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South American camelids (SACs) have become increasingly popular as livestock and companion animals in the Midwestern United States. With increased ownership, postmortem evaluations and samples available for diagnostic assessment are being submitted more frequently to veterinary diagnostic laboratories. We searched archived pathology records at the Wisconsin Veterinary Diagnostic Laboratory (WVDL) between 2009–2019 for SAC cases. Postmortem records from 166 alpacas and 27 llamas were included, with an average of 1.42 diagnoses per animal. The overall average diagnostic rate was 79.8%. Abortion and neonatal cases (fetus to 1-wk-old) had the lowest diagnostic rate (33.3%) and was the only group with a diagnostic rate statistically significantly lower than the average. The most common diagnoses were gastrointestinal parasitism and suboptimal nutritional status or inanition; 78% of cases diagnosed with suboptimal nutritional status were also parasitized. The gastrointestinal parasites identified most frequently were Eimeria sp. and strongyles, especially Nematodirus sp. Our findings may aid allocation of diagnostic resources to better serve regional SAC populations and provide a framework for practitioners who send samples to laboratories for analysis. Submission of whole bodies, euthanized animals, fresh tissue, and inclusion of placental tissues in abortion cases are recommended for optimal diagnostic outcome.

A 19-year-old male castrated llama presented with a 3-year history of tooth root abscesses and an osseous mass on the left mandible. Surgical excision of the affected teeth and mass was performed, and histopathologic review indicated that the mass was an oral squamous cell carcinoma. The patient was admitted to the hospital again 4 months later in severe respiratory distress with submandibular edema, and bicavitary effusion. Necropsy results revealed regional and distant metastatic squamous cell carcinoma.

Several plants that contain indolizidine alkaloids, including swainsonine, are toxic to livestock, causing dysfunctional lysosomes and storage disease. Swainsonine induces a neurovisceral disease, known as locoism, in sheep, goats, and cattle, which occurs in several parts of the world, including, but not limited to, the western United States, China, and parts of Australia. In South America, locoism has been described in the Andean region of Argentina affecting sheep, cattle, and llamas. Intoxication by consumption of Astragalus punae was suspected in 4 llamas in Jujuy Province, northwestern Argentina. The grazing area contained abundant specimens of A. punae. The clinical course was ~15 d, and included moderate ataxia, incoordination of hindlimbs, and progressive loss of body condition. Microscopically, fine cytoplasmic microvacuolation was observed in the proximal convoluted renal tubules. Ultrastructurally, these changes consisted of severely dilated lysosomes. Swainsonine was detected in stem and leaf samples of A. punae at a concentration of 0.06%. Based on clinical history and signs, histologic and ultrastructural changes, and plant analysis, a diagnosis of swainsonine toxicosis caused by consumption of A. punae was made, which has not been reported previously, to our knowledge.

Ulcers of the oral cavity, esophagus, and gastric compartments of South American camelids are uncommon. Multifocal-to-coalescing ulcers were identified in the oral cavity, esophagus, and/or gastric compartments of 5 alpacas submitted for postmortem examination. Fusobacterium necrophorum was isolated from the lesions in all alpacas, in combination with other aerobic and anaerobic bacteria. In 4 of these cases, F. necrophorum–associated lesions were considered secondary to neoplasia or other chronic debilitating conditions; in 1 case, the alimentary ulcers were considered the most significant autopsy finding. It is not known if this agent acted as a primary or opportunistic agent in mucosal membranes previously damaged by a traumatic event, chemical insult, immunodeficiency, or any other debilitating condition of the host.

Lysosomal storage diseases are inherited and acquired disorders characterized by dysfunctional lysosomes. Intracytoplasmic accumulation of undegraded substrates leads to impaired cellular function and death. Several plant species are toxic to livestock because of the presence of indolizidine alkaloids, including swainsonine, which cause a storage disease. Swainsonine-induced nervous disease (i.e., locoism) of sheep and cattle is well recognized in several parts of the world, particularly in the western United States and in parts of Australia. Spontaneous intoxication by Astragalus garbancillo var. garbancillo was suspected in a group of 70 llamas (Lama glama) in Jujuy Province, northwestern Argentina. The animals grazed an area dominated by stands of A. garbancillo var. garbancillo. Clinical signs were staggering, ataxia, hypermetria, and progressive weight loss. The clinical course in individual animals was ~50 d. The main microscopic changes were Purkinje cell degeneration, necrosis, and loss, associated with intracytoplasmic vacuolation, meganeurite formation, and Wallerian degeneration. Specific positive labeling for ubiquitin was observed in axonal spheroids. Composite leaf and stem samples of A. garbancillo var. garbancillo analyzed by high-performance liquid chromatography contained 0.03% swainsonine. Based on the microscopic lesions, clinical history, and plant analysis, a diagnosis was made of storage disease caused by consumption of swainsonine-containing A. garbancillo var. garbancillo. EEA Salta Fil: Marín, Raúl E. Universidad Nacional de Jujuy. Facultad de Ciencia Agrarias; Argentina. Fil: Micheloud, Juan Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta. Área de Sanidad Animal; Argentina. Fil: Vignale, Nilda D. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina. Fil: Gimeno, Eduardo Juan. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Cátedra de Patología General;Argentina. Fil: O'Toole, Donal. Wyoming State Veterinary Laboratory ; Estados Unidos Fil: Gardner, Dale R. USDA-ARS Poisonous Plant Research Laboratory; Estados Unidos Fil: Woods, Leslies. University of California–Davis. California Animal Health and Food Safety Laboratory System; Estados Unidos Fil: Uzal, Francisco A. University of California–Davis. California Animal Health and Food Safety Laboratory System, San Bernardino; Estados Unidos

Listeriosis is a disease of humans and domestic mammals (mainly ruminants) with variable manifestations, primarily encephalitis, septicemia, and abortion. Although Listeria monocytogenes readily causes illness in ruminants, the prevalence among domestic South American camelids (llamas and alpacas) is low and has not been documented in their wild counterparts, the vicuna and guanaco. We describe herein the clinical signs, autopsy findings, and histopathology of septicemia and suppurative meningoencephalitis caused by L. monocytogenes in 2 neonatal llamas ( Llama glama) from the same herd. L. monocytogenes was isolated in pure culture and identified by real-time PCR on fresh and paraffin-embedded tissue samples of the brain from both crias. This presentation of septicemic listeriosis with meningoencephalitis in 2 animals from the same group is unusual, especially among llamas.

An 18-y-old female llama ( Lama glama) in Saskatoon, Saskatchewan was examined during a routine herd check, and a mass was detected in the ventral cervical area just below the angle of the jaw. No clinical signs were evident except for the mass and chronic loss of body condition. Postmortem examination revealed bilateral enlargement of the thyroid gland with multiple cysts. Histopathology of the thyroid gland revealed follicular compact-cellular carcinoma lesions, with infiltration of neoplastic thyroid follicular cells in regional lymph nodes.

A 9-year-old, intact female alpaca ( Vicugna pacos) was presented for a second opinion with a 1-year history of nonpruritic, multifocal scaling and crusted cutaneous lesions, mainly involving skin on the face, axillae, and ventral abdomen. Clinical abnormalities were limited to the skin, and the alpaca was otherwise healthy. The initial veterinarian had examined the alpaca, found no evidence of ectoparasites with laboratory testing, and had tried several trial therapies including oral antibiotics, ivermectin, and topical use of betadine solution. At the time of presentation, the lesions had neither improved nor worsened with any attempted therapy, and multiple skin biopsies were collected. Histopathology and immunohistochemical staining findings were consistent with the pagetoid reticulosis type of cutaneous epitheliotropic T-cell lymphoma. Our report describes the clinical, histopathologic, and immunophenotypic features of pagetoid reticulosis epitheliotropic cutaneous T-cell lymphoma in an alpaca.

Coccidioidomycosis is a fungal disease caused by either Coccidioides immitis or Coccidioides posadasii. Anecdotal evidence suggests that camelids are particularly susceptible to this disease and that a relatively large percentage of pneumonias in these animals are caused by Coccidioides spp. In a search of 21 y (1992–2013) of records from the California Animal Health and Food Safety Laboratory, we found 79 cases of coccidioidomycosis diagnosed in camelids; 66 (84%) had pneumonia and 13 (16%) had lesions only in organs other than the lungs. The organs most frequently affected were lung (84%) and liver (78%). Coccidioides spp. were the cause of pneumonia in 66 of 362 (18%) camelid cases during the study period. The lesions in affected organs were multifocal-to-coalescing pyogranulomas, which in most cases were visible grossly. Ten of the 12 formalin-fixed, paraffin-embedded lung samples tested by a universal Coccidioides spp. PCR assay were positive (4 C. immitis, 2 C. posadasii); the species could not be determined in 4 of the 10 cases positive by PCR. Coccidioidomycosis is an important cause of pneumonia in camelids in California, and can be caused by either C. immitis or C. posadasii.

Bluetongue virus (BTV) is a vector-transmitted pathogen that typically infects and causes disease in domestic and wild ruminants. BTV is also known to infect domestic canines as discovered when dogs were vaccinated with a BTV-contaminated vaccine. Canine BTV infections have been documented through serological surveys, and natural infection by the Culicoides vector has been suggested. The report of isolation of BTV serotype 11 (BTV-11) from 2 separate domestic canine abortion cases in the states of Texas in 2011 and Kansas in 2012, were apparently unrelated to BTV-contaminated vaccination or consumption of BTV-contaminated raw meat as had been previously speculated. To elucidate the origin and relationship of these 2 domestic canine BTV-11 isolates, whole genome sequencing was performed. Six additional BTV-11 field isolates from Texas, Florida, and Washington, submitted for diagnostic investigation during 2011 and 2013, were also fully sequenced and analyzed. The phylogenetic analysis indicates that the BTV-11 domestic canine isolates are virtually identical, and both share high identity with 2 BTV-11 isolates identified from white-tailed deer in Texas in 2011. The results of the current study further support the hypothesis that a BTV-11 strain circulating in the Midwestern states could have been transmitted to the dogs by the infected Culicoides vector. Our study also expands the short list of available BTV-11 sequences, which may aid BTV surveillance and epidemiology.

Formalin-fixed, paraffin-embedded tissues from elk ( Cervus elaphus), goats, and camelids with case histories and lesions suggestive of Parelaphostrongylus tenuis were examined by histology to characterize lesions that could aid in definitively diagnosing P. tenuis infection. Additionally, sections of paraffin-embedded tissue were used in a nested polymerase chain reaction (nPCR) using Parelaphostrongylus-specific primers to determine how PCR results corresponded with histological findings. Histological changes in brain and spinal cord consisted of linear tracks of hemorrhage; tracks or perivascular accumulations of hemosiderin-laden macrophages; acute foci of axonal degeneration and/or linear glial scars; and perivascular, parenchymal, or meningeal accumulations of eosinophils and/or lymphocytes and plasma cells. Of the 43 samples with histologic lesions consistent with neural larval migrans, 19 were PCR positive; however, only 8 were confirmed Parelaphostrongylus by DNA sequencing. Additionally, 1 goat was identified with a protostrongylid that had a 97% identity to both Parelaphostrongylus odocoilei and a protostrongylid nematode from pampas deer ( Ozotoceros bezoarticus celer) from Argentina. None of the histologic lesions individually or in combination correlated statistically to positive molecular tests for the nematode. The results indicate that it is possible to extract Parelaphostrongylus DNA from formalin-fixed, paraffin-embedded tissue, but extended fixation presumably can cause DNA crosslinking. Nested PCR provides another diagnostic tool to identify the cause of neurologic disease in camelids and elk with histologic lesions consistent with neural larval migrans. Furthermore, potential novel protostrongylid DNA was detected from a goat with lesions consistent with P. tenuis infection, suggesting that other neurotropic Parelaphostrongylus species may occur locally.

The schistosome Heterobilharzia americana infects several mammalian species in the southeastern United States, including horses, but infections have not been reported in camelids. This is a report of H. americana infection in a 6-year-old llama with extensive cardiac pathology and congestive heart failure. Parasite-induced granulomas were widely disseminated and included overwhelming involvement of the lungs and liver. Microscopic lesions in the heart included myofiber degeneration and necrosis, with extensive replacement fibrosis. Polymerase chain reaction amplification and sequencing confirmed the presence of H. americana in the lungs.

It was hypothesized that acute postnatal Bovine viral diarrhea virus 1 (BVDV-1) infection leads to leukopenia and lymphoid depletion of gut-associated lymphoid tissues similar to acute disease in calves. The objectives of the current study were to characterize the pathologic effects, viremia, viral shedding, and viral antigen deposition in 6–24-month-old, acutely infected alpacas following experimental infection with noncytopathic BVDV-1 subgenotype 1b (BVDV C0-6). The BVDV-1 isolate was obtained from a cria with naturally occurring persistent infection. Lymphocytopenia occurred 3–7 days postinfection, with a 50% reduction in peripheral lymphocytes in infected alpacas. Depletion of B-cell populations in gut-associated lymphoid tissues was evident microscopically. Populations of T cells in parafollicular zones and in nodular aggregates along the superficial submucosa remained intact. The BVDV antigen was deposited most consistently in submucosal gastrointestinal aggregated lymphoid tissues of ileum, proximal colon, and stomach compartment three. Viral antigen was more variably evident in other lymphoid tissues. Antigen distribution correlated well with histologic lesions in gastrointestinal aggregated lymphoid tissues, confirming the role of virus in lymphoid depletion. Nasal shedding was detected in all challenged alpacas on day 6 and in 4 out of 12 challenged alpacas on day 9. Viremia was present as early as day 3, and present in all challenged alpacas on days 5, 6, 7, and 9 postchallenge. Lymphocytopenia and depletion of gastrointestinal aggregated lymphoid tissues associated with acute BVDV-1 infection likely results in immune compromise and is expected to exacerbate concurrent infections even though uncomplicated BVDV-1 infection was clinically unapparent.

Fusobacterium necrophorum, a Gram-negative, anaerobic bacterium, is an opportunistic animal and human pathogen that causes a variety of infections termed necrobacillosis. There are 2 subspecies of F. necrophorum (subsp. necrophorum and subsp. funduliforme) that differ morphologically and biochemically and in virulence. Leukotoxin, a secreted protein, is considered to be the major virulence factor. In camelids, F. necrophorum causes a variety of infections, generally involving the lips, tongue, pharynx, interdigital spaces, foot pad, larynx, mandible, or maxillary bones. The objective of the current study was to characterize the presumptive Fusobacterium isolates from a variety of necrotic infections in llama ( Lama glama) and alpaca ( Vicugna pacos) and determine whether the strains possess leukotoxin activities. A total of 7 isolates from alpaca and 2 isolates from llama were characterized. Based on growth characteristics in broth culture, and biochemical and polymerase chain reaction analyses, all 9 isolates belonged to subsp. necrophorum and possessed the putative hemagglutinin gene. Western blot analysis with antileukotoxin antibodies raised in rabbit showed the presence of leukotoxin protein in the culture supernatant of all isolates. Furthermore, flow cytometry of the culture supernatants demonstrated cytotoxicity to bovine and alpaca polymorphonuclear leukocytes (PMNs). The extent of cytotoxicity to either alpaca or bovine PMNs differed among camelid strains. The cytotoxicity of many of the camelid strains was higher ( P < 0.05) toward alpaca PMNs compared to bovine PMNs. Fusobacterium necrophorum isolates from llama and alpaca are similar to bovine isolates, and leukotoxin may be a major virulence factor.

Lymphoma and/or leukemia was diagnosed in 26 camelids (20 alpacas and 6 llamas) out of 110 camelid neoplasia archived January 1995 through January 2012 at the Colorado State Veterinary Diagnostic Laboratories (CSU-VDL). Some of the tumors presented a diagnostic challenge because they could not be distinguished on the basis of gross or microscopic morphology. Immunohistochemistry using a T-cell marker (cluster of differentiation [CD]3), a B-cell marker (paired box protein [PAX]-5), a leukocyte integrin beta-2 marker (CD18), and a neuroendocrine marker (synaptophysin) was employed to help differentiate between lymphoma and other malignant round cell tumors. Alpaca lymphomas presented as either juvenile disseminated lymphoma in crias ≤2 years of age ( n = 8) or adult multicentric lymphoma and/or leukemia ( n = 12). Lymphomas in alpacas were of T-cell origin ( n = 13), non–B-cell, non–T-cell origin ( n = 4), B-cell origin ( n = 2), or myelogenous leukemia ( n = 1). Abdominal organs, predominantly the liver, were commonly involved in both the crias and adult alpacas. Lymphomas in llamas presented as either adult multicentric lymphoma of B-cell origin in animals younger than 7 years of age ( n = 2), or T-cell lymphoma ( n = 2), and non–B-cell, non–T-cell lymphoma ( n = 1) in animals 7 years of age or older. The thorax was commonly involved in llamas, with infiltration of neoplastic cells into hilar and mediastinal lymph nodes. A rare type of lymphoma diagnosed in the llamas was cutaneous, epitheliotrophic T-cell lymphoma ( n = 1).

Measurement of serum immunoglobulin G (IgG) is used for the assessment of passive transfer of immunity in neonatal crias, with an IgG concentration 60%), whereas the IT2 standard consisted of beta and gamma globulins. The discrepant results between assays IT1 and IT2 were eliminated when the same standard was used (IT1: median 11 g/l; IT2: 10 g/l; n = 19 and 17, respectively). The IT1 assay had the highest precision, while the RID assay had the lowest. The results indicate that camelid IgG measurement is highly dependent on the assay standard and is not directly comparable between assays, potentially resulting in underdiagnosis of FPT in some crias.

Aberrant migration of Parelaphostrongylus tenuis in camelids results in neurologic deficits, recumbency, and sometimes death. An antemortem diagnosis of P. tenuis in camelids is typically based upon the presence of characteristic asymmetric neurologic deficits, known exposure to white-tailed deer, cerebrospinal fluid (CSF) eosinophilia, and response to treatment. The diagnostic accuracy of CSF eosinophil percentage for the diagnosis of P. tenuis in camelids has not been critically examined. The objective of the current study was to determine the sensitivity (Se) and specificity (Sp) of CSF eosinophil percentage, CSF eosinophil concentration, total nucleated cell concentration, and protein concentration for the antemortem diagnosis of P. tenuis. Medical records of camelids admitted to Cornell University with clinical signs of neurologic disease, CSF analysis, and necropsy were examined from January 2000 through December 2009. Se and Sp were determined by receiver operating characteristic curves in camelids diagnosed with P. tenuis ( n = 13) or other conditions ( n = 24) based on postmortem examination. More than 17% of eosinophils in CSF had a Se of 85% and Sp of 92% for P. tenuis diagnosis (area under the curve [AUC]: 0.87; SE AUC: 0.07; P < 0.0001; 95% confidence interval [CI] AUC: 0.72–0.96), and >1.4 eosinophils/µl of CSF had a Se of 85% and Sp of 96% (AUC: 0.9; SE AUC: 0.06; P < 0.0001; 95% CI AUC: 0.76–0.97). Cerebrospinal fluid eosinophil percentage and concentration are sensitive and specific methods for diagnosing P. tenuis antemortem in camelids residing in regions endemic to white-tailed deer.

Adenovirus-associated enteritis was diagnosed by histopathology of small intestine in a 2-year-old alpaca ( Vicugna pacos). Electron microscopy confirmed intracytoplasmic and intranuclear adenoviral particles within enterocytes. Nucleic acid was extracted from paraffin-embedded tissue sections, and a pan-adenovirus nested polymerase chain reaction (PCR) assay was employed to target a partial sequence of the polymerase gene. The PCR product (321 bp) was cloned and sequenced. Comparison of the nucleotide sequence against the National Center for Biotechnology Information (NCBI) nucleotide database demonstrated 68% identity with the isolates Canine adenovirus 1 and Bovine adenovirus 3. Comparison of the predicted amino acid sequence against the NCBI database demonstrated 75% identity with Bovine adenovirus 3. Phylogenetic analysis supported the relatively close relationship of this isolate to Bovine adenovirus 3, but the alpaca isolate was sufficiently distant to be considered a potentially novel adenovirus for this species.

Two cases of pulmonary vascular anomaly in unrelated adult alpacas ( Vicugna pacos) are described. In the first case, a 9-year-old intact male alpaca presented at Oregon State University Veterinary Teaching Hospital with bilateral epistaxis and died the subsequent day following severe hemorrhage from the mouth and nostrils. At necropsy, a tortuous vascular lesion was identified in the right cranial lung lobe, associated with hemorrhage into airways. In the second case, a 2-year-old female alpaca presented with postpartum anorexia, opisthotonus, and recumbency. In this second case, a similar vascular lesion was identified in the right cranial lung lobe but without associated hemorrhage. Histopathological examination of the lesion in both cases revealed numerous dilated, irregular blood vessels with marked variation in wall thickness within vessels, surrounded by foci of extramedullary hematopoiesis. Diagnoses of locally extensive pulmonary vascular anomalies (arteriovenous malformations) were made.

Bluetongue is a vector-borne viral disease that affects domestic and wild ruminants. The epidemiology of this disease has recently changed, with occurrence in new geographic areas. Various real-time quantitative reverse transcription polymerase chain reaction (real-time qRT-PCR) assays are used to detect Bluetongue virus (BTV); however, the impact of biologic differences between New World camelids and domestic ruminant samples on PCR efficiency, for which the BTV real-time qRT-PCR was initially validated are unknown. New world camelids are known to have important biologic differences in whole blood composition, including hemoglobin concentration, which can alter PCR performance. In the present study, sheep, cattle, and alpaca blood were spiked with BTV serotypes 10, 11, 13, and 17 and analyzed in 10-fold dilutions by real-time qRT-PCR to determine if species affected nucleic acid recovery and assay performance. A separate experiment was performed using spiked alpaca blood subsequently diluted in 10-fold series in sheep blood to assess the influence of alpaca blood on performance efficiency of the BTV real-time qRT-PCR assay. Results showed that BTV-specific nucleic acid detection from alpaca blood was consistently 1–2 logs lower than from sheep and cattle blood, and results were similar for each of the 4 BTV serotypes analyzed.

A 14-year-old female alpaca ( Vicugna pacos) was presented with a 1-week history of lethargy and anorexia and a 2-day history of recumbency, trembling, and hypothermia. There were no significant gross findings on postmortem examination. Hematoxylin and eosin–stained sections of brain demonstrated the presence of intracytoplasmic crystalline eosinophilic rod-shaped inclusions, mainly in the hippocampal pyramidal cells. Immunohistochemical staining for synuclein, tau protein, ubiquitin, and smooth muscle actin was negative. All inclusions were positive with phosphotungstic acid hematoxylin. Ultrastructurally, the inclusions were multilamellar and filamentous with longitudinal herringbone pattern and cross-sectional latticelike structure. The combination of hematoxylin and eosin appearance, special stains, immunostaining, and ultrastructural findings was consistent with Hirano-like bodies. The Hirano-like bodies were highly unlikely to be the cause of the neurologic signs experienced by this alpaca. To the authors' knowledge, this is the first report of spontaneous cerebral Hirano-like bodies in an alpaca.

The microanatomy of healthy skin from 12 different body sites was investigated in 14 alpacas ( Vicugna pacos). The microanatomy of alpaca skin is typical of domestic animal skin in general, and closely resembles that from llamas.

Malignant round cell neoplasia was identified in 12 llamas and 12 alpacas aged 0–23 years. Mean age of affected alpacas (3.1 years) was significantly less than that of affected llamas (8.0 years). Tumor cell morphology varied from large and often pleomorphic (11 tumors) to small and often homogeneous (13 tumors). Neoplastic lesions were multicentric in 12 cases. Other sites were gastric (5 cases), intra-abdominal (perirenal; 4 cases), intrathoracic (2 cases), and cervical (1 case). Immunohistochemistry with antibodies to CD79α, BLA36, and CD3 identified B-cell lymphoma (12 cases) and T-cell lymphoma (6 cases). Six tumors did not express any lymphoid marker and were further immunostained for neuron-specific enolase (NSE), synaptophysin, S-100, glial fibrillary acidic protein (GFAP), and chromogranin A. All 6 of these tumors were negative for GFAP and chromogranin A but expressed 1 or more of the neural markers NSE, synaptophysin, and S-100 and were classified as primitive malignant round cell tumors (PMRCT). Tumor types could not be distinguished on the basis of animal age, gross pathologic appearance, tumor morphology, or tumor location. All animals with lymphoma and 5 with PMRCT died or were euthanatized. One alpaca with a focal cervical PMRCT lived for at least 20 months after diagnosis. Results of this study indicate that malignant round cell tumors in llamas and alpacas are a heterogeneous group that cannot be distinguished on the basis of signalment, postmortem findings, or routine light microscopic findings. Immunohistochemistry is a valuable diagnostic procedure when evaluating malignant round cell neoplasia in llamas and alpacas.

A case of malignant melanoma in a 7-year-old, intact, black, male Huacaya alpaca with a history of a chronic, nonhealing wound involving the left external nostril, weight loss, and inappetence is described. Malignant melanoma was diagnosed by histology of punch biopsy specimens from a mass on the maxilla associated with the nonhealing wound and from a mass in the submandibular region. The alpaca was humanely euthanized 10 days after the diagnosis on the basis of the poor prognosis and rapid clinical deterioration. At postmortem examination, the alpaca had an ulcerated, multilobulated, black pigmented mass (8.0 cm × 6.0 cm × 4.0 cm) that infiltrated the left rostral maxilla extending into the marrow space and into the left nasal cavity. Numerous, discrete, coalescing masses were present in the subcutaneous tissue of the submandibular area, peritracheal connective tissue, pericardium, and diaphragmatic parietal pleura and were disseminated throughout the pulmonary parenchyma. The masses were diffusely black on cut surface and exuded black pigment. Histologically, all masses were composed of spindloid to polygonal cells with indistinct cell borders and moderate amounts of cytoplasm that contained abundant fine, black granules (melanin), confirming metastasis of a primary mucocutaneous melanoma. To the authors' knowledge, this is the first report of a malignant melanoma involving bone in a New World camelid.

A 2-month-old female llama with a history of tetraparesis was presented for necropsy. This cria was apparently normal until it became ataxic during its second week of life. It had diminished flexor reflexes of the left forelimb and both hind limbs. Hematology and serum biochemistry revealed neutrophilia, elevated alkaline phosphatase, elevated phosphorus, and modest hyperglycemia. Radiography of the cervical spine demonstrated an abnormal C3–C4 intervertebral disc and bony proliferation of the vertebral end plates. The llama was treated with antibiotics and corticosteroids but failed to respond. Postmortem examination revealed cervical intervertebral disc disease and vertebral exostosis. Microscopically, there was necrosis of intervertebral connective tissue and focal malacia of the spinal cord. Pseudomonas aeruginosa was isolated from the intervertebral disc space and from cerebrospinal fluid. To the authors' knowledge, this is the first description of Pseudomonas-associated discospondylitis in a llama.

Placentitis, premature birth, and perinatal death were associated with Encephalitozoon cuniculi infection in an alpaca. Histologically, chorionic trophoblasts contained many Gram-positive, period acid-Schiff positive, variably acid-fast spores. Multifocal necrosis and infiltration by lymphocytes, eosinophils, and neutrophils were scattered throughout the chorionic membrane. Spores in trophoblasts were approximately 1 μm X 2 μm, thick-walled, and contained polar filaments and polar vacuoles consistent with microsporidia. The presence of E. cuniculi DNA was confirmed by sequencing the polymerase chain reaction amplicon from frozen placental tissue. A few glial nodules were scattered throughout the cerebrum, and mild lymphocytic inflammation was present in the heart, liver, and lung. No organisms were detected in tissues other than the placenta. This is the first reported case of E. cuniculi infection in an alpaca.

A 13-year-old female llama was presented to the referring veterinarian for swelling and firmness of the right rear mammary gland, for a duration of 2 months, which had been unresponsive to antibiotics. A formalin-fixed wedge biopsy specimen from the affected quarter was submitted to Purdue University Animal Disease Diagnostic Laboratory for histopathology. Histopathologic examination revealed tubulopapillary acinar or solid nest-like clusters of neoplastic epithelial cells surrounded by whorls and sheets of proliferative myoepithelial cells. Histologic criteria for malignancy observed in neoplastic epithelial cells included marked cellular and nuclear atypia, high mitotic index, and numerous bizarre mitoses. The presence of osseous metaplasia in the proliferative mesenchymal component justified classification as a mixed tumor. Positive immunohistochemical staining of neoplastic epithelial cells with anticytokeratin antibody, and proliferative spindloid cells with antiviemtin and antismooth muscle actin antibodies supported the histopathologic diagnosis. The llama was in good health after about 1 year of initial presentation, and metastasis to regional lymph nodes was not reported. Mammary neoplasia is rare in camelids. To the authors' knowledge, this is the first report of a carcinoma in a mixed mammary tumor in a llama.

Reported clinical signs of coccidiosis in South American camelids include anorexia of a few days duration, sudden death, and diarrhea. Antemortem diagnosis of clinical coccidiosis is usually based on clinical signs and supported by detection of coccidial oocysts in feces. This report describes 2 atypical cases of coccidiosis in South American camelids that had no coccidial oocysts detected on antemortem fecal flotation, prolonged weight loss, and normal fecal consistency.

A 12-year-old intact female llama was euthanized following acute onset of spastic tetraparesis and recumbency with inability to rise. Postmortem examination revealed caudal cervical spinal cord compression due to a mass within the ventral spinal canal arising from the C6–C7 intervertebral disk space and attached to an irregularly thickened annulus fibrosis. On histopathologic examination, the mass was composed of amorphous acellular basophilic to amphophilic material admixed with irregularly arranged collagen bundles. The amorphous material was metachromatic and contained multiple small foci of markedly vacuolated round cells, characteristic of origin from the nucleus pulposus. Severe necrosis of all white matter tracts with astrocytic reaction was present in the overlying spinal cord segment. Ascending and descending Wallerian degeneration and dissecting interstitial astrogliosis were present within white matter tracts above and below the lesion, respectively. The diagnosis was compressive myelopathy due to chronic extrusion of the nucleus pulposus of the C6–C7 inter-vertebral disk. To the authors' knowledge, this is the first report of intervertebral disk disease in a camelid.

An alpaca herd in eastern Ontario experienced vague signs of illness, including anorexia and lethargy in 9 animals, 2.5 months after the addition of a chronically ill cria and his dam to the farm. Subsequently 2 alpaca had early pregnancy loss; one aborted at 5.5 months gestation and the other at 7 months gestation. Seventeen were found to have serum antibody to bovine viral diarrhea virus (BVDV), with highest titers to BVDV type 1. The fetus that was aborted at 5.5 months gestation, 3 months after the clinical outbreak, was found to be positive for BVDV on immunohistochemical staining, and noncytopathic BVDV type 1b was isolated. Of the 13 cria born alive that season, a single male underweight alpaca cria, born 9 months after the clinical illnesses, was infected with BVDV type 1b. The cria was positive for BVDV at birth, at 3 and 26 days of age and continued to be positive for noncytopathic BVDV using virus isolation, nested reverse transcription PCR, antigen detection ELISA, and immunohistochemical staining until euthanasia at 46 days of age. The cria remained serum antibody negative to both BVDV type 1 and type 2. A diagnosis of persistent infection was made. This is the first report describing persistent infection with BVDV in an alpaca cria.

Two llamas with pulmonary tumors were examined. Llama No. 1 had multiple nodules throughout the lung that consisted histologically of solid clusters of polygonal to spindle cells with rare glandular differentiation. Intravascular emboli were common. Similar neoplastic masses were present in the kidney, heart, and liver. Immunohistochemically, neoplastic cells were positive for broad-spectrum cytokeratins (CKs), high- molecular weight CKs, CKs 5/6, and vimentin. The diagnosis was pulmonary carcinoma. Llama No. 2 had pulmonary nodules without extrapulmonary involvement. Microscopically, neoplastic cells formed acini lined by simple epithelium and solid cords of squamous cells that sometimes surrounded acini. Neoplastic cells were strongly positive for broad-spectrum CKs and weakly positive for thyroid transcription factor-1. The diagnosis was adenosquamous carcinoma. Pulmonary tumors account for 23% of neoplasms in South American camelids in our laboratory, making this the second most common type of neoplasm after lymphosarcoma.

Malignant neoplasia in 4 alpacas was characterized by acute onset of clinical signs and rapidly deteriorating condition. Postmortem examination revealed metastatic or multicentric neoplasia in the abdominal organs of alpacas 1, 3, and 4 and an extensive thoracic mass in alpaca 2. Immunohistochemical stains supported a diagnosis of B-cell lymphosarcoma in alpacas 1–3 and a neuroendocrine neoplasm in alpaca 4.

A 9-month-old male llama ( Lama glama) was presented because of a rapidly growing mass on the right side of the face. Radiographs revealed a marked expansion of the right caudal face region with bone lysis involving the maxilla and the nasal, lacrimal, zygomatic, and palatine bones. Cytologically, the mass consisted of atypical round to polygonal cells with round nuclei and basophilic cytoplasms that formed acini and rows. Histologically, the mass consisted of anastomosing cords and sheets of neoplastic odontogenic epithelial cells embedded in a loose fibrovascular connective tissue. Single layers of peripheral, polarized, palisading, columnar epithelial cells were seen at the edges of some cords. Within the centers of the cords, epithelial cells showed rapid progression to keratin production. The histologic diagnosis was keratinizing ameloblastoma. Ameloblastomas are neoplasms of odontogenic epithelium that tend to be locally aggressive and can cause substantial destruction of bony structures. Because ameloblastomas do not tend to metastasize, they can be successfully treated by complete surgical excision, performed before extensive bony destruction occurs. Ameloblastoma, although expected to be rare, should be on the list of differential diagnoses for facial swelling in llamas.

Five camelid mucocutaneous fibropapillomas with histologic features similar to equine sarcoids were diagnosed. They were characterized by a dermal fibroblastic proliferation and overlying, often ulcerated hyperplastic epidermis with thin rete pegs extending down into the dermis. Two of the tumors came from llamas and three from alpacas. Four of the animals were 6-year-old females. The fifth was a 6-year-old castrated male. The fibropapillomas were located on the nose, lip, and cheeks. One of the llama tumors waxed and waned before surgery and recurred and spread after surgery. None of the other tumors recurred. All five tumors were positive for papillomavirus (PV) DNA by polymerase chain reaction testing. Nucleotide sequence analysis of the PCR product from one of the llama fibropapillomas confirmed a unique PV. This report provides the microscopic and clinical features of fibropapillomas in camelids as well as evidence for a PV etiology.

In October 2008, a 15-year-old female alpaca ( Vicugna pacos) housed at a breeding farm in northern California died after a brief illness characterized by sudden onset of weakness, recumbency, and respiratory distress. Postmortem examination revealed severe hydrothorax and hydropericardium, marked pulmonary edema, and acute superficial myocardial hemorrhage affecting the left ventricle. Bluetongue virus (BTV) was detected in the spleen by quantitative real-time reverse transcription polymerase chain reaction and confirmed by sequence analysis. No antibodies against BTV were detected in the serum using a competitive enzyme-linked immunosorbent assay, confirming acute, fulminant BTV infection.

A 4.5-year-old llama was admitted for evaluation of a firm mass rostral and ventral to the medial canthus of the left eye. Mucopurulent nasal discharge and absence of airflow through the left nostril were noted. Radiographs of the skull revealed a sharply demarcated soft tissue mass with faint mineralization. Endoscopy of the nasal passages revealed a mucosa-covered mass originating in the area of the second premolar, extending to the edge of the soft palate, and obstructing the airway. Examination of the oral cavity revealed a missing second molar and a mass protruding 2-cm from the empty alveolus. An ossifying fibroma, a previously unre-ported tumor in llamas, was diagnosed at postmortem examination.

An investigation was conducted for Mycobacterium avium ss paratuberculosis infections in a research herd of llamas and alpacas. Herd culture-negative status was established over a 23-month period by screening any individuals with any signs compatible with paratuberculosis ( n = 1), high serology values ( n = 8), or other health and research related reasons ( n = 24). There were no M. avium ss paratuberculosis isolates from radiometric cultures of multiple tissue and fecal samples from these individuals and no known sources of exposure. Paratuberculosis is uncommon in North American llamas and alpacas: only 5 cases were identified after an extensive search of the Veterinary Medical Data Base, diagnostic laboratory records, publication databases, and personal communications. Therefore, serum samples from llamas ( n = 84) and alpacas ( n = 16) in the culture-negative herd were used to obtain preliminary estimates of test specificity for 3 enzyme-linked immunoassays (ELISAs) and an agar gel immunodiffusion (AGID) assay kit for detecting serum antibodies to M. avium ss paratuberculosis in South American camelids. The ELISAs were modifications of established bovine assays for antibody detection. With provisional cutoffs, ELISA-A had 52 false positives (specificity 48%), ELISA-B had 8 false positives (specificity 92%), ELISA-C had two false positives (specificity 98%), and the AGID had 0 false positives (specificity 100%). The range of ELISA values for culture-positive llamas and alpacas ( n = 10) from other herds overlapped the range of values for culture-negative llamas and alpacas. The accuracy of the ELISAs may be improved by using age- and sex-specific cutoffs because uninfected male llamas and alpacas that were older than 1 year had higher values for some tests. These tests can be used for either llamas or alpacas; the protein-G conjugate ELISA (ELISA-B) may be useful for multispecies applications. These assays are best used for rapid presumptive diagnoses of llamas and alpacas with diarrhea and weight loss and as a screening tool for herds known to be exposed to infection. All seropositive results should be confirmed with culture.

A 6-year-old, female llama ( Lama glama) presented with progressive anorexia and ascites. Postmortem examination revealed an infiltrative uterine adenocarcinoma with widespread metastases. The neoplasm completely replaced and infiltrated the myometrium of the uterine body and cervix and metastasized largely to the serosal surfaces of the peritoneal cavity. Histopathology identified a highly invasive growth of neoplastic cells in solid packets or tubular arrangements and marked fibroplasia. No bovine or llama papillomavirus DNA was detected intralesionally by polymerase chain reaction.

A case of poisoning with a Cotoneaster sp. is described in a llama ( Lama glama). The clinical signs were dyspnea, with congested mucous membranes, chewing, recumbency, and opisthotonos. Several hours after ingestion of the plant, the llama died, despite treatment with sodium thiosulfate and nitrite. Necropsy revealed approximately 676 g of leaves and fruit of Cotoneaster in the first compartment of the stomach. The blood was light red and did not clot. Because Cotoneaster sp. contains low concentrations of cyanogenic glycosides, toxicosis occurs only following massive ingestion of plant material.

A 10-year-old, female, pregnant alpaca ( Vicugna pacos) presented with a discolored, swollen right eye. The eye did not respond to treatment and was enucleated. Sectioning of the fixed eye revealed an ocular mass replacing the aqueous and vitreous humors, with multiple regions of bone formation. Histopathological, immunohistochemical, and transmission electron microscopy confirmed the tumor was an intraocular melanoma with bone formation. Osteogenic melanoma is a rare variant of melanoma not reported in the eye before.

Prevalence and type of neoplastic disease were determined in 551 camelid submissions (368 alpacas [Lama pacos], 180 llamas [Lama glama], and 3 cases in which species was not identified) over a 5-year period. Forty neoplasms were identified in 38 animals (6.9%). Prevalence of neoplasia in llamas was higher (11%) than in alpacas (4.9%). Mean age of camelids with neoplasia was 9.42 ± 4.9 years. Mean age of alpacas with neoplasia (5.48 ± 3.7 years) was significantly less than of llamas with neoplasia (12.53 ± 3.2 years; P < 0.001). Cutaneous and mucocutaneous fibroma/fibropapilloma was most common (10 animals), followed by cutaneous and mucocutaneous squamous cell carcinoma (6 animals), disseminated lymphoma (5 animals), and fibrosarcoma (4 animals). Four of 5 animals with lymphoma were alpacas, aged 0.21 to 4 years. Lymphoma occurred in 1 aged llama (15 years). Disseminated carcinoma and adenocarcinoma occurred in 4 llamas and 2 alpacas, and included biliary (2), gastrointestinal (2), mammary gland (1), and unknown (1) origin. Mean age of camelids with any type of carcinoma or adenocarcinoma (12.36 ± 2.8 years) was significantly greater than that of camelids with lymphoma (4.24 ± 6.2 years; P = 0.02). Results indicate that neoplasia is relatively common in camelids and that there are differences between llamas and alpacas as regards prevalence of neoplasia, tumor types, and age at diagnosis.

Fifty clinically healthy llamas, 0.5–13 years of age (22 intact males, 10 neutered males, 18 females), with no biochemical evidence of liver disease or hematologic abnormalities, were selected to establish serum bile acid reference intervals. Serum samples submitted to the clinical pathology laboratory were analyzed using a colorimetric enzymatic assay to establish bile acid reference intervals. A nonparametric distribution of llama bile acid concentrations was 1–23 μmol/liter for llamas >1 year of age and 10–44 μmol/liter for llamas ≤1 year of age. A significant difference was found between these 2 age groups. No correlation was detected between gender and bile acid concentrations. The reference intervals were 1.1–22.9 μmol/liter for llamas >1 year of age and 1.8–49.8 μmol/liter for llamas ≤1 year of age. Additionally, a separate group of 10 healthy adult llamas (5 males, 5 females, 5–11 years of age) without biochemical or hematologic abnormalities was selected to assess the effects of feeding and time intervals on serum bile acid concentrations. These 10 llamas were provided fresh water and hay ad libitum, and serum samples were obtained via an indwelling jugular catheter hourly for 11 hours. Llamas were then kept from food overnight (12 hours), and subsequent samples were taken prior to feeding (fasting baseline time, 23 hours after trial initiation) and postprandially at 0.5, 1, 2, 4, and 8 hours. In feeding trials, there was no consistent interaction between bile acid concentrations and time, feeding, or 12-hour fasting. Prior feeding or time of day did not result in serum bile acid concentrations outside the reference interval, but concentrations from individual llamas varied within this interval over time.

Asa SL: 1993, The endocrine pancreas and its tumors. Endocr Pathol 4:120-130. Feldman EC, Nelson RW: 1987, Gastrointestinal endocrinology. In: Canine and feline endocrinology and reproduction, ed. Pedersen D, pp. 375-398. WB Saunders, Philadelphia, PA. Happe RP, van der Gaag I, Lamers CBHW, et al.: 1980, Zollinger-Ellison syndrome in three dogs. Vet Pathol 17:177-186. Hawkins KL, Summers BA, Kuhajda FP, Smith CA: 1987, 5.

Immunoglobin G (IgG) quantitation was performed by a commercially available single radial immunodiffusion kit on 528 plasma samples obtained from llamas. Fifty samples encompassing the range of values obtained were selected for further evaluation. The IgG concentration of these samples was measured by a second commercially available single radial immunodiffusion kit and a sodium sulfite precipitation kit. γ-Globulins also were measured. IgG values predicted by the single radial immunodiffusion kits were not in agreement. Failure to appreciate this lack of agreement could result in misinterpretation of a llama's IgG level derived from one kit when clinical guidelines established using the other kit are followed.

A frozen, stillborn alpaca ( Lama pacos) was submitted to the Minnesota Veterinary Diagnostic Laboratory for diagnostic purposes. No gross or histopathologic changes of any significance were seen. A pool of lung, liver, and brain tissues was positive for bovine viral diarrhea virus (BVDV) by reverse transcription–polymerase chain reaction. On inoculation in cell cultures, a noncytopathic BVDV (type 1b) was isolated. No evidence of BVDV was seen on immunohistochemical examination of tissues. This indicates the importance of using multiple tests for arriving at a diagnosis and appears to be the first report of BVDV isolation from alpaca.

>> the meningoencephalitic form of the disease. 2,11 Listeria1 abortion is relatively common in sheep, cattle, and goats, is rare in other species, 1 and has not been reported previously in llamas. In sheep and cattle, there is often clinical illness with fever of up to 40.5 C in the dam, but meningoencephalitis does not usually occur concomitantly with abortion. Abortion usually occurs during the latter stages of gestation, as in this case. Ingestion is considered the most common route of infection leading to abortion. 3 Listeria monocytogenes is ubiquitous in nature and in human and animal feces, so llamas will almost certainly be exposed to the organism. Infection has been repeatedly associated with spoiled silage with a pH >5.0-5.5 1,3 and with various circumstances that might lower the animal’s resistance, including pregnancy. 3 Eperythrozoonosis has also been associated with conditions causing immune suppression 5,9

A virus known to cause multiple problems in cattle, bovine viral diarrhea virus, was isolated from 3 different cases in New World camelids. Virus isolation, immunoperoxidase staining, and fluourescent antibody staining were used to detect the virus. The herds involved were screened for antibody titers to bovine viral diarrhea and virus isolation from the buffy coat. Bovine viral diarrhea virus should be considered as a cause of death in young and old New World camelids.

Foot-and-mouth disease virus (FMDV) was shown to be transmitted from either cattle to llamas, llamas to swine (interspecies), or llamas to llamas (intraspecies). Response to FMDV varied greatly in the 6 llamas studied; 3 llamas developed generalized clinical disease with mild pyrexia, 2 after intradermolingual inoculation, and 1 after exposure to a calf infected with FMDV serotype A24. Another contact llama developed vesicular lesions on all 4 extremities but no oral lesions. Two contact llamas, in separate study groups, did not seroconvert or develop clinical signs of FMDV infection. All 4 llamas showing clinical disease developed virus- neutralizing antibodies against FMDV A24 and antibodies against the virus-infection-associated antigen. Virus- neutralizing antibody titers remained elevated for over 200 days postinoculation or exposure. Antibodies to virus-infection-associated antigen were detected several days after virus-neutralizing antibody appeared and became weaker 100-125 days post-FMDV exposure in 3 of the 4 clinically affected llamas. One inoculated llama was still positive for virus-infection-associated antigen at 360 days after inoculation. Foot-and-mouth disease virus A24 was not detected from esophageal-pharyngeal fluid specimens beyond 8 days postexposure using in vitro techniques. Four native species of camelids are found in the Americas: the llama (Lama gama), the alpaca (L. pa- cos), the guanaco (L. guanacoe), and the vicuna (L. vicugna). The South American camelids are indigenous to the Andean mountain peaks and high plains and prairies of Peru, Bolivia, Ecuador, Argentina, and Chile 26 Since 1978 Chile has kept foot-and-mouth disease (FMD) from becoming reestablished as an en- zootic disease by extensive border surveillance and vigorous control measures. 3,6,7 However, efforts by Chile to be recognized as free of FMD by national and in- ternational governing bodies have been twice thwarted by outbreaks of the disease in 1984 and in 1987. 1,3,7,20- 25 On both occasions, alleged contraband movement of infected cattle into Chile was responsible for the outbreaks. 3,7 In neither of these FMD outbreaks were camelids known to be clinically affected. Epidemiological studies of FMD in Old World camelids, Camelus dromedarius and C. bactrianus, members of the same family as the llama, have been conducted in the Middle East. In one of these studies, foot-and-mouth disease virus (FMDV) was isolated from esophageal-pharyngeal (OP) samples through 5 weeks postinoculation, and seroconversion was doc

Over the past decade there has been an increased number of llamas and alpacas raised in North America, with a heavy concentration in the Northwest. This increase serves as an impetus for studying the comparative features of the South American camelids in relation to our domestic animal species. The llama and the alpaca occupy a unique epidemiological position between members of the equine and bovine species in terms of their susceptibility to infectious agents that are known to infect either horses and/or cattle. 9,10,12,13 This report describes the isolation of a virus with in vitro properties of bovine herpesvirus type 1 (BHV-1), infectious bovine rhinotracheitis (IBR), from the lungs of a llama with bronchopneumonia. The subject was a 3-year-old female llama in the later stages of pregnancy that had a 2-month history of a productive cough and gradual weight reduction. The vaccination history indicated the use of an 8-way clostridial bacterin but no use of viral vaccines. The llama was presented live to the clinic and was anorexic and recumbent. A tracheal wash was performed for bacterial and viral culture and a blood sample obtained for serology. Within 1 day of admittance to the clinic, the llama died. A postmortem examination revealed gross lesions confined to the pleural cavity. The lungs appeared congested and hemorrhagic with small bronchi filled with clotted blood and a bloody froth within the trachea and esophagus. Samples collected at necropsy for laboratory diagnostic procedures included fluid from the pericardial sac and fresh and fixed portions of the lungs, heart, and kidney. Formalin-fixed sections of lung, kidney, and heart were stained with hematoxylin and eosin for routine evaluation. The Brown and Brenn stain was used to evaluate selected sections for the presence of bacteria. Histology of the tissues revealed lesions confined to the lung. A few randomly scattered alveoli contained low numbers of degenerating neutrophils and foamy macrophages. Some of the adjacent bronchioles also contained clumps of degenerating neutrophils and cell debris. Moderate diffuse congestion was present. No inclusion bodies or bacteria were noted in the sections observed. The histologic changes in the lung were regarded as mild and acute and did not explain the death of the llama. The pulmonary changes were reflective of an early inflammatory response compatible with a bacterial infection. The morphologic diagnosis was an acute, mild, multifocal neutrophilic bronchopneumonia consistent with an early inflammatory response to a bacterial infection. The samples collected antemortem and at postmortem were