bluuebunny/crossref_metadata_2025 huggingface dataset:
Myelinolysis After Correction of Hyponatremia in Two Dogs
Authors: O'Brien Dennis P. , Kroll Robert A. , Johnson Gayle C. , Covert Steven J. , Nelson Martin J.
Published: March 2010

Two dogs developed delayed neurological deterioration after rapid correction of severe hyponatremia. Sequential magnetic resonance imaging showed the development of lesions in the thalamus. One dog was necropsied, and the lesions were characterized by myelinolysis with sparing of axons and neurons. The second dog gradually recovered with no detectable neurological deficits. The syndrome seems analogous to central pontine myelinolysis in human beings. Guidelines for correction of hyponatremia to prevent development of myelinolysis are given.
Alterations in Lipoprotein Profiles in Dogs With Lymphoma
Authors: Ogilvie Gregory K. , Ford Richard B. , Vail David M. , Walters Lisa M. , Salman M. D. , Babineau C. , Fettman Martin J.
Published: March 2010

After a 12‐hour fast, blood samples were obtained from 31 dogs with previously untreated lymphoma. Blood samples were also collected from 16 of these dogs after up to 5 treatments with doxorubicin (30 mg/m2intravenously every 3 weeks). All 16 dogs underwent complete remission. Five dogs were re‐evaluated after relapse and after overt signs of cancer cachexia had become clinically apparent. Samples were assayed for 8 quantitative parameters: total cholesterol (T‐CH) and total triglyceride (T‐TG) concentrations, and the concentration of cholesterol and triglyceride in each of the three major lipoprotein fractions, very‐low‐density lipoprotein (VLDL‐CH and VLDL‐TG), low‐density lipoprotein (LDL‐CH and LDL‐TG), and high‐density lipoprotein (HDL‐CH and HDL‐TG). The results were compared with those from 20 healthy control dogs of similar weight and age before and 3 weeks after being given one dose of doxorubicin (30 mg/m2intravenously). The administration of doxorubicin to control dogs resulted in a significant (P> .05) decrease in T‐CH, LDL‐CH, and HDL‐CH, as well as a significant increase in VLOL‐TG and HDL‐TG. When compared with untreated controls, untreated dogs with lymphoma had significantly higher concentrations of VLDL‐CH, T‐TG, VLDL‐TG, LDL‐TG, and HDL‐TG, and significantly lower concentrations of HDL‐CH. HDL‐TG and VLDL‐TG concentrations from dogs with lymphoma were significantly increased above pretreatment values after relapse and development of overt signs of cancer cachexia. Dogs in remission that were evaluated after one dose of doxorubicin had significantly higher concentrations of T‐CH, VLDL‐CH, T‐TG, and LDL‐TG when compared with controls that were evaluated after an identical dose of doxorubicin. HDL‐TG increased significantly over pretreatment values in dogs with lymphoma after doxorubicin therapy. These results suggest that dogs with lymphoma have significant alterations in lipid profiles, and with the possible exception of HDL‐CH, these abnormalities do not normalize when clinical remission is obtained.
Ammonia Metabolism and the Urea Cycle: Function and Clinical Implications
Authors: Dimski Donna S.
Published: March 2010

Disposal of waste products accumulated during metabolic processes is integral to the health of any living organism. Disposal of excess nitrogen and ammonia is no exception. Although nitrogen is essential for growth and maintenance in animals, an excess of some nitrogenous compounds can quickly lead to toxicity and death. Because of the correlation between ammonia accumulation and clinical disease, it is important for veterinary clinicians to understand the physiological mechanisms used to dispose of nitrogen and ammonia. Therefore, the purposes of this article are to review ammonia metabolism, the urea cycle, and the clinical implications of urea cycle dysfunction in diseases of companion animals.
Identification of an Intrinsic Platelet Function Defect in Spitz Dogs
Authors: Boudreaux Mary K. , Crager Cynthia , Dillon A.R. , Stanz Kimberly , Toivio‐Kinnucan Maria
Published: March 2010

A recently identified intrinsic platelet function defect in 2 Spitz dogs is described. Both affected dogs had a history of chronic intermittent bleeding primarily from the nasal, oral, and gastrointestinal mucosa. Platelet aggregation in response to adenosine diphosphate (ADP), collagen, and platelet activating factor (PAF) was absent; however, platelet shape change did occur. Platelets aggregated in response to gamma thrombin, although a delayed onset and a reduced velocity of aggregation were present. Platelet 14C‐serotonin release was diminished in response to collagen and PAF. Glycoprotein Illa was detected on the surface of platelets by flow cytometry. Platelets were morphologically normal under light and electron microscopy. Two male Spitz dogs, related to one of the affected dogs, did not have a bleeding diathesis. Collagen‐induced platelet aggregation, however, was diminished in these 2 dogs. This platelet defect most closely resembles the defect described in Basset hounds.
Cerebellar Purkinje's Cell Degeneration and Coat Color Dilution in a Family of Rhodesian Ridgeback Dogs
Authors: Chieffo Carla , Stalis Ilse H. , Van Winkle Thomas J. , Haskins Mark E. , Patterson Donald F.
Published: March 2010

A syndrome of cerebellar Purkinje's cell degeneration and coat color dilution was diagnosed in a family of Rhodesian Ridgeback dogs. One male and 1 female from the same litter and 1 female from a different litter were evaluated for growth retardation, inability to ambulate, and progressive ataxia. On physical examination, lateral recumbency, severe ataxia, tremors, and diluted coat color were identified. Littermates with nondiluted coat color were neurologically normal. Results of routine laboratory tests, urine metabolic screenings, and karyotype analyses were normal. Histopathologic abnormalities at necropsy included cerebellar Purkinje's cell degeneration, reduced granular cell layer thickness, and uneven distribution of macromelanosomes within hair shafts. Pedigree analysis suggested an autosomal recessive mode of inheritance. This is the first description of a genetic syndrome affecting the central nervous system and associated with coat color dilution in dogs.
Neurological Manifestations of Niemann‐Pick Disease Type C in Cats
Authors: Muñana Karen R. , Luttgen Patricia J. , Thrall Mary Anna , Mitchell Thomas W. , Wenger David A.
Published: March 2010

Seven Domestic shorthair cats with a lysosomal storage disorder analogous to human Niemann‐Pick disease type C, from a breeding colony were studied to characterize the neurological manifestations of this disorder. Affected cats were identified by means of liver biopsies at 4 to 6 weeks of age. Neurological examinations were performed at 2 week intervals from the onset of clinical signs. All cats displayed signs referrable to the cerebellum, with a subtle intention tremor noticed initially at 8 to 12 weeks of age; the disease was rapidly progressive. The tremor became more pronounced, menace response was lost, and severe dysmetria and ataxia developed. Three cats also had signs referrable to other areas of the central nervous system. Cats died or were euthanized between 12 and 43 weeks of age. Pathological findings included accumulation of substrate within neurons throughout the central nervous system, and axonal spheroid formation. The clinical and pathological findings in these cats are comparable to those in the human form of the disease.
Tetanus in the Horse: A Review of 20 Cases (1970 to 1990)
Authors: Green Sherril L. , Little Christopher B. , Baird John D. , Tremblay Robert R. M. , Smith‐Maxie Laura L.
Published: March 2010

The case records of 20 horses with tetanus referred to the Ontario Veterinary College‐Veterinary Teaching Hospital between 1970 and 1990 were reviewed. The fatality rate was 75%. There was a strong association with previous vaccination and survival (P= .03). Most of the animals had been injured an average of 9 days (range 2 to 21 days) prior to development of clinical signs. Hyperesthesia and prolapse of the third eyelid were the most common clinical signs. Treatment regimens varied during hospitalization; however, all horses received parenteral penicillin, tranquilizers, tetanus toxoid, and antitoxin. Five of the nonsurviving animals were given intrathecal tetanus antitoxin. One animal had seizures as a complication of intrathecal treatment. The prognosis was best for horses that (1) had been vaccinated prior to the injury, (2) responded to the phenothiazine tranquilizers, and (3) did not rapidly (over 24 to 48 hours) become recumbent. Considering the species susceptibility, potential for contaminated wounds, and the increased survival of vaccinated horses, yearly revaccination is recommended.
Pheochromocytoma in 50 Dogs
Authors: Gilson Stephen D. , Withrow Stephen J. , Wheeler Steven L. , Twedt David C.
Published: March 2010

Fifty dogs with pheochromocytoma were identified in a retrospective study of a 9‐year period. For 24 of 50 dogs (48%), the tumor was an incidental finding during necropsy or surgery. Presenting signs were referrable to the nervous system in 7 of the 26 symptomatic dogs (27%); were referrable to the cardiopulmonary system in 7 of 26 dogs (27%); or were nonspecific, reflecting general systemic disease, in 17 of 26 dogs (65%). Abnormal clinical findings were highly varied but were also generally referrable to the cardiopulmonary and nervous systems. Six of 7 dogs (86%) evaluated were hypertensive (systolic range, 164 to 325 mm Hg; diastolic range, 110 to 198 mm Hg). Serum biochemical findings were nonspecific, although 11 of 39 dogs (28%) were hypercholesterolemia Abdominal fluid samples were analyzed in 6 dogs; 3 were nondiagnostic, and 3 were interpreted as lymphosarcoma. The imaging studies that were of most value included abdominal radiographs (mass identified in 9 of 16 dogs [56%]), caudal vena caval angiography (tumor thrombus correctly diagnosed in 4 of 7 dogs [57%]), and abdominal ultrasonography (mass seen in 5 of 6 dogs [83%] and tumor thrombus seen in 3 of 5 dogs [60%]). Local tumor invasion was present in 26 of 50 dogs (52%), regional lymph node mestatases in 6 of 50 dogs (12%), and distant metastases in 12 of 50 dogs (24%). Cause of death was tumor‐related in 19 of 50 dogs (38%) and non‐tumor related in 28 of 50 dogs (54%).
Monoclonal Gammopathy in a Dog With Visceral Leishmaniasis
Authors: Font Artur , Closa Jose M. , Mascort Joan
Published: March 2010

One dog with visceral leishmaniasis associated with monoclonal gammopathy is described. Most dogs with visceral leishmaniasis present with hyperproteinemia due to a polyclonal gammopathy, but the possibility of monoclonal gammopathy must be considered. Because dogs accompany their owners when they travel, the diagnosis of leishmaniasis should be considered if an animal with monoclonal gammopathy has visited an area where the disease is endemic. The observation ofLeishmaniain the macrophages of a bone marrow, lymph node smear, or skin biopsy specimen is diagnostic.
Treatment of Tumor‐Bearing Dogs With Actinomycin D
Authors: Hammer Alan S. , Couto C. Guillermo , Ayl Rodney D. , Shank Karen A.
Published: March 2010

Fifty dogs with advanced malignancies were treated with actinomycin D at doses ranging from 0.5 to 1.1 mg/m2every 3 weeks. The greatest number of responses was noted in dogs with lymphoma, including dogs that had received prior chemotherapy. Other responding tumor types included anal sac adenocarcinoma, perianal adenocarcinoma, squamous cell carcinoma, thyroid carcinoma, and transitional cell carcinoma. The median time to maximum response for dogs with lymphoma was 7 days, with a median duration of 42 days. Gastrointestinal toxicity was the most frequently observed side effect. A dose of 0.6 to 0.7 mg/m2appears to be appropriate for treating various malignancies in dogs.
Unexpected Neurotoxicity in Dogs Receiving a Cyclophosphamide, Dactinomycin, and 5‐Fluorouracil Chemotherapy Protocol
Authors: Hammer Alan S. , Carothers Marcia A. , Harris Cheryl L. , O'Keefe Deborah A. , Ayl Rodney D. , Peterson Janet L. , Shank Karen A. , Couto C. Guillermo
Published: March 2010

An inexpensive combination chemotherapy protocol containing cyclophosphamide, dactinomycin, and 5‐fluorouracil was evaluated in dogs with carcinomas. Fifteen dogs were entered in this study, and there were 1 complete response and 2 partial responses among 12 evaluable dogs. However, 6 of 15 dogs (40%) developed neurotoxicity. The neurotoxicity of this protocol was compared with a previous 5‐fluorouracil‐containing protocol and found to be significantly higher. Due to the unacceptably high rate of neurotoxicity, this protocol cannot be recommended for use in dogs with cancer.
Evaluation Of An Additive Solution For Preservation Of Canine Red Blood Cells
Authors: Wardrop K. Jane , Owen Tina J. , Meyers Kenneth M.
Published: March 2010

The effect of an additive preservative solution on canine red blood cell posttransfusion viability (PTV) and on selected canine red blood cell biochemical parameters was studied. One unit (450 mL) of blood was collected from 6 clinically normal dogs into the anticoagulant citrate phosphate dextrose, centrifuged, and the plasma removed. The red blood cells were then suspended in 100 mL of a saline, adenine, dextrose, and mannitol solution and stored at 4°C. Aliquots were removed for study at 1, 10, 20, 30, 37, and 44 days. The 24‐hour PTV of autologous red blood cells was determined using a sodium chromate (61Cr) label. Red blood cell concentrations of 2,3‐diphosphoglycerate (2,3‐DPG), adenosine‐5'‐triphosphate (ATP), and pH were also determined. Canine red blood cell PTV, pH, ATP, and 2,3‐DPG concentrations decreased during storage (P< .05). The PTV decreased from 94% using day 1 red blood cells to 80% and 75% using day 37 and day 44 red blood cells, respectively (P< .05). Although the mean PTV of the day 44 stored units equaled the Food and Drug Administration (FDA) minimum standard for human red blood cells, the PTV was substandard in 75% of the day 44 units. The FDA standard was exceeded in 83% of the day 37 units. It was concluded that 37‐day‐old canine red blood cells preserved with a saline, adenine, dextrose, and mannitol solution are of acceptable quality for transfusion.
0–7–21 Radiation Therapy for the Treatment of Canine Oral Melanoma
Authors: Bateman Karen E. , Catton Pamela A. , Pennock Paul W. , Kruth Stephen A.
Published: March 2010

Eighteen dogs with malignant melanoma of the oral cavity were treated with high‐dose per fraction (0–7–21) radiation therapy. Eight hundred cGy was administered on days 0, 7, and 21 for a total dose of 2,400 cGy in 3 weeks. Of 17 dogs evaluated, 9 (53%) had a complete remission and 5 (30%) achieved a partial remission with an overall response rate of 83%. Local failure occurred in 2 of the 9 dogs where a complete response was initially observed. One dog died of intercurrent disease, and one died of metastatic disease without evidence of local recurrence. Five dogs are alive and free of disease 9 to nineteen months from the initiation of therapy. The 0–7–21 protocol was well‐tolerated, and acute radiation reactions were low‐grade and limited to the skin. The results of this study demonstrate that oral melanomas in dogs are responsive to radiation. 0–7–21 radiation therapy offers a viable alternative to radical excision, especially when tumor volume or location would require cosmetically or functionally debilitating surgery.
Quantitative Aspects of Thyroid Scintigraphy With Pertechnetate (99mTcO4) in Cats
Authors: Nap Ariana M.P. , Pollak Yvonne W.E.A. , van den Brom Walter E. , Rijnberk Ad
Published: March 2010

Thyroidal99mTcO4(pertechnetate) uptake percentages were determined in unanesthetized euthyroid (n = 13) and hyperthyroid (n = 18) cats. Maximal uptakes were observed 60 minutes after IV injection of the radionuclide and ranged from 0.3 to 3.9% of the dose in euthyroid cats (median 2.23%) and from 5.2% to 23.9% of the dose in hyperthyroid cats (median 14.8%) (P< .05). There were no overlaps in pertechnetate uptake percentages during any of the intervals evaluated. It is concluded that the optimal time for visualization of the thyroid by99mTcO4‐scanning is 60 minutes after IV injection of the radionuclide. Calculation of the percentage uptake is of additional diagnostic value.
Brainstem Auditory‐Evoked Potentials and Neuropatholgic Correlates in 26 Dogs With Brain Tumors
Authors: Fischer A. , Obermaier G.
Published: March 2010

Brainstem auditory—evoked potentials (BAEPs) were recorded from 26 dogs with intracranial neoplasia. The tumors were grouped according to their neuroanatomic location. Normal BAEPs were recorded from 12 dogs with cerebral (6/7), diencephalic (4/4), cerebellar (1/1), and multifocal tumors (1/5). Abnormal BAEPs were recorded from 14 dogs with cerebral (1/7), cerebellar/brainstem (4/ 4), brainstem (5/5), and multifocal tumors (4/5). Analysis of the multifocal neoplasms showed that alterations of BAEPs correlated with the degree of brainstem involvement. Overall, 13 of the 14 dogs with abnormal BAEPs had tumors involving the brainstem. The changes of the BAEP correlated with the extrinsic or intrinsic location of the tumor relative to the brainstem. The BAEP reflected the right, left, or median location of the tumor in 7 of the 14 abnormal recordings. In 1 dog, the BAEP was abnormal contralateral to the tumor side. A peripheral hearing disorder was excluded in most dogs based on the presence of peak 1.
Hyperlipemia in 9 Miniature Horses and Miniature Donkeys
Authors: Moore Bonnie Rush , Abood Sarah K. , Hinchcliff Kenneth W.
Published: March 2010

The medical records from 9 consecutive miniature horses (n = 5) and miniature donkeys (n = 4) with hyperlipemia (serum triglyceride concentration > 500 mg/dL) were reviewed. In all cases, hyperlipemia was a secondary complication of a primary systemic disease including septicemia, colitis, parasitism, esophageal obstruction, gastric impaction and rupture, fecalith, and pituitary adenoma. Therapy consisted of specific treatment for the primary disease, supportive care, and nutritional support. The mean time for resolution of hyperlipemia in cases requiring nutritional support (n = 6) was 7 days, and the duration of nutritional support in surviving patients was 11.7 days. Seven of 9 patients survived. The primary disease resulted in death in 2 patients. Enteral feeding with commercially prepared low residue diets and treatment of the primary disease was successful in reversing hyperlipemia in 5 of 6 surviving patients that required nutritional support. Parenteral administration of a glucose‐based (non‐lipid) solution was successful in resolving hyperlipemia in 1 patient.
0–7–21 Radiation Therapy for the Palliation of Advanced Cancer in Dogs
Authors: Bateman Karen E. , Catton Pamela A. , Pennock Paul W. , Kruth Stephen A.
Published: March 2010

The 0–7–21 radiation therapy protocol was investigated as a palliative treatment in dogs with advanced malignancies. Twenty‐four dogs with a variety of tumor types were irradiated using 800 cGy fractions given on days 0, 7, and 21. Twenty‐three dogs were evaluated. Palliative response was assessed using a quality of life instrument developed for veterinary use. This pain score was based on owner response to questions regarding analgesic requirement, activity level, appetite, and degree of lameness in the affected dogs. Seventeen (74%) of the 23 dogs experienced complete pain relief, and 3 (13%) obtained partial relief. Of the 17 dogs that achieved a complete response, pain recurred in 8 at a median time of 70 days. Six dogs were alive and free of pain up to 557 days after irradiation. The 0–7–21 protocol was well tolerated; pain relief occurred quickly, and acute radiation reactions were negligible.
Itraconazole for the Treatment of Histoplasmosis in Cats
Authors: Hodges Ronald D. , Legendre Alfred M. , Adams Larry G. , Willard Michael D. , Pitts Roger P. , Monce Kevin , Needels Conya C. , Ward Heidi
Published: March 2010

Eight cats with histoplasmosis were treated with itraconazole at 5 mg/kg per dose PO bid. There were multiple sites of infection, and 2 of the cats had hypercalcemia that was attributed to the histoplasmosis. All 8 cats were eventually cured, but 2 cats experienced recurrences of disease after completion of therapy, requiring 2 to 3 additional months of itraconazole. There were no clinically relevant adverse effects during treatment. Although a limited number of cats were treated, the study suggests that itraconazole is a well‐tolerated and effective drug for the treatment of histoplasmosis in the cat.
Serum Bile Acid Concentrations in Dairy Cattle With Hepatic Lipidosis
Authors: Garry Franklyn B. , Fettman Martin J. , Curtis Charles R. , Smith John A.
Published: March 2010

This study was designed to evaluate serum bile acid measurements as indicatory, of liver function and/or hepatic fat infiltration in dairy cattle. Serum bile acid concentrations were measured in healthy dairy cattle at different stages of lactation after fasting or feeding. Bile acid concentrations were compared with liver fat content and sulfobromophthalein (BSP) half‐life (T 1/2). Serum bile acid concentrations were higher in cows in early lactation and with higher daily milk production. Compared with prefasting values, bile acid concentrations were decreased at 8,14, and 24 hours of fasting. Blood samples from fed cows at 1 ‐ to 2‐hour intervals had wide and inconsistent variations in bile acid concentration. Because serum bile acids correlated well with BSP T 1/2, it is suggested that both measurements evaluate a similar aspect of liver function. Neither bile acids nor BSP T I correlated with differences in liver fat content among cows. Because of large variability in serum bile acid concentrations in fed cows and the lack of correlation of measured values with liver fat content, bile acid determinations do not appear useful for showing changes in hepatic function in fed cows with subclinical hepatic lipidosis nor serve as a screening test for this condition.
Plasma Taurine Concentrations in Normal Dogs and in Dogs With Heart Disease
Authors: Kramer George A. , Kittleson Mark D. , Fox Philip R. , Lewis Julia , Pion Paul D.
Published: March 2010

Plasma taurine concentrations were determined in 76 dogs with dilated cardiomyopathy (DCM), 28 dogs with acquired valvular disease (AVD), and 47 normal (control) dogs. The data were collected at 2 referral centers. The Animal Medical Center, New York, NY (AMC), and the University of California, Davis (UCD), and the studies were conducted independently. Different anticoagulants (sodium citrate at AMC and lithium heparin at UCD) were used to collect the plasma samples. Paired analysis of samples showed a significant difference in plasma taurine concentrations, depending on the anticoagulant used. Consequently, results from each clinic were analyzed separately. Plasma taurine concentrations were significantly higher in dogs with AVD (median, 133 nmol/mL; range, 25 to 229 nmol/mL) than in control dogs (median, 63 nmol/mL; range 44 to 224 nmol/mL) and dogs with DCM (median, 72 nmol/mL; range, 1 to 247 nmol/mL) at AMC (P= .001). The number of dogs with AVD at UCD was too small to draw meaningful conclusions. At UCD, the median plasma taurine concentration was 98 nmol/mL (range, 28–169 nmol/mL) in dogs with AVD, 75 nmol/mL (range, 0.1–184 nmol/mL) in dogs with DCM, and 88 nmol/mL (range 52–180 nmol/mL) in control dogs. There were no significant differences in plasma taurine concentrations between dogs with DCM and the control dogs at either hospital. Congestive heart failure and administration of cardiac medication had no significant effect on plasma taurine concentrations. Plasma taurine concentration was low (<25 nmol/mL) in 17% (13/76) of the dogs with DCM. Seven of the 13 dogs with low plasma taurine concentrations were Cocker Spaniels or Golden Retrievers. It was concluded that most dogs with DCM do not have low plasma taurine concentrations. However, certain breeds or individual dogs may have low plasma taurine concentrations in association with DCM. Whether this association is causal or not is unknown. The significance of the high plasma taurine concentrations in dogs with AVD is also unknown.
Anti‐Liver Membrane Protein Antibodies in Dogs With Chronic Hepatitis
Authors: Weiss Douglas J. , Armstrong P. Jane , Mruthyunjaya Asha
Published: March 2010

Serum from 21 dogs with chronic hepatitis was evaluated for anti‐liver membrane protein (anti‐LMP) antibodies by an enzyme‐linked immunosorbent assay. Ten of the 21 dogs had anti‐LMP antibody concentrations greater than 2 SD above the mean value for the 10 healthy control dogs; titers ranged from 1:40 to greater than 1:1,600. Anti‐LMP—positive dogs were not restricted by breed, had higher alanine amino transferase activity and total bilirubin concentration, and more severe liver lesions when compared with anti‐LMP—negative dogs. This study provided evidence of humoral autoantibodies in dogs with chronic hepatitis, but it did not determine if the autoantibodies were primary or secondary.
Equine Melanocytic Tumors: A Retrospective Study of 53 Horses (1988 to 1991)
Authors: Valentine Beth A.
Published: March 2010

A study of 57 cutaneous melanocytic tumors from 53 horses revealed 4 distinct clinical syndromes: melanocytic nevus, dermal melanoma, dermal melanomatosis, and anaplastic malignant melanoma. Melanocytic nevus and anaplastic melanoma each had histopathologic features that distinguished them from dermal melanoma and dermal melanomatosis. Dermal melanoma and dermal melanomatosis were histologically similar but could be differentiated by their clinical features. Melanocytic nevi were diagnosed in 29 horses with an average age of 5 years; they were solitary, superficial masses that occurred in both grey and nongrey horses, and in which surgical excision was generally curative. Dermal melanomas were diagnosed in 20 horses with an average age of 13 years; all horses of known coat color were grey. Eight horses with an average age of 7 years had 1 or 2 discrete dermal melanomas. Follow‐up information was available for 6 horses; metastases occurred in 2 horses, and surgical excision was apparently curative in 4 horses. Dermal melanomatosis was diagnosed in 12 grey horses with an average age of 17 years; all 6 of these horses evaluated had internal metastases. In 2 aged nongrey horses with anaplastic malignant melanoma, the tumors metastasized within 1 year of diagnosis. Two tumors with features of both melanocytic nevus and dermal melanoma remained unclassified.
Diagnosis of Inflammatory and Infectious Diseases of the Central Nervous System in Dogs: A Retrospective Study
Authors: Tipold Andrea
Published: March 2010

The medical records of 220 dogs with inflammatory/infectious diseases of the central nervous system (CNS) were retrospectively examined. The aims of the study were to determine if clinical and clinicopathologic data (not including biopsy or necropsy examination) could distinguish inflammatory CNS diseases from diseases of other types, and to search for criteria allowing differentiation of specific inflammatory diseases. The signalment, historical findings, extraneural and neurological signs, and the lesion site contributed marginally to a specific diagnosis. Multifocal signs were only noticed in one third of the dogs with inflammatory/infectious diseases. Particular neurological abnormalities were more frequent in certain diseases than in others (eg, myoclonus was frequent in dogs with distemper, but it was also found in those with other meningoencephalomyelitides). Hematologic findings contributed to the diagnosis in certain conditions (eg, canine distemper encephalitis, protozoal encephalomyelitis, steroid‐responsive meningitis‐arteritis). Cerebrospinal fluid examinations, including immunoglobulin G index and cytology were useful to separate meningoencephalomyelitides from the other CNS diseases and to distinguish certain conditions from others. In most cases a specific diagnosis depended on a combination of clinical signs and ancillary diagnostic aids. Still, a specific diagnosis remained very difficult, if not impossible, in at least one third of the dogs.
Activation of the Renin‐Angiotensin System in Dogs With Asymptomatic and Mildly Symptomatic Mitral Valvular Insufficiency
Authors: Pedersen Henrik D. , Koch Jørgen , Poulsen Knud , Jensen Asger L. , Flagstad Annette
Published: March 2010

The renin‐angiotensin system has important pathophysiologic implications in the development of congestive heart failure. The activity of the renin‐angiotensin system early in the course of heart disease and heart failure in dogs was evaluated by measuring the plasma renin activity (PRA) and plasma aldosterone concentration (PAC) in 18 Cavalier King Charles Spaniels with asymptomatic or mildly symptomatic mitral valvular insufficiency, and in 18 healthy Cavalier King Charles Spaniels. All dogs were unmedicated and had no other diseases. The PRA was high in the dogs with mitral valvular insufficiency (median 3.44 ng/mL/h, interquartile interval 2.59 to 8.66 ng/mL/h) compared with the controls (median 2.51 ng/mL/h, interquartile interval 1.44 to 3.58 ng/mL/h). The PAC was also higher in the dogs with mitral insufficiency (median 53 pg/mL, interquartile interval 33 to 138 pg/mL) than in the control group (median 27 pg/mL, interquartile interval 11.5 to 54 pg/mL). However, there was considerable overlap between the 2 groups in both PRA and PAC. It was concluded from these data that there is early activation of the renin‐angiotensin system in some Cavalier King Charles Spaniels with mitral valvular insufficiency. Further prospective studies are needed to determine if early intervention with angiotensin‐converting enzyme inhibitors will be valuable in this group of patients.
Endoscopically Guided Balloon Dilatation of Benign Esophageal Strictures in 6 Cats and 7 Dogs
Authors: Harai Brenda H. , Johnson Susan E. , Sherding Robert G.
Published: March 2010

Benign esophageal strictures in 6 cats and 7 dogs were treated with endoscopically guided balloon dilatation. Six of 13 had a history of anesthesia within 3 weeks prior to the onset of signs; 8 animals had a single stricture, and 5 had multiple strictures, for a total of 19 strictures. Four of the 19 strictures were in the upper esophagus, 11 were in the middle esophagus, and 4 were in the lower esophagus. The luminal diameters ranged from 1 to 18 mm, with a mean of 5.1 mm. Twelve animals survived the immediate postprocedure period and had a total of 50 dilatation procedures performed; the mean number of procedures per animal was 4.2 (range, 2 to 8). Complications included mild bleeding and tearing (11 of 13), moderate bleeding (1 of 13), and esophageal perforation (1 of 13). The cat with the perforation was subsequently euthanized. Follow‐up information was available on the 12 remaining animals; 9 were known to be alive 6 to 59 months (mean, 28.2 months) after dilatation. Two were euthanized, 1 for persistence of signs and the other for unrelated causes. One animal died of possible aspiration pneumonia. Three of 13 animals had complete and 9 had partial resolution of signs. Of the 9 animals with partial resolution, 7 were substantially better with dietary modification, 1 was moderately better, and 1 had minimal improvement. Eleven of 13 animals (85%) had a successful outcome with moderate to complete resolution of signs. Thus, it is concluded that endoscopically guided balloon dilatation is an effective and relatively safe treatment for benign esophageal strictures in dogs and cats.
Echocardiographic Detection of Flail Left Atrioventricular Valve Cusp From Ruptured Chordae Tendineae in 4 Dogs
Authors: Jacobs Gilbert J. , Calvert Clay A. , Mahaffey Mary B. , Hall D. Greg
Published: March 2010

Echocardiography was used to identify a flail left atrioventricular valve cusp caused by ruptured chordae tendineae in each of 4 dogs; two‐dimensional echocardiography was superior to M‐mode echocardiography in identifying the flail cusps. The following findings on two‐dimensional imaging were characteristic: the tip of the flail cusp extended beyond the line of left atrioventricular valve cusp closure and pointed toward the left atrium in systole; the tip was thrust into the left ventricle, and then toward the left ventricular outflow tract in diastole, forming a convex surface to the cusp, which faced toward the left ventricle. The flail motion of the left atrioventricular valve cusp was best observed in the right parasternal long axis or left apical four‐chamber views, in a plane parallel to the long axis of the left ventricle and left atrium. Rupture of chordae tendineae leading to flail cusp was attributed to chronic valve degeneration (endocardiosis) in all 4 dogs. Echocardiographic or clinical diagnoses were confirmed by postmortem gross and microscopic studies in all dogs.
Central Diabetes Insipidus in a Dog With a Pro‐Opiomelanocortin‐Producing Pituitary Tumor ot Causing Hyperadrenocorticism
Authors: Goossens Mariëlle M.C. , Rijnberk Ad , Mol Jan A. , Wolfswinkel Jeannette , Voorhout George
Published: March 2010

Central diabetes insipidus was diagnosed by vasopressin measurements during hypertonic stimulation in a 9‐year‐old male giant Schnauzer with polyuria and polydipsia. The impaired release of vasopressin was believed to be caused by a large pituitary tumor, which was visualized by computed tomography. Studies of the function of the anterior lobe and the pars intermedia of the pituitary gland were conducted, and high concentrations of ACTH and α‐melanotrophic hormone (α‐MSH) were found without concomitant hyperadrenocorticism. Studies of the molecular size of the immunoreactive ACTH in plasma by gel filtration revealed that most of the circulating immunoreactivity was not ACTH but its precursor pro‐opiomelanocortin (POMC) and low‐molecular‐weight POMC‐derived peptides. The pituitary tumor of this dog probably originated from melanotrophic cells of the pars intermedia. The sensitivity of the pituitary‐adrenocortical system for the suppressive effect of dexamethasone was unaffected.
The Effect of Misoprostol on Aspirin‐Induced Gastroduodenal Lesions in Dogs
Authors: Johnston Spencer A. , Leib Michael S. , Forrester S. Dru , Marini Michele
Published: March 2010

Misoprostol, a synthetic prostaglandin E1, analog, is effective in treating and preventing nonsteroidal antiin‐flammatory drug (NSAID)‐induced gastrointestinal lesions in humans. The effectiveness of misoprostol in preventing aspirin‐induced gastroduodenal injury was studied in 3 groups of 6 adult mixed breed dogs. Group I received 3 μg/kg misoprostol PO tid. Group II received 3 μg/kg misoprostol PO tid and 35 mg/kg aspirin PO tid. Group III received 35 mg/kg aspirin PO tid. Endoscopy was performed on days 0, 5, 14, and 30. Five regions of the upper gastrointestinal tract were qualitatively scored from 1 to 12 based on the presence of submucosal hemorrhage, erosion, or ulceration, with ulceration receiving a higher numerical score than submucosal hemorrhage. A total score was assigned based on the sum of the scores from all regions. Comparisons among groups on each day were performed using the Kruskal‐Wallis test. Differences within a group among different time periods were determined using appropriate multiple comparisons. Significant difference in mean gastroduodenal lesion score was found among all groups at 5, 14, and 30 days. Mean total score on days 5, 14, and 30 were as follows: group 1,5.0,5.2, 9.0; group II, 12.0, 12.7, 16.2; and group III, 26.0, 23.8, 21.5, respectively. Significant differences within a group among different time periods were found from days 0 to 5 in groups I and II, and from days 14 to 30 in group I. It was concluded that misoprostol effectively decreased endoscopically detectable mucosal lesions in dogs given aspirin.
Orthodromic Reciprocating Tachycardia and Heart Failure in a Dog With a Concealed Posteroseptal Accessory Pathway
Authors: Atkins Clarke E. , Kanter Ronald , Wright Kathy , Saba Ziad , Baty Catherine , Swanson Cliff , Bai Stephen , Keene Bruce W.
Published: March 2010

A 4‐month‐old male Labrador Retriever was presented for recurrent bouts of pulmonary edema associated with tachycardia. Initial physical examination and echocardiography were unremarkable, and the electrocardiogram revealed only an intraventricular conduction disturbance. Subsequent recordings showed paroxysmal supraventricular tachycardia (SVT) (340 beats/min), which consistently produced pulmonary edema. The supraventricular tachycardia was unresponsive to adenosine, esmolol, and propranolol; was variably and transiently responsive to various vagal maneuvers and precordial thumps; and was always responsive to IV diltiazem. Multiple life‐threatening episodes of SVT occurred, however, despite the chronic administration of oral diltiazem, propranolol, and procainamide. Diastolic cardiac dysfunction was documented by Doppler echocardiography and was thought to contribute to the development of pulmonary edema. A subsequent electrophysiologic study confirmed the presence of an atrioventricular posteroseptal accessory pathway that participated in orthodromic reciprocating tachycardia. This pathway was determined to conduct only in the retrograde direction (“concealed accessory pathway”). Intraoperative IV procainamide titration terminated the arrhythmia, which could not be reinduced when procainamide blood concentration approximated 20 μg/dL. Increasing the oral procainamide dose to achieve such plasma concentrations was successful in eliminating orthodromic reciprocating tachycardia, preventing heart failure, and returning Doppler indices of diastolic function to normal.
Treatment of Atrial Fibrillation in Horses: New Perspectives
Authors: Reef Virginia B. , Reimer Johanna M. , Spencer Pamela A.
Published: March 2010

Forty‐one horses were treated for atrial fibrillation (AF) with 22 mg/kg quinidine sulfate via nasogastric tube every 2 hours until conversion to sinus rhythm, a cumulative dose of 88 to 132 mg/kg had been administered in 2‐hour increments, or the horse had adverse or toxic effects from the drug. Treatment intervals were prolonged to every 6 hours if conversion had not occurred. Digoxin was administered before treatment if the horse had a fractional shortening ≤ 27% (3 horses), was prone to tachycardia (resting heart rate ≥ 60 beats/min) (1 horse), or had a previous history of sustained tachycardia of over 100 beats/min during prior conversion (3 horses). Digoxin was administered during day 1 of quinidine sulfate treatment if the horse developed a sustained tachycardia of over 100 beats/min during treatment (11 horses) or on day 2 if conversion had not occurred (7 horses). Plasma quinidine concentrations within 1 hour of conversion of AF to sinus rhythm ranged from 1.7 to 7.5 μg/mL (mean, 4.05± 1.6) and ranged from 1.7 to 4.7 μg/mL in 97% of horses. Most horses (92%) with plasma quinidine concentrations > 5 μg/mL exhibited an adverse or toxic effect of quinidine sulfate (clinical or electrocardiographic). There was no statistical association between plasma quinidine concentrations and sustained tachycardia (> 100 beats/min), diarrhea, or colic. Ataxia and upper respiratory tract stridor were significantly associated with plasma quinidine concentrations. In most instances (98%) conversion did not occur while toxic or adverse effects of quinidine sulfate were present or when plasma quinidine concentrations were > 5 μg/mL.
Endothelin Concentration in Plasma of Healthy Dogs and Dogs With Congestive Heart Failure, Renal Failure, Diabetes Mellitus, and Hyperadrenocorticism
Authors: Vollmar Angelika M. , Preusser Ursula , Gerbes AIexander L. , Kraft Wilfried , Schulz Rüdiger
Published: March 2010

Plasma concentrations of endothelin (ET)‐1 and ‐3 were determined simultaneously in dogs with various pathophysiological conditions, because these peptides may display different pharmacological profiles. The study pays special attention to the characterization of plasma ET immunoreactivity (ET‐IR), using high‐pressure liquid chromatography (HPLC) analysis with off‐line detection by radioimmunoassay (RIA). In most sick dogs evaluated total plasma ET‐1‐IR concentration did not differ from that of healthy dogs. However, HPLC analysis of their total plasma ET‐1 ‐IR revealed distinct ET‐IR profiles. Big‐ET‐1, which is barely detectable in control dogs, does represent the predominant ET in sick dogs. Regardless of the pathophysiological conditions, considerable amounts of high‐molecular weight ET‐1‐IR, most likely aggregated ET‐material, was found consistently. With respect to ET‐3, we constantly observed moderately increased concentrations, though no major difference of molecular pattern was evident between healthy and sick dogs. The data show a distinct regulation of ET‐1 and ET‐3 in dogs. Furthermore, specific molecular forms of ET‐IR were found to occur in various diseases. The endothelins may therefore prove to be of diagnostic importance in the pathophysiology of vascular diseases.
Splenic Infarction in 16 Dogs: A Retrospective Study
Authors: Hardie Elizabeth M. , Vaden Shelly L. , Spaulding Kathy , Malarkey David E.
Published: March 2010

Sixteen dogs with splenic infarction due to causes other than splenic torsion were identified. Dogs with splenic infarction often had multiple concurrent diseases, and surgical management of splenic infarction was associated with high mortality. Splenic infarction occurred in dogs with hypercoagulable conditions associated with liver disease, renal disease, and hyperadrenocorticism, or as a consequence of uniform splenomegaly, neoplasia, or thrombosis associated with cardiovascular disease. Clinical signs and common laboratory findings generally reflected the underlying disease process. A variety of splenic abnormalities were detected by abdominal ultrasound in 15 dogs, with the ventral extremity of the spleen being most often abnormal. Four dogs were euthanized or died because of the presence of severe systemic disease, whereas 12 dogs underwent laparotomy. Complete splenectomy was performed in 9 dogs and partial splenectomy was performed in 2 dogs. Seven dogs died in the immediate postoperative period, 3 required chronic veterinary care, and 2 had uncomplicated long‐term recoveries. Splenic infarction should be regarded as a sign of altered blood flow and coagulation, rather than as a primary disease, and surgical management should be reserved for patients with life‐threatening complications such as hemoabdomen or sepsis.
Lung Injury Leading to Respiratory Distress Syndrome in Young Dalmatian Dogs
Authors: Järvinen Anna‐Kaisa , Saario Elise , Andresen Erik , Happonen Irmeli , Saari Seppo , Rajamäki Minna
Published: March 2010

A progressive pulmonary disease resulting in severe respiratory failure and death in an average of 3 weeks was diagnosed in 11 young Dalmatian dogs. The dogs were from 4 litters, all genetically related by a common ancestor. The initial clinical signs were tachypnea and noisy respiration. Respiratory distress developed shortly before death and was characterized by strenuous and rapid respirations, along with cyanosis and vomiting. On blood gas analysis, there were severe arterial hypoxemia, hypercapma, and marked alveolar‐arterial oxygen difference. Radiographically, a diffuse pattern of alveolar, interstitial, and peribronchial densities was observed in the lungs. Most dogs developed pneumomediastinum and gastroesophageal intussusception in the terminal phase of the disease. There was no response to treatment with antibiotics, corticosteroids, diuretics, or oxygen. At necropsy, the lungs were wet, heavy, and relatively airless. Absence of 1 kidney in 2 dogs and severe internal hydrocephalus in 2 dogs were additional necropsy findings. Pulmonary histopathology included metaplasia and atypia of the alveolar and bronchiolar epithelium, a nonpurulent inflammatory reaction characterized mainly by mononuclear cells and macrophages, eosinophilic hyaline membrane formation, and focal pulmonary fibrosis. The histological manifestations were typical of acute lung injury. Clinically, the findings were consistent with adult respiratory distress syndrome (ARDS), except for the relatively long course. No known risk factors for ARDS, such as trauma, toxin exposure, infection, or endotoxemia could be identified. The relationship of the other abnormalities (ie, renal aplasia, hydrocephalus) to the pulmonary disease also remains obscure. An inherited defect is suspected, because segregation analysis of the 4 litters suggests autosomal recessive inheritance.
Artifactual Prolongation of the Activated Partial Thromboplastin Time Associated With Hemoconcentration in Dogs
Authors: O'Brien Susan R. , Sellers Teresa S. , Meyer Dennis J.
Published: March 2010

An inappropriate blood‐to‐anticoagulant ratio can cause an artifactual prolongation of the activated partial thromboplastin time (APTT) and prothrombin time (PT). In a drug safety study in dogs, we observed a 4‐to 5‐second increase in the APTT from baseline coincident with increased hematocrit values (56% to 65%) secondary to drug‐induced vomiting and diarrhea. The PT and platelet counts were unchanged, and there was no clinical evidence of bleeding associated with venipuncture. Although we were unable to sample the same dogs to investigate the possible effect of hemoconcentration on the prolonged APTT, the question was addressed by an in vitro study. The hematocrit value for citrated blood samples collected from healthy beagle dogs was increased by the addition of aliquots of red blood cell/plasma mixtures in vitro while maintaining a 9:1 blood‐to‐anticoagulant ratio. There was a 2‐to 4‐second prolongation of the APTT associated with hematocrit values of 55% to 61 %, but the PT was not prolonged. Adjustment of the blood‐to‐anticoagulant ratio corrected the prolongation. This study emphasizes the important relationship of the blood‐to‐anticoagulant ratio when measuring coagulation tests in hemoconcentrated samples.
Technetium 99m Sulfur Colloid Scintigraphy to Evaluate Reticuloendothelial System Function in Dogs With Portasystemic Shunts
Authors: Koblik Philip D. , Hornof William J.
Published: March 2010

In a retrospective study, technetium 99m sulfur colloid scintigraphy was used to evaluate reticuloendothelial system function in 61 dogs with single congenital and 40 dogs with multiple acquired portasystemic shunts. Whole body reticuloendothelial function was measured by calculating the plasma clearance rate constant from a dynamic study of liver uptake of99mTc sulfur colloid. Relative liver, spleen, and lung uptake, and a ratio of hepatic:extrahepatic uptake were measured on static equilibrium images. Results were compared with those of a group of 26 normal dogs. Compared with values for the group of normal dogs, the plasma clearance rate constant, relative liver uptake, and hepaticiextrahepatic uptake ratio were significantly decreased, and relative spleen and lung uptake were significantly increased in dogs with portasystemic shunts (P<.0001). The only significant difference between dogs with single congenital versus multiple acquired shunts was that the relative splenic uptake was higher in the former group (P<.0002). Based on these results, we concluded that dogs with portasystemic shunts have significantly impaired reticuloendothelial function. The primary cause of this dysfunction is likely a reduction in effective liver blood flow. Increases in spleen and lung reticuloendothelial activity did occur, but only partially compensated for the reduction of liver reticuloendothelial activity. Possible mechanisms for the increased spleen and lung uptake are discussed.