CROSS-CANADA DISEASE REPORT
RAPPORT DES MALADIES DIAGNOSTIQUÉES AU CANADA
Ontario Highlights of camelid diagnoses from necropsy submissions to the Animal Health Laboratory, University of Guelph, from 1998 to 2004
etween January 1, 1998, and August 31, 2004, 93 camB elids, comprising 35 llamas and 58 alpacas, were submitted for necropsy to the Guelph, Kemptville, and Ridgetown locations of the Animal Health Laboratory, University of Guelph. Table 1 shows the number of submissions by species and age group for each location.
radic diagnoses in this age group were nutritional myopathy; heat stroke; systemic bacterial infection; peritonitis, secondary to ileocecal intussusception; and perforated gastric ulcer. One 3-month-old llama with the history of having been born with marked concavity of the distal neck and having an abnormal gait and stance was found to have misshapen cervical (C)5, C7, and thoracic (T)1 vertebrae, with dorsal displacement of T1 and compressive myelopathy of the spinal cord. A congenital vertebral malformation was suspected.
Fifteen-day-old to 1-year-old camelids Lymphosarcoma was diagnosed in 1 llama and 2 alpacas aged 6 to 7 mo. The clinical course was reported as being short, only 1 to a few days in duration. The llama was 1 of 4 from the same herd that had been diagnosed with lymphosarcoma in the preceding 4 y (lymphosarcoma is reported by some authors [2] as the most commonly diagnosed neoplasm of llamas and alpacas). Other spo-
Camelids over 1 year old Digestive tract disease was the commonest diagnosis in this age group. In 1 llama and 2 alpacas that had tested negative for infection with BVDV and other viruses, erosive stomatitis was diagnosed along with mycotic gastritis in the llama and coccidiosis in the alpacas. In an alpaca that had tested negative for BVDV infection and had died while being treated for parasitic meningoencephalitis, severe subacute erosive mucosal disease was diagnosed. Gastric ulceration was a frequent diagnosis, occasionally, as the cause of death due to mycotic invasion or perforation with secondary septic peritonitis, but more commonly, as an incidental finding in animals dying from other causes. Intestinal accidents were infrequently diagnosed; they included idiopathic colon impaction and pyloric stenosis associated with pyloric fibrosis, ulceration, and bacterial infection. Neurological disease was the 2nd most common diagnosis in camelids in this group. Lesions consistent with parasitic meningoencephalitis due to “meningeal worm,” Parelaphostrongylus tenuis (3), were found in 2 alpacas and 1 llama. Some affected herds reported multiple cases of parasitic meningoencephalitis in consecutive years. Cases of polioencephalomalacia (3 alpacas), nonsuppurative encephalitis, and nonsuppurative meningoencephalitis (also in alpacas), were presumed to have been caused by a virus, but tests for rabies virus, West Nile virus, and agents of malignant catarrhal fever were negative. An alpaca with a 3-week-long history of ataxia progressing to recumbency had microscopic lesions in the spinal cord that were consistent with reported cases of degenerative myeloencephalopathy (4).
Cross-Canada Disease Report provides rapid publication of brief reports of disease trends or new diseases — maximum of 500 words and 2 references. The Report is edited but not refereed. Le Rapport des maladies diagnostiquées au Canada permet de publier rapidement un bref compte rendu sur l’évolution de certaines maladies ou sur l’apparition de nouvelles pathologies. Comptant au maximum 500 mots et 2 références, le Rapport est corrigé, mais n’est pas expédié en relecture critique.
Contributions are welcome and may be sent to: Les articles sont les bienvenus et peuvent être envoyés à l’adresse suivante : Dr. Catherine Curtis Animal Disease Research Institute Canadian Food Inspection Agency P.O. Box 640, Lethbridge, Alberta T1J 3R4 Tel.: (403) 382-5527 Fax: (403) 381 1202 E-mail:
[email protected]
Abortions For 20 of the 21 abortion submissions, no infectious etiology was found; 1 alpaca abortion was attributed to infection with bovine viral diarrhea virus (BVDV). However, 3/20 fetuses were in very thin to emaciated body condition, and 2/20 were diagnosed with fetal stress syndrome (in utero hypoxia). The dams of 2 fetuses for which no infectious cause was found for abortion had a history of systemic illness on the day before aborting. One- to 14-day-old camelids Systemic bacterial infection, usually associated with omphalitis, was a common diagnosis in neonatal crias. Developmental anomalies diagnosed in this group included renal hypoplasia in an alpaca, and multiple congenital heart defects, consisting of a ventricular septal defect and common pulmonary and aortic artery trunk, in a llama. Ventricular septal defects have been reported as “relatively common” in llamas (1). Intestinal cryptosporidiosis associated with a history of lethargy, colic, and diarrhea was diagnosed in multiple alpaca crias from 1 farm.
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Table 1. Submissions by camelid species and age group received for necropsy at the Guelph, Kemptville, and Ridgetown locations of the Animal Health Laboratory (AHL), University of Guelph between January 1, 1998, and August 31, 2004
Abortions
AHL location
Alpaca
Guelph 7 Kemptville 5 Ridgetown 2 Total 21
Llama
1 to 14 d old Alpaca
15 d to 1 y old
Llama
Alpaca
2 2 2 5 5 4 0 2 — 1 — — 9 14
Hepatic disease was the 3rd most common diagnosis. Hepatic lipidosis was the sole diagnosis in 1 adult alpaca, but it was usually found in conjunction with other diseases, such as septicemia, coccidiosis, intestinal impaction, and gastric ulceration. Parasitic hepatitis attributed to infection with Fasciola hepatica (liver fluke) was diagnosed in 1999 in an alpaca from southwestern Ontario. Sporadic diagnoses in this group included exertional myopathy, idiopathic myocardial fibrosis, cardiac ventricular septal defect, bacterial myocarditis, and cardiac tamponade, the latter condition being associated with shearing. Tumors were also diagnosed sporadically; these included granulosa cell tumor (alpaca), ruptured anaplastic (suspected adrenal cortical) carcinoma (alpaca), and stromal cell sarcoma causing mandibular osteolysis (llama).
Acknowledgment
. 1 y old
Llama 2 5 —
Alpaca
Llama
Total
13 8 41 17 11 49 — — 3 49 93
References 1. Fowler ME. Congenital and hereditary condition. In: Fowler ME, ed. Medicine and Surgery of South American Camelids, 2nd ed. Iowa State Univ Pr 1998:490. 2. Cebra CK, Garry FB, Powers BE, Johnson LW. Lymphosarcoma in 10 new world camelids. J Vet Intern Med 1995;9:381–385. 3. Krogdahl DW, Thilsted JP, Olsen SK. Ataxia and hypermetria caused by Parelaphostrongylus tenuis infection in llamas. J Am Vet Med Assoc 1987;190:191–193. 4. Morin DE, Toenniessen JG, French RA, Knight BL, Zachary JF. Degenerative myeloencephalopathy in two llamas. J Am Vet Med Assoc 1994;204:938–942.
Janet L. Shapiro, Philip Watson, Animal Health Laboratory, University of Guelph, Kemptville College Campus, Mail Bag 2005, Kemptville, Ontario K0G 1J0; Beverly McEwen, Susy Carman, Animal Health Laboratory, University of Guelph, Box 3612, Guelph, Ontario N1H 6R8.
The authors thank Holly Lethbridge for her assistance in collating data for this report.
BOOK REVIEW
Adams DR. Canine Anatomy: A Systemic Study, 4th ed. Iowa State Press, Ames, Iowa, USA, 2004. ISBN 0-8138-1281-X. US$101.50. not very excited about this book, but then it isn’t meant for me. There are many excellent anatomy books that give information on Itheam dog; among them Textbook of Veterinary Anatomy by Dyce, Sack,
and Wensing, Miller’s Anatomy of the Dog by Evans and Christensen, and Miller’s Guide to the Dissection of the Dog by Evans and deLahunta. So why do we need another one? The answer perhaps lies in a remark made to me recently by a first year student who said she was finding Dyce, Sack, and Wensing really tough going. I remonstrated with her, pointing out that it was a very good and comprehensive book and, moreover, that it omitted unnecessary detail and set much information in an obvious clinical context. Her response, “But we aren’t ready for that yet.” She was not alone. It is undoubtedly true that many students enter veterinary colleges today with remarkably little knowledge of morphology. Some also find the nontechnical vocabulary and ordinary sentence structure of many anatomy texts challenging. Adams’ book is here to help. Canine Anatomy: A Systemic Study is an atlas with a simple commentary arranged around the figures in lieu of extensive captions. The everyday language is straightforward and there aren’t very many cross references to physiology, histology, or clinical conditions, though there are some. There are occasional comparative notes on the cat. This is anatomy, pure and simple. Or it would be if the author could resist those little anatomical conceits like calling the hindpaw the pes, and the hindleg the pelvic limb. The author goes to some lengths to make the introduction to anatomical terminology as painless as possible. When terms first appear, they are in bold capitals and are often followed by an explanation in parenthesis. These vary according to need, but they may include a rather
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idiosyncratic guide to pronunciation, the singular or plural, and perhaps a tentative etymology or a useful synonym. I suspect that some tempting synonyms, such as mitral valve for left atrioventricular valve, and oviduct for uterine tube, have been deliberately omitted. Many students would find Adams’ approach to terminology very helpful, but I can’t help bridling at something that can be called either the du” o-de’num or the du-od’e-num, and it took me a moment to figure out what the pre’ pyoos might be. The illustrations are simple, black and white, line drawings and most are good, though some are undistinguished and others are copies of classic diagrams presented without acknowledgment. Clearly several artists have been involved and I like the fact that some were students. It is certainly true that many first year students prefer line drawings to photographs, or beautiful professional illustrations, because they are simple to interpret, contain less information, and are easier to reproduce. This is perhaps a little sad, but we should remember that Adams’ book is intended only as a start on a lifelong journey. It is a fundamentally sound start. As the title makes clear, the text is arranged by system, and I was very interested to note that it is intended to accompany rapid dissection of each system in fresh specimens. I like this idea, especially where large numbers of dogs are inevitably euthanized by a local humane society. Many students will find this book very helpful, particularly those who have little prior experience of anatomy. If it were cheaper, perhaps a paperback, I could recommend it with more enthusiasm. Reviewed by Peter Flood, Emeritus Professor, BVSc, MSc, PhD, MRCVS, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4. Can Vet J Volume 46, April 2005
