TB in llamas caused by <i>Mycobacterium bovis</i>

Twomey, D. F.; Crawshaw, T. R.; Anscombe, Jane; Farrant, L.; Evans, LC; McElligott, W. S.; Higgins, Robert; Dean, Gillian S.; Vordermeier, Martin; Jahans, Keith; Rúa-Doménech, Ricardo de la

doi:10.1136/vr.160.5.170

Cited by 30 publications

(40 citation statements)

References 2 publications

(2 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Until recently, the intradermal tuberculin test was the only test available for camelid species and it is still considered the official TB screening and pre-export certification test for SAC in many countries (37,44). However, the skin tests are difficult to standardize and can reportedly produce unacceptably high rates of false-positive and/or false-negative results (10,33,36,38,45). In two Swiss herds of SAC where 10 animals were diagnosed with generalized M. microti infection, the skin test detected no reactors (22).…”

Section: Discussionmentioning

confidence: 99%

“…M. bovis in particular is also known to cause TB in a broad range of domestic and wild mammal species (24,35). Infections with M. bovis have been shown to affect both New and Old World species of camelids (14,36,44,45). Tuberculosis in South American camelids (SAC), particularly in alpacas and llamas, has recently gained particular attention in Europe and in the United States, where these animals are being increasingly traded and kept in growing numbers as an alternative livestock industry (1).…”

mentioning

confidence: 99%

“…These infections are usually difficult to recognize in live animals because of the lack of reliable antemortem diagnostic tests and the nonspecific nature of the clinical signs of TB (4,12). The intradermal tuberculin test is used in many countries, but that method is cumbersome and has poor accuracy in SAC testing (10,33,36). Serological assays may constitute a promising alternative approach (7,22), but additional studies using sufficient numbers of well-characterized individuals from various SAC populations of known TB status are needed to validate the diagnostic performance of such diagnostic methods.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Diagnostic Value of Animal-Side Antibody Assays for Rapid Detection of Mycobacterium bovis or Mycobacterium microti Infection in South American Camelids

Lyashchenko

Greenwald

Esfandiari

et al. 2011

Clin Vaccine Immunol

View full text Add to dashboard Cite

Tuberculosis (TB) in South American camelids (SAC) is caused byMycobacterium bovis or Mycobacterium microti. Two serological methods, rapid testing (RT) and the dual-path platform (DPP) assay, were evaluated using naturally infected SAC. The study population included 156 alpacas and 175 llamas in Great Britain, Switzerland, and the United States. TB due to M. bovis (n ‫؍‬ 44) or M. microti (n ‫؍‬ 8) in 35 alpacas and 17 llamas was diagnosed by gross pathology examination and culture. Control animals were from herds with no TB history. The RT and the DPP assay showed sensitivities of 71% and 74%, respectively, for alpacas, while the sensitivity for llamas was 77% for both assays. The specificity of the DPP assay (98%) was higher than that of RT (94%) for llamas; the specificities of the two assays were identical (98%) for alpacas. When the two antibody tests were combined, the parallel-testing interpretation (applied when either assay produced a positive result) enhanced the sensitivities of antibody detection to 89% for alpacas and 88% for llamas but at the cost of lower specificities (97% and 93%, respectively), whereas the serial-testing interpretation (applied when both assays produced a positive result) maximized the specificity to 100% for both SAC species, although the sensitivities were 57% for alpacas and 65% for llamas. Over 95% of the animals with evidence of TB failed to produce skin test reactions, thus confirming concerns about the validity of this method for testing SAC. The findings suggest that serological assays may offer a more accurate and practical alternative for antemortem detection of camelid TB.Tuberculosis (TB) remains one of the most challenging and widespread zoonotic diseases in many countries (5,6,34). Mycobacterium tuberculosis and Mycobacterium bovis are the primary etiologic agents for human and bovine TB, respectively (8,30,39). M. bovis in particular is also known to cause TB in a broad range of domestic and wild mammal species (24,35). Infections with M. bovis have been shown to affect both New and Old World species of camelids (14,36,44,45). Tuberculosis in South American camelids (SAC), particularly in alpacas and llamas, has recently gained particular attention in Europe and in the United States, where these animals are being increasingly traded and kept in growing numbers as an alternative livestock industry (1). In recent years, M. bovis infections have been documented in alpaca and llama herds in parts of Europe, such as Great Britain (GB) (7, 37, 38), Ireland (32), and Spain (11), where this infection is endemic in cattle and wildlife. Also, SAC are known to be susceptible to M. microti, another member of the M. tuberculosis complex that can cause generalized disease with a fatal outcome in SAC (26,29,46). These infections are usually difficult to recognize in live animals because of the lack of reliable antemortem diagnostic tests and the nonspecific nature of the clinical signs of TB (4, 12). The intradermal tuberculin test is used in many countries, but that method is...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Diagnostic Value of Animal-Side Antibody Assays for Rapid Detection of Mycobacterium bovis or Mycobacterium microti Infection in South American Camelids

Lyashchenko

Greenwald

Esfandiari

et al. 2011

Clin Vaccine Immunol

View full text Add to dashboard Cite

show abstract

“…Camelids are known to be susceptible to MTC, including M. tuberculosis, M. bovis, and/or Mycobacterium microti (8,17,23), and to Mycobacterium kansasii infections (11). Furthermore, TB cases have been recently reported in alpacas and llamas from different European countries (2,14,16,20).…”

Section: Herdmentioning

confidence: 99%

“…The Bovigam test is a current method of diagnosis for cattle; however, it has already been reported to be a nonvalid test for the diagnosis of TB in camelids (22). The intradermal tuberculin test, which is the traditional diagnostic approach for a number of other species, is believed to produce nonspecific reactions in camelids (6,8,20). Serological assays may be a promising alternative, but little is known about antibody responses during TB in these species (14,23).…”

Section: Herdmentioning

confidence: 99%

Tuberculosis in Alpacas ( Lama pacos ) Caused by Mycobacterium bovis

et al. 2010

View full text Add to dashboard Cite

We report three cases of tuberculosis in alpacas from Spain caused by Mycobacterium bovis. The animals revealed two different lesional patterns. Mycobacterial culture and PCR assay yielded positive results for M. bovis. Molecular typing of the isolates identified spoligotype SB0295 and identical variable-number tandem repeat (VNTR) allele sizes. CASE REPORT Herd 1. The affected herd comprised 32 alpacas (26 adults and six juveniles) and was located in the Ronda region (southern Spain). The animals were raised in outdoor facilities and were fed with commercial pellet feed, hay, and water ad libitum. In March 2009, a 7-year-old female alpaca (alpaca 1) showed dyspnea, fever, depression, lethargy, anorexia, and weight loss. One month later, an 8-year-old male alpaca (alpaca 2) presented chronic weight loss, bruxism, and dyspnea.

show abstract

Comparative assessment of postmortem inspection and immunochromatographic techniques for the detection of bovine tuberculosis in slaughter cattle in Nigeria

Okoro

Anosa

Oboegbulem

et al. 2014

Trop Anim Health Prod

View full text Add to dashboard Cite

Animals with tuberculosis pose some risks to humans, especially in developing countries of the world. In this study, postmortem inspection (PMI) and immunochromatographic assay (ICA) techniques were compared for the detection of bovine tuberculosis (BTB) in slaughter cattle in Enugu State, Nigeria using culture as the gold standard. A cross-sectional study was conducted from January-June, 2011 on animals presented at four purposively selected slaughterhouses in the study area, involving a total of 500 randomly selected animals. Blood samples were collected from the jugular veins of selected animals and serum samples harvested for ICA. Thorough PMI was carried out and tissue samples from the lung, liver, intestine, and lymph nodes were collected, with or without lesions for culture; from the animals examined, culture detected 11 positive cases giving a prevalence rate of 2.2 %, whereas PMI detected 22 positive cases including 7 (out of the 11) positive cases detected by culture, giving a prevalence rate of 4.4 %. Fifteen of the cases detected as positive by PMI were negative by culture. Therefore, the sensitivity and specificity of PMI were 64 and 97 %, respectively. ICA detected 59 positive cases including 10 of the 11 positive cases detected by culture, hence, a prevalence rate of 11.8 %. Forty-nine of the cases detected as positive by ICA were negative by culture. Hence, the sensitivity and specificity of ICA were 91 and 90 %, respectively. In conclusion, the performance of ICA was found sufficiently high to support its use in BTB surveillance and control in cattle in Enugu State, Nigeria.

show abstract

TB in llamas caused by Mycobacterium bovis

Cited by 30 publications

References 2 publications

Diagnostic Value of Animal-Side Antibody Assays for Rapid Detection of Mycobacterium bovis or Mycobacterium microti Infection in South American Camelids

Diagnostic Value of Animal-Side Antibody Assays for Rapid Detection of Mycobacterium bovis or Mycobacterium microti Infection in South American Camelids

Tuberculosis in Alpacas ( Lama pacos ) Caused by Mycobacterium bovis

Comparative assessment of postmortem inspection and immunochromatographic techniques for the detection of bovine tuberculosis in slaughter cattle in Nigeria

Contact Info

Product

Resources

About