substance Abuse Detection/veterinary; Trenbolone/administration & dosage/*analogs & derivatives/blood/pharmacokinetics/urine |
Abstract |
The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentrations were measured by liquid chromatography-tandem mass spectrometry. The plasma levels of altrenogest reached maximal concentrations of 23-75 ng/mL. Baseline values were achieved within 3 days after the final administration. Urine peak concentrations of total altrenogest ranged from 823 to 3895 ng/mL. Twelve days after the final administration concentrations were below the limit of detection (ca 2 ng/mL). |
Address |
Institute of Biochemistry, German Sport University, Cologne, Germany. m.machnik@biochem.dshs-koeln.de |
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0140-7783 |
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PMID:17217407 |
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1841 |
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Nicol, C.J.; Yoon, M.; Ward, J.M.; Yamashita, M.; Fukamachi, K.; Peters, J.M.; Gonzalez, F.J. |
Title |
PPARgamma influences susceptibility to DMBA-induced mammary, ovarian and skin carcinogenesis |
Type |
Journal Article |
Year |
2004 |
Publication |
Carcinogenesis |
Abbreviated Journal |
Carcinogenesis |
Volume |
25 |
Issue |
9 |
Pages |
1747-1755 |
Keywords |
9,10-Dimethyl-1,2-benzanthracene/*toxicity; Animals; DNA Primers/chemistry; Disease Susceptibility; Female; Heterozygote; Humans; Mammary Neoplasms, Experimental/chemically induced/*pathology; Mice; Ovarian Neoplasms/chemically induced/*pathology; RNA, Messenger/genetics/metabolism; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Reverse Transcriptase Polymerase Chain Reaction; Skin Neoplasms/chemically induced/*pathology; Survival Rate; Transcription Factors/genetics/*physiology; Zinc Fingers |
Abstract |
Peroxisome proliferator-activated receptor gamma (PPARgamma), a member of the nuclear receptor superfamily, plays a role in adipocyte differentiation, type II diabetes, macrophage response to inflammation and is suggested to influence carcinogen-induced colon cancer. Studies done in vitro and in vivo also revealed that PPARgamma ligands might promote differentiation and/or regression of mammary tumors. To directly evaluate the role of PPARgamma in mammary carcinogenesis, PPARgamma wild-type (+/+) or heterozygous (+/-) mice were administered 1 mg 7,12-dimethylbenz[a]anthracene (DMBA) by gavage once a week for 6 weeks and followed for a total of 25 weeks. Compared with congenic PPARgamma(+/+) littermate controls, PPARgamma(+/-) mice had early evidence for increased susceptibility to DMBA-mediated carcinogenesis based on a 1.6-fold increase in the percentage of mice with skin papillomas, as well as a 1.7-fold increase in the numbers of skin papillomas per mouse (P < 0.05). Similarly, PPARgamma(+/-) mice also had a 1.5-fold decreased survival rate (P = 0.059), and a 1.7-fold increased incidence of total tumors per mouse (P < 0.01). Moreover, PPARgamma(+/-) mice had an almost 3-fold increase in mammary adenocarcinomas (P < 0.05), an over 3-fold increase in ovarian granulosa cell carcinomas (P < 0.05), an over 3-fold increase in malignant tumors (P < 0.02) and a 4.6-fold increase in metastatic incidence. These results are the first to demonstrate an increased susceptibility in vivo of PPARgamma haploinsufficiency to DMBA-mediated carcinogenesis and suggest that PPARgamma may act as a tumor modifier of skin, ovarian and breast cancers. The data also support evidence suggesting a beneficial role for PPARgamma-specific ligands in the chemoprevention of mammary, ovarian and skin carcinogenesis. |
Address |
Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA |
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0143-3334 |
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PMID:15073042 |
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no |
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refbase @ user @ |
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76 |
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Author |
Seyfarth, R.M.; Cheney, D.L. |
Title |
Cognitive strategies and the representation of social relations by monkeys |
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Journal Article |
Year |
2001 |
Publication |
Nebraska Symposium on Motivation. Nebraska Symposium on Motivation |
Abbreviated Journal |
Nebr Symp Motiv |
Volume |
47 |
Issue |
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Pages |
145-177 |
Keywords |
Adaptation, Biological; Animals; *Evolution; Family; Female; Haplorhini; Male; Memory; Primates; *Selection (Genetics); *Social Behavior; Social Dominance; *Social Perception |
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University of Pennsylvania, USA |
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0146-7875 |
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PMID:11759347 |
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no |
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refbase @ user @ |
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345 |
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Author |
Zentall, S.S.; Zentall, T.R. |
Title |
Hyperactivity ratings: statistical regression provides an insufficient explanation of practice effects |
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Journal Article |
Year |
1986 |
Publication |
Journal of pediatric psychology |
Abbreviated Journal |
J Pediatr Psychol |
Volume |
11 |
Issue |
3 |
Pages |
393-396 |
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Attention Deficit Disorder with Hyperactivity/*diagnosis; Child; Humans; Male; *Practice (Psychology); *Statistics |
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0146-8693 |
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PMID:3772683 |
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refbase @ user @ |
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261 |
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Nelson, D.M.; Gardner, I.A.; Chiles, R.F.; Balasuriya, U.B.; Eldridge, B.F.; Scott, T.W.; Reisen, W.K.; James Maclachlan, N. |
Title |
Prevalence of antibodies against Saint Louis encephalitis and Jamestown Canyon viruses in California horses |
Type |
Journal Article |
Year |
2004 |
Publication |
Comparative Immunology, Microbiology and Infectious Diseases |
Abbreviated Journal |
Comp Immunol Microbiol Infect Dis |
Volume |
27 |
Issue |
3 |
Pages |
209-215 |
Keywords |
Animals; Antibodies, Viral/*blood; California/epidemiology; Encephalitis Virus, California/*immunology/isolation & purification; Encephalitis Virus, St. Louis/*immunology/isolation & purification; Encephalitis, St. Louis/epidemiology/immunology/*veterinary/virology; Female; Horse Diseases/epidemiology/immunology/*virology; Horses; Logistic Models; Male; Neutralization Tests/veterinary; Polyomavirus Infections/epidemiology/immunology/*veterinary/virology; Questionnaires; Seroepidemiologic Studies; Tumor Virus Infections/epidemiology/immunology/*veterinary/virology |
Abstract |
Jamestown Canyon (JC) and Saint Louis encephalitis (SLE) viruses are mosquito-transmitted viruses that have long been present in California. The objective of this study was to determine the seroprevalence of these two viruses in horses prior to the introduction of West Nile (WN) virus. Approximately 15% of serum samples collected in 1998 from 425 horses on 44 equine operations horses throughout California had serum antibodies to JC virus, whereas antibodies were not detected to SLE virus. The results indicate that horses in California were commonly infected prior to 1998 with mosquito-transmitted Bunyaviruses that are identical or closely related to JC virus, but not with SLE virus. The different seroprevalence of SLE and JC viruses in horses likely reflects the unique ecology of each virus, and it is predicted that WN virus will have a wider distribution in California than closely related SLE virus. |
Address |
Animal and Plant Health Inspection Service, Veterinary Services, U.S. Department of Agriculture, California and Nevada Area Office, 9850 Micron Avenue, Suite E, Sacramento, CA 95827, USA |
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0147-9571 |
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PMID:15001316 |
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Equine Behaviour @ team @ |
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2637 |
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Author |
Hemelrijk, C.K.; Wantia, J. |
Title |
Individual variation by self-organisation |
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Journal Article |
Year |
2005 |
Publication |
Neuroscience and biobehavioral reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
Volume |
29 |
Issue |
1 |
Pages |
125-136 |
Keywords |
Aggression; Animals; Behavior, Animal/*physiology; Competitive Behavior/*physiology; Female; Humans; *Individuality; Male; Models, Psychological; Sex Characteristics; *Social Dominance; Time Factors |
Abstract |
In this paper, we show that differences in dominance and spatial centrality of individuals in a group may arise through self-organisation. Our instrument is a model, called DomWorld, that represents two traits that are often found in animals, namely grouping and competing. In this model individual differences grow under the following conditions: (1) when the intensity of aggression increases and grouping becomes denser, (2) when the degree of sexual dimorphism in fighting power increases. In this case the differences among females compared to males grow too, (3) when, upon encountering another individual, the tendency to attack is 'obligate' and not conditional, namely 'sensitive to risks'. Results resemble phenomena described for societies of primates, mice, birds and pigs. |
Address |
Theoretical Biology, University of Groningen, NN Haren, The Netherlands. hemelrij@ifi.unizh.ch |
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0149-7634 |
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PMID:15652260 |
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refbase @ user @ |
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443 |
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Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W. |
Title |
Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy |
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Journal Article |
Year |
2002 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
Volume |
26 |
Issue |
6 |
Pages |
679-695 |
Keywords |
Age Factors; Aging/*physiology; Analysis of Variance; Animals; Antioxidants/*pharmacology; Blood Chemical Analysis/methods; Cognition/*physiology; *Diet; Discrimination Learning/*drug effects/*physiology; Distance Perception/drug effects/physiology; Dogs/physiology; Female; Male; Psychomotor Performance/physiology; Retention (Psychology)/drug effects/physiology; Spatial Behavior/*drug effects/*physiology; Task Performance and Analysis; Time Factors; Vitamin E/blood |
Abstract |
The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition. |
Address |
Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca |
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0149-7634 |
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PMID:12479842 |
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Equine Behaviour @ team @ |
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2806 |
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Author |
Blokland, A. |
Title |
Reaction time responding in rats |
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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 |
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0149-7634 |
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PMID:9809315 |
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Equine Behaviour @ team @ |
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2807 |
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Carroll, G.L.; Matthews, N.S.; Hartsfield, S.M.; Slater, M.R.; Champney, T.H.; Erickson, S.W. |
Title |
The effect of detomidine and its antagonism with tolazoline on stress-related hormones, metabolites, physiologic responses, and behavior in awake ponies |
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Journal Article |
Year |
1997 |
Publication |
Veterinary surgery : VS : the official journal of the American College of Veterinary Surgeons |
Abbreviated Journal |
Vet Surg |
Volume |
26 |
Issue |
1 |
Pages |
69-77 |
Keywords |
Adrenergic alpha-Antagonists/administration & dosage/*pharmacology; Animals; Behavior, Animal/drug effects/physiology; Blood Glucose/metabolism; Blood Pressure/drug effects/physiology; Consciousness/physiology; Dose-Response Relationship, Drug; Drug Interactions; Epinephrine/blood; Fatty Acids, Nonesterified/blood; Female; Heart Rate/drug effects/physiology; Horse Diseases/metabolism/physiopathology/psychology; Horses/blood/metabolism/*physiology; Hydrocortisone/blood; Hypnotics and Sedatives/administration & dosage/*pharmacology; Imidazoles/administration & dosage/*pharmacology; Injections, Intravenous; Male; Norepinephrine/blood; Receptors, Adrenergic, alpha/drug effects/*physiology; Stress/metabolism/physiopathology/veterinary; Time Factors; Tolazoline/administration & dosage/*pharmacology |
Abstract |
Six ponies were used to investigate the effect of tolazoline antagonism of detomidine on physiological responses, behavior, epinephrine, norepinephrine, cortisol, glucose, and free fatty acids in awake ponies. Each pony had a catheter inserted into a jugular vein 1 hour before beginning the study. Awake ponies were administered detomidine (0.04 mg/kg intravenously [i.v.]) followed 20 minutes later by either tolazoline (4.0 mg/kg i.v.) or saline. Blood samples were drawn from the catheter 5 minutes before detomidine administration (baseline), 5 minutes after detomidine administration, 20 minutes before detomidine administration which was immediately before the administration of tolazoline or saline (time [T] = 0), and at 5, 30, and 60 minutes after injections of tolazoline or saline (T = 5, 30, and 60 minutes, respectively). Compared with heart rate at T = 0, tolazoline antagonism increased heart rate 45% at 5 minutes. There was no difference in heart rate between treatments at 30 minutes. Blood pressure remained stable after tolazoline, while it decreased over time after saline. Compared with concentrations at T = 0, tolazoline antagonism of detomidine in awake ponies resulted in a 55% increase in cortisol at 30 minutes and a 52% increase in glucose at 5 minutes. The change in free fatty acids was different for tolazoline and saline over time. Free fatty acids decreased after detomidine administration. Free fatty acids did not change after saline administration. After tolazoline administration, free fatty acids increased transiently. Tolazoline tended to decrease sedation and analgesia at 15 and 60 minutes postantagonism. Antagonism of detomidine-induced physiological and behavioral effects with tolazoline in awake ponies that were not experiencing pain appears to precipitate a stress response as measured by cortisol, glucose, and free fatty acids. If antagonism of an alpha-agonist is contemplated, the potential effect on hormones and metabolites should be considered. |
Address |
Department of Small Animal Medicine and Surgery, Texas A&M University, College Station, USA |
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0161-3499 |
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PMID:9123816 |
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refbase @ user @ |
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96 |
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