Seroprevalence of bovine viral diarrhea virus in alpacas in the United States and assessment of risk factors for exposure, 2006-2007.

OBJECTIVE: To estimate seroprevalence of antibodies against bovine viral diarrhea virus (BVDV) and incidence of seroconversion in alpacas in the United States during 2006 to 2007 and to evaluate associations between BVDV seropositive status and potential risk factors for exposure to BVDV. DESIGN: Cross-sectional and longitudinal cohort study. SAMPLE: Blood samples from 192 alpacas > 6 months old in 39 herds from 20 states; 40 owners who completed questionnaires. PROCEDURES: 550 US alpaca owners, stratified by state and randomly selected from a list of approximately 4,300 owners, were mailed a study description, voluntary participation request, and questionnaire. Thirty-nine owners submitted blood samples from up to 6 alpacas > 6 months old; 27 of 39 owners submitted another blood sample from the same alpacas > 1 month later. Samples were tested for serum virus-neutralizing antibodies against BVDV. Seropositive status was used to indicate BVDV exposure. Associations between seropositive status and potential risk factors for BVDV exposure described in questionnaires were evaluated by use of a Fisher exact test. RESULTS: 8 of 192 (4.2%) alpacas in 3 of 39 (7.7%) herds were seropositive. Larger herds had a greater percentage of seropositive alpacas than did smaller herds. No alpaca from which a second blood sample was obtained seroconverted during 292 to 1,460 alpaca-days (mean, 740 alpaca-days) of potential exposure. CONCLUSIONS AND CLINICAL RELEVANCE: Results contributed to information on assessment of BVDV prevalence, risk factors for exposure, and alpaca industry practices in 2006 to 2007 during the emergence of BVDV as a major disease in alpacas.

Identification of Lamanema chavezi Becklund 1963 infection in a llama (Lama glama) in the United States.

Infection with Lamanema chavezi, a parasitic nematode of New World camelids, was diagnosed by examination of feces and formalin-fixed liver from a 14-month-old female llama (Lama glama) that died after a 6-week illness. Infection with L. chavezi was initially suspected when a granuloma containing an unidentified nematode was detected microscopically in the hepatic parenchyma from a necropsy specimen. The subsequent diagnosis of L. chavezi infection was based on the morphologic features of 2 immature nematodes dissected from individual hepatic granulomas, characteristics of eggs detected in feces of the llama by centrifugal flotation in sugar solution (specific gravity: 1.30), development of third-stage larvae within the eggs after incubation of the llama feces at room temperature for ≥30 days, and the morphology of third-stage larvae released from the embryonated eggs. Collectively, these findings indicate that the llama, born and raised in Oregon, harbored an autochthonous L. chavezi infection. Eggs identified as L. chavezi were also detected by centrifugal flotation of pelleted feces from 3 of 7 herd mates of the llama indicating this parasite is endemic in the Oregon herd. The findings reported herein serve to alert diagnosticians and veterinary practitioners to the occurrence of L. chavezi in New World camelids in the United States and describe diagnostic features of this potential pathogen.