Diseases (Bacterial)

  • A Proof of Concept Study to Assess the Potential of PCR Testing to Detect Natural Mycobacterium bovis Infection in South American Camelids

    Cases of Mycobacterium bovis infection South American camelids have been increasing in Great Britain. Current antemortem immunological tests have some limitations. Cases at post mortem examination frequently show extensive pathology. The feasibility of detecting Mycobacterium bovis DNA in clinical samples was investigated.More »
  • Culture-Positive Sepsis in Neonatal Camelids: 21 Cases

    Crias with sepsis do not appear to present with major biochemical, hematologic, or blood gas abnormalities, potentially complicating diagnosis. Affected crias may not have localizing signs at presentation and are not usually febrile, although hypothermia, tachypnea, and tachycardia are relatively common. Total protein concentration was not a substitute for immunoglobulin G measurement in septic crias in this study. Familiarity with the clinical presentation and common pathogens isolated should improve early recognition and treatment and ultimately outcome of crias with sepsis.More »
  • Eperythrozoon or Mycoplasma haemolamae: New Name for an Old Problem

    Recently, the red blood cell parasite Eperythrozoon (commonly know as “Epe”) was renamed Mycoplasma haemolamae based on the results of genetic studies done on the organism. This change in name is just that, a name change; it does not reflect any change in our understanding of the biology of this organism and the disease it causes. If you have had to deal with Epe in your alpacas, you know that we in the veterinary profession still have a great deal to learn about this organism, but this article will summarize what we currently do understand.More »
  • Infection with Corynebacterium pseudotuberculosis in Five Alpacas

    Among the population of an alpaca breeding farm, 5 alpacas (22 days to 14 months old) developed focal swellings in the subcutaneous tissues of the head or neck. Infection with Corynebacterium pseudotuberculosis was confirmed on the basis of results of microbial culture of abscess material and a serum hemolysis inhibition assay to detect C. pseudotuberculosis toxin. The dams of the affected alpacas were seronegative for C. pseudotuberculosis toxin. The affected alpacas underwent surgical excision of the abscesses and were isolated from herdmates for 90 days; treatment was successful, and no other alpacas in the herd became infected. Common risk factors for sources of infection in the affected alpacas included housing in a maternity barn and a pasture. Also, the infection potentially originated from new alpacas introduced into the herd during the preceding 3 months. Infection with C. pseudotuberculosis should be considered as a differential diagnosis for camelids with peripheral lymphadenopathy or abscesses in subcutaneous tissues.More »
  • Investigator Profile: Susan Tornquist, DVM, MS, PhD, Dip. ACVP

    An Eperythrozoon is a little bacterium that affects the red blood cells. It actually sits on the red blood cells and the immune system sees that as a problem and figures it has to take out the red blood cells and destroy them. It can lead to severe anemia or mild or moderate anemia, particularly in animals that are stressed or immune-compromised. I don't want to give the impression that this disease is killing alpacas right and left. The organism probably does not kill animals — at least by itself. We see it more often as a complicating factor in other diseases, and in that sense, it's worth figuring out more about it and how to prevent it.”More »
  • Mycoplasma haemolamae in Alpacas with Ill-thrift and Anaemia

    In July 2018, four alpacas on a property north-east of Melbourne presented with ill-thrift and anaemia. Samples sent for laboratory testing confirmed infection with Mycoplasma haemolamae (previously Eperythrozoon sp.).More »
  • Prevalence of Mycobacterium avium subsp. paratuberculosis Fecal Shedding in Alpacas Presented to Veterinary Hospitals in the United States

    Background The prevalence of Johne's disease in alpacas in the United States is unknown. The limits of polymerase chain reaction (PCR) detection of Mycobacterium avium subsp. paratuberculosis (MAP) in alpaca feces have not been determined. Objectives To evaluate the use of PCR for MAP detection in alpaca feces; and to estimate the prevalence of MAP fecal shedding in alpacas presented to veterinary teaching hospitals. Animals Alpacas presenting to 4 US veterinary teaching hospitals from November 2009 to February 2011. Methods Prospective study. Ten dilutions of a wild MAP strain were added to negative alpaca feces and processed for MAP detection by means of a commercial real‐time PCR (RT‐PCR) assay, and cultured on Herrold's Egg Yolk Medium (HEYM) and liquid broth. The limits of detection for each method were determined. Fecal samples from alpacas admitted to the veterinary teaching hospitals during the study period were evaluated for MAP via PCR and HEYM. Results The lowest MAP dilution detectable via PCR was 243 MAP colony‐forming units (CFU)/g of feces, at which concentration MAP growth was detectable on HEYM. Ten (6%; 95% confidence interval: 3–9%) of the 180 fecal samples collected were positive on PCR. Conclusions and Clinical Importance Polymerase chain reaction can provide an accurate and rapid detection of MAP fecal shedding in alpacas; and the prevalence of MAP fecal shedding in hospitalized alpacas in 4 US veterinary teaching hospitals was 6%.More »
  • Tuberculosis in Alpaca (Lama pacos) on a Farm in Ireland. 1. A Clinical Report

    This case report describes tuberculosis (TB) due to infection with Mycobacterium bovis (M. bovis) in alpaca (Lama pacos) on a farm in Ireland. Two severely debilitated alpaca were presented to the University Veterinary Hospital, University College Dublin in November 2004. Bloods were taken, and haematology and biochemistry results were indicative of chronic infection. Radiological examination showed evidence of diffuse granulomatous pneumonia suggestive of tuberculosis. On necropsy there were granulomatous lesions present throughout many body organs including lung, liver, kidney, intestine as well on peritoneum and mesentery. Culture of acid-fast bacilli from lesions led to a diagnosis of tuberculosis due to M. bovis. The use of intradermal skin testing proved inefficient and unreliable for ante mortem diagnosis of tuberculosis in alpaca. Infection due to M. bovis should be considered among the differential diagnoses of debilitating diseases in alpaca, particularly those farmed in areas known to be traditional black spots for tuberculosis in cattle.More »
  • Tuberculosis in Alpaca (Lama pacos) on a Farm in Ireland. 2. Results of an Epidemiological Investigation

    Tuberculosis (TB), due to infection with Mycobacterium bovis was diagnosed in a flock of alpaca in Ireland in 2004. An epidemiological investigation was conducted to identify the risk of TB for farmed alpaca where TB is endemic, the origin of the infection, the potential for alpaca-to-alpaca transmission and appropriate control measures. The investigation focused on the alpaca flock (including the farm, animal movements and breeding, feeding and flock health practice), the disease episode (including animal disease events and subsequent control measures) and TB infection risk in the locality. The TB risk to alpaca is high in areas where infection is endemic in cattle and badgers and where biosecurity is inadequate. It is most likely that the source of infection for the alpaca was a local strain of M. bovis, present in cattle in this area since at least 2001. Genotyping of isolates identified a single variable number tandem repeat (VNTR) profile in both cattle and alpaca in this region. Although a tuberculous badger was also removed from the vicinity, bacterial isolation was not attempted. On this farm, infection in alpaca was probably derived from a common source. Alpaca-to-alpaca transmission seems unlikely. Two broad control strategies were implemented, aimed at the rapid removal of infected (and potentially infectious) animals and the implementation of measures to limit transmission. Tests that proved useful in detecting potentially-infected animals included measurement of the albumin-to-globulin ratio and regular body condition scoring. Skin testing was time consuming and unproductive, and early detection of infected animals remains a challenge. The flock was managed as a series of separate groupings, based on perceived infection risk. No further TB cases have been detected.More »
  • Use of a Polymerase Chain Reaction Assay to Study Response to Oxytetracycline Treatment in Experimental Candidatus Mycoplasma haemolamae Infection in Alpacas

    Objective—To develop a PCR assay for Candidatus Mycoplasma haemolamae (CMhl) infection in alpacas and use it to study the efficacy of oxytetracycline treatment and development of a subclinical carrier state. Animals—8 healthy adult alpacas. Procedures—Alpacas initially had negative results for CMhl in blood samples via PCR assay and were experimentally infected with CMhl; 4 were treated with oxytetracycline, and 4 were not treated. All were monitored regularly via PCR assay, blood smear examination, PCV, rectal temperature, and physical examination. At 6 months after treatment, all alpacas were immunosuppressed by administration of dexamethasone and tested for CMhl. Results—7 of 8 alpacas had positive PCR assay results 4 to 6 days after experimental infection. When organisms were detectable on a blood smear, they were seen 2 to 6 days after positive results of PCR assay. Infection was often associated with mild anemia that was usually transient. No alpacas became hypoglycemic. Oxytetracycline treatment was not associated with faster clearance of organisms or resolution of anemia, and 4 of 4 treated alpacas still had positive results of PCR assay when immunosuppressed 6 months later; 0 of 3 nontreated alpacas had positive results of PCR assay following immunosuppression. Transient fever was detected in 3 alpacas during immunosuppression. Conclusions and Clinical Relevance—The PCR assay was more sensitive than blood smear examination for detection of infection. Clinical signs, anemia, and fever were not necessarily associated with infection. Oxytetracyline administration did not consistently clear CMhl infection. Although treated with oxytetracycline, infected alpacas remained chronic carriers.More »