From 2006 through March of 2011, ADDL received over 200 accessions with a pathology assignment from alpaca cases. A review of these cases should provide useful information for practitioners treating New World camelids.
The most common conditions involved the digestive system, accounting for 34% of alpaca cases submitted to ADDL. Oral diseases recognized included ulcerative stomatitis, glossitis and tooth root abscesses. Tooth root abscesses are fairly common in these animals and generally present as mandibular swelling (1).
Gastritis of undetermined cause, as well as mycotic gastritis, was observed. Ulceration of the third gastric compartment was diagnosed in six cases. Such ulcers have been described in llamas and are often seen in combination with other disease conditions or associated with stress (2). One case of grain overload was also diagnosed.
Gastrointestinal parasitism was quite common and included nematodiasis (most often Hemonchus sp. and Trichuris sp., coccidiosis, cestodiasis and cryptosporidiosis. Nonspecific enteritis was diagnosed in six cases. Other intestinal problems included small intestinal and ileocecal intussusceptions, enterolithiasis and colonic rupture.
There were two cases of mesenteric abscess and one each of peritonitis and hemoabdomen. Hepatic lipidosis was the most common liver lesion along with additional cases of hepatic necrosis, cholangiohepatitis and nonspecific hepatitis.
Reproductive disease accounted for 15% of alpaca submissions. Most of these represented abortion where no etiology was determined. Streptococcus sp. and Enterobacter sp. were isolated from cases of placentitis. Individual cases of abortion were attributed to infection with Encephalitozoon sp. and Toxoplasma sp. One case of abortion was due to a twin pregnancy and two cases of dystocia were diagnosed. No definitive cause for neonatal death was found in most cases. Colibacillosis and bronchopneumonia were determined to be causes of neonatal death in one case each.
Septicemia accounted for 8% of alpaca submissions. Bacterial isolates included Klebsiella sp., E. coli, Streptococcus sp. and Aeromonas sp. One animal had West Nile virus infection.
Respiratory system diseases were found in another 8% of cases. Rhinitis was attributed to both bacterial and mycotic agents. Lipid pneumonia was considered an incidental finding in one case. Aspiration pneumonia was the most common form of pneumonia. No agent was isolated from cases of pneumonia, bronchopneumonia and pulmonary granulomas in six cases. Serratia sp. and Klebsiella sp. were isolated from one case each of bronchopneumonia. One case of pulmonary fibrosis was also diagnosed.
Cases involving the nervous system involved 6% of alpacas submitted to ADDL. One case each of polioencephalomalacia and cerebellar abiotrophy were diagnosed. Listeria sp. was isolated from a single case of meningitis. One case of mycotic meningoencephalitis and three cases of eosinophilic meningoencephalitis were found. No etiologic agent was isolated from other cases of encephalitis, meningitis and meningoencephalitis. Encephalitis meningoencephalitis in camelids has been associated with Parelaphostrongylus tenuis infection, but no nematodes were observed in the ADDL cases (3). There also was a single case of otitis externa and media.
Congenital defects in young alpacas accounted for 6% of diagnoses. The most common defect was choanal atresia with six cases. This congenital defect has been reported to be common in both alpacas and llamas (4). Cardiac defects that were diagnosed included two ventricular septal defects, one atrial septal defect and one case of dextroposition of the aorta. Single incidents of epiglottal hypoplasia, vulvar atresia and ectopic ureter were also identified.
The integumentary system was involved in 5% of cases. Nonspecific dermatitis was the most common diagnosis. One case each of demodectic mange and one of nonspecific mange were found. Two alpacas had dermatophytosis and one had a cutaneous abscess.
Approximately 4% of alpaca cases were diagnosed as neoplastic disease. Lymphosarcoma was the most common type of neoplasia found. Other tumors included fibropapilloma, jejunal adenocarcinoma, undifferentiated malignant neoplasm of mandible and spindle cell sarcoma.
Musculoskeletal disease was found in nearly 3% of alpaca samples submitted. Observed conditions included patellar luxation, intervertebral disc disease, vertebral fracture and osteomyelitis.
An equal number of cases involved the urinary system. Nephritis and pyelonephritis were the diagnoses.
Two cases of cardiomyopathy were diagnosed in alpacas; one each of the dilated and hypertrophic types.
Other diagnoses included emaciation, copper deficiency, and splenic rupture. No diagnostic lesions were identified in about 11% of alpaca submissions.
As can be seen from these laboratory findings, alpacas have a wide variety of medical problems that are not dissimilar from those of small ruminants. Gastrointestinal disease and parasitism were the most commonly observed problems at ADDL with reproductive and congenital problems also accounting for significant losses to alpaca producers.
References
- Niehaus AJ and Anderson DE: 2007. Tooth root abscesses in llamas and alpacas: 123 cases (1994-2005). JAVMA 231:284-289.
- Smith BB, Pearson EG and Timm KI: 1994. Third compartment ulcers in the llama. Vet Clin North Am Food Anim Prac 10 (2):319-330.
- Johnson AL, Lamm CG, Divers TJ: 2006. Acquired cervical scoliosis attributed to Paralaphostrongylus tenuis infection in an alpaca. JAVMA 229:562-5.
- Whitehead CE: 2009. Management of neonatal llamas and alpacas. Vet Clin North Am Food Anim Prac 25:353-366.