OBJECTIVETo determine whether injection of a mesenteric lymph node with iodinated aqueous contrast medium results in radiographic delineation of the thoracic duct and its branches, ascertain the ideal interval between injection and radiographic imaging, and evaluate mesenteric lymphadenography performed via laparoscopic and surgical approaches in dogs.ANIMALS10 adult dogs.PROCEDUREIn each dog, a right paracostal laparotomy or a right laparoscopic approach was performed to identify a mesenteric lymph node for injection of an iodinated aqueous contrast agent (0.22 mL/kg [81.4 mg of iodine/kg]). Lateral radiographic views were obtained at 60, 120, 180, 240, and 300 seconds after injection.RESULTSA mesenteric lymph node was identified and injected with contrast medium in each dog. Via paracostal laparotomy, lymph node injection resulted in successful lymphangiographic evaluation in 4 of 5 dogs, whereas via the laparoscopic approach, lymph node injection resulted in successful lymphangio-graphic evaluation in 2 of 5 dogs. In successful radiographic evaluations, injected lymph nodes, mesenteric lymphatics, and the thoracic duct and its branches were delineated. Radiographs obtained at 60 and 120 seconds after injection of contrast medium provided the most detail.CONCLUSIONS AND CLINICAL RELEVANCEInjection of a mesenteric lymph node directly with contrast medium appears to be a feasible technique for delineation of the thoracic duct and its branches in dogs and might be useful in small animals in which mesenteric lymphatic catheterization can be difficult and lymphangiography is more likely to fail. Refinement of the laparoscopic technique may provide a minimally invasive approach to lymphadenography.

OBJECTIVE To evaluate use of transcranial magnetic motor evoked potentials for assessment of the functional integrity of the cervical spinal cord in large-breed dogs with cervical spinal cord disease. DESIGN Randomized, controlled, masked study. ANIMALS 10 healthy large-breed control dogs and 25 large-breed dogs with cervical spinal cord diseases. PROCEDURE Affected dogs were allocated to 3 groups on the basis of neurologic status: signs of neck pain alone, ambulatory with ataxia in all limbs, or nonambulatory. Transcranial magnetic stimulation was performed on each dog with the same standard technique. Motor evoked potentials (MEP) were recorded from electrodes inserted in the tibialis cranialis muscle. Following the procedure, each dog was anesthetized and cervical radiography, CSF analysis, and cervical myelography were performed. The MEP latencies and amplitudes were correlated with neurologic status of the dogs after correction for neuronal path length. RESULTS Mean MEP latencies and amplitudes were significantly different between control dogs and dogs in each of the 3 neurologic categories, but were not significantly different among dogs in the 3 neurologic categories. A linear association was evident between MEP latencies and amplitudes and severity of neurologic deficits; the more severe the neurologic deficits, the more prolonged the latencies and the more decreased the amplitudes. CONCLUSIONS AND CLINICAL RELEVANCE Transcranial magnetic MEP are useful to assess severity of cervical spinal cord disease in large-breed dogs. Impairment of the functional integrity of the cervical spinal cord was found even in dogs with neck pain alone.

A case of feline acromegaly was successfully treated by cryosurgical ablation of the pituitary gland (1). Unfortunately, abrupt resolution of insulin-resistant diabetes mellitus 2 mo postoperatively resulted in a hypoglycemic crisis due to insulin overdose. The crisis was characterized clinically by hypothermia, coma, seizures, and constricted, nonresponsive pupils. The cat's condition stabilized over 24 h, but it had become blind, in addition to having poor physiologic nystagmus and proprioceptive deficits, and, 1 mo later, aggressive behavioral changes. Blindness during this early period was attributed to acute cerebral cortical necrosis. Neurologic deficits other than behavioral changes resolved over 3 mo, but the cat remained blind for the next 9 mo, at which time it was euthanized. Blindness during this later period was attributed to retinal degeneration based on clinical findings, electroretinography, and, ultimately, histopathologic findings. The retinal degeneration was unexplained in the original report (1). The purpose of this report is to provide additional details of the case, including therapy with enrofloxacin (Baytril; Bayer, Toronto, Ontario), which, we now believe, was responsible for the retinal degeneration and permanent blindness. The day of insulin overdose is referred to as day 0. Pupillary light reflexes were normal by day 3. No abnormalities were noted on a complete ophthalmologic examination on day 7, other than an absent menace response; however, the cat did orient and respond to bright light, suggesting that it was not completely blind. On day 17, the cat could negotiate an obstacle course, had some following eye movements, and would orient towards minimally odiferous, isolated objects placed in its path. The consensus was that the cat had definitely regained some vision, but progressive improvement beyond that time was not observed. On day 45, persistent pupillary dilation was noted. Ophthalmologic examination revealed bilateral retinal degeneration, characterized by absent pupillary light reflexes, tapetal hyperreflectivity, optic nerve atrophy, and attenuation of retinal vessels. There was no activity on an electroretinogram. Findings were similar prior to euthanasia. On histopathological examination of the eyes, lesions were restricted to the retina. There was complete photoreceptor atrophy and loss of the outer nuclear layer, with retention of the inner nuclear layer and ganglion cells. The optic chiasm and optic tracts had widespread vacuolation and widely scattered axonal necrosis, indicating that cryoinjury to these tissues had occurred at the time of cryohypophysectomy. However, the optic nerves, nerve fiber layer, and ganglion cells were normal, indicating that degeneration of the outer retinal layer was not a result of a “dying-back” process from previous cryoinjury to the optic tracts (1). A problem not discussed in the original report was urinary retention and urinary tract infection. The cat did not urinate well for approximately 6 wk following day 0, and developed a large, flaccid bladder. This was managed with indwelling and intermittent urethral catheterization, as well as with bethanecol (Urecholine; Frosst, Kirkland, Quebec), 0.5 mg/kg bodyweight (BW), q8h, from days 16 to 21. Urethral catheterization resulted in recurrent and resistant urinary tract infections with Escherichia coli and Enterobacter aerogenes. Pyelonephritis was suspected on the basis of an elevated serum creatinine level (193 μmol/L; reference range 75 to 180 μmol/L) and an inappropriately low urine specific gravity of 1.024. The urinary tract infection was treated at different times with amoxicillin (Moxilean; Bimeda-MTC Animal Health, Cambridge, Ontario), 20 mg/kg BW, PO, q8h; amoxicillin-clavulanate (Clavamox; Ayerst Veterinary Laboratories, Guelph, Ontario), 25 mg/kg BW, PO, q12h; and trimethoprim-sulfadiazine (Tribrissen; Schering Canada, Pointe-Claire, Quebec), 18 mg/kg BW, PO, q12h. Treatment with enrofloxacin was then started on day 37. The initial dosage prescribed by the attending clinician was 68 mg, PO, q8h, representing a daily dose of 40 mg/kg BW (It is acknowledged that this dose is well above the label dosage at the time (January 1991, 2.5 mg/kg BW, q12h), and above the label dosage change in July 1997 (5 to 20 mg/kg BW/d)). The dosage was reduced to 68 mg, PO, q12h (daily dose 27 mg/kg BW), 4 d later (day 41), and further reduced to 23 mg, PO, q12h (daily dose 9 mg/kg BW), 2 d after that (day 43). Enrofloxacin was continued at 23 mg, PO, q12h, for another 34 d. Urine cultures during the enrofloxacin therapy, 6 wk after discontinuing the therapy, and prior to euthanasia were negative. Chronic renal failure did not develop. Histopathologic findings in the kidney were consistent with chronic pyelonephritis. Another problem not discussed in the original case report was hepatopathy attributed to phenobarbital. Phenobarbital (Phenobarbital; Parke-Davis, Scarborough, Ontario), 2 mg/kg BW, PO, q12h, was given to control seizures, beginning on day 10. On day 33, the alanine aminotransferase (ALT) level was elevated at 917 U/L (reference range, 10 to 75 U/L), in contrast to 51 U/L 2 d prior to beginning the phenobarbital treatment. The phenobarbital level was 145.51 μmol/L, well within the therapeutic range (65 to 172 μmol/L). Hepatic failure did not occur, based on a normal serum bilirubin level and an ammonia tolerance test. The phenobarbital treatment was rapidly tapered over 4 d, and was discontinued on the day that the enrofloxacin therapy began. The phenobarbital level 1 wk later (day 44) was 25.32 μmol/L and the ALT level 2 wk later (day 51) was normal at 65 U/L. Therapy with diazepam (Valium; Hoffman-LaRoche, Mississauga, Ontario), 0.5 mg/kg BW, PO, q12h, was started concurrently with enrofloxacin and continued for 15 d. A final previously unreported problem was idiopathic constipation, diagnosed prior to the onset of diabetes mellitus. This had been treated over a period of time with lactulose (Acelac; Technilab, Mirabel, Quebec), 2 to 3 mL added to 3 or 4 daily meals. Although this cat had had numerous problems and had been treated with numerous drugs, the retinal degeneration could not be satisfactorily explained at the time of the original report. We hypothesized that it might have been a case of sudden acquired retinal degeneration (SARD), although, to our knowledge, at that time and since then, a case of feline SARD has not been documented. A toxic insult to the retinas was considered, but none of the drugs used in this cat had been associated with retinopathy at that time. However, the association of enrofloxacin and visual disturbances in cats is now firmly established. In a letter circulated to Canadian veterinarians, dated July 6, 2000, Bayer Inc. reported an accumulating number of anecdotal reports of visual impairment following the use of Baytril in cats. This prompted further investigations where normal cats were treated with enrofloxacin at doses ranging from 5 to 50 mg/kg BW for 21 d. In a subsequent letter, dated April 10, 2001, Bayer Inc. reported, “The administration of enrofloxacin at 20 mg/kg body weight or greater resulted in mild to severe retinal degeneration, abnormal electroretinograms, and microscopic changes in the retina.” Detailed results of the toxicity study are to be published in the future (personal communication, Kathleen Keil, Bayer Inc.). The first report of a clinical study of enrofloxacin-associated retinal degeneration was published recently (2). In this study, daily doses of enrofloxacin in 16 cats ranged from 6 to 54 mg/kg BW; 1 cat was treated at 4.6 mg/kg BW. The onset of visual disturbances was observed in from 2 d to more than 12 wk; it occurred in less than 10 d in at least 7 cats. Most cats had permanent blindness. The eyes of 1 blind cat were examined histologically — lesions included diffuse retinal degeneration affecting the outer nuclear and photoreceptor layers, while the inner retinal layers were preserved to some extent. With our case, a high dose of the drug had been given for 8 d prior to the retinal degeneration being detected. Marginal renal dysfunction may have further increased the plasma levels of the drug. The rapid onset of blindness is consistent with that observed in the above mentioned study (2) and in other presumptive cases of enrofloxacin-induced blindness collectively seen by the authors. Furthermore, following a toxic insult to the retina, the appearance of ERG changes within the time frame seen in this case is also expected. Finally, the histopathologic lesions in the previously reported case (2) and in our case were similar. In conclusion, in the absence of another explanation, it appears that the use of enrofloxacin was responsible for the retinal degeneration and contributed to the permanent blindness that developed in our case. Although visual disturbances following the use of enrofloxacin at the currently recommended daily dose of 5 mg/kg BW in cats appear to be rare, the high dose of the drug that was used in our case is now known to cause retinal degeneration. Enrofloxacin-induced retinal degeneration is occasionally reversible (2), but the prolonged course of therapy at the dosage used in this cat would have probably eliminated the possibility of it occurring. The effect, if any, of concurrent phenobarbital and diazepam blood levels on the retinal toxicity of enrofloxacin is not known.

Renal allografts were performed between unrelated donors and 15 dogs with naturally occurring end-stage renal disease. Donor selection was based on compatible dog erythrocyte antigen typing and cross-matching. An immunosuppressive protocol consisting of rabbit antidog antithymocyte serum, cyclosporin-A, azathioprine, and prednisone was used to control postoperative rejection of the donated kidney. Although seven animals died because of technical failures or rejection episodes, a median survival time of eight months has been achieved, with two dogs living for longer than five years after surgery. Long-term survivors have died from a variety of problems not related to renal allograft rejection.

Summary A retrospective case series study was done to determine the long-term outcome of operations upon dogs treated for canine hip dysplasia by means of a triple pelvic osteotomy (TPO). Twentyfour dogs with bilateral hip dysplasia, that received a unilateral TPO between January 1988 and June 1995, were re-examined at the Ontario Veterinary College. The assessment included physical, orthopedic and lameness examinations, standard blood work, pelvic radiographs and force plate gait analysis. They were compared to bilaterally dysplastic dogs that had not been treated, and also to normal dogs. Force plate data analysis demonstrated a significant increase in peak vertical force (PVF) and mean vertical force over stance (MVF) in the limb that underwent surgical correction by means of a TPO, when compared to the unoperated hip. It was determined that performing a unilateral TPO on a young dysplastic dog resulted in greater forces and weight bearing being projected through the TPO corrected limb when compared to the unoperated limb. Dogs with bilateral hip dysplasia treated with a unilateral triple pelvic osteotomy (TPO) were assessed by force plate gait analysis, radiographs and orthopedic examination. There was a significant increase in hip Norberg angles over time, although degenerative changes did progress. Limbs that had been operated upon had significantly greater peak and mean ground reaction forces than limbs that had not received an operation.

The use of screws placed from the articular surface in lag fashion for the repair of proximal femoral physeal fractures has been reported experimentally and clinically with mixed results. This report describes the use of the technique in the repair of a fractured proximal humeral physis.

OBJECTIVE:To compare the biomechanical properties of five intramedullary (IM) pin fixation techniques for Salter-Harris type I fractures of the distal femur in dogs.STUDY DESIGN:Randomized, one-way factorial design composed of five treatment groups: (1) single IM pin, (2) dynamic IM crossed pins, (3) paired convergent pins, (4) crossed pins, and (5) crossed polyglycolic acid (PGA) rods.SAMPLE POPULATION:Forty pairs of cadaver canine femurs.MATERIALS:One femur of each pair was manually fractured and subsequently repaired; the contralateral intact femur served as its control. Each femur was loaded in torsion until-failure occurred and load-deformation curves were generated.RESULTS:The crossed-pin technique sustained the greatest load to failure (116.8%) followed by the paired convergent pins (104.8%), dynamic IM pins (90.6%), single IM pin (72.1%), and crossed PGA rods (71.9%). Statistically significant differences in strength at failure were detected between the crossed-pin and single IM pin and the crossed-pin and crossed PGA rod techniques. All fixation techniques underwent greater deformation (1.5 times as much) and had a lower stiffness (66% to 75%) compared with the intact controls; however, there was no significant difference between techniques. Failure in the paired convergent and crossed-pin techniques occurred by fracture of the bone; failure in the other techniques occurred by distraction at the fracture site.CONCLUSION:The rotational stability of any of the fixation techniques appears to be primarily determined by the ability to prevent distraction and maintain interdigitation of the physis.CLINICAL RELEVANCE:When choosing a particular fixation technique for repair of a distal femoral physeal fracture, consideration should be given to the technique's relative biomechanical merits.

Objective-To evaluate the population characteristics; historical, clinical, and diagnostic findings; and treatment outcome of dogs with thoracolumbar intervertebral disk disease (IVDD) whose only clinical signs were those of back pain.Design-Retrospective case series.Animals-Dogs with IVDD and clinical signs of back pain only, without neurologic deficits, in which survey radiography of the vertebral column and diagnostic myelographic studies were performed.Procedure-Review of the medical record, evaluation of survey radiographs of the vertebral column, evaluation of myelograms and estimation of apparent extent of spinal cord compression, and follow-up information provided by telephone contact with owners.Results-Spinal cord compression was detected on myelography in 20 of 25 (80%) dogs. Treatment included decompressive surgery in 18 of 25 (72%) dogs and all dogs underwent intervertebral disk fenestration. The condition was improved in 24 of 25 (96%) dogs after surgery.Clinical Implications-Dogs with thoracolumbar IVDD that have clinical signs of back pain alone, without neurologic deficits, may have substantial compression of the spinal cord.

Fifty-four dogs with primary tumors of the rib were evaluated. Thirty-four dogs had osteosarcomas, 15 dogs had chondrosarcomas, three dogs had hemangiosarcomas, and two dogs had fibrosarcomas. Forty-nine dogs had en bloc excision. Within the osteosarcoma group, nine animals received postoperative adjuvant chemotherapy. These animals had significantly longer median disease-free intervals (225 days) and median survival times (240 days) than dogs with osteosarcoma treated by surgery alone (median disease-free interval, 60 days; median survival, 90 days). Chondrosarcoma had a better prognosis (median disease-free interval, 1,080 days; median survival, 1,080 days) than osteosarcoma, hemangiosarcoma, or fibrosarcoma of the rib. Age, weight, sex, number of ribs resected, tumor volume, and total cisplatin dose did not influence survival nor disease-free interval.

Therapeutic renal transplantation in dogs is currently being investigated as a treatment for endstage renal disease. This pilot study examines the effect of donor bone marrow (DBM) infusion and antithymocyte serum (ATS) in combination with immunosuppressive drug therapy in prolonging renal allograft survival in dogs. Seven normal outbred mongrel dogs received an unmatched renal allograft. All dogs received rabbit anti-dog thymocyte serum (RADTS), prednisone (Pr), cyclosporine-A (CsA) and azathioprine (Aza). In addition, three dogs (group 1 test) received DBM and four dogs (group 2 control) did not receive DBM. Serum CsA levels were measured throughout the study. Immunosuppressive therapy was gradually reduced with Pr, CsA, and Aza withdrawn at 200, 450, and 680 days, respectively. Allograft rejection was treated with prednisolone sodium succinate. One dog in group 1 and one in group 2 died as a result of infectious canine rhinotracheitis and rejection early in the study. Renal allograft torsion occurred in one group 1 dog. The remaining four dogs survived the 2 years of the study. The dogs in group 2 (three dogs) all rejected the renal allograft after total drug withdrawal, the surviving dog in group 1 did not. This study demonstrates that RADTS, Pr, CsA, and Aza in combination can prolong renal allograft survival in mongrel dogs, whereas DBM may enhance the unresponsive state.

SummaryTo reduce postoperative complications due to pelvic canal narrowing following triple pelvic osteotomy, it is important to minimize the length of the pubic remnant on the acetabular segment. Three different techniques for performing the pubic osteotomy were compared: a lateral wire saw technique, a lateral osteotome technique and a ventral osteotome ostectomy technique. The lateral wire saw and ventral ostectomy techniques resulted in significantly shorter pubic remnants than the lateral osteotome technique. The osteotomies performed with the wire saw were more accurate and precise than those performed with the osteotome. The lateral wire saw technique is a practical alternative to the ventral ostectomy technique for performing the pubic osteotomy.A comparison of three different pubic osteotomy techniques for the triple pelvic osteotomy showed that minimal pubic remnants can be achieved with either the lateral wire saw or ventral ostectomy technique. Osteotomies made by the wire saw were more accurate and precise than those made by the osteotome.

To reduce postoperative complications due to pelvic canal narrowing following triple pelvic osteotomy, it is important to minimize the length of the pubic remnant on the acetabular segment. Three different techniques for performing the pubic osteotomy were compared: a lateral wire saw technique, a lateral osteotome technique and a ventral osteotome ostectomy technique. The lateral wire saw and ventral ostectomy techniques resulted in significantly shorter public remnants than the lateral osteotome technique. The osteotomies performed with the wire saw were more accurate and precise than those performed with the osteotome. The lateral wire saw technique is a practical alternative to the ventral ostectomy technique for performing the pubic osteotomy.

Characteristic alterations in the serum and urine biochemical profiles of Doberman Pinschers with congestive heart failure (CHF) resulting from idiopathic dilated cardiomyopathy were determined. We compared these alterations with those observed in 2 other models of CHF: rate overload induced by rapid ventricular pacing in dogs, and biventricular hypertrophy and dilatation induced in turkey poults by furazolidone toxicosis. Serum and urine biochemical changes in both models of CHF in dogs were mild to moderate in degree, and were moderately consistent. They could be attributed to secondary neurohumoral, hepatic, and renal effects of heart failure. The most marked and consistent changes observed were mildly decreased anion gap that developed, in part, because of decreased serum sodium concentration, moderately increased catecholamine concentrations, moderate lactaciduria, hyposthenuria, and mildly increased urea concentrations and liver enzyme activities. In birds with furazolidone cardiomyopathy, we observed mild increases in serum urate concentration, liver and muscle enzyme activities, but moderately increased sodium concentration with decreased chloride concentration. In the pacing and furazolidone models, in which CHF was rapidly induced, moderate to marked hypoproteinemia was attributable to decreases in albumin and globulin concentrations. Using the avian model we found that the hypoproteinemia could be largely attributed to blood volume expansion, and to a lesser extent, inanition. Development of hypoalbuminemia during rapid ventricular pacing and furazolidone treatment may contribute to the effects of rate overload or drug toxicity in the pathogenesis of CHF, because hypoalbuminemia may contribute to altered hemodynamics and neuroendocrine system activation. Our data indicate that clinical biochemical analysis of serum and urine may be useful for assessing progression of CHF.

Magnetically elicited transcranial motor evoked potentials (MEPs) were studied in 37 dogs with type 1 intervertebral disc (IVD) disease. The waveforms were recorded from both cranial tibial muscles before and after surgery. The latencies and amplitudes obtained were compared to those of a control population (n = 14). MEPs were recordable in all dogs with mild or no neurologic deficits, but they were recordable in only 50% of ambulatory dogs that were severely ataxic. MEPs could not be elicited from nonambulatory dogs. There was a significant attenuation of the amplitudes in all clinical cases, even if the dogs demonstrated back pain alone. Significantly prolonged latencies were associated with neurologic deficits. MEPs were not good predictors of neurologic recovery. The responses obtained from the side where the disc material was found were not different from those recorded from the opposite side. MEPs were very sensitive to lesions of the spinal cord, as indicated by the significant changes in the waves in patients with mild or no neurologic deficits and in the loss of response in dogs that still demonstrated purposeful movement. Neurologic exams provided more accurate diagnoses and prognoses than did MEPs in dogs with IVD disease.

An eight-year-old, male neutered, domestic longhair cat weighing 6.5 kg was presented with a two-month history of polyphagia. The owners reported that the cat had always had a generous appetite but was now becoming destructive when seeking food. Three episodes of hyperglycemia (12.3 mmol/L-18. 1 mmolIL, reference values 3.5 mmol/L-9.0 mmol/L) and glucosuria (56-111 mmol/L), and on one occasion ketonuria (0.5 mmol/L), had occurred in association with consti-pation during the previous ten months, but had been resolved without insulin therapy. No abnormalities other than obesity were noted on physical examination. Results of a complete blood count, serum chemistry profile, and urinalysis were unremarkable. Hyperthyroidism and hyperadrenocorti-cism were considered to be possible causes of the cat's polyphagia. The serum thyroxine level was 10 nmol/L (reference values 9.3 nmol/L-57.9 nmol/L). An adreno-corticotropic hormone (ACTH) stimulation test (1) was performed. Serum cortisol levels assayed before, and at 30 and 60 minutes after, intramuscular (IM) administration of a total dose of 0.125 mg cosyntropin (Cortrosyn, Organon Canada, West Hill, Ontario) were 229 nmolIL, 270 nmol/L, and 276 nmol/L, respectively. These results were considered to be normal and no treatment was instituted. Six weeks later the cat was for evaluation of polyuria/polydipsia an polyphagia of two weeks' No noted on physical than mild

Clinical esophageal reconstruction in dogs is generally limited to the repair of small segments of cervical and terminal thoracic esophagus. The attempt was made to develop a procedure for the replacement of the entire thoracic esophagus. Three groups of dogs were used for microvascular colon transfers. Five dogs received orthotopic colon autografts. A segment of cervical esophagus was replaced in three dogs, and the entire thoracic esophagus was bypassed in six dogs. The orthotopic grafts worked well and the surviving dogs had normal stools within 48 hr of surgery. The cervical grafts all remained viable, and dogs were able to drink normally and swallow gruel from elevated bowls. Chronic regurgitation of solid food due to inadequate graft motility was an unresolved problem. All thoracic esophageal bypass grafts failed because of mechanical kinking of the vascular pedicles and leakage.

Urinary diversion by implantation of the ureters into an isolated segment of jejunum was evaluated in eight clinically normal male dogs. Total cystectomy and subtotal intracapsular prostatectomy were performed, and the intestinal loop was sutured to the prostatic remnant. General health, renal function, acid-base balance, urinary tract infection, and urinary continence were monitored during observation periods of 4 to 30 weeks. All dogs survived the observation period and seven were in excellent general health at the time of euthanasia. Six of the 16 ureterointestinal anastomoses were complicated by complete ureteral obstruction. Absorption of urea from the intestinal loop was speculated as the reason for significant increases in serum urea nitrogen concentrations in all of the dogs. Serum creatinine concentrations generally remained within the normal range, but were significantly increased from preoperative baseline values by week 30. There was dilation of 12 renal pelves and ureters in seven dogs. Urine bacterial cultures were positive in six dogs, but histologic evidence of pyelonephritis was present in only five kidneys. Ejaculation was not affected by the procedure, but epididymitis was present in five dogs. The dogs could urinate consciously and did not dribble urine continuously; however, they urinated hourly. While the procedure was well tolerated by the dogs, the frequency of urination makes this technique unacceptable for most household pets.