Effects of finasteride on size of the prostate gland and semen quality in dogs with benign prostatic hypertrophy

OBJECTIVE: To determine the effect of the 5alpha-reductase inhibitor finasteride on prostatic diameter and volume, semen quality, and serum dihydrotestosterone (DHT) and testosterone concentrations in dogs with spontaneous benign prostatic hypertrophy (BPH). DESIGN: Double-blind placebo-controlled trial. ANIMALS: 9 dogs with BPH. PROCEDURE: Five dogs were treated with finasteride for 16 weeks (0.1 to 0.5 mg/kg [0.05 to 0.23 mg/lb] of body weight, PO, q 24 h); the other 4 received a placebo. Prostatic diameter, measured radiographically, prostatic volume, measured ultrasonographically, semen quality, and serum DHT and testosterone concentrations were evaluated before and during treatment. After receiving the placebo for 16 weeks, the 4 control dogs were treated with finasteride for 16 weeks, and evaluations were repeated. RESULTS: Finasteride significantly decreased prostatic diameter (mean percentage decrease, 20%), prostatic volume (mean percentage decrease, 43%), and serum DHT concentration (mean percentage decrease, 58%). Finasteride decreased semen volume but did not adversely effect semen quality or serum testosterone concentration. No adverse effects were reported by owners of dogs in the study. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that finasteride can be used to reduce prostatic size in dogs with BPH without adversely affecting semen quality or serum testosterone concentration.     

Evaluation of techniques for diagnosis of canine prostatic diseases

Bacterial culture and cytology of semen, bacterial culture and cytology of prostatic fluid washings, urinalysis, bacterial culture of urine, and blood leukocyte counts were performed on specimens from dogs with prostatic hyperplasia, chronic prostatitis, or prostatic neoplasia. Hemorrhage was the most frequent abnormal finding in semen from dogs with prostatic hyperplasia. Inflammation was the most frequent abnormal finding in dogs with chronic prostatitis. Bacterial culture of semen was sensitive but not specific for chronic bacterial prostatitis, due to false-positive results from urethral contamination. Hemorrhage was the most frequent abnormal finding in prostatic fluid washings from dogs with prostatic hyperplasia. Inflammation was the most frequent abnormal finding in dogs with chronic prostatitis. Abnormal epithelial cells were found after prostatic massage in 4 dogs with neoplasia, although these cells were difficult to identify as neoplastic. Prostatic fluid washings were not useful for detecting chronic bacterial prostatitis, due to an inability to detect increases in bacterial counts in the fluid when urine bacterial counts were high. Hematuria was the predominant abnormal finding in urinalysis from dogs with hyperplasia and neoplasia. Pyuria was the most frequent abnormal finding in dogs with chronic prostatitis. Urine was usually culture-positive when there was prostatic infection. Blood leukocyte counts were normal in dogs with prostatic hyperplasia and usually normal in dogs with neoplasia. Leukocytosis, a left shift, and toxic white blood cells were predictive of abscessation, although the blood leukocyte count was not a very sensitive indicator for infection without abscessation.     

Age-related changes in the prostate and testes of the beagle dog.

Age-related changes in the histologic morphology of the Beagle dog prostate have been used as a model for similar changes that occur in human beings. Previous studies of the aging changes in Beagle dogs have been limited to animals less than 10 years of age. In this study, the prostate, testes, and serum testosterone levels were evaluated in healthy Beagle dogs that were grouped by age to provide five groups of dogs that ranged from 3 to 14 years of age. Tissue sections from the prostate and testes were examined qualitatively and quantitatively by light microscopy. All animals 6 years of age and older had histologic characteristics of complex benign prostatic hyperplasia. A mean statistically significant increase in prostatic weight with increased age was noted (mean value 1.08 +/- 0.22 g/kg body weight at 3 years of age, increasing to 2.64 +/- 0.37 g/kg body weight at 14 years of age). Morphometric analysis of the prostatic tissue suggested that similar to the change observed in human males, the increase in size was primarily due to an increase in the absolute volume of interstitial tissues (mean value 2.8 +/- 1.1 cm3 at 3 years of age, increasing to 7.4 +/- 1.3 cm3 at 14 years of age). The epithelial component did not contribute to the increase noted, with the exception that the percentage of glandular lumen did increase with age, indicating progressive cystic dilatation of the glands.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum testosterone,sperm quality,cytological, physicochemical and biochemical characteristics of the prostatic fraction of dogs with prostatomegaly

Prostatomegaly is a common finding in older non‐neutered dogs. This study compared the serum testosterone, sperm quality and characteristics of the prostatic fraction between healthy dogs and dogs with prostatomegaly. Blood samples of ten dogs (five dogs from each group) were taken for serum testosterone measurement. Sperm motility, vigour, concentration, viability, membrane functionality and morphology were analysed in sperm‐rich fraction. Osmolality, pH, cell types, and albumin, haemoglobin, acid phosphatase, alkaline phosphatase, glucose, triglycerides, cholesterol, calcium, phosphorus, magnesium and chloride were analysed in prostatic fraction. Dogs with prostatomegaly have the lowest sperm motility, vigour, concentration and functional membrane. Dogs with prostatomegaly have the highest glucose, triglycerides and cholesterol. Glucose was the only constituent positively correlated with serum testosterone and prostate volume. It can be concluded that dogs with prostatomegaly have poorer sperm quality, and glucose, triglycerides and cholesterol in prostatic fraction can be used as prostatomegaly biomarkers.     

Relationship of seminal volume to size and disease of the prostate in the beagle.

The seminal volume of young adult Beagles was correlated with the size of and disease in their prostates. The ejaculate volume of naturally collected semen increased in a linear manner with prostatic weight in dogs with normal or glandular hyperplastic prostates. This correlation was not observed in the dogs with cystic hyperplasia, in which there was a reduction in volume of 50% in the semen produced for each gram of prostate. There were no significant differences in other seminal characteristics regardless of prostatic size of disease.     

Serum concentrations of acute-phase proteins in dogs with leishmaniosis during short-term treatment

OBJECTIVE: To evaluate changes in serum concentrations of acute-phase proteins in dogs with leishmaniosis during short-term therapy in accordance with 2 treatment protocols and determine whether concentrations of acute-phase proteins could be used to monitor the initial response of dogs to treatment. ANIMALS: 12 dogs naturally infected with Leishmania infantum. PROCEDURE: Dogs were allocated into 2 groups. Dogs of group 1 were treated by use of meglumine antimonate (100 mg/kg, SC, q 24 h) administered concurrently with allopurinol (15 mg/kg, PO, q 12 h) for 20 days and then with allopurinol alone at the same dosage for the subsequent 30 days. Dogs of group 2 were treated by administration of allopurinol alone (15 mg/kg, PO, q 12 h) for 60 days). Blood samples were obtained before and during treatment for measurement of serum concentrations of acute-phase proteins and determination of CBC counts, serum biochemical analyses, and electropherograms. RESULTS: All dogs evaluated in the study had increased concentrations of C-reactive protein, haptoglobin, and ceruloplasmin at the time of diagnosis of leishmaniosis. Mean concentration of serum amyloid A before treatment was also increased, but some of the dogs had concentrations of serum amyloid A that were within the reference range. Concentrations of C-reactive protein and ceruloplasmin decreased significantly in all dogs at the end of the study period. CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of concentrations of selected acute-phase proteins, such as C-reactive protein or ceruloplasmin, could be used to evaluate the initial response of dogs with leishmaniosis to treatment.     

Comparison of glomerular filtration rate between greyhounds and non-Greyhound dogs

Greyhounds have significantly higher serum creatinine (SCr) concentration than do non-Greyhound dogs that may be attributable to differences in glomerular filtration rate (GFR). By means of plasma clearance of technetium Tc 99m diethylenetriaminepentaacetic acid, GFR was measured in 10 Greyhounds and 10 non-Greyhound dogs with normal findings of physical examination, CBC, serum biochemical analysis, and urinalysis. Dogs were fed the same diet for a minimum of 6 weeks before GFR data collection. Greyhounds had significantly higher mean +/- SD GFR (3.0 +/- 0.1 vs 2.5 +/- 0.2 ml/min/ kg; P = .01) and SCr concentration (1.8 +/- 0.1 vs 1.5 +/- 0.1 mg/dL; P = .03) than did non-Greyhound dogs, but the serum urea nitrogen (SUN) concentration was not significantly different (18 +/- 1 vs 18 +/- 2 mg/dL; P = .8). Therefore, the higher SCr concentration in Greyhounds is not attributable to decreased GFR, and may be associated with the high muscle mass in the breed. Healthy Greyhounds have higher GFR than do non-Greyhound dogs.     

Clinical management of the subfertile stud dog.

Many subfertile stud dogs can sire pups with appropriate management. Determination of the area of the problem (libido, ability to breed, semen quality) is the first step. Each of these areas can often be improved or managed. A complete history, physical examination, and semen evaluation should be performed on every patient. In specific cases, additional diagnostics may be helpful, including a CBC, biochemistry profile, urinalysis, semen cultures, ultrasonography, and biopsy. Management of breeding, including ovulation timing and intrauterine insemination, can be vital in dogs with low spermatozoal numbers or motility. Treatment of underlying prostatic disease can dramatically improve semen quality and fertility.     

Radiographic, biomechanical, and pathologic effects of hemoglobin glutamer-200 in dogs undergoing cemented total hip arthroplasty

OBJECTIVE: To determine whether use of hemoglobin glutamer-200 (bovine) as a partial blood volume replacement in dogs undergoing cemented total hip replacement caused any deleterious effects on the bone-cement or cement-prosthesis interface, exerted any deleterious effects on body organs, or caused any complications during the anesthetic, immediate recovery, or long-term recovery period. ANIMALS: 9 adult dogs. METHODS: Dogs were anesthetized, and 15% of the blood volume was removed. Simultaneously, lactated Ringer's solution was infused, and 6 dogs were given hemoglobin glutamer (1 g/kg of body weight, IV). Unilateral total hip replacement was performed. Limb use was assessed visually, and force-plate and radiographic evaluations were performed before, and 8 weeks after, surgery. Eight weeks after surgery, dogs were euthanatized, necropsies were performed, and prosthetic component pullout forces were determined. RESULTS: There were no significant differences between treated and control dogs in regard to biomechanical (visual assessment of gait, force-plate analysis, femoral and acetabular component pullout forces) and pathologic evaluations (physical examination, CBC, serum biochemical analyses, necropsy, and histologic evaluations). Radiographic signs of loosening of the femoral component were seen in 4 dogs treated with hemoglobin glutamer. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of hemoglobin glutamer as a blood substitute did not appear to have any deleterious effects in dogs undergoing total hip arthroplasty. The radiographic findings, which were discordant with the biomechanical results, merit further investigation.     

Effects of short-term trimethoprim-sulfamethoxazole administration on thyroid function in dogs

OBJECTIVE: To determine how rapidly trimethoprim-sulfamethoxazole affects serum total thyroxine (T4) and thyroid-stimulating hormone (TSH) concentrations in euthyroid dogs and how quickly hormone concentrations return to reference values following discontinuation of administration. DESIGN: Prospective study. ANIMALS: 7 healthy euthyroid dogs. PROCEDURE: Dogs were given trimethoprim-sulfamethoxazole (26.5 to 31.3 mg/kg [12 to 14.2 mg/lb], PO, q 12 h) for a maximum of 6 weeks. A CBC and Schirmer tear test were performed and serum total T4 and TSH concentrations were measured weekly. Administration of trimethoprim-sulfamethoxazole was discontinued if total T4 concentration was less than the lower reference limit and TSH concentration was greater than the upper reference limit or if persistent neutropenia developed. RESULTS: Six dogs had total T4 concentrations less than the lower reference limit within 3 weeks; T4 concentration was decreased after 1 week in 3 of these 6 dogs. In these 6 dogs, TSH concentration was greater than the upper reference limit within 4 weeks. In 1 dog, T4 and TSH concentrations were not affected, despite administration of trimethoprim-sulfamethoxazole for 6 weeks. Neutropenia developed in 4 dogs. In 1 dog, the neutropenia resolved while trimethoprim-sulfamethoxazole was still being administered. In the other 3, neutrophil counts returned to reference values 1 week after drug administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of trimethoprim-sulfamethoxazole at a dosage of 26.5 to 31.3 mg/kg, PO, every 12 hours can substantially alter serum total T4 and TSH concentrations and neutrophil counts in dogs within as short a time as a few weeks.     

Acute, subchronic, and chronic toxicity of ecadotril in dogs

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.     

Concurrent pituitary and adrenal tumors in dogs with hyperadrenocorticism: 17 cases (1978-1995).

OBJECTIVE: To describe the clinicopathologic characteristics of dogs with hyperadrenocorticism and concurrent pituitary and adrenal tumors. DESIGN: Retrospective study. ANIMALS: 17 client-owned dogs. PROCEDURE: Signalment, response to treatment, and results of CBC, serum biochemical analysis, urinalysis, endocrine testing, and histologic examinations were obtained from medical records of dogs with hyperadrenocorticism and concurrent adrenal and chromophobe pituitary tumors. RESULTS: On the basis of results of adrenal function tests and histologic examination of tissue specimens collected during surgery and necropsy, concurrent pituitary and adrenal tumors were identified in 17 of approximately 1,500 dogs with hyperadrenocorticism. Twelve were neutered females, 5 were males (3 sexually intact, 2 neutered); and median age was 12 years (range, 7 to 16 years). Hyperadrenocorticism had been diagnosed by use of low-dose dexamethasone suppression tests and ACTH stimulation tests. During high-dose dexamethasone suppression testing of 16 dogs, serum cortisol concentrations remained high in 11 dogs but decreased in 5 dogs. Plasma concentrations of endogenous ACTH were either high or within the higher limits of the reference range (12/16 dogs), within the lower limits of the reference range (2/16), or low (2/16). Adrenal lesions identified by histologic examination included unilateral cortical adenoma with contralateral hyperplasia (10/17), bilateral cortical adenomas (4/17), and unilateral carcinoma with contralateral hyperplasia (3/17). Pituitary lesions included a chromophobe microadenoma (12/17), macroadenoma (4/17), and carcinoma (1/17). CLINICAL IMPLICATIONS: Pituitary and adrenal tumors can coexist in dogs with hyperadrenocorticism, resulting in a confusing mixture of test results that may complicate diagnosis and treatment of hyperadrenocorticism.     

Evaluation of clinical status, renal function, and hematopoietic variables after unilateral nephrectomy in canine kidney donors

OBJECTIVE: To determine clinical status and renal and hematopoietic function after kidney donation and identify risks associated with kidney donation in dogs. DESIGN: Prospective study. ANIMALS: 14 dogs that underwent unilateral nephrectomy for kidney donation. PROCEDURES: Records were reviewed retrospectively to collect data regarding prenephrectomy clinicopathologic variables. Dogs were reexamined prospectively at various times after nephrectomy, and pre- and postnephrectomy CBC, serum biochemical analyses, urinalysis, and urine protein-to-urine creatinine ratio were compared. Six dogs had postnephrectomy renal volume determined ultrasonographically, and 4 of those dogs also underwent scintigraphic determination of glomerular filtration rate and renal biopsy. RESULTS: All dogs were clinically normal at the time of reevaluation. There were no significant differences between prenephrectomy and postnephrectomy values for BUN concentration or urine specific gravity. Mean postnephrectomy serum creatinine concentration was significantly greater than prenephrectomy concentration. Mean serum phosphorus concentration was significantly decreased after nephrectomy, and mean Hct, corpuscular volume, and corpuscular hemoglobin concentration were significantly increased after nephrectomy. Postnephrectomy renal volume was greatest in dogs < 12 months old at the time of surgery. Mean postnephrectomy glomerular filtration rate was 2.82 +/- 1.12 mL/kg/ min (1.28 +/- 0.51 mL/lb/min). Renal biopsy specimens obtained during and after nephrectomy were histologically normal. CONCLUSIONS AND CLINICAL RELEVANCE: Renal and hematopoietic variables were within reference ranges in dogs examined up to 2.5 years after unilateral nephrectomy. Compensatory renal hypertrophy was greatest in dogs < 1 year of age at donation. Donor age, along with histocompatability, may be an important factor in selecting dogs for kidney donation.     

Effects of meloxicam on renal function in dogs with hypotension during anaesthesia

OBJECTIVE: To evaluate the effects of meloxicam on renal function in dogs anaesthetized and rendered hypotensive with acepromazine-thiopental-isoflurane. ANIMALS: Eight healthy beagles, four males and four females, 25.6 +/- 19.3 months old and weighing 12.8 +/- 2.0 kg. MATERIALS AND METHODS: Either meloxicam suspension at a dose of 0.133 mL kg(-1) (0.2 mg kg(-1)) or 0.133 mL kg(-1) saline solution (control), were given by mouth (PO) in a randomized, cross-over fashion. The treatment or control was given 3 hours before anaesthesia. Dogs were sedated with intramuscular acepromazine 0.1 mg kg(-1). Anaesthesia was induced with intravenous thiopental, followed by tracheal intubation and maintenance with isoflurane in oxygen and air, delivered using a semi-closed breathing system. Renal function was quantified using serum biochemistry, urinalysis and glomerular filtration rate measured by scintigraphy. Analysis of variance or Friedman anova were used for statistical analysis. RESULTS: Values (mean +/- SD) for mean arterial blood pressure did not differ significantly between treatments but was low (54 +/- 7 mmHg) during anaesthesia. Glomerular filtration rate did not differ significantly between treatments or over time, and results of urine and serum analysis were within reference ranges after meloxicam treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Meloxicam caused no adverse effects on renal function when given to healthy dogs anaesthetized and rendered hypotensive with acepromazine, thiopental and isoflurane.     

Effect of trilostane on serum concentrations of aldosterone, cortisol, and potassium in dogs with pituitary-dependent hyperadrenocorticism

OBJECTIVE: To evaluate the effect of trilostane on serum concentrations of aldosterone, cortisol, and potassium in dogs with pituitary-dependent hyperadrenocorticism (PDH), compare the degree of reduction of aldosterone with that of cortisol, and compare aldosterone concentrations of healthy dogs with those of dogs with PDH. ANIMALS: 17 dogs with PDH and 12 healthy dogs. PROCEDURE: For dogs with PDH, the initial dose of trilostane was selected in accordance with body weight. A CBC count, serum biochemical analyses, and ACTH stimulation tests were performed in each dog. Dogs were evaluated 1, 3 to 4, 6 to 8, and 10 to 12 weeks after initiation of treatment. Healthy dogs were evaluated only once. RESULTS: Serum aldosterone concentrations before ACTH stimulation did not change significantly after initiation of treatment with trilostane. At each evaluation after initiation of treatment, serum aldosterone concentrations after ACTH stimulation were significantly lower than corresponding concentrations before initiation of treatment. The overall effect of trilostane on serum aldosterone concentration was less pronounced than the effect on serum cortisol concentration. Median potassium concentrations increased slightly after initiation of treatment with trilostane. Dogs with PDH had significantly higher serum aldo sterone concentrations before and after ACTH stimulation than healthy dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with trilostane resulted in a reduction in serum cortisol and aldosterone concentrations in dogs with PDH, although the decrease for serum aldosterone concentration was smaller than that for serum cortisol concentration. There was no correlation between serum concentrations of aldosterone and potassium during treatment.     

Effects of oral administration of controlled-ileal-release budesonide and assessment of pituitary-adrenocortical axis suppression in clinically normal dogs

OBJECTIVE: To evaluate the effects of oral administration of controlled-ileal-release (CIR) budesonide on the pituitary-adrenal axis in dogs with a normal gastrointestinal mucosal barrier. ANIMALS: 10 healthy dogs. PROCEDURES: 5 dogs received CIR budesonide orally once daily for days 1 through 28, and 5 dogs received placebo. Treatment group dogs that weighed < 18 kg received 2 mg of CIR budesonide; treatment group dogs that weighed > or = 18 kg received 3 mg of CIR budesonide. In the treatment and placebo groups, there were 3 and 2 dogs, respectively, that weighed > 18 kg. Plasma cortisol concentration before and after ACTH stimulation, basal plasma endogenous ACTH concentration, and body weight were measured on days 0, 7, 14, 21, 28, and 35. Serum biochemical analysis, CBC determination, and urinalysis were performed on days 0, 28, and 35. On days 7, 14, and 21, serum ALP and ALT activities, serum glucose concentration, and urine specific gravity were obtained in lieu of a full hematologic evaluation and urinalysis. RESULTS: Basal and post-ACTH stimulation plasma cortisol concentrations and plasma endogenous ACTH concentration were significantly suppressed by treatment. No other variables were altered over the course of the study. CONCLUSIONS AND CLINICAL RELEVANCE: Budesonide suppresses pituitary-adrenal function in dogs with normal gastrointestinal integrity, whereas other variables often affected by glucocorticoids were not altered by a 4-week treatment course. Budesonide may be a good alternative to traditional cortico-steroids if used short-term for acute exacerbations of inflammatory bowel disease.     

Preclinical evaluation of a liposome-encapsulated formulation of cisplatin in clinically normal dogs

OBJECTIVE: To determine the acute and short-term adverse effects of a liposome-encapsulated form of cisplatin at increasing dosages of up to twice the known maximally tolerated dose (MTD) of unencapsulated cisplatin in clinically normal dogs. ANIMALS: 4 healthy 2.5-year-old sexually intact female hound-type dogs. PROCEDURE: 4 dosages (70, 100, 125, and 150 mg/m2) were evaluated, and the 4 dogs received a total of 9 infusions (1 to 3 infusions/dog). Dogs were monitored to detect changes in clinical and clinicopathologic status. Evaluations consisting of a physical examination, CBC, serum biochemical analysis, and urinalysis were performed before and 7 and 21 days after each infusion. RESULTS: Acute anaphylactic-like reactions to liposome-encapsulated cisplatin were common but clinically manageable. Nephrotoxicosis and substantial myelosuppression, toxic effects commonly associated with unencapsulated cisplatin, were not observed in dogs treated with liposome-encapsulated cisplatin at dosages equivalent to twice the known MTD of unencapsulated cisplatin. CONCLUSIONS AND CLINICAL RELEVANCE: Liposome-encapsulated cisplatin can be safely administered to clinically normal dogs at dosages of up to 150 mg/m2 without the need for concurrent hydration protocols. This was a necessary prerequisite to enable phase I clinical trials in dogs with naturally developing cancers that could theoretically benefit from escalation in the dosage of cisplatin. Determination of an MTD, cumulative and long-term toxic effects, and efficacy can now be conducted in the context of phase I trials in tumor-bearing dogs.     

Effects of the alpha-glucosidase inhibitor acarbose on postprandial serum glucose and insulin concentrations in healthy dogs.

OBJECTIVE: To determine effects of acarbose on baseline and postprandial serum glucose and insulin concentrations in healthy dogs, if effects of acarbose were dosage related, and if acarbose caused any short-term adverse effects. ANIMALS: 5 healthy dogs fed a high-fiber diet. PROCEDURE: A Latin-square design was used. During each 1-week treatment period, dogs were given a placebo or 25, 50, 100, or 200 mg of acarbose, PO, twice daily immediately prior to feeding. There was a 1-week interval between periods. At the end of each treatment period, serum glucose and insulin concentrations were measured prior to feeding and at 30- to 60-minute intervals for 6 hours after feeding. RESULTS: Baseline serum glucose and insulin concentrations, insulin peak response, and total glucose absorption were not significantly different following treatment with placebo and treatment with acarbose; however, total insulin secretion was significantly decreased when dogs were treated with 100 or 200 mg of acarbose. Four dogs developed soft to watery stools when treated with 200 mg of acarbose, and 2 dogs lost weight during the study. Results of CBC and serum biochemical analyses were within reference ranges throughout the study. CONCLUSIONS: Acarbose did not induce any serious adverse effects and was effective in healthy dogs in reducing total postprandial insulin secretion when administered immediately prior to meals. CLINICAL RELEVANCE: Results suggest that acarbose may help control hyperglycemia in dogs with insulin-dependent diabetes mellitus. Additional studies designed to evaluate the effect of acarbose on postprandial blood glucose concentrations in dogs with diabetes mellitus are indicated.     

Serum total prostatic and non-prostatic acid phosphatase in healthy dogs and in dogs with prostatic diseases

Total acid phosphatase (TAP), prostatic acid phosphatase (PAP) and non-prostatic acid phosphatase (NPAP) serum concentrations were determined using a spectrophotometric technique in 52 healthy dogs, 15 male dogs suffering from non-prostatic diseases and in 19 dogs suffering from prostatic diseases (12 dogs with benign prostatic hypertrophy and seven dogs with prostatic adenocarcinoma). TAP, PAP and NPAP serum concentrations did not differ between normal male and normal female dogs. Dogs with prostatic adenocarcinoma had significantly higher TAP, PAP and NPAP serum concentrations than dogs with benign prostatic hypertrophy, normal dogs and dogs with non-prostatic disease. The authors conclude that low serum concentrations of TAP and PAP do not rule out prostatic adenocarcinoma in the dog, but elevated concentrations can be useful criteria for the diagnosis of canine prostatic cancer.     

Effects of sulfamethoxazole-trimethoprim on thyroid function in dogs

OBJECTIVE: To evaluate effects of trimethoprim-sulfamethoxazole (T/SMX) on thyroid function in dogs. ANIMALS: 6 healthy euthyroid dogs. PROCEDURE: Dogs were administered T/SMX (14.1 to 16 mg/kg, PO, q 12 h) for 3 weeks. Blood was collected weekly for 6 weeks for determination of total thyroxine (TT4), free thyroxine (fT4), and canine thyroid-stimulating hormone (cTSH) concentrations. Schirmer tear tests were performed weekly. Blood was collected for CBC prior to antimicrobial treatment and at 3 and 6 weeks. RESULTS: 5 dogs had serum TT4 concentrations equal to or less than the lower reference limit, and 4 dogs had serum fT4 less than the lower reference limit after 3 weeks of T/SMX administration; cTSH concentrations were greater than the upper reference limit in 4 dogs. All dogs had TT4 and fT4 concentrations greater than the lower reference limit after T/SMX administration was discontinued for 1 week, and cTSH concentrations were less than reference range after T/SMX administration was discontinued for 2 weeks. Two dogs developed decreased tear production, which returned to normal after discontinuing administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of T/SMX at a dosage of 14.1 to 16 mg/kg, PO, every 12 hours for 3 weeks caused decreased TT4 and fT4 concentrations and increased cTSH concentration, conditions that would be compatible with a diagnosis of hypothyroidism. Therefore, dogs should not have thyroid function evaluated while receiving this dosage of T/SMX for >2 weeks. These results are in contrast to those of a previous study of trimethoprim-sulfadiazine.