Mushroom toxicosis in dogs in general practice causing gastroenteritis,ptyalism and elevated serum lipase activity

Mushroom toxicosis is rarely diagnosed in dogs and is poorly reported in the veterinary literature. This report suggests that mushroom toxicosis is a potentially under‐diagnosed condition in first opinion practice in the UK. Nine dogs with clinical signs consistent with mushroom toxicosis were identified from the records of an out‐of‐hours emergency service between August 2010 and January 2011. Four dogs were later excluded because of clinical inconsistencies. Clinical signs included acute profuse ptyalism (5/5), diarrhoea (5/5), vomiting (4/5), hypovolaemia (4/5), stuporous (3/5) or obtunded mentation (1/5), miosis (2/5) and hypothermia (2/5). Serum lipase activity was elevated in 4/4 dogs; canine‐specific pancreatic lipase was elevated in the remaining dog. Four dogs recovered with aggressive intravenous fluid therapy, analgesia and supportive care; the remaining dog was euthanased due to severe clinical signs and financial constraints. Mushroom toxicosis is an important differential diagnosis for acute gastroenteritis and one possible cause of some cases of “Seasonal Canine Illness”. Affected dogs may demonstrate elevated pancreatic enzymes and mushroom toxicosis should be considered in cases of elevated lipase or abnormal semi‐quantitative canine‐specific pancreatic lipase activities.     

Treatment of chronic lymphocytic leukaemia in three dogs with melphalan and prednisolone

Three adult dogs with chronic lymphocytic leukaemia (CLL) were successfully treated with melphalan and prednisolone. Based on the immunophenotypic analysis of leukaemic cells, two dogs were diagnosed with B cell CLL and one dog was tentatively diagnosed as having T cell CLL. One dog with B cell CLL had IgM monoclonal gammopathy. The clinical signs and haematological abnormalities associated with CLL in the three dogs improved with the administration of cytoreductive melphalan (3 to 5 mg/m2/day) and prednisolone (4.3 to 30 mg/m2/day) for eight to 210 days. There were no severe adverse effects except a mild increase in plasma alkaline phosphatase activity. Melphalan and prednisolone therapy may achieve remission with few side effects in dogs with CLL.     

Rectal strictures in 19 dogs: 1997-2005

The etiologies for nonneoplastic rectal strictures in dogs included foreign bodies, postoperative formation, inflammatory disease, and congenital malformation. Sixteen of 19 dogs underwent balloon dilatation therapy, and 14 of these 16 dogs received intralesional triamcinolone injections. Following dilatation, clinical signs persisted in one dog, improved with continued medical therapy in five dogs, and resolved in nine dogs for the duration of their follow-up period (mean 18 months; median 12 months); one dog was lost to follow-up. Balloon dilatation and triamcinolone were parts of a treatment regimen that improved clinical signs in the majority of dogs diagnosed with nonneoplastic rectal strictures.     

Ureterocolonic anastomosis in clinically normal dogs

Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degrees of metabolic acidosis, hyperammonemia, and neurologic disease may result.     

Myopathy associated with hyperadrenocorticism in the dog

Naturally occurring or iatrogenic hyperadrenocorticism was associated with myopathy in six dogs. One dog had muscle weakness and muscle atrophy but normal electromyographic findings. Five dogs had muscle stiffness, proximal appendicular muscle enlargement, and myotonic discharges on electromyography. Histologic, electron microscopic, and histochemical findings in the musculature of dogs that were examined were characteristic of noninflammatory degenerative myopathy. Clinical signs of the myopathy improved to varying degrees in five dogs that were treated for the hyperadrenocorticism.     

Chronic active hepatitis in 26 Doberman pinschers

Chronic active hepatitis with increased hepatic copper concentration was diagnosed in 25 female and 1 male Doberman Pinscher dogs. Common clinical signs included polyuria/polydipsia, weight loss, anorexia, icterus, and ascites. Increased liver enzyme activities and abnormal liver function test results were the most consistent clinicopathologic changes. The dogs were assigned to 3 groups on the basis of clinical course of the disease. Group 1 dogs (n = 12) had clinical signs of advanced liver failure and died within one week. Group 2 dogs (n = 7) had less severe clinical signs of liver disease and died within one month. Group 3 dogs (n = 5) did not have clinical signs of illness or had mild clinical signs of liver disease and died 1 to 42 months after initial evaluation. One dog could not be reevaluated and another dog was alive 3 months after initial examination. Treatments consisted of supportive care for dogs in group 1, and dietary manipulations and corticosteroids for dogs in groups 2 and 3. The association of increased liver copper concentration and chronic active hepatitis is not known.     

Cranial mediastinal carcinomas in nine dogs*

Nine dogs were diagnosed with cranial mediastinal carcinomas. Based on histological and immunohistochemical analysis, four dogs were diagnosed with ectopic follicular cell thyroid carcinomas, one dog with ectopic medullary cell thyroid carcinoma, two dogs with neuroendocrine carcinomas and two dogs with anaplastic carcinomas. Clinical signs and physical examination findings were associated with a space‐occupying mass, although one dog was diagnosed with functional hyperthyroidism. Surgical resection was attempted in eight dogs. The cranial mediastinal mass was invasive either into the heart or into the cranial vena cava in three dogs. Resection was complete in six dogs and unresectable in two dogs. All dogs survived surgery, but four dogs developed pulmonary thromboembolism and two dogs died of respiratory complications postoperatively. Adjunctive therapies included pre‐operative radiation therapy (n = 1) and postoperative chemotherapy (n = 3). Three dogs had metastasis at the time of diagnosis, but none developed metastasis following surgery. The overall median survival time was 243 days. Local invasion, pleural effusion and metastasis did not have a negative impact on survival time in this small case series.     

Spirocerca lupi esophageal granulomas in 7 dogs: resolution after treatment with doramectin

Seven dogs with Spirocerca lupi esophageal granulomas were identified based on the site of involvement (ie, distal esophagus) and characteristic endoscopic appearance. Six dogs presented with signs of esophageal disease and 1 dog was asymptomatic. Ova were only identified in the feces of 2 dogs. On thoracic radiographs, 4 dogs had evidence of a caudodorsal mediastinal mass, and 2 of these dogs had spondylitis of midthoracic vertebrae. On endoscopy, single esophageal nodules were observed in 5 dogs, 1 dog had 3 nodules, and 1 dog had 6 nodules. All 7 dogs were treated with doramectin at a dosage of 200 microg/kg SC at 14-day intervals for 3 treatments. Dogs had physical and endoscopic examinations at 2, 4, and 6 weeks after treatment. By 6 weeks, clinical signs had resolved in 6 dogs (1 dog was asymptomatic), and the esophageal nodules had completely resolved in 4 dogs, and incompletely resolved in 3 dogs. Two dogs with incomplete resolution were treated again with doramectin at 500 microg/kg PO daily for an additional 6 weeks. Complete resolution of the esophageal nodules was confirmed by endoscopy in all dogs. Nodules had resolved in 4 dogs by 6 weeks, in 2 dogs by 12 weeks (after 6 weeks additional daily oral therapy), and in 1 dog 22 months after the initial 200 microg/kg treatment regimen. No dog experienced adverse effects to the drug, and all symptomatic dogs have been free of disease for periods ranging from 3 to 4 years.     

Canine inflammatory myopathies: a clinicopathologic review of 200 cases

A retrospective study was performed on 200 randomly selected cases of inflammatory myopathy in dogs from diagnostic muscle biopsies received at the Comparative Neuromuscular Laboratory, University of California, San Diego. The most common clinical signs in dogs diagnosed with an inflammatory myopathy were generalized weakness, stilted gait, dysphagia, masticatory or generalized muscle atrophy, inability to open the jaw, megaesophagus, and dysphonia. Myalgia was rarely described. Age of onset ranged from 0.25 to 14 years. Genders were equally represented. Breed distribution approximated the 2002 American Kennel Club registration statistics (r = .85) with the notable exception of Boxers and Newfoundlands. From the results of muscle biopsies, clinical signs, and presence or absence of antibodies against type 2M fibers, dogs were classified as a generalized inflammatory myopathy (gIM)--including immune-mediated polymyositis; infectious and preneoplastic myositis; and, rarely, dermatomyositislike or overlap syndromes or unclassified myositis-or a focal inflammatory myopathy (flM)--including masticatory muscle and extraocular myositis. Average creatine kinase (CK) and aspartate aminotransferase (AST) concentrations in gIMs were significantly higher than those with fIMs (P < .05). Neoplasia developed in 12 of 200 dogs within 12 months of diagnosis of polymyositis, with lymphoma diagnosed in 6 of 32 Boxers. Inflammatory myopathy was associated with antibody titers against infectious diseases in 38 dogs. Neospora caninum and Hepatozoon americanum cysts were found in tissues of 2 dogs not serologically tested. Antibodies against an unidentified sarcolemmal antigen were found in 9 of 19 Newfoundlands with polymyositis. The spectrum of canine inflammatory myopathies can be broad, with infectious etiologies relatively common, and can include preneoplastic and uncharacterized syndromes.     

Bilateral Iliopsoas Muscle Contracture and Spinous Process Impingement in a German Shepherd Dog

Objective— To report diagnosis and treatment of bilateral iliopsoas muscle contracture in a dog with spinous process impingement. Study design— Case report. Animals— German Shepherd dog. Methods— A dog with chronic progressive lameness, flexion contracture of the coxofemoral joints, severe pain, and decreased femoral reflexes had severe spondylosis bridging the vertebral bodies from L1 to L4 and enlarged dorsal spinous processes from T8 to L6 with impingement and bony proliferation. Ultrasonographic and magnetic resonance imaging (MRI) findings were consistent with fibrosis, mineralization, and atrophy of the iliopsoas muscles bilaterally which was treated by staged tenectomy of the insertions of the iliopsoas muscles. Results— Because of severe perivascular fibrosis, the femoral vessels required ligation. Bilateral iliopsoas muscle tenectomy improved gait and provided pain relief. Histologic findings were consistent with fibrotic myopathy. Conclusions— Slow progression of severe clinical signs observed bilaterally in this dog differs from previous reports of iliopsoas myopathy. Findings were similar to the fibrotic myopathy of the gracilis or semitendinosus muscles described in dogs. Clinical Relevance— Iliopsoas muscle abnormalities should be considered in dogs with limited hip extension and pain. MRI is useful for diagnosing muscle fibrosis. Iliopsoas tenectomy may improve clinical function in dogs with fibrotic myopathy.     

Acute blindness associated with intracranial tumors in dogs and cats: eight cases (1984-1989)

Rostral and middle cranial fossa tumors affecting the optic chiasm and resulting in acute visual deficits were diagnosed in 7 dogs and 1 cat. Blindness and dilated nonresponsive pupils were the primary signs in all animals. Other concurrent neurologic deficits were either absent or were equivocal. Behavioral changes, including signs of depression and lethargy, were noticed in 1 dog and the cat subsequent to the onset of blindness. Retinal function was assessed as normal by electroretinography in all animals. The histologic necropsy diagnosis was pituitary carcinoma in 1 dog and the cat and paranasal sinus carcinoma with intracranial extension in 1 dog. A cytologic diagnosis of polycentric lymphosarcoma affecting the optic chiasm was diagnosed in 1 dog. In the remaining 4 dogs, results of computed tomographic imaging or endocrine function testing suggested pituitary gland neoplasia. Four dogs were treated with cobalt-60 radiation or chemotherapy. There was partial return of visual function in only 1 of the dogs treated with radiation.     

Extradural spinal juxtafacet (synovial) cysts in three dogs

Three dogs were presented for investigation of spinal disease and were diagnosed with extradural spinal juxtafacet cysts of synovial origin. Two dogs that were presented with clinical signs consistent with pain in the lumbosacral region associated with bilateral hindlimb paresis were diagnosed using magnetic resonance imaging. Both cysts were solitary and associated with the L6-7 dorsal articulations; both the dogs had a transitional vertebra in the lumbosacral region. A third dog that was presented with progressive paraparesis localised to T3-L3 spinal cord segments and compression of the spinal cord at T13-L1 was diagnosed using myelography. A solitary multiloculated cyst was found at surgery. Decompressive surgery resulted in resolution of the clinical signs in all three dogs. Immunohistological findings indicated that one to two layers of vimentin-positive cells consistent with synovial origin lined the cysts.     

Topical (pour-on) ivermectin in the treatment of chronic generalized demodicosis in dogs

Twelve privately owned dogs with chronic generalized demodicosis were treated topically along the dorsal midline with 1.5 mg kg⁻¹ of 0.5% pour-on ivermectin for cattle three times per week for 3–6 months. All 12 dogs had a substantial reduction in clinical signs and in the number of Demodex canis mites found on skin scrapings. Only two dogs, however, became skin-scrapings negative after 3 and 5 months of treatment, respectively. In these two dogs treatment was prolonged for an additional 4 weeks past the negative scrapings. One dog relapsed 2 months after cessation of therapy; the other is still free of symptoms 1.5 years later. The cure rate, based on the lack of recurrence of clinical signs for 12 months after discontinuation of ivermectin administration, was 1 of 12 dogs (8%). Adverse reactions were not seen.     

Use of clomipramine in treatment of obsessive-compulsive disorder, separation anxiety and noise phobia in dogs: a preliminary, clinical study

OBJECTIVE: To evaluate the efficacy and tolerance of a treatment protocol for obsessive-compulsive disorder, separation anxiety and noise phobia in dogs. DESIGN: A study was undertaken to assess clinical responses in 24 dogs diagnosed with one or more of three behavioural disorders stated above to a treatment regimen that included clomipramine and behaviour modification. PROCEDURE: A detailed behavioural and clinical history was obtained for each dog. Obsessive-compulsive disorder was diagnosed in nine cases: primary presenting complaints were tail-chasing, shadow-chasing, circling and chewing; one case was diagnosed with concurrent separation anxiety. Separation anxiety was diagnosed in 14 cases: presenting complaints included destruction, vocalisation and escaping in the absence of the owner; four cases also exhibited noise phobia. The study also included one dog diagnosed with noise phobia only and another with inappropriate fear responses. Clomipramine was administered orally twice daily. The starting dose was 1 to 2 mg/kg bodyweight. The dose was increased incrementally to a maximum of 4 mg/kg if needed. A behaviour modification program was designed and the owner instructed on its implementation. Dogs continued medication for at least 1 month after clinical signs disappeared or were acceptably reduced, then withdrawal of medication was attempted by decreasing drug dosage at weekly intervals while behaviour modification continued. RESULTS: The presenting clinical sign was largely improved or disappeared in 16 dogs, 5 demonstrated slight to moderate improvement and the behaviour was unchanged in 3. Clomipramine withdrawal was attempted in nine cases: this was successful in five. CONCLUSION: Clomipramine was effective and well-tolerated in controlling signs of obsessive-compulsive disorder and/or separation anxiety and/or noise phobia in 16 of 24 assessable cases, when used in combination with behaviour modification, and improvement in clinical signs was noted in 5 others.     

Craniotomy with cystoperitoneal shunting for treatment of intracranial arachnoid cysts in dogs

Objective— To describe a technique of decompressive craniotomy with cystoperitoneal shunt (CPS) placement for treatment of canine intracranial arachnoid cyst (IAC), and to evaluate outcome in 4 dogs. Study Design— Retrospective study. Animals— Dogs (n=4) with IAC. Methods— Medical records of dogs diagnosed with IAC by magnetic resonance imaging (MRI; 3 dogs) or computed tomography (CT; 1 dog) were evaluated. All dogs had varying degrees of neurologic dysfunction before surgery. A combined lateral (rostrotentorial)/suboccipital craniotomy was performed sacrificing the transverse sinus on the operated side. The rostral (ventricular) end of a low‐pressure valve shunt (3.0 mm outer diameter, 7.0 cm length) was placed transversely into the cyst cavity; the distal end was placed in the peritoneal cavity. All dogs were rechecked at various intervals by ≥1 of the authors either directly, by telephone consultation with owners, or both. Three dogs were imaged postoperatively (CT–1 dog; MRI–1; ultrasonography–1). Results— Intraoperative complications were limited to excessive transverse sinus hemorrhage requiring blood transfusion in 1 dog. There were no postoperative complications. Clinical signs of neurologic dysfunction resolved in 3 dogs and improved substantially in 1 dog. The latter dog required long‐term, low‐dose corticosteroid therapy. No dogs required repeat surgery. Mean follow‐up time was 23.8 months (range, 12–43 months). Collapse of the intracranial cyst was verified in 3 dogs with repeat imaging. In 2 dogs, there was no evidence of the cyst on CT or MRI; in the third dog, a small amount of fluid was demonstrated rostral to the cerebellum on ultrasonography, but there was no identifiable cyst. In 1 dog, the rostral aspect of the shunt had shifted; however, this was not associated with any clinical deterioration. Conclusion— Craniotomy with CPS placement was well tolerated and resulted in sustained improvement or resolution of dysfunction. Cyst decompression was verified in 3 dogs that were re‐imaged. None of the patients required re‐operation. Excessive transverse sinus hemorrhage is a potential danger that may necessitate blood transfusion. Other IAC patients treated with this method will need to be evaluated to fully evaluate its effectiveness. Clinical Significance— Craniotomy with CPS placement may be an effective treatment method for dogs clinically affected with IAC.     

Autochthonous infections with Angiostrongylus vasorum in dogs in Switzerland and Germany

Angiostrongylus vasorum is endemic in foxes an other carnivores in the South and south East of France, Denmark and Great Britain. The reddish nematode is present in the Arteria pulmonalis and the right side of the heart and causes respiratory and cardiovascular symptoms. From 1999 to 2004, A. vasorum was diagnosed in 5 dogs from northern Switzerland, in 1 dog from southern Germany and in 3 dogs from south Ticino. Clinical signs in the affected dogs varied and ranged from cough, tachypnoea and dyspnoea to neurological symptoms in 2 of the dogs. Four dogs died and in 3 of the 4 dogs adults and larvae were found after digestion of formalin-fixed tissue. Diagnosis in the other 5 dogs was achieved by detecting the larvae coproscopically. Based on anamnestic data, these 9 dogs are probably autochthonous cases.     

Foramen magnum decompression with cranioplasty for treatment of caudal occipital malformation syndrome in dogs

Objectives— To describe a cranioplasty procedure used in conjunction with foramen magnum decompression (FMD) for the treatment of canine caudal occipital malformation syndrome (COMS), and to evaluate the clinical outcome. Study Design— Prospective clinical study. Animals— Dogs (n=21) with COMS diagnosed by magnetic resonance imaging (MRI). Methods— After FMD, titanium screws were placed around the perimeter of the foramen magnum defect and a skull plate fashioned from titanium mesh and polymethylmethacrylate was attached to the back of the skull, using the titanium screws as anchor posts. Follow‐up was obtained by direct examination by the authors, telephone interviews with owners and referring veterinarians, and a questionnaire sent to owners of surviving dogs designed to assign objective measures of response to surgical intervention. Surgical success was defined as improvement in ≥1 aspects of clinical dysfunction (e.g. scratching, pain) postoperatively. Owner‐assigned pre‐ and postoperative quality‐of‐life (QOL) scores (1–5) for surviving dogs were compared using a Wilcoxon's signed rank test for paired data (P≤.05). Results— No intraoperative complications occurred and postoperative complications were limited to transient worsening of a pre‐existing head tilt and ataxia in 1 dog, and the need for oral pain medication for 1–4 weeks in 3 dogs. Seventeen dogs (81%) had clinical improvement after surgery. Although clinical signs resolved in 1 dog, it died after being hit by a car, 5 months after surgery. One dog had no change in clinical signs; this patient's clinical signs were not severe and the owners had opted for surgery primarily to prevent progression of disease. Two dogs were euthanatized; 1 because of no improvement of severe clinical signs, and 1 because of sustained recurrence of apparent head and neck pain 7 months later. One dog required a dorsal laminectomy at a second site (C1/C2 vertebral level), 2 months later. Four dogs has transient “flare‐ups” of apparent head/neck pain 2–13 months later; all resolved with transient re‐institution of oral analgesic therapy. Further surgery at the FMD was not needed. Based on the returned questionnaires, there was an overall significant improvement in QOL scores. Conclusions— FMD with cranioplasty was well tolerated, with no intraoperative complications, and minor postoperative complications. Most dogs improved clinically, and none required further surgery at the original FMD site. Clinical Relevance— FMD with cranioplasty may be an effective surgical method of treating dogs with COMS and is well tolerated. Based on prior reports of FMD for this disorder, it appears that cranioplasty may reduce the rate of surgical failure caused by formation of compressive scar tissue at the FMD site in the short term. Results of this preliminary study support further evaluation of the cranioplasty procedure in a larger group of dogs over a more extended follow‐up period.     

Clinical signs,diagnosis and treatment of three dogs with angiostrongylosis in Ireland

: Infection with Angiostrongylus vasorum was diagnosed at necropsy on a dog that died from acute pulmonary haemorrhage, and on recovery of L1 larvae by Baermann examination of faeces from two dogs, one of which had abdominal pain and retroperitoneal haemorrhage, while the other had right-sided heart failure due to cor pulmonale. The presenting signs included syncope (one dog), exercise intolerance (two dogs), cough (two dogs), abdominal pain (one dog) and depression (one dog). One-stage prothrombin time and activated partial thromboplastin time were prolonged in two dogs, buccal mucosal bleeding time was prolonged in one dog and globulin was elevated in all three dogs. Two dogs were treated with fenbendazole and recovered.     

Hypercalcaemia in the dog: a study of 40 cases

Forty dogs referred to the University Department of Clinical Veterinary Medicine, Cambridge for medical and oncological conditions between 1985 and 1990 were found to be hypercalcaemia In 18 cases the primary or underlying condition was diagnosed as lymphoproliferative disease with multicentric lymphoma occurring most commonly. Ten dogs were suffering from hypoadrenocorticism (Addison's disease) and two had adenocarcinomas of the apocrine glands of the anal sac. In three dogs a clinical diagnosis of renal dysplasia was made, this diagnosis being confirmed at post mortem examination in one dog. In the remaining cases hypercalcaemia was associated with a primary lung tumour, a thymoma, an osteosarcoma with widespread skeletal metastases, primary hyperparathyroidism due to a parathyroid adenoma, chronic panniculitis, iatrogenic hypoadrenocorticism following mito-tane therapy (one case each] and, in a further case, no diagnosis was reached. The most common clinical signs were inappetence, polyuria/ polydipsia, weakness, vomiting, lethargy and depression. As a group, the dogs with lymphoproliferative disease had a significantly higher mean plasma calcium concentration (4-3 ± 0–7 vs 3–5 ± 0–4 mmol/litre), a significantly lower mean plasma inorganic phosphate concentration (1–5 ± 0–5 vs 2–4 ± 09 mmol/litre) and were significantly older (5-5 ± 2–4 vs 3-3 + 1–8 years) than the dogs with hypoadrenocorticism.     

RADIOGRAPHIC ASPECTS OF Pneumocystis carinii PNEUMONIA IN THE MINIATURE DACHSHUND

The thoracic radiographic changes of Pneumocystis carinii in 7 miniature Dachshunds were reviewed. The dogs were 7–12 months old and presented with polypnea, exercise intolerance and clinical signs suggestive of immune-incompetence. P. carinii pneumonia was diagnosed in all the dogs using transtracheal aspirate cytology and confirmed at postmortem in 3 dogs that died. Radiographically, diffuse pulmonary changes were present and varied from a mild interstitial and bronchial pattern to an alveolar pattern. Radiographic evidence of cor pulmonale was present in 1 dog. The most severe radiographic changes were seen in 2 of the dogs that died.