首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 578 毫秒
1.
Objective-To evaluate hemodynamic effects in dogs after IM administration of dexmedetomidine (7.5 μg/kg, butorphanol (0.15 mg/kg), and tiletamine-zolazepam (3 mg/kg [DBTZ]) or dexmedetomidine (15 μg/kg), butorphanol (0.3 mg/kg), and ketamine (3 mg/kg [DBK]). Animals-5 healthy adult mixed-breed dogs. Procedures-Each dog received DBTZ and DBK in a randomized crossover study with a 48-hour interval between treatments. Anesthesia was induced and maintained with sevoflurane in 100% oxygen while instrumentation with Swan-Ganz and arterial catheters was performed. Following instrumentation, hemodynamic measurements were recorded at 3.54% (1.5 times the minimum alveolar concentration) sevoflurane; then sevoflurane administration was discontinued, and dogs were allowed to recover. Six hours after cessation of sevoflurane administration, baseline hemodynamic measurements were recorded, each dog was given an IM injection of DBTZ or DBK, and hemodynamic measurements were obtained at predetermined intervals for 70 minutes. Results-DBTZ and DBK induced hypoventilation (Paco(2), approx 60 to 70 mm Hg), respiratory acidosis (pH, approx 7.2), hypertension (mean arterial blood pressure, approx 115 to 174 mm Hg), increases in systemic vascular resistance, and reflex bradycardia. Cardiac output, oxygen delivery, and oxygen consumption following DBTZ or DBK administration were similar to those following sevoflurane administration to achieve a surgical plane of anesthesia. Blood l-lactate concentrations remained within the reference range at all times for all protocols. Conclusions and Clinical Relevance-In healthy dogs, both DBTZ and DBK maintained oxygen delivery and oxygen consumption to tissues and blood lactate concentrations within the reference range. However, ventilation should be carefully monitored and assisted when necessary to prevent hypoventilation.  相似文献   

2.
Oral tolerance tests were performed on 13 neonatal foals to determine their ability to digest disaccharides on d 1, 3 and 5 postpartum. Foals were assigned randomly to treatments consisting of 20% (wt/vol) solutions of either maltose, lactose, or sucrose, dosed at 1 g/kg of BW, or glucose, dosed at .5 g/kg of BW. After a 2-h fast, an initial blood sample was collected via jugular catheter. Foals were administered the appropriate solution orally, and blood was collected every 15 min for 1 h and then every 30 min for 3 h. Plasma glucose increased after dosing with lactose or glucose but not with sucrose. Plasma glucose concentrations increased slightly on d 3 and 5 in foals dosed with maltose. These findings suggest that although lactose is well digested by neonatal foals, maltose is digested only slightly, and sucrose is not digested by d 5. Results of this experiment indicate that maltose and sucrose would not be suitable for inclusion in artificial diets for foals less than 1 wk old. Oral tolerance tests could be useful for determining the ability of premature or sick foals with lactose intolerance to digest alternate carbohydrate sources.  相似文献   

3.
OBJECTIVE: To determine the effectiveness and safety of 2 sedative-analgesic protocols to facilitate assisted ventilation in healthy dogs. ANIMALS: 12 healthy dogs. PROCEDURES: Dogs were randomly assigned to 2 groups. Mean dosages for protocol 1 were diazepam (0.5 mg/kg/h [n = 3 dogs]) or midazolam (0.5 mg/kg/h [3]), morphine (0.6 mg/kg/h [6]), and medetomidine (1.0 microg/kg/h [6]). Mean dosages for protocol 2 were diazepam (0.5 mg/kg/h [n = 3]) or midazolam (0.5 mg/kg/h [3]), fentanyl (18 microg/kg/h [6]), and propofol (2.5 mg/kg/h [6]). Each dog received the drugs for 24 consecutive hours. All dogs were mechanically ventilated with adjustments in minute volume to maintain normocapnia and normoxemia. Cardiorespiratory variables were recorded. A numeric comfort score was assigned hourly to assess efficacy. Mouth care, position change, and physiotherapy were performed every 6 hours. Urine output was measured every 4 hours. RESULTS: Use of both protocols maintained dogs within optimal comfort ranges > 85% of the time. The first dog in each group was excluded from the study. Significant decreases in heart rate, oxygen consumption, and oxygen extraction ratio were evident for protocol 1. Cardiac index values in ventilated dogs were lower than values reported for healthy unsedated dogs. Oxygen delivery, lactate concentration, and arterial base excess remained within reference ranges for both protocols. CONCLUSIONS AND CLINICAL RELEVANCE: Use of both protocols was effective for facilitating mechanical ventilation. A reduction in cardiac index was detected for both protocols as a result of bradycardia. However, oxygen delivery and global tissue perfusion were not negatively affected.  相似文献   

4.
OBJECTIVE: To evaluate the effects of twice-daily oral administration of a low-dose of trilostane treatment and assess the duration of effects after once-daily trilostane administration in dogs with naturally occurring hyperadrenocorticism (NOH). DESIGN: Prospective study. ANIMALS: 28 dogs with NOH. PROCEDURES: 22 dogs received 0.5 to 2.5 mg of trilostane/kg (0.23 to 1.14 mg/lb) orally every 12 hours initially. At intervals, dogs were reevaluated; owner assessment of treatment response was recorded. To assess drug effect duration, 16 of the 22 dogs and 6 additional dogs underwent 2 ACTH stimulation tests 3 to 4 hours and 8 to 9 hours after once-daily trilostane administration. RESULTS: After 1 to 2 weeks, mean trilostane dosage was 1.4 mg/kg (0.64 mg/lb) every 12 hours (n = 22 dogs; good response [resolution of signs], 8; poor response, 14). Four to 8 weeks later, mean dosage was 1.8 mg/kg (0.82 mg/lb) every 12 or 8 hours (n = 21 and 1 dogs, respectively; good response, 15; poor response, 5; 2 dogs were ill). Eight to 16 weeks after the second reevaluation, remaining dogs had good responses (mean dosages, 1.9 mg/kg [0.86 mg/lb], q 12 h [n = 13 dogs] and 1.3 mg/kg [0.59 mg/lb], q 8 h [3]). At 3 to 4 hours and 8 to 9 hours after once-daily dosing, mean post-ACTH stimulation serum cortisol concentrations were 2.60 and 8.09 Pg/dL, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with NOH, administration of trilostane at low doses every 12 hours was effective, although 2 dogs became ill during treatment. Drug effects diminished within 8 to 9 hours. Because of potential adverse effects, lower doses should be evaluated.  相似文献   

5.
Pulmonary H2 excretion was measured in 10 healthy dogs, in 6 dogs with pancreatic exocrine insufficiency, and in 6 dogs with chronic small intestinal disease. Concentration of expired H2 in fasted healthy dogs was 0.9 +/- 0.1 ppm (mean +/- SEM) and peak H2 concentration of 1.4 +/- 0.2 ppm was detected up to 8 hours after feeding. Dogs with pancreatic exocrine insufficiency had fasting expired H2 concentrations of 3.3 +/- 0.9 ppm, which increased to a mean peak H2 concentration of 28.8 +/- 2.0 ppm 6.5 hours after feeding. Following xylose administration, expired H2 concentrations increased from fasting concentrations of 3.6 +/- 0.9 ppm to peak at 19.0 +/- 2.0 ppm in 1.5 hours. Blood xylose concentrations were diagnostic for carbohydrate malabsorption in 4 of 6 dogs with pancreatic exocrine insufficiency. Plasma p-aminobenzoic acid concentration identified bentiromide maldigestion in all dogs with pancreatic exocrine insufficiency. In 3 pancreatic exocrine insufficient dogs tested, pancreatic enzyme replacement therapy partially corrected carbohydrate malabsorption. Fasting expired H2 concentration was 5.3 +/- 1.3 ppm in dogs with chronic small intestinal disease and increased to a peak H2 of 72.2 +/- 18.0 ppm 7 hours after feeding. Following administration of xylose to dogs with chronic small intestinal disease, fasting expired H2 concentration increased from 3.0 +/- 1.0 ppm to a peak of 35.5 +/- 7.2 ppm at 2 hours. Blood xylose concentration was abnormal in only 2 of 6 dogs with chronic small intestinal disease. Results of these studies indicate that expired H2 analysis can identify carbohydrate malabsorption in dogs with pancreatic exocrine insufficiency or chronic small intestinal disease, and that pulmonary H2 testing is more sensitive than xylose absorption testing for the identification of carbohydrate malabsorption.  相似文献   

6.
OBJECTIVE: To determine the toxicity of ecadotril in dogs. ANIMALS: 74 healthy 4- to 11-month-old Beagles. PROCEDURE: To determine acute toxicity, ecadotril (2,000 mg/kg of body weight, PO) in a gelatin capsule was administered once to 2 dogs, and dogs were observed for 2 weeks. To determine subchronic and chronic toxicity, ecadotril was administered every day for 3 months (50 mg/kg [n = 8], 100 mg/kg [8], 300 mg/kg [12]) and 12 months (25 mg/kg [n = 8], 50 mg/kg [8], 100 mg/kg [8]), respectively. Dogs in control groups (n = 12 or 8) received an empty gelatin capsule. Physical examinations, CBC, plasma biochemical analyses, and urinalyses were performed before and at various times during each experiment. Dogs were euthanatized at the end of each experiment, and necropsies were performed. RESULTS: Dogs that received 1 dose of 2,000 mg of ecadotril/kg developed nonspecific clinical signs of toxicosis. Dogs that received 300 mg of ecadotril/kg/d for 3 months developed pronounced anemia, bone marrow suppression, and some evidence of liver impairment. There was no evidence of an effect accumulated over time, and reversibility of toxic effects was evident. Dogs that received < or =100 mg of ecadotril/kg/d for 3 or 12 months tolerated treatment without apparent effect. CONCLUSIONS AND CLINICAL RELEVANCE: Degree of acute toxicity of a single high dose of ecadotril in dogs was low. The no-observable adverse effect level of ecadotril following daily oral administration was 100 mg/kg/d; repeated administration of 300 mg/kg/d revealed the hematopoietic system as the primary toxicologic target.  相似文献   

7.
BACKGROUND: Glomerular filtration rate (GFR) measurement is an indicator of kidney function. However, its usefulness in dogs at early stages of spontaneous chronic kidney disease (CKD) of glomerular origin, where routine laboratory techniques are not sufficiently sensitive, remains unproved. HYPOTHESIS: That GFR is reduced in proteinuric nonazotemic or mildly azotemic dogs with CKD secondary to leishmaniasis. ANIMALS: Twenty-six dogs with CKD secondary to leishmaniasis and 10 healthy dogs (control group). METHODS: CBC, serum biochemistry, and urinalysis (microalbuminuria and urine protein/creatinine ratio [UPC]) were performed in all dogs. GFR was calculated by measuring exogenous creatinine clearance. Based on degree of proteinuria and serum creatinine concentration (SCr), dogs were classified as group A (control; n = 10): UPC < 0.2, SCr < 1.4 mg/dL; group B (n = 8): UPC, 0.2-0.5, SCr < 1.4 mg/dL; group C (n = 10): UPC > 0.5, SCr < 1.4 mg/dL; group D (n = 5): SCr, 1.4-2 mg/dL; group E (n = 3): SCr > 2 mg/dL. Results: GFR (mL/kg/min) was 3.9 +/- 0.29, 4.4 +/- 0.74, 4.5 +/- 1.44, 2.8 +/- 0.97, and 1.5 +/- 0.43 for groups A, B, C, D, and E, respectively. Eleven dogs (1 from group B, 3 from group C, 4 from group D, and all 3 dogs from group E) had an abnormally low GFR. Four dogs from group B and 5 dogs from group C had a GFR above the upper reference range (>4.5 mL/min/kg). CONCLUSION AND CLINICAL RELEVANCE: Some proteinuric nonazotemic or mildly azotemic dogs with leishmaniasis have low GFR, but glomerular hyperfiltration occurs in other dogs.  相似文献   

8.
OBJECTIVE: To investigate effects of short- and long- term administration of glucocorticoids, feeding status, and serum concentrations of insulin and cortisol on plasma leptin concentrations in dogs. ANIMALS: 20 nonobese dogs. PROCEDURE: For experiment 1, plasma leptin concentrations and serum concentrations of insulin and cortisol were monitored for 24 hours in 4 dogs administered dexamethasone (0.1 mg/kg, IV) or saline (0.9% NaCl) solution for fed and nonfed conditions. For experiment 2, 11 dogs were administered prednisolone (1 mg/kg, PO, q 24 h for 56 days [7 dogs] and 2 mg/kg, PO, q 24 h for 28 days [4 dogs]) and 5 dogs served as control dogs. Plasma leptin and serum insulin concentrations were monitored weekly. RESULTS: For experiment 1, dexamethasone injection with the fed condition drastically increased plasma leptin concentrations. Furthermore, injection of saline solution with the fed condition increased plasma leptin concentrations. These increases in plasma leptin concentrations correlated with increases in serum insulin concentrations. Dexamethasone injection with the nonfed condition increased plasma leptin concentrations slightly but continuously. Injection of saline solution with the nonfed condition did not alter plasma leptin concentrations. For experiment 2, prednisolone administration at either dosage and duration did not alter plasma leptin concentrations in any dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Dexamethasone injection and feeding increased plasma leptin concentrations in dogs. In addition, dexamethasone administration enhanced the effect of feeding on increases in plasma leptin concentrations. Daily oral administration of prednisolone (1 or 2 mg/kg) did not affect plasma leptin concentrations in dogs.  相似文献   

9.
OBJECTIVE: To describe the pharmacokinetics of cyclosporine (CyA) in healthy dogs after oral administration alone or in combination with orally administered cimetidine. ANIMALS: 10 healthy adult Beagles. PROCEDURE: Dogs were randomly assigned to receive CyA alone or CyA in combination with cimetidine. After a washout period of 2 weeks, dogs then received the alternate treatment. The CyA plus cimetidine treatment required administration of cimetidine (15 mg/kg of body weight, PO, q 8 h) for 8 days and administration of CyA (5 mg/kg, PO, q 24 h) on days 6 through 8. The CyA treatment alone required administration of CyA (5 mg/kg, PO, q 24 h) for 3 days. On the third day of CyA administration during each treatment, blood samples were collected immediately before (time 0) and 0.5, 1, 1.5, 2, 2.5, 3, 5, 7, 9, 11, 13, 15, 21, and 24 hours after initiating CyA administration. RESULTS: Time until maximum CyA concentration was significantly longer for CyA in combination with cimetidine. Assessment of estimated pharmacokinetic variables revealed a significantly faster rate of change in the distribution phase for CyA in combination with cimetidine. Maximum CyA concentration differed significantly among dogs but did not differ significantly between treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of our data suggests that cimetidine may affect absorption of orally administered CyA, but overall, it does not affect the pharmacokinetics of CyA. There is considerable variability in the maximum concentration of CyA among dogs, and monitoring of blood concentrations of CyA during treatment is advised.  相似文献   

10.
Background: The cytokine response in immune‐mediated hemolytic anemia (IMHA) is poorly characterized and correlation with outcome is unknown. Hypothesis/Objectives: To determine if cytokine activity is correlated with outcome in dogs with IMHA. Animals: Twenty dogs with primary IMHA and 6 control dogs. Methods: Prospective study on dogs with IMHA with blood sampling at admission. Serum activity of interleukin‐2 (IL‐2), IL‐4, IL‐6, IL‐7, IL‐8, IL‐10, IL‐15, IL‐18, monocyte chemoattractant protein‐1 (MCP‐1), granulocyte‐macrophage colony stimulating factor (GM‐CSF), interferon‐inducible protein‐10, interferon‐gamma, and keratinocyte chemoattractant (KC) was assessed. Results: Thirty‐day case fatality rate was 25% (5/20 dogs). Increased concentrations (median [range]) of IL‐2 (45.5 ng/L [0;830] versus 0 ng/L [0;46.8]), IL‐10 (8.2 ng/L [0;60.6] versus 0 ng/L [0;88.2]), KC (1.7 μg/L [0.3;4.7] versus 0.5 μg/L [0.2;1.1]), and MCP‐1 (162 ng/L [97.6;438] versus 124 ng/L [90.2;168]) were observed in dogs with IMHA compared with controls. The cytokine profile was indicative of a mixture of pro‐ and anti‐inflammatory cytokines of various cellular origins. Cytokines/chemokines strongly associated with macrophage/monocyte activation and recruitment were significantly increased in nonsurvivors compared with survivors; IL‐15 (179 ng/L [48.0;570] versus 21.3 ng/L [0;193]), IL‐18 (199 ng/L [58.7;915] versus 37.4 ng/L [0;128]), GM‐CSF (134 ng/L [70.0;863] versus 57.6 ng/L [0;164]), and MCP‐1 (219 ng/L [135;438] versus 159 ng/L [97.6;274]), respectively. Logistic regression suggested increased IL‐18 and MCP‐1 concentrations were independently associated with mortality in this population (P<.05, Wald's type 3). Conclusions and Clinical Importance: A mixed cytokine response is present in dogs with IMHA and mediators of macrophage activation and recruitment might serve as prognostic indicators.  相似文献   

11.
OBJECTIVE: To determine effects of preoperative administration of ketoprofen on whole blood platelet aggregation, buccal mucosal bleeding time, and hematologic indices in dogs after elective ovariohysterectomy. DESIGN: Randomized, masked clinical trial. ANIMALS: 22 healthy dogs. PROCEDURE: 60 minutes before induction of anesthesia, 11 dogs were given 0.9% NaCl solution (control), and 11 dogs were given ketoprofen (2 mg/kg [0.9 mg/lb], IM). Thirty minutes before induction of anesthesia, glycopyrrolate (0.01mg/kg [0.005 mg/lb]), acepromazine (0.05 mg/kg [0.02 mg/lb]), and butorphanol (0.2 mg/kg 10.09 mg/lb]) were given IM to all dogs. Anesthesia was induced with thiopental (5 to 10 mg/kg [2.3 to 4.5 mg/lb], IV) and maintained with isoflurane (1 to 3%). Ovariohysterectomy was performed and butorphanol (0.1 mg/kg [0.05 mg/lb], IV) was given 15 minutes before completion of surgery. Blood samples for measurement of variables were collected at intervals before and after surgery. RESULTS: In dogs given ketoprofen, platelet aggregation was decreased 95 +/- 10% and 80 +/- 35% (mean +/- SD) immediately after surgery and 24 hours after surgery, respectively, compared with preoperative values. At both times, mean values in dogs given ketoprofen differed significantly from those in control dogs. Significant differences between groups were not observed for mucosal bleeding time or hematologic indices. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative administration of ketoprofen inhibited platelet aggre gation but did not alter bleeding time. Ketoprofen can be given before surgery to healthy dogs undergoing elective ovariohysterectomy, provided that dogs are screened for potential bleeding problems before surgery and monitored closely after surgery.  相似文献   

12.
OBJECTIVE: To determine the cardiorespiratory effects of epidural administration of morphine alone and in combination with fentanyl in dogs anesthetized with sevoflurane. DESIGN: Prospective study. ANIMALS: 6 dogs. PROCEDURE: Dogs were anesthetized with sevoflurane and allowed to breathe spontaneously. After a stable plane of anesthesia was achieved, morphine (0.1 mg/kg [0.045 mg/lb]) or a combination of morphine and fentanyl (10 microg/kg [4.5 microg/lb]) was administered through an epidural catheter, the tip of which was positioned at the level of L6 or L7. Cardiorespiratory variables were measured for 90 minutes. RESULTS: Epidural administration of morphine alone did not cause any significant changes in cardiorespiratory measurements. However, epidural administration of morphine and fentanyl induced significant decreases in diastolic and mean arterial blood pressures and total peripheral resistance. Stroke volume was unchanged, PaCO2 was significantly increased, and arterial pH and base excess were significantly decreased. Heart rate was significantly lower after epidural administration of morphine and fentanyl than after administration of morphine alone. None of the dogs had any evidence of urine retention, vomiting, or pruritus after recovery from anesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that epidural administration of morphine at a dose of 0.1 mg/kg in combination with fentanyl at a dose of 10 microg/kg can cause cardiorespiratory depression in dogs anesthetized with sevoflurane.  相似文献   

13.
OBJECTIVE: To determine the effects of ketamine hydrochloride on hemodynamic and immunologic alterations associated with experimentally induced endotoxemia in dogs. ANIMALS: 9 mixed-breed dogs. PROCEDURES: In a crossover study, dogs were randomly allocated to receive ketamine (0.5 mg/kg, IV, followed by IV infusion at a rate of 0.12 mg/kg/h for 2.5 hours) or control solution (saline [0.9% NaCl] solution, 0.25 mL, IV, followed by IV infusion at a rate of 0.5 mL/h for 2.5 hours). Onset of infusion was time 0. At 30 minutes, lipopolysaccharide (LPS; 1 microg/kg, IV) was administered. Heart rate (HR), systolic arterial blood pressure (SAP), plasma tumor necrosis factor (TNF)-alpha activity, and a CBC were evaluated. RESULTS: Mean SAP was significantly reduced in dogs administered ketamine or saline solution at 2 and 2.5 hours, compared with values at time 0. However, there was no significant difference between treatments. At 1, 2, and 2.5 hours, dogs administered ketamine had a significantly lower HR than dogs administered saline solution. Although plasma TNF-alpha activity significantly increased, compared with values at time 0 for both groups, ketamine-treated dogs had significantly lower peak plasma TNF-alpha activity 1.5 hours after LPS administration. All dogs had significant leukopenia and neutropenia after LPS administration, with no differences detected between ketamine and saline solution treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of a subanesthetic dose of ketamine had immunomodulating effects in dogs with experimentally induced endotoxemia (namely, blunting of plasma TNF-alpha activity). However, it had little effect on hemodynamic stability and no effect on WBC counts.  相似文献   

14.
OBJECTIVE: To evaluate effects of preoperative administration of carprofen on renal function and hemostasis in dogs undergoing general anesthesia for fracture repair. ANIMALS: 26 client-owned dogs. PROCEDURE: Anesthesia was induced with levomethadone, diazepam, and propofol and maintained by administration of isoflurane in oxygen-nitrous oxide. Carprofen (4 mg/kg, SC) was administered 1 hour before induction to 13 dogs (group 1) and after extubation to the other 13 dogs (group 2). All dogs also received carprofen (4 mg/kg, SC, q 24 h) for the first 4 days after surgery. Renal function (glomerular filtration rate [GFR], urinary protein-to-urinary creatinine ratio [UP:UC], and results of urinalysis and biochemical analysis of plasma), hemostatic variables (bleeding time, platelet aggregation, prothrombin time [PT], activated partial thromboplastin time [APTT], and platelet count), and Hct were assessed before and at various time points after surgery. RESULTS: Analysis of results for renal function tests, most of the hemostatic and plasma biochemical variables, and Hct did not reveal significant differences between treatment groups. Values for GFR, UP:UC, PT, APTT, and platelet aggregation were outside reference ranges in many dogs before surgery and during the first 6 hours after surgery. In most dogs, these trauma-induced pathologic changes returned to within reference ranges during the 4-day period after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen did not cause clinically relevant adverse effects in dogs anesthetized for fracture repair after 5 days of treatment, even when it was administered before surgery or given to patients with trauma-induced alterations in renal function or hemostasis.  相似文献   

15.
In preliminary studies feeding the poorly absorbed carbohydrate sorbitol at 2.3 g/kg body weight as an indication of maximal fermentative capacity failed to produce the expected large increase in breath hydrogen excretion but did produce a transient diarrhea in five out of six control calves. Twelve healthy control and eighteen diarrheic calves were fed lactose or D-xylose on consecutive days at 1.15 g/kg body weight and a concentration of 46 g/L. Breath and blood samples were collected at 1 h intervals from 0 to 7 h. After administration of lactose, there was a significant increase in breath hydrogen excretion in diarrheic versus control calves. The increase in plasma glucose concentrations was delayed in diarrheic calves but the area under the absorption curve was similar in control and diarrheic calves. After administration of D-xylose, breath hydrogen excretion did not increase significantly but plasma D-xylose concentrations were significantly reduced in diarrheic calves. The pathogens commonly isolated from the feces were Cryptosporidium species, rotavirus and coronavirus. The number of pathogens and the severity of the calves' acid-base deficit were not related to the severity of carbohydrate malabsorption. Decreased absorption of lactose and D-xylose may be the result of intestinal villous atrophy caused by viral or parasite infection. It was concluded that carbohydrate malabsorption rather than a specific lactose maldigestion is a significant problem in diarrheic calves. Diarrheic calves appear to digest and absorb lactose when fed in small amounts.  相似文献   

16.
OBJECTIVE: To determine sedative and cardiorespiratory effects of i.m. administration of medetomidine alone and in combination with butorphanol or ketamine in dogs. DESIGN: Randomized, crossover study. ANIMALS: 6 healthy adult dogs. PROCEDURES: Dogs were given medetomidine alone (30 micrograms/kg [13.6 micrograms/lb] of body weight, i.m.), a combination of medetomidine (30 micrograms/kg, i.m.) and butorphanol (0.2 mg/kg [0.09 mg/lb], i.m.), or a combination of medetomidine (30 micrograms/kg, i.m.) and ketamine (3 mg/kg [1.36 mg/lb], i.m.). Treatments were administered in random order with a minimum of 1 week between treatments. Glycopyrrolate was given at the same time. Atipamezole (150 micrograms/kg [68 micrograms/lb], i.m.) was given 40 minutes after administration of medetomidine. RESULTS: All but 1 dog (given medetomidine alone) assumed lateral recumbency within 6 minutes after drug administration. Endotracheal intubation was significantly more difficult when dogs were given medetomidine alone than when given medetomidine and butorphanol. At all evaluation times, percentages of dogs with positive responses to tail clamping or to needle pricks in the cervical region, shoulder region, abdominal region, or hindquarters were not significantly different among drug treatments. The Paco2 was significantly higher and the arterial pH and Pao2 were significantly lower when dogs were given medetomidine and butorphanol or medetomidine and ketamine than when they were given medetomidine alone. Recovery quality following atipamezole administration was unsatisfactory in 1 dog when given medetomidine and ketamine. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a combination of medetomidine with butorphanol or ketamine resulted in more reliable and uniform sedation in dogs than did medetomidine alone.  相似文献   

17.
OBJECTIVE: To evaluate the pharmacokinetics of pentoxifylline (PTX) and its 5-hydroxyhexyl-metabolite, metabolite 1 (M1), in dogs after IV administration of a single dose and oral administration of multiple doses. ANIMALS: 7 sexually intact, female, mixed-breed dogs. PROCEDURE: A crossover study design was used so that each of the dogs received all treatments in random order. A drug-free period of 5 days was allowed between treatments. Treatments included IV administration of a single dose of PTX (15 mg/kg of body weight), oral administration of PTX with food at a dosage of 15 mg/kg (q 8 h) for 5 days, and oral administration of PTX without food at a dosage of 15 mg/kg (q 8 h) for 5 days. Blood samples were taken at 0.25, 0.5, 1, 1.5, 2, 2.5, and 3 hours after the first and last dose of PTX was administered PO, and at 5, 10, 20, 40, 80, and 160 minutes after PTX was administered IV. RESULTS: PTX was rapidly absorbed and eliminated after oral administration. Mean bioavailability after oral administration ranged from 15 to 32% among treatment groups and was not affected by the presence of food. Higher plasma PTX concentrations and apparent bioavailability were observed after oral administration of the first dose, compared with the last dose during the 5-day treatment regimens. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, oral administration of 15 mg of PTX/kg results in plasma concentrations similar to those produced by therapeutic doses in humans, and a three-times-a-day dosing regimen is the most appropriate.  相似文献   

18.
The effects of methadone and morphine were compared in conscious dogs. Six animals received morphine sulfate (1 mg/kg) or methadone hydrochloride (0.5 mg/kg [MET0.5] or 1.0 mg/kg [MET1.0]) intravenously (i.v.) in a randomized complete block design. Cardiopulmonary variables were recorded before (baseline), and for 120 min after drug administration. One outlier was not included in the statistical analysis for hemodynamic data. Morphine decreased heart rate (HR) compared to baseline from 30 to 120 min (?15% to ?26%), while cardiac index (CI) was reduced only at 120 min (?19%). Greater and more prolonged reductions in HR (?32% to ?46%) and in CI (?24% to ?52%) were observed after MET1.0, while intermediate reductions were recorded after MET0.5 (?19 to ?28% for HR and ?17% to ?27% for CI). The systemic vascular resistance index (SVRI) was increased after methadone; MET1.0 produced higher SVRI values than MET0.5 (maximum increases: 57% and 165% for MET0.5 and MET1.0, respectively). Compared to morphine, oxygen partial pressure (PaO2) was lower (?12% to ?13%) at 5 min of methadone (0.5 and 1.0 mg/kg), while carbon dioxide partial pressure (PaCO2) did not change significantly. It was concluded that methadone induces cardiovascular changes that are dose‐related and is a more potent cardiovascular depressant agent than morphine in conscious dogs.  相似文献   

19.
Effects of desmopressin acetate (1-desamino-8-D-arginine vasopressin [DDAVP]) on plasma von Willebrand factor (vWf) were studied in 12 purebred Doberman pinschers confirmed to have von Willebrand's disease (vWd) (plasma vWf antigen [vWf:Ag] concentrations, less than 30 U/dl). Twelve dogs had subnormal plasma botrocetin cofactor (BCf) activity and 11 dogs had prolonged buccal mucosa bleeding times. Tranquilization of three dogs with lenperone and three dogs with xylazine did not induce significant changes in mean plasma vWf:Ag concentrations or mean BCf activities. Thirty and 120 minutes after administration of DDAVP (1 micrograms/kg subcutaneously), there was significant shortening of the mean buccal mucosa bleeding time. Ten dogs responded to DDAVP with increases in BCf activity which exceeded 10 U/dl at 30 or 120 minutes, or both, after the drug was administered. At the same time, increases in plasma vWf:Ag concentrations were smaller than the increases in BCf activity. It was shown by multimeric analysis that primarily the higher molecular weight forms of vWf increased in plasma in response to DDAVP.  相似文献   

20.
1. Four experiments were conducted using the highly specific mu and delta opioid receptor agonists morphiceptin (B-casomorphin 1-4, amide) or [Met5]-enkephalin, respectively, to evaluate the effect of mu and delta opioid receptor agonists on ingestive behaviour in the domestic fowl. 2. Intracerebroventricular (ICV) administration of 0.625, 1.25, 2.5 and 5.0 micrograms of morphiceptin significantly stimulated drinking, while having no effect on feeding. Intramuscular injection of 0.5, 1.5 and 3.0 mg morphiceptin/kg body weight induced a significant increase in feeding, whereas drinking was not altered. 3. ICV administration of 0.625, 1.25, 2.5 and 5.0 micrograms [Met5]-enkephalin, as well as intramuscular injection of 0.5, 1.5 and 3.0 mg [Met5]-enkephalin significantly stimulated feeding while having no effect on drinking. 4. These results suggest that, in the central nervous system, mu opioid receptor agonists stimulate drinking and delta receptor agonists stimulate feeding. At sites outside the blood-brain barrier, both mu and delta opioid receptor agonists stimulate feeding.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号