Bovine tuberculosis (TB) is endemic in Kuwait; cattle identified as TB-positive using the caudal fold test (CFT) are culled. We used a Bayesian approach to estimate the sensitivity (Se) and specificity (Sp) of the IFNγ assay and ELISA, which are not routinely used in Kuwait in CFT-negative dairy cattle. Blood samples from CFT-negative cattle (n = 384) collected from 38 dairy farms were tested by IFNγ assay and ELISA. The Se and Sp (95% CI) of the IFNγ were 85.0% (67.6–95.3%) and 90.4% (86.7–95.3%), respectively, whereas estimates for the ELISA were 61.1% (33.1–84.6%) and 85.4% (81.7–88.8%). TB prevalence (95 CI%) in CFT-negative cattle was estimated as 2.6% (0.5–9.5%). The IFNγ assay may play a role as an ancillary test for the identification of Mycobacterium bovis–infected cattle that are undetected by CFT.
Bibliographical noteFunding Information:
The support provided by the management and other departments of the Kuwait Institute for Scientific Research is gratefully acknowledged. We thank the Public Authority for Agriculture Affairs and Fish Resources (PAAFR) and the Kuwait Union of Dairy Producers for technical cooperation provided during the study, and Dr. Y Al-Azemi for technical assistance. We are grateful to OMICS RU project SRUL02/13 in the RCF Research Core Facility at Kuwait University for the use of unit facilities.
Research was funded by the Kuwait Foundation for the Advancement of Sciences (KFAS).
- Bovine tuberculosis
- gamma interferon