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Effects of tromethamine buffer on coagulation variables and ionized calcium concentration in dogs.
1997
Moon P.F. | Barr S.C. | Erb H.N.
Pharmacokinetics of heparin and its pharmacodynamic effect on plasma lipoprotein lipase activity and coagulation in healthy horses.
1995
McCann M.E. | Watson T.D.G. | Boudinot F.D. | Moore J.N.
We evaluated the pharmacokinetics of IV administered sodium heparin and the pharmacodynamic effect of heparin on lipoprotein lipase (LPL) activity Horses were allotted to 3 groups. Plasma samples were obtained from each horse before and at various times for 6 hours after heparin administration for determination of heparin concentration, LPL activity, and activated partial thromboplastin time (APTT). The disposition of heparin was dose dependent. The area under the plasma heparin concentration vs time curve (AUC) increased more than proportionally with dose, indicating that heparin elimination was nonlinear. Total clearance of heparin was similar after the 40 and 80 IU/kg of body weight dosages, averaging 0.45 and 0.36 IU/kg/min, respectively. However, after administration of the 120 IU/kg dose, clearance was significantly less than that after the 40 IU/kg dose. The half-life of heparin averaged 53, 70, and 136 minutes after 40, 80, and 120 IU/kg, respectively, with significant differences observed between the low and high doses. In contrast to heparin, the area under the plasma concentration vs time curve for LPL activity increased less than proportionally with dose. Maximal LPL activity observed was independent of dose, averaging 4.8 micromole of free fatty acids/ml/h. The APTT was significantly prolonged for 120 minutes after administration of the 40 IU/kg dose. Correlation coefficients for LPL activity vs either plasma heparin concentration or APTT were less than 0.7, indicating that neither laboratory measure can be used to accurately predict plasma LPL activity.
Afficher plus [+] Moins [-]Attempt to pharmacologically modulate procoagulant activity of lipopolysaccharide-stimulated adherent bovine alveolar macrophages.
1996
Olchowy T.W.J. | Dean D.F. | Bochsler P.N.
Prothrombotic events in the prodromal stages of acute laminitis in horses.
1995
Weiss D.J. | Trent A.M. | Johnston G.
Prothrombotic changes occurring in the prodromal stages of carbohydrate-induced laminitis were investigated. Hemostatic alterations were evaluated by determining platelet counts, platelet survival, activated partial thromboplastin time, one-stage prothrombin time, and monocyte procoagulant activity. Thrombosis of vessels in the hoof wall was evaluated by contrast arteriography and histologic examination. Of 5 horses, 4 became lame between 28 and 52 hours after carbohydrate administration. Mean platelet count in laminitis-affected horses was lower throughout the prodromal stages of laminitis, compared with that in control horses, but differences were not statistically significant. However, survival of indium-111-labeled platelets was less than the value in control horses by 6 hours after carbohydrate administration. Arteriography of disarticulated feet revealed marked reduction in blood supply to hooves in laminitis-affected horses. Histologic examination of the laminar dermis disclosed microthrombi in venules of the laminar dermis in 2 of 4 affected horses. Statistically significant changes in prothrombin time were not observed, and changes in activated partial thromboplastin time were slight and occurred only at the onset of lameness. Statistically significant changes in monocyte procoagulant activity were not observed. Plasma endotoxin-like activity was not detected in laminitis-affected horses. These data indicate that platelet survival was decreased within the first 6 hours after induction of carbohydrate-induced laminitis, but systemic activation of the coagulation system was not detected.
Afficher plus [+] Moins [-]Experimental trichothecene (T-2) toxicosis in Korean native goats.
1988
Kim J.S.
To investigate the effects of T-2 toxin on the blastogenesis of lymphocytes, pathology, hemogram and blood chemistry in the goat, the Korean native goats were treated orally with T-2 toxin for 21 days with a dosage of 0.6mg per kg body weight. The total count of leukocytes and lymphocytes decreased significantly from 14 to 21 days after treatment. Myeloid : erythroid ratios increased significantly on days 12 after treatment Delayed-type hypersensitivity skin reactions to tuberculin were reduced predominantly. T-2 toxin induced prolonged prothrombin time. Mitogenic responses of lymphocytes to both lipopolysaccharide and phytohemagglutinin were significantly depressed on days 7 and 14 after treatment. Treatment of T-2 toxin caused marked depletion of lymphocytes in the thymus, mesenteric lymph node, Peyer's patches and spleen.
Afficher plus [+] Moins [-]2-DE-MS based proteomic investigation of dairy cows with footrot
2016
Introduction: The differentially expressed proteins between healthy cows and those with footrot were identified to explore changes in protein profiles associated with the disease. Material and Methods: Out of 36 cows selected for the experiment, 18 footrot-affected cows were included in the treatment group (group T) and 18 unaffected cows were included in the control group (group C). Plasma samples from groups T and C were subjected to two-dimensional electrophoresis analysis and differentially expressed proteins were identified by matrix-assisted laser desorption/ionisation tandem time-of-flight mass spectrometry. Bioinformatics, including gene ontology analysis and pathway analysis, was used for analysing all proteins. Results: Out of 63 spots identified by 2DE, 33 were selected for mass spectrum analysis, which identified 11 differentially expressed proteins in 26 spots. Footrot led to changes in profiles in plasma proteins that were classified to the pathway of inflammatory response, complement, and blood coagulation, among others. Conclusion: This study provides evidence of the defence mechanisms of cows with footrot to explore strategies for treatment.
Afficher plus [+] Moins [-]The effects of oral administration of Yunnan Baiyao on blood coagulation in beagle dogs as measured by kaolin-activated thromboelastography and buccal mucosal bleeding times
2017
Frederick, John | Boysen, S. | Wagg, C. | Chalhoub, S.
We examined the effects of oral administration of Yunnan Baiyao (YB) on hemostasis by measuring buccal mucosal bleeding times (BMBTs) and doing citrated kaolin-activated whole-blood thromboelastography (TEG). In a randomized controlled crossover trial 8 beagle dogs were given either placebo or 1000 mg of YB orally every 12 h for 5 consecutive treatments. Blood was drawn 24 h before treatment and 2 and 24 h after the last treatment, and the BMBT was measured in each sample in duplicate. The TEG analysis was done in duplicate 60 ± 5 min after sample collection. There were no adverse effects of treatment and no significant differences between the control and treatment BMBTs or TEG parameters at any time point. Significant differences were found between baseline and 24 h after the last treatment within the treatment group for the TEG parameters LY30 and LY60 and within the control group for the TEG parameters MA, G, LY30, and LY60. Thus, at the dose and frequency of administration in this study YB did not appear to have any clinically significant effects on the measured coagulation parameters. The differences within the treatment group were likely due to analytic error since similar differences were seen in the control group. Further studies with a larger sample, as well as more direct measures of platelet function, are needed.
Afficher plus [+] Moins [-]Renal, gastrointestinal, and hemostatic effects of oral administration of meloxicam to Hispaniolan Amazon parrots (Amazona ventralis)
2015
Dijkstra, Bas | Sanchez-Migallon Guzman, David | Gustavsen, Kate | Owens, Sean D. | Hass, Carlyle | Kass, Philip H. | Paul-Murphy, Joanne R.
OBJECTIVE To investigate renal, gastrointestinal, and hemostatic effects associated with oral administration of multiple doses of meloxicam to healthy Hispaniolan Amazon parrots (Amazona ventralis). ANIMALS 12 Hispaniolan Amazon parrots. PROCEDURES Birds were assigned to receive meloxicam oral suspension (1.6 mg/kg, PO, q 12 h) and 2.5 mL of tap water inserted into the crop by use of a gavage tube (n = 8) or the equivalent volume of tap water only (control group; 4) for 15 days. Urine and feces were collected 2 hours after treatment administration each day. Feces were evaluated for occult blood. Results of a CBC and serum biochemical analysis and measured N-acetyl-β-d-glucosaminidase (NAG) activity and whole blood clotting time were evaluated before, during, and after completion of treatments. Results of urinalysis and measured urine NAG activity were also evaluated. RESULTS Birds treated with meloxicam had a significant increase in number of WBCs and decrease in PCV from before to after treatment. The PCV also decreased significantly, compared with results for the control group; however, WBC count and PCV for all birds remained within reference ranges throughout the study. One parrot treated with meloxicam had a single high value for urine NAG activity. CONCLUSIONS AND CLINICAL RELEVANCE Meloxicam administered orally at the dosage used in this study caused no apparent negative changes in several renal, gastrointestinal, or hemostatic variables in healthy Hispaniolan Amazon parrots. Additional studies to evaluate adverse effects of NSAIDs in birds will be needed.
Afficher plus [+] Moins [-]Blood coagulopathy in dogs with shock induced by injection of heartworm extract
1994
Kitoh, K. | Watoh, K. | Kitagawa, H. | Sasaki, Y.
A crude, whole-body extract of female heartworms was administered IV to 10 dogs with and 13 dogs without heartworm (HW) infection. Shock developed in 8 of 10 infected dogs and 11 of 13 non-infected dogs, and blood coagulopathy was observed in 12 of 19 dogs with shock. Prevalence and severity of blood coagulopathy were proportionate to prevalence and severity of shock. Platelet count decreased in all dogs with shock with or without blood coagulopathy; thus, the decrease in platelet count might be related to shock. In 4 dogs, activated partial thromboplastin time (APTT) was prolonged--192.0 seconds at 30 minutes after HW injection--and prothrombin time (PT) was increased--13.8 seconds at initial collapse. In 8 dogs, APTT was increased--200 seconds for 2 hours after HW injection--and PT was increased--200 seconds at 30 minutes after the injection. The APTT prolongation might have been caused mainly by decreases in activities of factors VIII, IX, XI, and XII of the intrinsic blood coagulation pathway. In dogs with severely prolonged PT, plasma fibrinogen concentration and factor II activity decreased slightly. Prolonged PT was corrected in vitro by addition of normal plasma at high concentration (> 80%), but prolonged APTT could not be corrected in vitro by addition of 80% normal plasma. Serum fibrin degradation products concentration was < 10 microgram/ml, and soluble fibrin monomer complex was negative in all dogs. Thrombi were not found in blood vessels of any organ at necropsy and after histologic study. Therefore, it was suggested that blood coagulopathy resulting from inhibition of coagulation factor activities might develop in shock induced by HW extract.
Afficher plus [+] Moins [-]Ferula communis variety brevifolia intoxication of sheep
1994
Tligui, N. | Ruth, G.R.
Sheep given powdered Ferula communis variety brevifolia at dosage of 2.5 g/kg of body weight/d for 15 days developed classical clinical signs of intoxication: anorexia, somnolence, apparent weakness, and hemorrhage. Marked reduction of vitamin K-dependent coagulation factors and prolongation of prothrombin time and activated partial thromboplastin time were consistent with presence of ferulenol, a toxic coumarinic factor in the plant. Changes induced in the coagulation system developed by the second day of plant administration and were normal within 4 days after dosing was stopped. There was no evidence of primary liver damage or platelet malfunction. Of 6 intoxicated sheep, 2 died with only minimal evidence of hemorrhage.
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