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Author |
Loyola, E.G.; Rodriguez, M.H.; Gonzalez, L.; Arredondo, J.I.; Bown, D.N.; Vaca, M.A. |
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Title |
Effect of indoor residual spraying of DDT and bendiocarb on the feeding patterns of Anopheles pseudopunctipennis in Mexico |
Type |
Journal Article |
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Year |
1990 |
Publication |
Journal of the American Mosquito Control Association |
Abbreviated Journal |
J Am Mosq Control Assoc |
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Volume |
6 |
Issue  |
4 |
Pages |
635-640 |
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Keywords |
Animals; Anopheles/*physiology; *Carbamates; Cattle; *Ddt; Ecology; Enzyme-Linked Immunosorbent Assay; Feeding Behavior/*drug effects; Horses; Humans; Insect Vectors; Insecticide Resistance; *Insecticides; Mexico; *Phenylcarbamates; Seasons |
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Abstract |
Intense and persistent use of DDT for malaria control has increased resistance and induced exophilic behavior of Anopheles pseudopunctipennis. An evaluation of bendiocarb and DDT to control this species in Sinaloa, Mexico, showed that, in spite of DDT-resistance, both insecticides produced similar effects. Feeding patterns were analyzed to explain these results. Resting mosquitoes were collected over the dry and wet seasons. Anophelines were tested in an ELISA to determine the source of the meals. The human blood index (HBI) ranged from 3.3 to 6.8% in DDT- and from 12.7 to 26.9% in bendiocarb-sprayed houses. Irritability and repellency in DDT-sprayed houses could explain the reduced HBI. In contrast, bendiocarb produced higher mortality. These effects could have affected different components of the vectorial capacity and similarly reduced malaria. |
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Center for Malaria Research, Chiapas, Mexico |
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English |
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8756-971X |
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PMID:2098469 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2671 |
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Author |
Nicol, C.J.; Adachi, M.; Akiyama, T.E.; Gonzalez, F.J. |
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Title |
PPARgamma in endothelial cells influences high fat diet-induced hypertension |
Type |
Journal Article |
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Year |
2005 |
Publication |
American journal of hypertension : journal of the American Society of Hypertension |
Abbreviated Journal |
Am J Hypertens |
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Volume |
18 |
Issue |
4 Pt 1 |
Pages |
549-556 |
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Keywords |
Administration, Oral; Animals; Antihypertensive Agents/pharmacology; Blood Pressure/drug effects; Diabetes Mellitus, Type 2/physiopathology; Dietary Fats/*administration & dosage/pharmacology; Dose-Response Relationship, Drug; Endothelial Cells/*metabolism; Female; Heart Rate/drug effects; Hypertension/*etiology; Ligands; Male; Mice; Mice, Knockout; PPAR gamma/*metabolism; Sodium Chloride/administration & dosage/pharmacology; Thiazolidinediones/pharmacology |
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Abstract |
BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands improve human hypertension. However, the mechanism and site of this effect remains unknown, confounded by PPARgamma expression in many cell types, including endothelial cells (ECs). METHODS: To evaluate the vascular role of PPARgamma we used a conditional null mouse model. Specific disruption of PPARgamma in ECs was created by crossing Tie2-Cre+ transgenic (T2T+) and PPARgamma-floxed (fl/fl) mice to generate PPARgamma (fl/fl)T2T+ (PPARgamma E-null) mice. Conscious 8- to 12-week-old congenic PPARgamma (fl/fl)Cre- (wild type) and PPARgamma E-null mice were examined for changes in systolic blood pressure (BP) and heart rate (HR), untreated, after 2 months of salt-loading (drinking water), and after treatment for 3 months with high fat (HF) diet alone or supplemented during the last 2 weeks with rosiglitazone (3 mg/kg/d). RESULTS: Untreated PPARgamma E-nulls were phenotypically indistinguishable from wild-type littermates. However, compared to similarly treated wild types, HF-treated PPARgamma E-nulls had significantly elevated systolic BP not seen after normal diet or salt-loading. Despite sex-dependent baseline differences, salt-loaded and HF-treated PPARgamma E-nulls of either sex had significantly elevated HR versus wild types. Interestingly, rosiglitazone improved serum insulin levels, but not HF diet-induced hypertension, in PPARgamma E-null mice. CONCLUSIONS: These results suggest that PPARgamma in ECs not only is an important regulator of hypertension and HR under stressed conditions mimicking those arising in type 2 diabetics, but also mediates the antihypertensive effects of rosiglitazone. These data add evidence supporting a beneficial role for PPARgamma-specific ligands in the treatment of hypertension, and suggest therapeutic strategies targeting ECs may prove useful. |
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Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
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0895-7061 |
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Notes |
PMID:15831367 |
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no |
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Call Number |
refbase @ user @ |
Serial |
69 |
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Author |
Rietmann, T.R.; Stauffacher, M.; Bernasconi, P.; Auer, J.A.; Weishaupt, M.A. |
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Title |
The association between heart rate, heart rate variability, endocrine and behavioural pain measures in horses suffering from laminitis |
Type |
Journal Article |
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Year |
2004 |
Publication |
Journal of Veterinary Medicine. A, Physiology, Pathology, Clinical Medicine |
Abbreviated Journal |
J Vet Med A Physiol Pathol Clin Med |
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Volume |
51 |
Issue |
5 |
Pages |
218-225 |
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Keywords |
Animals; Anti-Inflammatory Agents, Non-Steroidal/administration & dosage; Autonomic Nervous System; Behavior, Animal; Electrophysiology/*methods; Endocrine System; Female; Heart Rate; Horse Diseases/blood/drug therapy/*physiopathology; Horses; Joint Diseases/physiopathology/*veterinary; Male; Pain/physiopathology/*veterinary; Pain Measurement/*veterinary; Predictive Value of Tests |
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Abstract |
The objective of this study was to compare the stress response of horses suffering from laminitis after short- and long-term treatment with the intent to evaluate power spectral analysis of heart rate variability (HRV) for pain monitoring. Data were collected from 19 horses with acute or chronic exacerbating laminitis without known primary disease before and after treatment with non-steroidal anti-inflammatory drugs (NSAID). Recordings were carried out the day after admission to the equine hospital. Measurements were repeated on day 7 of the treatment. The recorded parameters included a clinical orthopaedic index (OLPI: Obel-grade plus hoof tester score), frequency of weight-shifting between contralateral limbs, mean beat-to-beat interval (R-R) duration, standard deviation of continuous R-R intervals, low- (LF) and high-frequency (HF) components of HRV, sympatho-vagal balance (LF/HF), and plasma concentration of cortisol, adrenalin and noradrenalin. The LF represents mainly sympathetic influences on the heart whereas HF is mediated by the parasympathetic tone. Weight-shifting and OLPI decreased significantly with treatment. The LF normalized units (n.u.) decreased after NSAID from 60.41 +/- 21.42 to 51.12 +/- 19.81 and was 49.33 +/- 22.64 on day 7, whereas HF n.u. increased from 35.07 +/- 20.02 to 43.14 +/- 18.30 and was 45.98 +/- 23.00 on day 7. Hormone levels showed no tendency to change with treatment. The OLPI was only correlated with LF/HF, LF and HF (R = 0.57, 0.55 and -0.54 respectively). Significant negative correlations existed between HFn.u. and weight-shifting frequency (R = -0.37), HFn.u. and adrenalin (R = -0.47), and HFn.u. and noradrenalin (R = 0.33). The LFn.u. only correlated positively with adrenalin. Cortisol levels were poorly associated with the other parameters. Determination of the sympatho-vagal influences on cardiac function may offer complementary information for reliable assessment of pain and may represent a valuable alternative method to catecholamine measurements. |
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Equine Hospital, Faculty of Veterinary Medicine, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland |
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0931-184X |
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Notes |
PMID:15315700 |
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no |
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Call Number |
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Serial |
1899 |
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Author |
Pierce, M.M.; Nall, B.T. |
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Title |
Coupled kinetic traps in cytochrome c folding: His-heme misligation and proline isomerization |
Type |
Journal Article |
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Year |
2000 |
Publication |
Journal of Molecular Biology |
Abbreviated Journal |
J Mol Biol |
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Volume |
298 |
Issue |
5 |
Pages |
955-969 |
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Keywords |
Amino Acid Sequence; Amino Acid Substitution/genetics; Binding Sites; Cytochrome c Group/*chemistry/genetics/*metabolism; *Cytochromes c; Enzyme Stability/drug effects; Fluorescence; Guanidine/pharmacology; Heme/*metabolism; Histidine/genetics/*metabolism; Hydrogen-Ion Concentration; Isomerism; Kinetics; Models, Molecular; Molecular Sequence Data; Mutation/genetics; Proline/*chemistry/metabolism; Protein Conformation/drug effects; Protein Denaturation/drug effects; *Protein Folding; Protein Renaturation; Saccharomyces cerevisiae/enzymology/genetics; Sequence Alignment; Thermodynamics |
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Abstract |
The effect of His-heme misligation on folding has been investigated for a triple mutant of yeast iso-2 cytochrome c (N26H,H33N,H39K iso-2). The variant contains a single misligating His residue at position 26, a location at which His residues are found in several cytochrome c homologues, including horse, tuna, and yeast iso-1. The amplitude for fast phase folding exhibits a strong initial pH dependence. For GdnHCl unfolded protein at an initial pH<5, the observed refolding at final pH 6 is dominated by a fast phase (tau(2f)=20 ms, alpha(2f)=90 %) that represents folding in the absence of misligation. For unfolded protein at initial pH 6, folding at final pH 6 occurs in a fast phase of reduced amplitude (alpha(2f) approximately 20 %) but the same rate (tau(2f)=20 ms), and in two slower phases (tau(m)=6-8 seconds, alpha(m) approximately 45 %; and tau(1b)=16-20 seconds, alpha(1b) approximately 35 %). Double jump experiments show that the initial pH dependence of the folding amplitudes results from a slow pH-dependent equilibrium between fast and slow folding species present in the unfolded protein. The slow equilibrium arises from coupling of the His protonation equilibrium to His-heme misligation and proline isomerization. Specifically, Pro25 is predominantly in trans in the unligated low-pH unfolded protein, but is constrained in a non-native cis isomerization state by His26-heme misligation near neutral pH. Refolding from the misligated unfolded form proceeds slowly due to the large energetic barrier required for proline isomerization and displacement of the misligated His26-heme ligand. |
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Center for Biomolecular Structure, Department of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA |
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English |
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ISSN |
0022-2836 |
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Notes |
PMID:10801361 |
Approved |
no |
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Call Number |
refbase @ user @ |
Serial |
3853 |
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Author |
Pennisi, E. |
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Title |
Schizophrenia clues from monkeys |
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Year |
1997 |
Publication |
Science (New York, N.Y.) |
Abbreviated Journal |
Science |
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Volume |
277 |
Issue |
5328 |
Pages |
900 |
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Keywords |
Animals; Antipsychotic Agents/pharmacology; Behavior, Animal/drug effects; *Cercopithecus aethiops; Clozapine/pharmacology; Cognition/drug effects; *Disease Models, Animal; Dopamine/*metabolism; Excitatory Amino Acid Antagonists/pharmacology; Memory/drug effects; Phencyclidine/*pharmacology; Prefrontal Cortex/*metabolism; Schizophrenia/chemically induced/drug therapy/*metabolism; Schizophrenic Psychology |
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English |
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ISSN |
0036-8075 |
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PMID:9281070 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2844 |
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Author |
Houpt, K.A.; Northrup, N.; Wheatley, T.; Houpt, T.R. |
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Title |
Thirst and salt appetite in horses treated with furosemide |
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Journal Article |
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Year |
1991 |
Publication |
Journal of applied physiology (Bethesda, Md. : 1985) |
Abbreviated Journal |
J Appl Physiol |
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Volume |
71 |
Issue |
6 |
Pages |
2380-2386 |
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Keywords |
Animals; Appetite/*drug effects; Blood Volume; Diuresis; Drinking/drug effects; Female; Furosemide/*pharmacology; Horses; Natriuresis; Sodium, Dietary/*administration & dosage; Thirst/*drug effects |
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Abstract |
When a preliminary experiment in sodium-replete ponies revealed an increase, but not a significant increase, in salt consumption after furosemide treatment, the experiment was repeated using sodium-deficient horses in which aldosterone levels might be expected to be elevated to test the hypothesis that a background of aldosterone is necessary for salt appetite. Ten Standardbred mares were injected intravenously with furosemide or an equivalent volume of 0.9% sodium chloride as a control to test the effect of furosemide on their salt appetite and blood constituents. Sodium intake and sodium loss in urine, as well as water intake and urine output, were measured and compared to determine accuracy of compensation for natriuresis and diuresis. Plasma protein and packed cell volume showed significant increases in response to furosemide treatment (F = 29.31, P less than 0.001 and F = 11.20, P less than 0.001, respectively). There were no significant changes in plasma sodium concentration or osmolality in response to the treatment (P greater than 0.05). The furosemide-treated horses consumed 126 +/- 14.8 g salt, significantly more than when they were given the control injection (94.5 +/- 9.8 g; t = 2.22, P = 0.05). In response to furosemide, horses lost 962 +/- 79.7 and consumed 2,170 +/- 5 meq sodium; however, compared with control, they lost 955 meq more sodium and ingested only 570 meq more sodium, so they were undercompensating for natriuresis. The furosemide-treated horses drank 9.6 +/- 0.8 kg of water, significantly more than when they received the control injection (6.4 +/- 0.8 kg; t = 6.9, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) |
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Department of Physiology, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853-6401 |
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ISSN |
8750-7587 |
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Notes |
PMID:1778936 |
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no |
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Call Number |
refbase @ user @ |
Serial |
38 |
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Author |
Grubb, T.L.; Foreman, J.H.; Benson, G.J.; Thurmon, J.C.; Tranquilli, W.J.; Constable, P.D.; Olson, W.O.; Davis, L.E. |
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Title |
Hemodynamic effects of calcium gluconate administered to conscious horses |
Type |
Journal Article |
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Year |
1996 |
Publication |
Journal of veterinary internal medicine / American College of Veterinary Internal Medicine |
Abbreviated Journal |
J Vet Intern Med |
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Volume |
10 |
Issue |
6 |
Pages |
401-404 |
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Keywords |
Animals; Blood Pressure/drug effects/physiology; Calcium/blood; Calcium Gluconate/administration & dosage/*pharmacology; Cardiac Output/drug effects/physiology; Consciousness/*physiology; Dose-Response Relationship, Drug; Female; Heart Rate/drug effects/physiology; Hemodynamic Processes/*drug effects/physiology; Horses/blood/*physiology; Infusions, Intravenous; Male; Myocardial Contraction/drug effects/physiology; Respiration/drug effects/physiology; Stroke Volume/drug effects/physiology; Time Factors |
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Abstract |
Calcium gluconate was administered to conscious horses at 3 different rates (0.1, 0.2, and 0.4 mg/kg/min for 15 minutes each). Serum calcium concentrations and parameters of cardiovascular function were evaluated. All 3 calcium administration rates caused marked increases in both ionized and total calcium concentrations, cardiac index, stroke index, and cardiac contractility (dP/dtmax). Mean arterial pressure and right atrial pressure were unchanged; heart rate decreased markedly during calcium administration. Ionized calcium concentration remained between 54% and 57% of total calcium concentration throughout the study. We conclude that calcium gluconate can safely be administered to conscious horses at 0.1 to 0.4 mg/kg/min and that administration will result in improved cardiac function. |
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Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, USA |
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English |
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ISSN |
0891-6640 |
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Notes |
PMID:8947873 |
Approved |
no |
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Call Number |
refbase @ user @ |
Serial |
97 |
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Author |
Tavernor, W.D.; Lees, P. |
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Title |
A pharmacological investigation of the influence of suxamethonium on cardiac function in the horse |
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Journal Article |
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Year |
1968 |
Publication |
Experientia |
Abbreviated Journal |
Experientia |
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Volume |
24 |
Issue |
6 |
Pages |
582-583 |
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Keywords |
Animals; Arrhythmia/chemically induced; Consciousness; Halothane; Heart/innervation; Heart Rate/*drug effects; Horses/*physiology; Oxygen; Propranolol/pharmacology; Receptors, Sensory/drug effects; Stimulation, Chemical; Succinylcholine/antagonists & inhibitors/*pharmacology; Sympathetic Nervous System/physiology; Tachycardia/chemically induced; Thiopental |
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English |
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ISSN |
0014-4754 |
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Notes |
PMID:5697737 |
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no |
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Call Number |
refbase @ user @ |
Serial |
104 |
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Author |
Weik, H.; Altmann, J. |
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Title |
The effect of L(+)-lactate on rat and horse adipose tissue in vitro |
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Journal Article |
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Year |
1972 |
Publication |
Zentralblatt fur Veterinarmedizin. Reihe A |
Abbreviated Journal |
Zentralbl Veterinarmed A |
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Volume |
19 |
Issue |
6 |
Pages |
514-518 |
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Keywords |
Adipose Tissue/analysis/*drug effects; Animals; Fatty Acids, Nonesterified; Glycerol/metabolism; Horses; Lactates/*pharmacology; Lipid Metabolism; Male; Rats |
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English |
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ISSN |
0514-7158 |
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Notes |
PMID:4626300 |
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no |
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Call Number |
refbase @ user @ |
Serial |
132 |
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Author |
Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W. |
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Title |
Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy |
Type |
Journal Article |
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Year |
2002 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
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Volume |
26 |
Issue |
6 |
Pages |
679-695 |
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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 |
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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. |
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Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca |
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English |
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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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