Repeatability of a telephone questionnaire on cat-ownership patterns and pet-owner demographics evaluation in a community in Texas, USA.

The repeatability of a telephone questionnaire on cat-ownership patterns, demographics and attitudes towards homeless cats in a community was evaluated. Randomly selected households (n=100) within Caldwell, Texas, were included in the study. The response percentage was 84% (100/119) among those contacted and 75% (100/134) among all eligible respondents. Repeatability was measured by administering the same survey twice to the first 100 responding subjects, with an average (range) of 48 (25-64) days between interviews. The survey was initially administered from 6 June to 28 June 2005 and the follow-up survey was administered from 19 July to 11 August 2005. Repeatability for most cat-ownership characteristics was fair to good between the two interviews (kappa 0.47-0.82). Knowledge of companion animals and subject attachment to pet questions had good correlations between the two interviews (rsp 0.52 and 0.60, respectively). Subject-demographic questions had excellent repeatability (kappa 0.66-1.00).

Isolation and characterization of Thermus bacteriophages.

One-hundred-fifteen bacteriophage strains were isolated from alkaline hot springs in Iceland, New Zealand, Russia (Kamchatka), and the U.S.A. The phages belonged to the Myoviridae, Siphoviridae, Tectiviridae, and Inoviridae families. Over 50% of isolates were isometric or filamentous. One type of siphovirus had giant tails of over 800 nm in length. Phages were further characterized by host range, genome size, DNA restriction endonuclease digestion patterns, and temperature and pH sensitivity. Myoviruses and tectiviruses had a worldwide distribution. Most phages were narrowly host-specific and all were highly resistant against heating and alkaline and acidic pH. This is the first time that tectiviruses and filamentous phages are reported for bacteria of the Thermus-Deinococcus phylum. The presence of tectiviruses, inoviruses, and myoviruses is attributed to acquisition from ancestral gamma-proteobacteria by horizontal gene transfer.

Diet and lifestyle variables as risk factors for chronic renal failure in pet cats.

A case-control study examining diet and lifestyle variables to generate hypotheses of potential risk factors for chronic renal failure in pet cats was conducted in five private practices in Texas, USA and at the Texas A&M University Veterinary Medical Teaching Hospital. A telephone questionnaire was used to gather information from owners of 38 cats newly diagnosed with CRF between December 1994 and 1995 and from owners of 56 control cats. Factor analysis was used to determine whether composite variables should be constructed to summarize the nutritional predictors adequately. The composite variables and other lifestyle variables were analyzed with logistic-regression. Three final exploratory models were developed: ad libitum feeding with fiber; ad libitum with Factor-2 (a composite variable composed of fiber, magnesium, protein, sodium and ash); and fiber alone. Ad libitum feeding and increased ash intake were associated with increased odds of CRF; increased dietary fiber, magnesium, protein and sodium were associated with decreased odds of CRF.

Repeatability and prediction from a telephone questionnaire measuring diet and activity level in cats.

A telephone questionnaire was developed to collect information on diet, activity level, and health as part of a prior study examining long-term outcome of early-age vs. traditional-age gonadectomy in cats. The objectives of our current study were to measure the repeatability of the questionnaire through time, to describe changes in diet and activity level over a period of 1-2 years, and to determine whether current diet and activity level characteristics might influence owner ability to recall past information.A total of 100 previously interviewed cat owners completed the second administration of the telephone questionnaire. The interval between the first and second administration of the questionnaire ranged from 0.5 to 2.6 years (median=1.5 years). Owners answered multiple-choice questions related to activity level, appetite, body condition, diet type and brand (open-ended), frequency of feeding, indoor/outdoor status, and time spent outdoors. All variables measured in the questionnaire were analyzed using kappa and a 95% confidence interval. Agreement between the original and current interviews was poor for questions referring to activity level, appetite, body condition, type and brand of treats fed, and table scraps. Agreement was moderate for questions referring to brand of dry and canned foods fed, frequency of feeding, and time spent outdoors. Agreement was high for questions referring to whether dry and canned foods were fed and indoor/outdoor status. Change over time as assessed by kappa was moderate-to-high for all variables measured with the exception of whether dry diet was fed and indoor/outdoor status. Recall of all variables that changed appeared to be at least moderately influenced by current characteristics.

The protein capsid of filamentous bacteriophage PH75 from Thermus thermophilus.

The PH75 strain of filamentous bacteriophage (Inovirus) grows in the thermophilic bacterium Thermus thermophilus at 70 degrees C. We have characterized the viral DNA and determined the amino acid sequence of the major coat protein, p8. The p8 protein is synthesized without a leader sequence, like that of bacteriophage Pf3 but unlike that of bacteriophage Pf1, both of which grow in the mesophile Pseudomonas aeruginosa. X-ray diffraction patterns from ordered fibres of the PH75 virion are similar to those from bacteriophages Pf1 and Pf3, indicating that the protein capsid of the PH75 virion has the same helix symmetry and subunit shape, even though the primary structures of the major coat proteins are quite different and the virions assemble at very different temperatures. We have used this information to build a molecular model of the PH75 protein capsid based on that of Pf1, and refined the model by simulated annealing, using fibre diffraction data extending to 2.4 A resolution in the meridional direction and to 3.1 A resolution in the equatorial direction. The common design may reflect a fundamental motif of alpha-helix packing, although differences exist in the DNA packaging and in the means of insertion of the major coat protein of these filamentous bacteriophages into the membrane of the host bacterial cell. These may reflect differences in the assembly mechanisms of the virions.

The role of veterinary epidemiology in the study of free-roaming dogs and cats.

Free-roaming dogs or cats are domestic dogs and cats that are not confined to a yard or house. Free-roaming dogs and cats have long caused major public-health problems and animal-welfare concerns in many countries. Free-roaming dogs have been considered to be more of a problem than cats for several reasons, but the literature addressing dogs focuses primarily on their role in rabies spread and control. Free-roaming cats are becoming more of an issue in countries where free-roaming dog problems are coming under control. The change in perception of pets, beyond their value as a commodity, has also contributed to the increase in concern and attention focused on free-roaming dogs and cats. Epidemiologists have contributed much to these studies of these populations and have potential to contribute even more. The epidemiologic methods and approaches, the experience of epidemiologists in interdisciplinary teams and the importance of considering the separate sub-populations in study design and analysis all are critical in designing and evaluating interventions for free-roaming dogs and cats. In this paper, I will (1) describe a set of useful definitions regarding free-roaming dogs and cats, (2) summarize past and present topics of study in free-roaming dogs and cats, using selected examples, (3) describe the limitations of existing work and how epidemiologists might strengthen and improve this work, and (4) outline areas needing more attention by epidemiologists and why these are important.

Long-term health and predictors of survival for hyperthyroid cats treated with iodine 131.

Two hundred thirty-one cats treated with radioactive iodine at the Texas Veterinary Medical Teaching Hospital were followed for a median of 25 months by means of an ambidirectional (prospective, retrospective) cohort study design. Cox proportional hazards models were used to determine predictors of survival based on data at the time of hyperthyroid diagnosis (collected retrospectively) and found that only age at diagnosis and sex of the cat were predictors of survival. Increasing age (for each year of age, relative risk [RR] = 1.2, 95% confidence interval [CI] = 1.1-1.3) and being male (RR = 0.68, 95% CI = 0.5-0.9) increased likelihood of death. Tables predicting survival after diagnosis and treatment of hyperthyroidism for various age and sex combinations were created. In addition, Cox proportional hazard models were run with all data available at the end of the study (collected retrospectively and prospectively) including number and type of major health problems reported at the time of death or censoring. In this model, significant factors were age at diagnosis, sex, and either type of major health problem or number of health problems. Cats with renal disease or cancer were more likely not to survive and increasing from none to 2 health problems also decreased survival. Renal problems and cancer were the most common health problems at the time of death or censoring. This study provides estimates of duration of survival for cats successfully treated for hyperthyroidism with radioactive iodine, which can be useful in assisting with client treatment decisions.

Long-term outcome of gonadectomy performed at an early age or traditional age in dogs.

OBJECTIVE: To determine long-term results and complications of gonadectomy performed at an early age (prepubertal) or at the traditional age in dogs. DESIGN: Cohort study. ANIMALS: 269 dogs from animal shelters. PROCEDURE: Dogs that underwent gonadectomy were allotted to 2 groups on the basis of estimated age at surgery (traditional age, > or =24 weeks old; prepubertal, < 24 weeks old). Adoptive owner information was obtained from shelter records, and telephone interviews were conducted with owners to determine physical or behavioral problems observed in the dogs since adoption. Follow-up information was obtained from attending veterinarians for dogs with complex problems or when owners were uncertain regarding the exact nature of their dog's problem. RESULTS: Prepubertal gonadectomy did not result in an increased incidence of behavioral problems or problems associated with any body system, compared with traditional-age gonadectomy, during a median follow-up period of 48 months after gonadectomy. Rate of retention in the original adoptive household was the same for dogs that underwent prepubertal gonadectomy as those that underwent traditional-age gonadectomy. Infectious diseases, however, were more common in dogs that underwent prepubertal gonadectomy. CONCLUSIONS AND CLINICAL IMPLICATIONS: With the exception of infectious diseases, prepubertal gonadectomy may be safely performed in dogs without concern for increased incidence of physical or behavioral problems during at least a 4-year period after gonadectomy.

The effects of thyroid hormones on the skin of beagle dogs.

The effects of hypothyroidism on canine skin were determined by comparing morphologic, morphometric, and hair cycle differences in skin biopsy samples from 3 groups of age- and gender-matched Beagle dogs: (1) euthyroid dogs; (2) dogs made hypothyroid by administration of 131I; and (3) dogs made hypothyroid and maintained in a euthyroid state by treatment with synthetic thyroxine. After 10 months of observation, there was slower regrowth of hair 2 months after clipping in the untreated-hypothyroid dogs. Untreated-hypothyroid dogs had a greater number of follicles in telogen and fewer hair shafts (ie, a greater number of hairless telogen follicles) than did the control group. The control dogs had a greater number of telogen follicles but the same number of hair shafts as the treated-hypothyroid group. Treated-hypothyroid dogs had the greatest number of follicles in the growing stage of the hair cycle (anagen). This study suggests that, at least in Beagles, induced hypothyroidism does not affect the pelage as dramatically as has been described in naturally occurring disease. This is because normal Beagles retain hair shafts in follicles for long periods, and the alopecia of hypothyroidism appears to evolve slowly because of the prolongation of this haired telogen stage. The evaluation of thyroxine-treated hypothyroid dogs demonstrates that thyroid hormone supplementation of Beagle dogs with induced hypothyroidism stimulates hair growth.

Long-term outcome of gonadectomy performed at an early age or traditional age in cats.

OBJECTIVE: To determine long-term results and complications of gonadectomy performed at an early age (prepubertal) or at the traditional age in cats. DESIGN: Cohort study. ANIMALS: 263 cats from animal shelters. PROCEDURE: Cats that underwent gonadectomy were allotted to 2 groups on the basis of estimated age at surgery (traditional age, > or = 24 weeks old; prepubertal, < 24 weeks old). Adoptive owner information was obtained from shelter records, and telephone interviews were conducted with owners to determine physical or behavioral problems observed in the cats after adoption. Follow-up information was obtained from attending veterinarians for cats with complex problems or when owners were uncertain regarding the exact nature of their cat's problem. RESULTS: Compared with traditional-age gonadectomy, prepubertal gonadectomy did not result in an increased incidence of infectious disease, behavioral problems, or problems associated with any body system during a median follow-up period of 37 months. Additionally, the rate of retention in the original adoptive household was the same for cats that underwent prepubertal gonadectomy as those that underwent traditional-age gonadectomy. CONCLUSIONS AND CLINICAL RELEVANCE: Prepubertal gonadectomy may be performed safely in cats without concern for increased incidence of physical or behavioral problems for at least a 3-year period after gonadectomy.

Arterial blood pressure measurement in a population of healthy geriatric dogs.

The purpose of this study was to evaluate healthy geriatric dogs for the presence of systemic hypertension. Thirty-three geriatric dogs (i.e., dogs exceeding the geriatric age range for their weight group) and 22 control dogs (i.e., dogs less than six years of age) were evaluated by measuring blood pressure with an oscillometric monitor. Five consecutive blood pressure measurements were taken in each dog, averaged, and compared. Diastolic and mean blood pressure measurements were significantly lower in the geriatric group as compared to the control group. Systolic blood pressure measurements were not significantly different between the two groups. Systemic hypertension does not appear to be a common clinical problem in the healthy geriatric dog.

Nitric oxide generation in a rat model of acute portal hypertension.

OBJECTIVE: To document blood nitric oxide concentrations in the portal vein and systemic circulation in a rat model of acute portal hypertension and compare values with a control group and a sham surgical group. ANIMALS: 30 rats; 10 controls (group 1), 10 sham surgical (group 2), and 10 rats with surgically induced acute portal hypertension (group 3). PROCEDURE: Following induction of anesthesia, catheters were placed surgically in the carotid artery, jugular, and portal veins of group 2 and 3 rats and in the carotid artery and jugular vein of group 1 rats. Baseline heart and respiratory rates, rectal temperature, and vascular pressure measurements were obtained, and blood was drawn from all catheters for baseline nitric oxide (NO) concentrations. Acute portal hypertension was induced in the group 3 rats by tying a partially occluding suture around the portal vein and a 22-gauge catheter. The catheter was then removed, resulting in a repeatable degree of portal vein impingement. After catheter placement, all variables were remeasured at 15-minute intervals for 3 hours. RESULTS: Blood nitric oxide concentrations were greater in all vessels tested in group 3 than in group 2 rats. CONCLUSIONS AND CLINICAL RELEVANCE: Acute portal hypertension in this experimental model results in increased concentrations of NO in the systemic and portal circulation. On the basis of information in the rat, it is possible that increased NO concentrations may develop in dogs following surgical treatment of congenital portosystemic shunts if acute life-threatening portal hypertension develops. Increased NO concentrations may contribute to the shock syndrome that develops in these dogs.

Contrast radiographic findings in canine bacterial discospondylitis: a multicenter, retrospective study of 27 cases.

A multicenter, retrospective study was undertaken to evaluate contrast radiographic findings in canine bacterial discospondylitis. Records and myelograms or epidurograms of 27 patients were obtained from five colleges of veterinary medicine. Fifteen cases (56%) were evaluated as having some degree of spinal cord compression. The majority (73.3%) of the cases had only soft tissue as the compressive mass. The median compression for all cases was 5% of the vertebral canal. No difference was noted for compression based on anatomical site (i.e., cervical versus thoracolumbar versus lumbosacral). No significant correlation between degree of lesion compression and clinical outcome was noted, but there was a trend toward increased mortality with greater compression. There was no correlation between the ambulatory status and the ultimate outcome. Three of the 15 (20%) cases showed vertebral subluxation. Results of this study indicate that static spinal cord compression is not a significant component of the neurological dysfunction associated with bacterial discospondylitis. Identification of vertebral subluxation in some patients may indicate a dynamic lesion that should be evaluated with stress radiography.

The efficacy of mechanical abrasion and talc slurry as methods of pleurodesis in normal dogs.

OBJECTIVE: To determine the efficacy of mechanical abrasion and talc slurry as methods for pleurodesis in normal dogs. STUDY DESIGN: Experimental study. ANIMALS OR SAMPLE POPULATION: Ten normal beagle dogs. METHODS: Group I dogs had mechanical abrasion (MA) of the pulmonary and costal pleurae performed in one hemithorax with a dry gauze sponge with a median sternotomy approach. Group II dogs had 100 mL of a 1 g talc slurry (TS) administered into one hemithorax through a tube thoracostomy. Administration of the TS was visualized by using video thoracoscopy. All dogs were evaluated at 2, 10, 20, and 30 days postoperatively by means of thoracic radiography and ultrasonographic thoracic wall measurement. The dogs were euthanatized 30 days postoperatively and a gross necropsy was performed. Hemithoraces were assigned a pleurodesis score (0-4) and an obliteration grade (0-6). Tissues were collected for histopathologic examination of pulmonary pleura, costal pleura, and pleural adhesions. Pulmonary and costal pleurae were graded for the degree of fibrosis (0-4). RESULTS: Obliteration grade and costal pleural fibrosis score were significantly higher for the treated sides in the MA dogs compared with the TS dogs. MA Dogs: Mechanical abrasion dogs had pleurodesis, obliteration, and pleural fibrosis scores that were greater on the treated side than the untreated side, however, the differences were not statistically significant. Only two MA dogs had firm adhesion of the pulmonary pleura to the costal pleura in portions of the cranial and middle lung lobes in the treated hemithorax. Thoracic wall surface area covered with adhesions was 15% and 21% in each of these two dogs. The median pulmonary pleural fibrosis score of all MA dogs for the treated hemithorax was 3 compared to 0 on the untreated side. TS Dogs: There was no statistical difference for pleurodesis scores and obliteration grades between the treated and untreated sides. No dogs showed evidence of pulmonary to costal pleural adhesions. Histopathology showed talc crossover into the untreated side in all five dogs. Median pulmonary fibrosis score of the treated hemithorax was 1 compared with 0 on the untreated side. CONCLUSIONS: Neither method of pleurodesis produced sufficient pleural adhesions to obliterate the pleural space. It is possible that the degree of pulmonary pleural fibrosis present in MA dogs may be sufficient to limit air leakage from pulmonary blebs and bullae resulting in successful treatment of spontaneous pneumothorax.

Results of a survey of small-animal practitioners on the perceived clinical efficacy and safety of an oral nutraceutical.

A mail survey of 3080 practitioners from two sampling frames was used to determine the perceived clinical efficacy and safety of an oral nutraceutical for the treatment of degenerative joint disease (DJD) in small animals. Overall response rate was 82%, of which 64% reported that they were recommending the oral nutraceutical to their clients. There was a high variability reported between the severity of DJD and response to treatment. Sixty-eight percent of practitioners reported lame dogs older than five years to be the most responsive to treatment. Most practitioners (83%) believed response to treatment with the studied product occurred within four weeks. Practitioners using the product rated the clinical efficacy of the product to be either 'good' or 'excellent' in improving mobility, alleviating pain and improving attitude in the majority of the treated animals. No practitioner reported a worsening of pain, mobility or attitude. Self-reported adverse effects were 2% (the most common was gastrointestinal upset). The results of this survey indicated that perceived clinical efficacy of the studied nutraceutical in the treatment of DJD was regarded to be 'good' or 'excellent' by most of the practitioners who use this product and was considered to be safe with minimal side effects. This provides additional information on the product for use in planning future clinical trials.

Evaluation of analgesia provided by postoperative administration of butorphanol to cats undergoing onychectomy.

OBJECTIVE: To evaluate adequacy of analgesia provided by postoperative administration of butorphanol to cats undergoing onychectomy. DESIGN: Randomized controlled trial. ANIMALS: 63 cats undergoing elective onychectomy. PROCEDURE: Cats were randomly assigned to a treatment (n = 42) or control group (21). Cats in the treatment group were given butorphanol parenterally immediately and 4 hours after surgery and orally for 2 days after surgery. Rectal temperature, heart rate, and respiratory rate were recorded and scores were assigned for temperament, recovery, sedation, analgesia, and lameness for the first 24 hours after surgery. Owners provided scores for appetite, personality, and lameness the first and second days after discharge from the hospital. RESULTS: Heart rate, respiratory rate, rectal temperature, and temperament and sedation scores were not significantly different between groups at any evaluation time. Recovery scores were significantly better for butorphanol-treated than for control-group cats 10 minutes after extubation. Analgesia scores were significantly better for butorphanol-treated than for control-group cats between 5 and 24 hours after surgery. Fewer butorphanol-treated than control-group cats were lame at the time of discharge from the hospital. The first day after discharge, owners reported that percentages of butorphanol-treated cats that ate normally, acted normally, and had only mild or no lameness were significantly higher than percentages of control-group cats that did. Significant differences between groups were not detected the second day after discharge. CLINICAL IMPLICATIONS: Results suggest that for cats undergoing onychectomy, administration of butorphanol the day of surgery and the first full day after surgery provides effective analgesia and improves recovery, appetite, and gait.

Detomidine-butorphanol-propofol for carotid artery translocation and castration or ovariectomy in goats.

OBJECTIVE: To determine the safety and efficacy of propofol, after detomidine-butorphanol premedication, for induction and anesthetic maintenance for carotid artery translocation and castration or ovariectomy in goats. STUDY DESIGN: Case series. ANIMALS: Nine 4-month-old Spanish goats (17.1 +/- 2.6 kg) were used to evaluate propofol anesthesia for carotid artery translocation and castration or ovariectomy. METHODS: Goats were premedicated with detomidine (10 micrograms/kg intramuscularly [i.m.]) and butorphanol (0.1 mg/kg i.m.) and induced with an initial bolus of propofol (3 to 4 mg/kg intravenously [i.v.]). If necessary for intubation, additional propofol was given in 5-mg (i.v.) increments. Propofol infusion (0.3 mg/kg/min i.v.) was used to maintain anesthesia, and oxygen was insufflated (5 L/min). The infusion rate was adjusted to maintain an acceptable anesthetic plane as determined by movement, muscle relaxation, ocular signs, response to surgery, and cardiopulmonary responses. Systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures, heart rate (HR), ECG, respiratory rate (RR), SpO2, and rectal temperature (T) were recorded every 5 minutes postinduction; arterial blood gas samples were collected every 15 minutes. Normally distributed data are represented as mean +/- SD; other data are medians (range). RESULTS: Propofol (4.3 +/- 0.9 mg/kg/min i.v.) produced smooth, rapid (15.2 +/- 6 sec) sternal recumbency. Propofol infusion (0.52 +/- 0.11 mg/kg/min i.v.) maintained anesthesia. Mean anesthesia time was 83 +/- 15 minutes. Muscle relaxation was good; eye signs indicated surgical anesthesia; two goats moved before surgery began; one goat moved twice during laparotomy. Means are reported over the course of the data collection period. Means during the anesthesia for pHa (arterial PH), PaCO2, PaO2, HCO3-, and BE (base excess) ranged from 7.233 +/- 0.067 to 7.319 +/- 0.026, 54.1 +/- 4.6 to 65.3 +/- 12.0 mm Hg, 133.1 +/- 45.4 to 183.8 +/- 75.1 mm Hg, 26.9 +/- 2.6 to 28.2 +/- 2.1 mEq/L, and -0.8 +/- 2.9 to 1.4 +/- 2.2 mEq/L. Means over time for MAP were 53 +/- 12 to 85 +/- 21 mm Hg. Mean HR varied over time from 81 +/- 6 to 91 +/- 11 beats/minute; mean RR, from 9 +/- 8 to 15 +/- 5 breaths/minute; SpO2 from 97 +/- 3% to 98 +/- 3%; mean T, from 36.0 +/- 0.6 degrees C to 39.1 +/- 0.7 degrees C. Over time, SpO2 and SaO2 did not change significantly; HR, RR, T, and PaCO2 decreased significantly; SAP, DAP, MAP, pHa, PaO2, and BE increased significantly. HCO3- concentrations increased significantly, peaking at 45 minutes. Recoveries were smooth and rapid; the time from the end of propofol infusion to extubation was 7.3 +/- 3 minutes, to sternal was 9.2 +/- 5 minutes, and to standing was 17.7 +/- 4 minutes. Median number of attempts to stand was two (range of one to four). Postoperative pain was mild to moderate. CONCLUSIONS: Detomidine-butorphanol-propofol provided good anesthesia for carotid artery translocation and neutering in goats. CLINICAL RELEVANCE: Detomidine-butorphanol-propofol anesthesia with oxygen insufflation may be safely used for surgical intervention in healthy goats.

Cardiovascular effects of buprenorphine in anesthetized dogs.

OBJECTIVE: To determine the cardiovascular effects of buprenorphine in isoflurane- and halothane-anesthetized dogs. ANIMALS: 6 healthy adult hound-type dogs given buprenorphine (16 micrograms/kg of body weight, i.v.) or isovolumetric 5% dextrose solution during anesthesia with isoflurane or halothane. PROCEDURE: Each dog was anesthetized 4 times, with a minimum of 10 days between episodes. Anesthesia was induced with isoflurane or halothane in O2 by mask, and was maintained with 1.9% isoflurane or 1.3% halothane (end-tidal concentration). The PaCO2 was maintained between 35 and 45 mm of Hg by use of mechanical ventilation, and the following variables were determined: systolic, diastolic, and mean arterial blood pressures; cardiac output; cardiac index; stroke volume; heart rate; systemic vascular resistance; mean pulmonary arterial pressure; and pulmonary vascular resistance. In addition, arterial blood samples for gas and acid-base analyses were collected at 30-minute intervals for 2.5 hours. After baseline values were recorded, dogs were randomly assigned to receive either buprenorphine (16 micrograms/kg, i.v.) or isovolumetric 5% dextrose solution. All variables were then recorded at 15-minute intervals for 2.5 hours. RESULTS: During isoflurane anesthesia, buprenorphine administration caused significant (P < or = 0.05) reductions in diastolic arterial pressure, mean arterial pressure, systolic arterial pressure, cardiac index, and heart rate, whereas systemic vascular resistance increased significantly. During halothane anesthesia, buprenorphine administration caused significant decreases in heart rate, cardiac index, mean, systolic and diastolic arterial blood pressures, and stroke volume, whereas pulmonary arterial blood pressure and systemic vascular resistance increased significantly. CONCLUSION: Although the changes seen were significant, they were not sufficiently large to be of clinical importance in healthy dogs.