Professor Nicholas James Bacon FRCVS


Professor of Surgical Oncology
MA VetMB CertVR CertSAS DiplECVS DACVS FRCVS

Publications

Sarah E Boston, Lucinda L van Stee, Nicholas J Bacon, David Szentimrey, Barbara M Kirby, Sebastiaan van Nimwegen, Vincent A Wavreille (2019)Outcomes of eight cats with oral neoplasia treated with radical mandibulectomy, In: Veterinary surgery49(1)222pp. 222-232

To report outcomes after radical mandibulectomy in cats. Multi-institutional retrospective study. Eight cats were included. Medical records were searched for cats with confirmed oral neoplasia treated with radical mandibulectomy. Data collected included demographics, surgical procedure, histopathological diagnosis, postoperative management, and outcomes. Ages ranged from 8 to 17 years. All cats had 75% to 90% of the mandible removed and feeding tubes placed. Seven cats had squamous cell carcinoma, and one cat had a giant cell tumor. Six cats ate on their own postoperatively. Three cats had local recurrence and tumor-related died at 136 and 291 days. Six cats had no recurrence, with survival times of 156, 465, 608, and 1023 days, and two cats were still alive at 316 and 461 days after surgery. The three long-term survivors died of causes unrelated to oral neoplasia. One cat died at 156 days due to aspiration of food material. The overall estimated mean survival time was 712 days. After radical mandibulectomy, independent food intake was achieved in 6 of eight cats, and four cats lived longer than one year. Radical mandibulectomy should be considered for the treatment of extensive oral neoplasia in cats. Successful long-term outcomes are possible with aggressive supportive care perioperatively.

Laura M. Homer, Nicholas J. Bacon (2021)Hemipelvectomy to treat sarcoma of the proximal portion of the femur in a rabbit, In: Journal of the American Veterinary Medical Association258(2)pp. 192-196 Amer Veterinary Medical Assoc

CASE DESCRIPTION A 7-year-old sexually intact female rabbit was admitted to the hospital be- cause of a 6-month history of chronic right pelvic limb lameness. CLINICAL FINDINGS Clinical examination revealed a prominent right pelvic limb lameness and signs of pain on manipulation of the right hip joint, with a focal, well-defined soft tissue mass palpable in the right pelvic area. Pelvic radiography revealed a lytic hip joint lesion and CT detailed an expansile lesion within the proximal portion of the femur with an appearance consistent with a soft tissue mass. Histologic evaluation of incisional biopsy samples of the soft tissue mass revealed a poorly differentiated sarcoma. TREATMENT AND OUTCOME A hemipelvectomy was performed, and histologic evaluation of the soft tissue mass confirmed the diagnosis, with tumor-free margins achieved. The patient recovered well from surgery and had good mobility. The patient survived 21 months after surgery and died of a non-cancer-related disease. Anatomic dissection was described in a cadaver rabbit to aid future surgeries. CLINICAL RELEVANCE To the authors' knowledge, this was the first report of a hemipelvectomy performed in a rabbit. Hemipelvectomy is more routinely performed in canine and feline patients, but with the right candidate and owner commitment to aftercare, it may be safely and successfully performed in rabbits.

Nicholas J Bacon, James P Farese (2022)Urinary Tract, In: Simon T Kudnig, Bernard Séguin (eds.), Veterinary Surgical Oncologypp. 515-540 John Wiley & Sons, Inc

All animals scheduled for urinary tract biopsy should undergo a complete historical and physical evaluation. Laparoscopic‐assisted percutaneous needle core biopsies may obtain more representative tissue than US‐guided biopsies, and the biopsy site can be watched for evidence of hemorrhage. Fine needle aspirate (FNA) and needle core biopsy (e.g. Trucut) are infrequently used to diagnose renal tumors, possibly due to the concerns of abdominal tumor seeding associated with biopsy bleeding or biopsy‐tract implantation. Incisional or wedge biopsies will yield large tissue samples for histopathology and are typically taken from the junction of normal and what appears to be abnormal kidney. The majority of urinary neoplasia is epithelial in origin, and urothelial carcinomas display aggressive malignant behavior. For tumors that involve the urethra or trigone of the bladder and that cause an obstruction, placing a cystostomy tube can be a palliative solution to allow emptying of the bladder by the owners.

Objective: The aim of this study was to investigate the prevalence of pulmonary nodules at presentation in cases of soft tissue sarcoma (STS) in dogs with no previous thoracic imaging. Animals: Client-owned dogs with a histologic diagnosis of STS. Procedures: Dogs were retrospectively included in this study if the first thoracic imaging performed was at the time of presentation to our referral center. De novo and recurrent tumors were included, and information regarding tumor grade, history (primary mass vs scar vs recurrence), duration, location and size was also collected. Results: One hundred and forty-six dogs were included. Routine staging was performed with computed tomography (131 dogs, 89.7%) or 3-view thoracic radiographs (15 dogs, 10.3%). STS were grade 1 in 55.5% of dogs, grade 2 in 27.4% and grade 3 in 17.1%. Pulmonary nodules suggestive of metastasis were present in 11.7% of cases overall and in 6.5%, 5.6% and 37.5% of grade 1, grade 2 and grade 3 STS cases, respectively. Tumor grade (low/intermediate versus high) and tumor duration ( 3 months) were significantly associated with presence of pulmonary nodules at presentation. Conclusions and Clinical Relevance: This is the first large study reporting prevalence of pulmonary nodules at presentation in dogs with STS having had no previous thoracic imaging. The prevalence of pulmonary nodules suggestive of metastasis at presentation is low (

Simona Morabito, Swan Specchi, Pamela Di Donato, Danica Pollard, Ruth Dennis, Luisa De Risio, Nicholas J. Bacon, Maria Potamopoulou, Stefan Rupp, Daniele Corlazzoli, João Ribeiro, Francesca Cozzi, Konrad Jurina, Rodolfo Cappello, Edy Mercuriali, Katrin Beckmann, Thomas Flegel, Marika Menchetti, Florian König, Kaspar Matiasek, Marco Rosati (2023)Relationship between magnetic resonance imaging findings and histological grade in spinal peripheral nerve sheath tumors in dogs, In: Journal of veterinary internal medicine

Abstract Background Peripheral nerve sheath tumors (PNSTs) are a group of neoplasms originating from Schwann cells or pluripotent cell of the neural crest. Therapeutic options and prognosis are influenced by their degree of malignancy and location. Hypothesis/Objectives Identify magnetic resonance imaging (MRI) features predictive of PNST histologic grade. Animals Forty‐four dogs with histopathological diagnosis of spinal PNSTs and previous MRI investigation. Methods A multicenter retrospective study including cases with (a) histopathologic diagnosis of PNST and (b) MRI studies available for review. Histologic slides were reviewed and graded by a board‐certified pathologist according to a modified French system (FNCLCC) for grading soft tissue sarcomas. The MRI studies were reviewed by 2 board‐certified radiologists blinded to the grade of the tumor and the final decision on the imaging characteristics was reached by consensus. Relationships between tumor grade and histological and MRI findings were assessed using statistical analysis. Results Forty‐four cases met inclusion criteria; 16 patients were PNSTs Grade 1 (low‐grade), 19 were PNSTs Grade 2 (medium‐grade), and 9 were PNSTs Grade 3 (high‐grade). Large volume ( P = .03) and severe peripheral contrast enhancement ( P = .04) were significantly associated with high tumor grade. Degree of muscle atrophy, heterogeneous signal and tumor growth into the vertebral canal were not associated with grade. Conclusions and Clinical Importance Grade of malignancy was difficult to identify based on diagnostic imaging alone. However, some MRI features were predictive of high‐grade PNSTs including tumor size and peripheral contrast enhancement.

David John Brewer, Michael Macfarlane, Erin O'Connell, Nicholas J. Bacon (2022)Toxicity of zoledronic acid after intravenous administration: A retrospective study of 95 dogs, In: Journal of veterinary internal medicine36(1)pp. 253-258 Wiley

Background There is a paucity of veterinary literature on the safety or outcome of zoledronic acid (ZA) use in dogs for either bone pain or hypercalcemia. Hypothesis/Objectives The primary aim was to report the adverse events in dogs receiving intravenous administration of ZA. Animals Ninety-five dogs with ZA use. Methods A retrospective cohort study was performed; all dogs that received at least 1 dose of ZA and had a serum biochemistry profile performed before and after treatment were reviewed. Diagnosis, indication for treatment, adverse events and survival times were recorded. Results Ninety-five dogs met the inclusion criteria. Thirty-one (33%) received multiple intravenous infusions of ZA (range, 2-7), making a total of 166 administrations in all dogs. The dose range was 0.13 to 0.32 mg/kg, given at intervals of 4 to 6 weeks. Thirteen adverse events were recorded in 10 dogs: azotemia (n = 8), vomiting (n = 2), pancreatitis (n = 1), cutaneous ulceration (n = 1), and diarrhea (n = 1). Zoledronic acid could not be confirmed as the cause of azotemia in any case. The change in serum creatinine concentration from dose to dose was not related to the total dose received (P = .46). Five dogs (5%) changed Veterinary Comparative Oncology Group Common Terminology Criteria (VCOG-CTAE) renal/genitourinary grade after administration of ZA; their total dose 0.4 mg/kg (range, 0.26-0.66) was not significantly different to the group which did not change VCOG-CTAE renal/genitourinary grade 0.35 mg/kg (range, 0.2-1.50; P = .93). Conclusions and Clinical Importance Multiple doses of ZA were well tolerated in dogs within this study. A small number of dogs developed progressive azotemia which was not associated with cumulative dose.

Taranpreet Rai, Ambra Morisi, Barbara Bacci, Nicholas J. Bacon, Michael J. Dark, Tawfik Aboellail, Spencer A. Thomas, Miroslaw Bober, Roberto La Ragione, Kevin Wells (2022)Deep learning for necrosis detection using canine perivascular wall tumour whole slide images, In: Scientific Reports1210634

Necrosis seen in histopathology Whole Slide Images is a major criterion that contributes towards scoring tumour grade which then determines treatment options. However conventional manual assessment suffers from inter-operator reproducibility impacting grading precision. To address this, automatic necrosis detection using AI may be used to assess necrosis for final scoring that contributes towards the final clinical grade. Using deep learning AI, we describe a novel approach for automating necrosis detection in Whole Slide Images, tested on a canine Soft Tissue Sarcoma (cSTS) data set consisting of canine Perivascular Wall Tumours (cPWTs). A patch-based deep learning approach was developed where different variations of training a DenseNet-161 Convolutional Neural Network architecture were investigated as well as a stacking ensemble. An optimised DenseNet-161 with post-processing produced a hold-out test F1-score of 0.708 demonstrating state-of-the-art performance. This represents a novel first-time automated necrosis detection method in the cSTS domain as well specifically in detecting necrosis in cPWTs demonstrating a significant step forward in reproducible and reliable necrosis assessment for improving the precision of tumour grading.

Ambra Morisi, Taran Rai, Nicholas J. Bacon, Spencer A. Thomas, Miroslaw Bober, Kevin Wells, Michael J. Dark, Tawfik Aboellail, Barbara Bacci, Roberto M. La Ragione (2023)Detection of Necrosis in Digitised Whole-Slide Images for Better Grading of Canine Soft-Tissue Sarcomas Using Machine-Learning, In: Veterinary sciences10(1)45

The definitive diagnosis of canine soft-tissue sarcomas (STSs) is based on histological assessment of formalin-fixed tissues. Assessment of parameters, such as degree of differentiation, necrosis score and mitotic score, give rise to a final tumour grade, which is important in determining prognosis and subsequent treatment modalities. However, grading discrepancies are reported to occur in human and canine STSs, which can result in complications regarding treatment plans. The introduction of digital pathology has the potential to help improve STS grading via automated determination of the presence and extent of necrosis. The detected necrotic regions can be factored in the grading scheme or excluded before analysing the remaining tissue. Here we describe a method to detect tumour necrosis in histopathological whole-slide images (WSIs) of STSs using machine learning. Annotated areas of necrosis were extracted from WSIs and the patches containing necrotic tissue fed into a pre-trained DenseNet161 convolutional neural network (CNN) for training, testing and validation. The proposed CNN architecture reported favourable results, with an overall validation accuracy of 92.7% for necrosis detection which represents the number of correctly classified data instances over the total number of data instances. The proposed method, when vigorously validated represents a promising tool to assist pathologists in evaluating necrosis in canine STS tumours, by increasing efficiency, accuracy and reducing inter-rater variation.

Erika J. Villedieu, Audrey Petite, Janet Godolphin, Nick Bacon (2020)Prevalence of pulmonary nodules suggestive of metastasis at presentation in dogs with cutaneous or subcutaneous soft tissue sarcoma, In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION AMER VETERINARY MEDICAL ASSOC

Objective: The aim of this study was to investigate the prevalence of pulmonary nodules at presentation in cases of soft tissue sarcoma (STS) in dogs with no previous thoracic imaging. Animals: Client-owned dogs with a histologic diagnosis of STS. Procedures: Dogs were retrospectively included in this study if the first thoracic imaging performed was at the time of presentation to our referral center. De novo and recurrent tumors were included, and information regarding tumor grade, history (primary mass vs scar vs recurrence), duration, location and size was also collected. Results: One hundred and forty-six dogs were included. Routine staging was performed with computed tomography (131 dogs, 89.7%) or 3-view thoracic radiographs (15 dogs, 10.3%). STS were grade 1 in 55.5% of dogs, grade 2 in 27.4% and grade 3 in 17.1%. Pulmonary nodules suggestive of metastasis were present in 11.7% of cases overall and in 6.5%, 5.6% and 37.5% of grade 1, grade 2 and grade 3 STS cases, respectively. Tumor grade (low/intermediate versus high) and tumor duration ( 3 months) were significantly associated with presence of pulmonary nodules at presentation. Conclusions and Clinical Relevance: This is the first large study reporting prevalence of pulmonary nodules at presentation in dogs with STS having had no previous thoracic imaging. The prevalence of pulmonary nodules suggestive of metastasis at presentation is low (

Jasmine Moser, Nick Bacon, Sergio Guilherme (2023)Intrahepatic splenosis as a differential diagnosis for hepatic neoplasia in a dog, In: Veterinary record case reports

Abstract Intrahepatic splenosis is the heterotopic autotransplantation of splenic tissue secondary to splenic trauma or splenectomy. A 12‐year‐old Cairn terrier was referred due to lethargy, collapse and abdominal discomfort. Abdominal ultrasound and a computed tomography scan (CT) revealed an intrahepatic mass in the left medial liver lobe. The dog underwent surgery for liver lobectomy, and subsequent histopathology revealed intrahepatic splenosis. The dog had undergone splenectomy 3 years previously due to splenic rupture following an abdominal trauma.

Nicholas J Bacon (2023)Primary Hyperparathyroidism, In: Eric Monnet (eds.), Small Animal Soft Tissue Surgerypp. 747-766 John Wiley & Sons, Inc

Primary hyperparathyroidism is rare, comprising 0.5% cases referred to one large academic institution. All clinical signs associated with primary hyperparathyroidism are related to the hypercalcemia secondary to the elevation in parathyroid hormone. Primary hyperparathyroidism is rare in cats, with few cases described to date. Since most hyperfunctioning parathyroid tissue occurs in the normal location of the parathyroid glands, cervical ultrasound is economical and readily available, and so is commonly the first line of imaging modality. Chronic renal failure is commonly associated with hyperparathyroidism through parathyroid gland hyperplasia. Exploratory surgery with parathyroidectomy in dogs with primary hyperparathyroidism serves as both a diagnostic test and definitive therapy. Preoperative treatment of hypercalcemia is contentious and there are no published standards. The greatest postoperative concern, reportedly occurring in 8–63% dogs, is hypocalcemia due to chronic suppression of the remaining parathyroid glands through negative feedback from the hypersecretory tumor.

Andrea Galliano, Ivan A Kalmukov, JANET DIANA GODOLPHIN, Rui Ferreira, Daisy J Norgate, NICHOLAS JAMES BACON (2022)Intraoperative cell salvaging: ex vivo evaluation of two swab washing methods, In: American journal of veterinary research83(10) AVMA

OBJECTIVE To compare erythrocyte recovery by a cell salvage device between swab-washing by manual agitation or filtration. SAMPLE 12 recently expired units of canine packed RBCs. PROCEDURE The packed RBC units underwent quality analysis before donation from a pet blood bank. Each unit was volume-expanded with anticoagulant and subsequently divided into 2 equal aliquots used to soak surgical swabs before washing. Two different swab-washing techniques were evaluated—standard swab-washing–manual agitation (SW-MA) and swab-washing–filtration (SW-F)—with a novel prototype device. The resulting bloody fluid was processed using the Cell Saver Elite Autotransfusion System (Haemonetics). The volume, manual PCV, CBC, and RBC mass, calculated as the product of the volume and PCV, were measured before and after salvaging. Last, the RBC mass recovery was recorded as a percentage. RESULTS The RBC mass recovered from SW-MA and SW-F averaged 85.73% and 83.99%, respectively. There was no significant difference in RBC recovery between the 2 methods (P = .52). CLINICAL RELEVANCE SW-MA and SW-F recovered a similar quantity of RBCs from blood-soaked swabs in an ex vivo setting.

NJ Bacon (2013)Primary Hyperparathyroidism, In: Small Animal Soft Tissue Surgerypp. 1-16

© 2013 John Wiley & Sons, Ltd.The parathyroid glands in dogs and cats are tan-colored ovoid structures closely associated with each thyroid gland. Parathyroid hormone (PTH) release is controlled by calcium receptors on the chief cells in the parathyroid glands in response to hypocalcemia. PTH has a short half-life (3-5 min) in serum and so a steady rate of secretion is necessary to maintain serum PTH concentrations. Natural variations in PTH concentration occur in healthy dogs. Exploratory surgery with parathyroidectomy in dogs with primary hyperparathyroidism serves as both a diagnostic test and definitive therapy. Surgery should be advocated to reduce the risk of urolithiasis and urinary tract infection, as well as improving the clinical signs seen with hypercalcemia such as polydipsia, polyuria, weakness, and decreased appetite. Surgical excision alone is the most widely performed treatment for primary hyperparathyroidism and a cure rate of 94% is reported if all autonomously functioning parathyroid tissue is removed.

NJ Bacon, JP Farese (2013)Urinary Tractpp. 365-382
NJ Bacon, DA Kamstock (2013)Spleenpp. 387-392
SE Kim, RF Giglio, DJ Reese, SL Reese, NJ Bacon, GW Ellison (2013)Comparison of computed tomographic angiography and ultrasonography for the detection and characterization of portosystemic shunts in dogs., In: Vet Radiol Ultrasound54(6)pp. 569-574

The purpose of this retrospective study was to compare the accuracy of computed tomographic angiography (CTA) and abdominal ultrasonography in detecting and characterizing portosystemic shunts (PSS) in dogs. Medical records of 76 dogs that underwent CTA and/or abdominal ultrasonography suspected to have PSS were reviewed. Presence or absence, and characterization of PSS (when present) on CTA were reviewed by a board-certified veterinary radiologist that was blinded to the clinical findings. The abdominal ultrasonography findings were reviewed from the medical records. Visualization and description of the origin and insertion of PSS on CTA and abdominal ultrasonography were related with laboratory, surgical, or mesenteric portographic confirmation of the presence or absence of PSS. The sensitivity for detection of PSS with CTA (96%) was significantly higher than abdominal ultrasonography (68%; P < 0.001). The specificities for CTA and abdominal ultrasonography were 89% and 84%, respectively (P = 0.727). Computed tomographic angiography detected the correct origin in 15 of 16 dogs and correct insertion in 15 of 16 dogs with congenital PSS. Abdominal ultrasonography detected the correct origin in 24 of 30 dogs and correct insertion in 20 of 33 dogs with congenital PSS. Multiple acquired PSS were seen in four of five dogs and in one of six dogs on CTA and abdominal ultrasonography, respectively. Computed tomographic angiography was 5.5 times more likely to correctly ascertain the presence or absence of PSS when compared to abdominal ultrasonography (P = 0.02). Findings indicated that CTA is a noninvasive diagnostic modality that is superior to abdominal ultrasonography for the detection and characterization of PSS in dogs.

JL Covey, JP Farese, NJ Bacon, SP Schallberger, P Amsellem, RP Cavanaugh, RJ Milner (2014)Stereotactic Radiosurgery and Fracture Fixation in 6 Dogs With Appendicular Osteosarcoma, In: VETERINARY SURGERY43(2)pp. 174-181 WILEY-BLACKWELL
Z Belshaw, NJ Bacon, RD Foale, PM Mannion, R Reuter (2005)Pancreatic mixed acinar-endocrine carcinoma in a dog., In: Vet Comp Oncol3(3)pp. 145-148

A 10.5-year-old crossbreed dog was presented with a history of hypoglycaemic episodes and elevated serum insulin concentration. A pancreatic mass was removed at surgery along with an enlarged draining lymph node. An unresectable hepatic nodule was also present. Immunohistochemistry confirmed the pancreatic and lymph node masses as functional mixed acinar-endocrine carcinoma, previously unreported in domestic species. Persistent hypoglycaemia and hyperinsulinaemia post-operatively was highly suggestive of the hepatic mass being a functional metastasis. The dog was managed on prednisolone and remained asymptomatic 9 months post-operatively. This tumour type has only been rarely reported in human patients and may highlight the need for more rigorous immunohistochemical staining of pancreatic masses in veterinary species to identify the prevalence of this tumour type.

KL Kelsey, LN Kubicek, NJ Bacon, T Torres, SA Robertson (2017)Neuromuscular blockade and inspiratory breath hold during stereotactic body radiation therapy for treatment of heart base tumors in four dogs, In: Journal of the American Veterinary Medical Association250(2)pp. 199-204

CASE DESCRIPTION 4 dogs were examined because of pleural effusion and ventricular tachycardia, coughing and supraventricular tachycardia, appendicular osteosarcoma, and syncopal episodes. CLINICAL FINDINGS In all 4 dogs, a heart base tumor was identified by means of thoracic CT. TREATMENT AND OUTCOME In all 4 dogs, the heart base tumors were treated by means of stereotactic body radiation therapy. Dogs were anesthetized, and neuromuscular blockade was achieved with atracurium or vecuronium. A circle rebreathing system with 15 m (50 feet) of anesthetic tubing coursing through the vault wall was used to connect the patient to the anesthesia machine, which was located in the control room. After a brief period of hyperventilation, an inspiratory breath was held at 20 cm H2O for the duration of beam delivery. Each beam delivery lasted between 30 and 100 seconds. Immediately following the breath hold, assisted ventilation was resumed. Mean treatment delivery time for each patient was 26 minutes; mean total anesthesia time was 89 minutes. All patients recovered without complications. There was no evidence of hemoglobin desaturation or hypercapnia during the anesthetic procedure.

Ying Wu, Yu-Mei Chang, Gerry Polton, Anneliese J. Stell, Balazs Szladovits, Michael Macfarlane, Laureen M. Peters, Simon L. Priestnall, Nicholas J. Bacon, Kelvin Kow, Sarah Stewart, Eshita Sharma, Michelle R. Goulart, John Gribben, Dong Xia, Oliver A. Garden (2020)Gene Expression Profiling of B Cell Lymphoma in Dogs Reveals Dichotomous Metabolic Signatures Distinguished by Oxidative Phosphorylation, In: Frontiers in oncology10307pp. 307-307 Frontiers Media Sa

Gene expression profiling has revealed molecular heterogeneity of diffuse large B cell lymphoma (DLBCL) in both humans and dogs. Two DLBCL subtypes based on cell of origin are generally recognized, germinal center B (GCB)-like and activated B cell (ABC)-like. A pilot study to characterize the transcriptomic phenotype of 11 dogs with multicentric BCL yielded two molecular subtypes distinguished on the basis of genes important in oxidative phosphorylation. We propose a metabolic classification of canine BCL that transcends cell of origin and shows parallels to a similar molecular phenotype in human DLBCL. We thus confirm the validity of this classification scheme across widely divergent mammalian taxa and add to the growing body of literature suggesting cellular and molecular similarities between human and canine non-Hodgkin lymphoma. Our data support a One Health approach to the study of DLBCL, including the advancement of novel therapies of relevance to both canine and human health.

Clarisse D'Aout, Helen Renfrew, Melanie Dobromylskyj, Nicholas Bacon, Annika Herrmann, Samantha S. Taylor (2020)Intranasal proliferative fibro-osseous dysplasia in a domestic longhair cat, In: JOURNAL OF FELINE MEDICINE AND SURGERY OPEN REPORTS6(1) Sage

Case summary A 13-year-old female domestic longhair cat was presented for further investigation of chronic sneezing combined with a right-sided nasal discharge. A CT scan of the head revealed a locally invasive, aggressive right nasal mass radiographically consistent with a malignant neoplastic process. Histopathology on rhinoscopically guided biopsies revealed an unusual pathology consistent with fibro-osseous hyperplasia/ dysplasia. Surgical treatment via a ventral rhinotomy and curettage was performed, and the diagnosis confirmed by repeat histopathology. The cat's clinical signs significantly improved postoperatively. Relevance and novel information This case report describes an unusual feline nasal pathology. To our knowledge, there are no previous reports of a non-neoplastic, non-inflammatory expansile feline nasal tumour. Also described are the CT and histological appearance of the mass, and the difficulties encountered obtaining the definitive diagnosis. Information regarding the prognosis following surgical removal of proliferative fibro-osseous lesions in cats is poor, especially from the nasal cavity where clean margins may well be impossible to obtain. In this case, surgical resection improved clinical signs and the cat remains well at 15 months post-procedure.

MJ Day, SM Henderson, Z Belshaw, NJ Bacon (2004)An immunohistochemical investigation of 18 cases of feline nasal lymphoma, In: JOURNAL OF COMPARATIVE PATHOLOGY130(2-3)pp. 152-161 ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD
MM Dennis, KD McSporran, NJ Bacon, FY Schulman, RA Foster, BE Powers (2011)Prognostic Factors for Cutaneous and Subcutaneous Soft Tissue Sarcomas in Dogs, In: VETERINARY PATHOLOGY48(1)pp. 73-84 SAGE PUBLICATIONS INC
JD Webster, MM Dennis, N Dervisis, J Heller, NJ Bacon, PJ Bergman, D Bienzle, G Cassali, M Castagnaro, J Cullen, DG Esplin, L Pena, MH Goldschmidt, KA Hahn, CJ Henry, E Hellmen, D Kamstock, J Kirpensteijn, BE Kitchell, RL Amorim, SD Lenz, TP Lipscomb, M McEntee, LD McGill, CA McKnight, PM McManus, AS Moore, PF Moore, SD Moroff, H Nakayama, NC Northrup, G Sarli, T Scase, K Sorenmo, FY Schulman, AM Shoieb, RC Smedley, WL Spangler, E Teske, DH Thamm, VE Valli, W Vernau, H von Euler, SJ Withrow, SE Weisbrode, J Yager, M Kiupel (2011)Recommended Guidelines for the Conduct and Evaluation of Prognostic Studies in Veterinary Oncology, In: VETERINARY PATHOLOGY48(1)pp. 7-18 SAGE PUBLICATIONS INC
NJ Bacon, RAS White (2003)Extrahepatic biliary tract surgery in the cat: a case series and review, In: JOURNAL OF SMALL ANIMAL PRACTICE44(5)pp. 231-235 BRITISH VETERINARY ASSOC
JP Bray, DR Worley, RA Henderson, SE Boston, KG Mathews, G Romanelli, NJ Bacon, JM Liptak, TJ Scase (2014)Hemipelvectomy: Outcome in 84 Dogs and 16 Cats. A Veterinary Society of Surgical Oncology Retrospective Study, In: VETERINARY SURGERY43(1)pp. 27-37 WILEY-BLACKWELL
NJ Bacon, RL Gilbert, DE Bostock, RAS White (2003)Total ear canal ablation in the cat: indications, morbidity and long-term survival, In: JOURNAL OF SMALL ANIMAL PRACTICE44(10)pp. 430-434 BRITISH VETERINARY ASSOC
DA Kamstock, EJ Ehrhart, DM Getzy, NJ Bacon, KM Rassnick, SD Moroff, SM Liu, RC Straw, CA McKnight, RL Amorim, D Bienzle, GD Cassali, JM Cullen, MM Dennis, DG Esplin, RA Foster, MH Goldschmidt, AD Gruber, E Hellmen, EW Howerth, P Labelle, SD Lenz, TP Lipscomb, E Locke, LD McGill, MA Miller, PJ Mouser, D O'Toole, RR Pool, BE Powers, JA Ramos-Vara, P Roccabianca, AD Ross, A Sailasuta, G Sarli, TJ Scase, FY Schulman, AM Shoieb, K Singh, D Sledge, RC Smedley, KC Smith, WL Spangler, B Steficek, PC Stromberg, VE Valli, J Yager, M Kiupel (2011)Recommended Guidelines for Submission, Trimming, Margin Evaluation, and Reporting of Tumor Biopsy Specimens in Veterinary Surgical Pathology, In: VETERINARY PATHOLOGY48(1)pp. 19-31 SAGE PUBLICATIONS INC
TP Batlivala, NJ Bacon, AC Avery, K Barabas, RG Gunn-Christie, J Conway, PR Avery (2010)Paraneoplastic T cell lymphocytosis associated with a thymoma in a dog, In: JOURNAL OF SMALL ANIMAL PRACTICE51(9)pp. 491-494 WILEY-BLACKWELL
JP Farese, J Kirpensteijn, M Kik, NJ Bacon, SS Waltman, B Seguin, M Kent, J Liptak, R Straw, MN Chang, Y Jiang, SJ Withrow (2009)Biologic Behavior and Clinical Outcome of 25 Dogs with Canine Appendicular Chondrosarcoma Treated by Amputation: A Veterinary Society of Surgical Oncology Retrospective Study, In: VETERINARY SURGERY38(8)pp. 914-919 WILEY-BLACKWELL PUBLISHING, INC
M Risselada, GW Ellison, NJ Bacon, MMR Polyak, J van Gilder, K Kirkby, SE Kim (2010)Comparison of 5 Surgical Techniques for Partial Liver Lobectomy in the Dog for Intraoperative Blood Loss and Surgical Time, In: VETERINARY SURGERY39(7)pp. 856-862 WILEY-BLACKWELL
SL Parfitt, RJ Milner, ME Salute, DE Hintenlang, JP Farese, NJ Bacon, FJ Bova, DA Rajon, DM Lurie (2011)Radiosensitivity and capacity for radiation-induced sublethal damage repair of canine transitional cell carcinoma (TCC) cell lines, In: VETERINARY AND COMPARATIVE ONCOLOGY9(3)pp. 232-240 WILEY-BLACKWELL
RP Cavanaugh, JP Farese, NJ Bacon, DM Lurie, RJ Milner (2011)Oronasal Fistula Repair Utilizing a Temporalis Muscle Flap in a Dog with Severe Trismus, In: JOURNAL OF THE AMERICAN ANIMAL HOSPITAL ASSOCIATION47(6)pp. 447-454 AMER ANIMAL HOSPITAL ASSOC
KA Wirth, K Kow, ME Salute, NJ Bacon, RJ Milner (2014)In vitro effects of Yunnan Baiyao on canine hemangiosarcoma cell lines., In: Vet Comp Oncol

Yunnan Baiyao is a Chinese herbal medicine that has been utilized for its anti-inflammatory, haemostatic, wound healing and pain relieving properties in people. It has been utilized in the veterinary profession to control bleeding in dogs with hemangiosarcoma (HSA) and has been anecdotally reported to prolong survival times in dogs with this neoplasm. This study evaluated the in vitro activity of Yunnan Baiyao against three canine HSA cell lines after treatment with increasing concentrations of Yunnan Baiyao (50, 100, 200, 400, 600 and 800 µg mL(-1) ) at 24, 48 and 72 h. Mean half maximum inhibitory concentration (IC50 ) at 72 h for DEN, Fitz, SB was 369.9, 275.9 and 325.3 µg mL(-1) , respectively. Caspase-3/7 activity increased in correlation with the IC50 in each cell line which was confirmed by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL, APO-BRDU Kit; BD Biosciences, San Jose, CA, USA) assay. VEGF in cell supernatant was also quantified. Overall, the study found that Yunnan Baiyao causes dose and time dependent HSA cell death through initiation of caspase-mediated apoptosis, which supports future studies involving Yunnan Baiyao.

RE McCally, SE Kim, NJ Bacon, MD Winter, AA Cords, JA Conway (2012)Surgical Management of a Subepiglottic Thyroglossal Duct Cyst in a Dog, In: JOURNAL OF THE AMERICAN ANIMAL HOSPITAL ASSOCIATION48(3)pp. 198-202 AMER ANIMAL HOSPITAL ASSOC
JA Rubin, SE Kim, NJ Bacon (2013)Traumatic tympanic bulla fracture, In: JOURNAL OF SMALL ANIMAL PRACTICE54(11)pp. 605-609 WILEY-BLACKWELL
JL Covey, JP Farese, NJ Bacon, SP Schallberger, P Amsellem, RP Cavanaugh, RJ Milner (2014)Stereotactic radiosurgery and fracture fixation in 6 dogs with appendicular osteosarcoma., In: Vet Surg43(2)pp. 174-181

OBJECTIVE: To evaluate clinical outcome of dogs with appendicular osteosarcoma (OSA) treated with stereotactic radiosurgery (SRS) and subsequent internal fixation of a pathologic fracture. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs with spontaneous-occurring appendicular OSA (n = 6). METHODS: Medical records (May 2002-January 2008) of dogs that had SRS for appendicular OSA were reviewed. Dogs were included if they had a pathologic fracture either before or after SRS and were treated with internal fixation. Signalment, history, physical examination findings, clinicopathologic data, diagnostic imaging findings, biopsy results, surgical complications, number of surgeries, adjuvant therapy, development of metastatic disease and cause of death were recorded. RESULTS: Six dogs met the inclusion criteria. Two dogs had a pathologic fracture at admission and 4 dogs developed a fracture after SRS with a mean ± SD time to fracture development of 6.25 ± 1.65 months. The first 3 fractures were repaired using an open approach and the latter three using minimally invasive percutaneous osteosynthesis (MIPO). Infection occurred in 5 dogs and implant failure in 3. Limb function was subjectively assessed as good in all dogs when the implants were stable and infections were subclinical. Survival times ranged from 364-897 days; 1 dog was lost to follow-up. CONCLUSIONS: Fracture repair using internal fixation should be considered a viable limb-sparing alternative for pathologic fractures that have been treated with SRS.

SE Boston, NJ Bacon, WTN Culp, J Bhandal, C Bruce, RP Cavanaugh, MH Hamilton, JD Lincoln, JM Liptak, S Scharvogel (2011)Outcome after Repair of a Sarcoma-Related Pathologic Fracture in Dogs: A Veterinary Society of Surgical Oncology Retrospective Study, In: VETERINARY SURGERY40(4)pp. 431-437 WILEY-BLACKWELL
CE Fahey, RJ Milner, K Kow, NJ Bacon, ME Salute (2013)Apoptotic effects of the tyrosine kinase inhibitor, masitinib mesylate, on canine osteosarcoma cells, In: ANTI-CANCER DRUGS24(5)pp. 519-526 LIPPINCOTT WILLIAMS & WILKINS
RNA Gear, NJ Bacon, S Langley-Hobbs, PJ Watson, N Woodger, ME Herrtage (2006)Panniculitis, polyarthritis and osteomyelitis associated with pancreatic neoplasia in two dogs, In: JOURNAL OF SMALL ANIMAL PRACTICE47(7)pp. 400-404 BLACKWELL PUBLISHING
L Novella, B Carobbi, NJ Bacon, RAS White (2008)Hypobaric intrathecal anaesthesia for partial hemipelvectomy in a dog, In: VETERINARY AND COMPARATIVE ORTHOPAEDICS AND TRAUMATOLOGY21(1)pp. 89-93 SCHATTAUER GMBH-VERLAG MEDIZIN NATURWISSENSCHAFTEN
SD Guérios, DM Silva, CH Souza, NJ Bacon (2015)Surgical placement and management of jugular vascular access ports in dogs and cats: Description of technique<sup>¤</sup>, In: Revista Colombiana de Ciencias Pecuarias28(3)pp. 165-171

© 2015, Universidad de Antioquia. All rights reserved.Background: vascular access ports (VAPs) are designed to allow repeated access to the vascular system with minimum patient distress. Objective: to describe the surgical technique, care and complications of jugular VAPs currently used at the Veterinary Oncology Service of the University of Florida Small Animal Hospital. Conclusion: the VAPs can remain in site for long terms (months) with minimum complications, and its placement is a reliable technique that should be considered by veterinarians, particularly for a long-term treatment.

SE Boston, F Duerr, N Bacon, S Larue, EJ Ehrhart, S Withrow (2007)Intraoperative radiation for limb sparing of the distal aspect of the radius without transcarpal plating in five dogs., In: Vet Surg36(4)pp. 314-323

OBJECTIVES: To evaluate intraoperative irradiation (IORT) as a method of limb spare with preservation of the radiocarpal joint. STUDY DESIGN: Prospective case series. ANIMALS: Dogs (n=5) with stage II sarcoma of the distal aspect of the radius. METHODS: A bone segment containing the tumor was isolated surgically, treated by IORT, reimplanted, and secured by internal fixation. In 1 dog, the postradiation tumor bed was curetted and filled with bone cement. Dogs were administered alternating adriamycin and carboplatin starting 2 weeks after IORT and monitored at regular intervals. RESULTS: Four dogs had osteosarcoma and 1 had undifferentiated sarcoma. Implant failure (n=3), deep tissue infection (3), and pathologic fracture (3) resulted in amputation (3) or pancarpal plating (2). The dog with undifferentiated sarcoma was euthanatized because of suspected tumor recurrence 4 months postoperatively. Osteotomy healing was documented by radiography (1), histopathology (2), or by direct observation (2). CONCLUSIONS: A technique for limb-sparing surgery of the distal portion of the radius in dogs using IORT had advantages include healing of the autograft and a source for a perfectly fitting autograft but did not appear to offer any advantage with respect to infection rate. Long-term preservation of the radiocarpal joint was not successful. CLINICAL RELEVANCE: It was not possible to preserve the function of the radiocarpal joint and so this technique cannot be recommended currently. Further study is needed to evaluate whether or not IORT can be considered in combination with pancarpal plating and possibly curettage and cementation of the tumor to prevent subchondral bone collapse.

NJ Bacon, NR Ehrhart, WS Dernell, M Lafferty, SJ Withrow (2008)Use of alternating administration of carboplatin and doxorubicin in dogs with microscopic metastases after amputation for appendicular osteosarcoma: 50 cases (1999-2006), In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION232(10)pp. 1504-1510 AMER VETERINARY MEDICAL ASSOC
AF Schmidt, RHH Groenwold, P Amsellem, N Bacon, OH Klungel, AW Hoes, A de Boer, K Kow, K Maritato, J Kirpensteijn, M Nielen (2016)Which dogs with appendicular osteosarcoma benefit most from chemotherapy after surgery? Results from an individual patient data meta-analysis, In: PREVENTIVE VETERINARY MEDICINE125pp. 116-125 ELSEVIER SCIENCE BV
L Kubicek, R Milner, Q An, K Kow, M Chang, K Cooke, L Fox, J Farese, N Bacon, D Lurie (2016)OUTCOMES AND PROGNOSTIC FACTORS ASSOCIATED WITH CANINE SINONASAL TUMORS TREATED WITH CURATIVE INTENT CONE-BASED STEREOTACTIC RADIOSURGERY (1999-2013), In: VETERINARY RADIOLOGY & ULTRASOUND57(3)pp. 331-340 WILEY-BLACKWELL
NJ Bacon, WS Dernell, N Ehrhart, BE Powers, SJ Withrow (2007)Evaluation of primary re-excision after recent inadequate resection of soft tissue sarcomas in dogs: 41 cases (1999-2004), In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION230(4)pp. 548-554 AMER VETERINARY MEDICAL ASSOC
AR Coomer, N Bacon (2009)Primary anastomosis of segmental external auditory canal atresia in a cat, In: JOURNAL OF FELINE MEDICINE AND SURGERY11(10)pp. 864-868 SAGE PUBLICATIONS LTD
A Coomer, J Farese, R Milner, J Liptak, N Bacon, D Lurie (2009)Radiation therapy for canine appendicular osteosarcoma, In: VETERINARY AND COMPARATIVE ONCOLOGY7(1)pp. 15-27 WILEY-BLACKWELL PUBLISHING, INC
TR Sissener, NJ Bacon, E Friend, DM Anderson, RAS White (2006)Combined clotrimazole irrigation and depot therapy for canine nasal aspergillosis, In: JOURNAL OF SMALL ANIMAL PRACTICE47(6)pp. 312-315 BLACKWELL PUBLISHING
JP Farese, NJ Bacon, NP Ehrhart, J Bush, EJ Ehrhart, SJ Withrow (2008)Oesophageal leiomyosarcoma in dogs: surgical management and clinical outcome of four cases, In: VETERINARY AND COMPARATIVE ONCOLOGY6(1)pp. 31-38 BLACKWELL PUBLISHING
Ivan A Kalmukov, Andrea Galliano, Janet Godolphin, Rui Ferreira, Ines Cardoso, Daisy J Norgate, Nicholas J Bacon (2022)Ex vivo evaluation of a novel cell salvage device to recover canine erythrocytes, In: Veterinary surgery Wiley

Objective To determine the ability of a cell salvage device to recover canine erythrocytes by direct aspiration of diluted packed red blood cells (pRBC) and saline rinse from blood-soaked surgical swabs. Study design Experimental study. Sample population Twelve recently expired units of canine pRBC. Methods pRBC units donated from a pet blood bank (after quality analysis) were diluted with anticoagulant, divided into two equal aliquots, and subsequently harvested by direct suction (Su), or soaked into swabs, saline-rinsed and suctioned (Sw). The volume of product, manual packed cell volume (PCV), and red blood cell mass (rbcM) were measured and compared before and after salvaging. The rbcM recovery was recorded as percentage ([rbcM post salvage]/[rbcM presalvage]x100). Statistical analysis of all measured values was performed (significance p 

N Bacon, CHDM Souza, S Franz (2016)Total cysto-prostatectomy: Technique description and results in 2 dogs, In: CANADIAN VETERINARY JOURNAL-REVUE VETERINAIRE CANADIENNE57(2)pp. 141-146 CANADIAN VET MED ASSOC
LC Cuddy, NJ Bacon, AR Coomer, CJ Jeyapaul, BJ Sheppard, MD Winter (2010)Excision of a congenital laryngeal cyst in a five-month-old dog via a lateral extraluminal approach, In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION236(12)pp. 1328-1333 AMER VETERINARY MEDICAL ASSOC
K Kirkby, J Wheeler, J Farese, G Ellison, N Bacon, C Sereda, D Lewis (2009)Surgical views: Vacuum-assisted wound closure: application and mechanism of action., In: Compend Contin Educ Vet31(12)pp. E1-E7

Vacuum-assisted closure (VAC) is a wound management therapy that creates local negative pressure over a wound bed to promote healing. Benefits of VAC therapy include removal of fluid from the extravascular space, improved circulation, enhanced granulation tissue formation, increased bacterial clearance, and hastening of wound closure. This article describes the mechanism of action of VAC therapy, reviews application techniques, and lists potential complications and contraindications.

HA Phelps, CA Kuntz, RJ Milner, BE Powers, NJ Bacon (2011)Radical excision with five-centimeter margins for treatment of feline injection-site sarcomas: 91 cases (1998-2002), In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION239(1)pp. 97-106 AMER VETERINARY MEDICAL ASSOC
KM Thieman, KA Kirkby, A Flynn-Lurie, AM Grooters, NJ Bacon (2011)Diagnosis and treatment of truncal cutaneous pythiosis in a dog, In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION239(9)pp. 1232-1235 AMER VETERINARY MEDICAL ASSOC
KA Kirkby, JL Wheeler, JP Farese, GW Ellison, NJ Bacon, CW Sereda, DD Lewis (2010)Vacuum-assisted wound closure: Clinical applications, In: Compendium: Continuing Education For Veterinarians32(3)

Vacuum-assisted closure (VAC) is a wound management system that exposes a wound bed to local negative pressure to promote healing. Benefits of VAC therapy include removal of fluid from the extravascular space, improved circulation, enhanced granulation tissue formation, and increased bacterial clearance. VAC therapy has been used extensively in human patients to treat a variety of acute and chronic wound conditions. This article reviews the use of VAC therapy in a variety of wound conditions and describes our experiences with using VAC therapy in dogs and cats at the University of Florida. © Copyright 2010 MediMedia Animal Health.

ND Jeffery, CE Talbot, PM Smith, NJ Bacon (2006)Acquired idiopathic laryngeal paralysis as a prominent feature of generalised neuromuscular disease in 39 dogs, In: VETERINARY RECORD158(1)pp. 17-21 BRITISH VETERINARY ASSOC
SD Guerios, DM Silva, CHM Souza, NJ Bacon (2015)Surgical placement and management of jugular vascular access ports in dogs and cats: description of technique, In: REVISTA COLOMBIANA DE CIENCIAS PECUARIAS28(3)pp. 265-271 UNIV ANTIOQUIA, FAC CIENCIAS AGRARIAS
KC Kligman, SE Kim, MD Winter, NJ Bacon, HL Krellner, JK Levy (2009)What Is Your Diagnosis?, In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION235(8)pp. 945-946 AMER VETERINARY MEDICAL ASSOC
PM Amsellem, LE Selmic, JM Wypij, NJ Bacon, WTN Culp, NP Ehrhart, BE Powers, H Stryhn, JP Farese (2014)Appendicular osteosarcoma in small-breed dogs: 51 cases (1986-2011), In: JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION245(2)pp. 203-210 AMER VETERINARY MEDICAL ASSOC
KA Kirkby, JL Wheeler, JP Farese, GW Ellison, NJ Bacon, CW Sereda, DD Lewis (2009)Vacuum-Assisted Wound Closure: Application and Mechanism of Action, In: COMPENDIUM-CONTINUING EDUCATION FOR VETERINARIANS31(12)pp. 568-+ VETERINARY LEARNING SYSTEMS
M Risselada, MMR Polyak, GW Ellison, NJ Bacon, JM Van Gilder, AR Coomer, KE Thieman (2010)Postmortem evaluation of surgery site leakage by use of in situ isolated pulsatile perfusion after partial liver lobectomy in dogs, In: AMERICAN JOURNAL OF VETERINARY RESEARCH71(3)pp. 262-267 AMER VETERINARY MEDICAL ASSOC
NJ Bacon, DM Anderson, EA Baines, RAS White (2002)Post-traumatic para-ureteral urinoma (uriniferous pseudocyst) in a cat, In: VETERINARY AND COMPARATIVE ORTHOPAEDICS AND TRAUMATOLOGY15(2)pp. 123-126 SCHATTAUER GMBH-VERLAG MEDIZIN NATURWISSENSCHAFTEN
SL Parfitt, RJ Milner, ME Salute, JP Farese, NJ Bacon, FJ Bova, DA Rajon (2010)RADIOSENSTIVITY AND CAPACITY FOR RADIATION-INDUCED SUBLETHAL DAMAGE REPAIR OF CANINE TRANSITIONAL CELL CARCINOMA CELL LINES, In: JOURNAL OF VETERINARY INTERNAL MEDICINE24(3)pp. 675-675 WILEY-BLACKWELL PUBLISHING, INC
NJ Bacon, O Oni, RAS White (2002)Treatment of urethral sphincter mechanism incompetence in 11 bitches with a sustained-release formulation of phenylpropanolamine hydrochloride, In: VETERINARY RECORD151(13)pp. 373-376 BRITISH VETERINARY ASSOC
KA Kirkby, JL Wheeler, JP Farese, GW Ellison, NJ Bacon, CW Sereda, DD Lewis (2010)Surgical views: Vacuum-assisted wound closure: clinical applications., In: Compend Contin Educ Vet32(3)pp. E1-E6

Vacuum-assisted closure (VAC) is a wound management system that exposes a wound bed to local negative pressure to promote healing. Benefits of VAC therapy include removal of fluid from the extravascular space, improved circulation, enhanced granulation tissue formation, and increased bacterial clearance. VAC therapy has been used extensively in human patients to treat a variety of acute and chronic wound conditions. This article reviews the use of VAC therapy in a variety of wound conditions and describes our experiences with using VAC therapy in dogs and cats at the University of Florida.

EN Kishi, SP Holmes, JR Abbott, NJ Bacon (2014)Functional metastatic parathyroid adenocarcinoma in a dog, In: CANADIAN VETERINARY JOURNAL-REVUE VETERINAIRE CANADIENNE55(4)pp. 383-388 CANADIAN VET MED ASSOC