Records |
Author |
Lansade, L.; Bertrand, M.; Bouissou, M.-F. |
Title |
Effects of neonatal handling on subsequent manageability, reactivity and learning ability of foals |
Type |
Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
Volume |
92 |
Issue |
1-2 |
Pages |
143-158 |
Keywords |
Horse; Neonatal handling; Manageability; Emotional reactivity; Learning-ability; Human-animal relationship |
Abstract |
Behaviour is an important factor to be taken into account in the various uses of horses. Today horses are mainly used for sport and leisure activities. They should therefore be easy to manage, calm and not fearful. Early handling is known to improve manageability and learning ability and to reduce fearfulness in various species. It has become fashionable in the horse industry to use an early training procedure, referred to as “imprint training”, which is said to produce durable if not permanent effects. However, no studies concerning the long-term effects of such neonatal handling have been carried out in horses. The present study examines the short- and long-term effects of neonatal handling on manageability, general reactivity and learning ability of foals. Twenty-six Welsh foals were studied: 13 were handled daily for 14 days from birth and 13 were non-handled controls. The handling procedure consisted of fitting a halter, gently patting all parts of each foal's body, picking up feet and leading over 40 m. Two days, 3 months, 6 months and 1 year after the end of the handling period, foals underwent behavioural tests to measure their manageability and various aspects of their reactivity. The results showed that neonatal handling has only short-term effects on manageability: 2 days after the handling period, handled animals were significantly easier to handle than controls for the four parameters measured during this test (time to fit a halter, time to pick up feet, walk ratio that is time during which foal walks under constraint/total time measured during leading and number of defensive reactions). Two parameters (time to fit a halter and walk ratio) were still lower in handled foals than in non-handled foals 3 months later and only one 6 months later (walk ratio). One year later there was no difference between groups. In addition, there was no effect of handling on reactivity at any time of testing or in any of the tests (reaction to isolation from conspecifics, presence of a human, presence of a novel object and to a surprise effect). Finally, neonatal handling did not improve the spatial or discriminative learning abilities measured at 14 months of age. To conclude, the effects of neonatal handling are only temporary. |
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refbase @ user @ |
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841 |
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Husted, L.; Andersen, M.S.; Borggaard, O.K.; Houe, H.; Olsen, S.N. |
Title |
Risk factors for faecal sand excretion in Icelandic horses |
Type |
Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
Volume |
37 |
Issue |
4 |
Pages |
351-355 |
Keywords |
Animal Feed; Animal Husbandry/methods; Animals; Denmark; Feces/*chemistry; Female; Gastrointestinal Diseases/epidemiology/etiology/prevention & control/veterinary; Horse Diseases/epidemiology/etiology/prevention & control; Horses/*metabolism; Logistic Models; Male; Pilot Projects; *Poaceae/growth & development; Risk Factors; Silicon Dioxide/administration & dosage/adverse effects/*analysis; Soil/*analysis |
Abstract |
REASONS FOR PERFORMING STUDY: Sandy soil is often mentioned as a risk factor in the development of sand-related gastrointestinal disease (SGID) in the horse. There are other variables, but few studies confirm any of these. OBJECTIVE: To investigate soil type, pasture quality, feeding practice in the paddock, age, sex and body condition score as risk factors for sand intake in the horse. METHODS: Faeces were collected from 211 Icelandic horses on 19 different studs in Denmark together with soil samples and other potential risk factors. Sand content in faeces determined by a sand sedimentation test was interpreted as evidence of sand intake. Soil types were identified by soil analysis and significance of the data was tested using logistic analysis. RESULTS: Of horses included in the study, 56.4% showed sand in the faeces and 5.7% had more than 5 mm sand as quantified by the rectal sleeve sedimentation test. Soil type had no significant effect when tested as main effect, but there was interaction between soil type and pasture quality. Significant interactions were also found between paddock feeding practice and pasture quality. CONCLUSION: To evaluate the risk of sand intake it is important to consider 3 variables: soil type, pasture quality and feeding practice. Pasture quality was identified as a risk factor of both short and long grass in combination with sandy soil, while clay soil had the lowest risk in these combinations. Feeding practice in the paddock revealed feeding directly on the ground to be a risk factor when there was short (1-5 cm) or no grass. Also, no feeding outdoors increased the risk on pastures with short grass, while this had no effect in paddocks with no grass. More than 50% of all horses investigated in this study had sand in the faeces. POTENTIAL RELEVANCE: The identification of risk factors is an important step towards prevention of SGID. Further research is necessary to determine why some horses exhibit more than 5 mm sand in the sedimentation test and whether this is correlated with geophagic behaviour. |
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Department of Large Animal Sciences, The Royal Veterinary and Agricultural University, Dyrlaegevej 88, DK-1870 Frederiksberg, Denmark |
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0425-1644 |
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PMID:16028626 |
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Call Number |
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Serial |
1888 |
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Author |
Grogan, E.H.; McDonnell, S.M. |
Title |
Behavioral responses to two intranasal vaccine applicators in horses and ponies |
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Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Journal of the American Veterinary Medical Association |
Abbreviated Journal |
J Am Vet Med Assoc |
Volume |
226 |
Issue |
10 |
Pages |
1689-1693 |
Keywords |
Administration, Intranasal; Animals; *Behavior, Animal; Female; Horses/physiology/*psychology; Immunization/instrumentation/methods/*veterinary; Male; Patient Compliance/psychology; Physical Examination/psychology/*veterinary; Vaccines/*administration & dosage; Videotape Recording |
Abstract |
OBJECTIVE: To evaluate behavioral compliance of horses and ponies with simulated intranasal vaccination and assess development of generalized aversion to veterinary manipulations. DESIGN: Clinical trial. ANIMALS: 28 light horse mares, 3 pony geldings, 2 light horse stallions, and 3 pony stallions that had a history of compliance with veterinary procedures. PROCEDURE: Behavioral compliance with 2 intranasal vaccine applicators was assessed. Compliance with standard physical examination procedures was assessed before and after a single experience with either of the applicators or a control manipulation to evaluate development of generalized aversion to veterinary manipulation. RESULTS: In all 30 horses, simulated intranasal vaccination or the control manipulation could be performed without problematic avoidance behavior, and simulated intranasal vaccination did not have any significant effect on duration of or compliance with a standardized physical examination that included manipulation of the ears, nose, and mouth. Results were similar for the 2 intranasal vaccine applicators, and no difference in compliance was seen between horses in which warm versus cold applicators were used. For 3 of the 6 ponies, substantial avoidance behavior was observed in association with simulated intranasal vaccination, and compliance with physical examination procedures decreased after simulated intranasal vaccination. CONCLUSIONS AND CLINICAL RELEVANCE: Although some compliance problems were seen with ponies, neither problems with compliance with simulated intranasal vaccination nor adverse effects on subsequent physical examination were identified in any of the horses. Further study is needed to understand factors involved in practitioner reports of aversion developing in association with intranasal vaccination. |
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Equine Behavior Laboratory, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA |
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0003-1488 |
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PMID:15906570 |
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no |
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1890 |
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Kendal, R.L.; Coe, R.L.; Laland, K.N. |
Title |
Age differences in neophilia, exploration, and innovation in family groups of callitrichid monkeys |
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Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
Volume |
66 |
Issue |
2 |
Pages |
167-188 |
Keywords |
Age Factors; Analysis of Variance; Animals; *Animals, Zoo; Behavior, Animal/*physiology; Callitrichinae/*physiology; *Creativeness; Exploratory Behavior/*physiology; Observation; Social Behavior; Task Performance and Analysis |
Abstract |
The prevailing assumption in the primate literature is that young or juvenile primates are more innovative than adult individuals. This innovative tendency among the young is frequently thought to be a consequence, or side effect, of their increased rates of exploration and play. Conversely, Reader and Laland's [International Journal of Primatology 22:787-806, 2001] review of the primate innovation literature noted a greater reported incidence of innovation in adults than nonadults, which they interpreted as (in part) a reflection of the greater experience and competence of older individuals. Within callitrichids there is contradictory evidence for age differences in response to novel objects, foods, and foraging tasks. By presenting novel extractive foraging tasks to family groups of callitrichid monkeys in zoos, we examined, in a large sample, whether there are positive or negative relationships of age with neophilia, exploration, and innovation, and whether play or experience most facilitates innovation. The results indicate that exploration and innovation (but not neophilia) are positively correlated with age, perhaps reflecting adults' greater manipulative competence. To the extent that there was evidence for play in younger individuals, it did not appear to contribute to innovation. The implications of these findings for the fields of innovation and conservation through reintroduction are considered. |
Address |
Sub-Department of Animal Behavior, University of Cambridge, Cambridge, UK. RachelKendal2003@yahoo.co.uk |
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0275-2565 |
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PMID:15940712 |
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2148 |
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Author |
Borsari, A.; Ottoni, E.B. |
Title |
Preliminary observations of tool use in captive hyacinth macaws (Anodorhynchus hyacinthinus) |
Type |
Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
Volume |
8 |
Issue |
1 |
Pages |
48-52 |
Keywords |
Age Factors; Animals; *Feeding Behavior; Female; *Intelligence; Male; *Motor Skills; *Nuts; *Parrots |
Abstract |
Many animals use tools (detached objects applied to another object to produce an alteration in shape, position, or structure) in foraging, for instance, to access encapsulated food. Descriptions of tool use by hyacinth macaws (Anodorhynchus hyacinthinus) are scarce and brief. In order to describe one case of such behavior, six captive birds were observed while feeding. Differences in nut manipulation and opening proficiency between adults and juveniles were recorded. The tools may be serving as a wedge, preventing the nut from slipping and/or rotating, reducing the impact of opening, or providing mechanical aid in its positioning and/or use of force. Data suggest that birds of this species have an innate tendency to use objects (tools) as aids during nut manipulation and opening. |
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Laboratory of Cognitive Ethology, Department of Experimental Psychology, Institute of Psychology, University of Sao Paulo, Sao Paulo, Brazil. borsari@hotmail.com |
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1435-9448 |
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PMID:15248094 |
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no |
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Equine Behaviour @ team @ |
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2518 |
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Author |
Watson, L.H.; Odendaal, H.E.; Barry, T.J.; Pietersen, J. |
Title |
Population viability of Cape mountain zebra in Gamka Mountain Nature Reserve, South Africa: the influence of habitat and fire |
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Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Biological Conservation |
Abbreviated Journal |
Biol. Conserva. |
Volume |
122 |
Issue |
2 |
Pages |
173-180 |
Keywords |
Mountain zebra; Population viability analysis; Habitat suitability; Fire; Conservation management |
Abstract |
The small Cape mountain zebra population in Gamka Mountain Nature Reserve represents a third of the entire gene pool of this endangered species and is thus vital for it's conservation. Presently, management of this population is largely hands off, with the belief that it will grow to levels which will allow it to form a source for the mixing of mountain zebra stocks in the future. The growth of this population however, has been slow and we investigated the influence of habitat and fire on this growth. Firstly, we used a diffusion model to perform a population viability analysis. This analysis indicated that the population had a low probability of attaining quasi-extinction in the next 50 years (G = 0.0032). However, our findings indicated that less than 30% of the reserve was suitable for mountain zebra and that the preferred habitat would have to be burnt at unnaturally short intervals to sustain the present growth. We therefore argue that the risk of quasi-extinction to this population is greater than predicted and suggest that management options need to be implemented to reduce this risk. These options include; translocation to another protected area; acquisition of adjacent land; burning preferred habitat at unnaturally short intervals; forming a conservancy with adjacent landowners; leasing cultivated land for pasture. We suggest that only the latter two options are likely to stimulate mountain zebra population growth in the short term and that these should receive immediate attention. |
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Equine Behaviour @ team @ |
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3547 |
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Author |
Santamaria, S.; Bobbert, M.F.; Back, W.; Barneveld, A.; van Weeren, P.R. |
Title |
Effect of early training on the jumping technique of horses |
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Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
Volume |
66 |
Issue |
3 |
Pages |
418-424 |
Keywords |
Age Factors; Analysis of Variance; Animals; Biomechanics; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/growth & development/*physiology; Locomotion/*physiology; Models, Biological; Physical Conditioning, Animal/*methods |
Abstract |
OBJECTIVE: To investigate the effects of early training for jumping by comparing the jumping technique of horses that had received early training with that of horses raised conventionally. ANIMALS: 40 Dutch Warmblood horses. PROCEDURE: The horses were analyzed kinematically during free jumping at 6 months of age. Subsequently, they were allocated into a control group that was raised conventionally and an experimental group that received 30 months of early training starting at 6 months of age. At 4 years of age, after a period of rest in pasture and a short period of training with a rider, both groups were analyzed kinematically during free jumping. Subsequently, both groups started a 1-year intensive training for jumping, and at 5 years of age, they were again analyzed kinematically during free jumping. In addition, the horses competed in a puissance competition to test maximal performance. RESULTS: Whereas there were no differences in jumping technique between experimental and control horses at 6 months of age, at 4 years, the experimental horses jumped in a more effective manner than the control horses; they raised their center of gravity less yet cleared more fences successfully than the control horses. However, at 5 years of age, these differences were not detected. Furthermore, the experimental horses did not perform better than the control horses in the puissance competition. CONCLUSIONS AND CLINICAL RELEVANCE: Specific training for jumping of horses at an early age is unnecessary because the effects on jumping technique and jumping capacity are not permanent. |
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Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, NL-3584 CM Utrecht, The Netherlands |
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0002-9645 |
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PMID:15822585 |
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no |
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Equine Behaviour @ team @ |
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4037 |
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Author |
Thiel, D.; Jenni-Eiermann, S.; Palme, R. |
Title |
Measuring corticosterone metabolites in droppings of capercaillies (Tetrao urogallus) |
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Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2005 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann N Y Acad Sci |
Volume |
1046 |
Issue |
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Pages |
96-108 |
Keywords |
Adrenocorticotropic Hormone/administration & dosage/analysis/metabolism; Animals; Circadian Rhythm; Corticosterone/administration & dosage/*analysis/*metabolism; Feces/*chemistry; Female; Freezing; Galliformes/*metabolism; Male; Reproducibility of Results; Sex Factors; Temperature; Time Factors; Tritium/diagnostic use |
Abstract |
The capercaillie (Tetrao urogallus), the largest grouse species in the world, is decreasing in numbers in major parts of its distribution range. Disturbances by human outdoor activities are discussed as a possible reason for this population decline. An indicator for disturbances is the increase of the glucocorticoid corticosterone, a stress hormone, which helps to cope with life-threatening situations. However, repeated disturbances might result in a long-term increase of the basal corticosterone concentration, which can result in detrimental effects like reduced fitness and survival of an animal. To measure corticosterone metabolites (CMs) noninvasively in the droppings of free-living capercaillies, first an enzyme immunoassay (EIA) in captive birds had to be selected and validated. Therefore, the excretion pattern of intravenously injected radiolabeled corticosterone was determined and 3H metabolites were characterized. High-performance liquid chromatography (HPLC) separations of the samples containing peak concentrations revealed that corticosterone was extensively metabolized. The HPLC fractions were tested in several EIAs for glucocorticoid metabolites. The physiological relevance of this method was proved after pharmacological stimulation of the adrenocortical activity. Only the recently established cortisone assay, measuring CMs with a 3,11-dione structure, detected an expressed increase of concentrations following ACTH stimulation. To set up a sampling protocol suited for the field, we examined the influence of various storage conditions and time of day on concentrations of CMs. |
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Swiss Ornithological Institute, 6204 Sempach, Switzerland. dominik.thiel@vogelwarte.ch |
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0077-8923 |
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PMID:16055846 |
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Equine Behaviour @ team @ |
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4079 |
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Author |
Jeong, S.; Han, M.; Lee, H.; Kim, M.; Kim, J.; Nicol, C.J.; Kim, B.H.; Choi, J.H.; Nam, K.-H.; Oh, G.T.; Yoon, M. |
Title |
Effects of fenofibrate on high-fat diet-induced body weight gain and adiposity in female C57BL/6J mice |
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Journal Article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2004 |
Publication |
Metabolism: clinical and experimental |
Abbreviated Journal |
Metabolism |
Volume |
53 |
Issue |
10 |
Pages |
1284-1289 |
Keywords |
Adipose Tissue/*anatomy & histology/drug effects; Animals; Antilipemic Agents/*pharmacology; Body Composition/*drug effects; Body Weight/drug effects; Dietary Fats/*pharmacology; Eating/drug effects; Fatty Acids/metabolism; Female; Gene Expression Regulation/drug effects; Leptin/metabolism; Liver/metabolism; Mice; Mice, Inbred C57BL; Ovariectomy; Procetofen/*pharmacology; RNA, Messenger/biosynthesis/genetics; Receptors, Cytoplasmic and Nuclear/biosynthesis/genetics/metabolism; Transcription Factors/biosynthesis/genetics/metabolism; Weight Gain/*drug effects |
Abstract |
Our previous study suggested that fenofibrate affects obesity and lipid metabolism in a sexually dimorphic manner in part through the differential activation of hepatic peroxisome proliferator-activated receptor alpha (PPARalpha) in male and female C57BL/6J mice. To determine whether fenofibrate reduces body weight gain and adiposity in female sham-operated (Sham) and ovariectomized (OVX) C57BL/6J mice, the effects of fenofibrate on not only body weight, white adipose tissue (WAT) mass, and food intake, but also the expression of both leptin and PPARalpha target genes were measured. Compared to their respective low-fat diet-fed controls, both Sham and OVX mice exhibited increases in body weight and WAT mass when fed a high-fat diet. Fenofibrate treatment decreased body weight gain and WAT mass in OVX, but not in Sham mice. Furthermore, fenofibrate increased the mRNA levels of PPARalpha target genes encoding peroxisomal enzymes involved in fatty acid beta-oxidation, and reduced apolipoprotein C-III (apo C-III) mRNA, all of which were expressed at higher levels in OVX compared to Sham mice. However, leptin mRNA levels were found to positively correlate with WAT mass, and food intake was not changed in either OVX or Sham mice following fenofibrate treatment. These results suggest that fenofibrate differentially regulates body weight and adiposity due in part to differences in PPARalpha activation, but not to differences in leptin production, between female OVX and Sham mice. |
Address |
Department of Life Sciences, Mokwon University, Taejon, Korea |
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0026-0495 |
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PMID:15375783 |
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no |
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refbase @ user @ |
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72 |
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Author |
Cheung, C.; Akiyama, T.E.; Ward, J.M.; Nicol, C.J.; Feigenbaum, L.; Vinson, C.; Gonzalez, F.J. |
Title |
Diminished hepatocellular proliferation in mice humanized for the nuclear receptor peroxisome proliferator-activated receptor alpha |
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Journal Article |
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2004 |
Publication |
Cancer research |
Abbreviated Journal |
Cancer Res |
Volume |
64 |
Issue |
11 |
Pages |
3849-3854 |
Keywords |
Animals; Anticholesteremic Agents/pharmacology; Carcinogens/pharmacology; Cell Division; DNA Replication/drug effects; Fatty Acids/metabolism; Hepatocytes/cytology/drug effects/metabolism/*physiology; Humans; Mice; Mice, Transgenic; Oxidation-Reduction; Peroxisome Proliferators/pharmacology; Pyrimidines/pharmacology; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Species Specificity; Transcription Factors/genetics/*physiology |
Abstract |
Lipid-lowering fibrate drugs function as agonists for the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha). Sustained activation of PPARalpha leads to the development of liver tumors in rats and mice. However, humans appear to be resistant to the induction of peroxisome proliferation and the development of liver cancer by fibrate drugs. The molecular basis of this species difference is not known. To examine the mechanism determining species differences in peroxisome proliferator response between mice and humans, a PPARalpha-humanized mouse line was generated in which the human PPARalpha was expressed in liver under control of the tetracycline responsive regulatory system. The PPARalpha-humanized and wild-type mice responded to treatment with the potent PPARalpha ligand Wy-14643 as revealed by induction of genes encoding peroxisomal and mitochondrial fatty acid metabolizing enzymes and resultant decrease of serum triglycerides. However, surprisingly, only the wild-type mice and not the PPARalpha-humanized mice exhibited hepatocellular proliferation as revealed by elevation of cell cycle control genes, increased incorporation of 5-bromo-2'-deoxyuridine into hepatocyte nuclei, and hepatomegaly. These studies establish that following ligand activation, the PPARalpha-mediated pathways controlling lipid metabolism are independent from those controlling the cell proliferation pathways. These findings also suggest that structural differences between human and mouse PPARalpha are responsible for the differential susceptibility to the development of hepatocarcinomas observed after treatment with fibrates. The PPARalpha-humanized mice should serve as models for use in drug development and human risk assessment and to determine the mechanism of hepatocarcinogenesis of peroxisome proliferators. |
Address |
Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
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0008-5472 |
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PMID:15172993 |
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refbase @ user @ |
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74 |
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