Author:

Keywords:

histomonas meleagridis, internal amplification controls, diagnostic pcr, blackhead disease, diagnosis, model, Science & Technology, Life Sciences & Biomedicine, Parasitology, Veterinary Sciences, Histomonas meleagridis, diagnostic PCR, BLACKHEAD DISEASE, DIAGNOSIS, MODEL, Animals, Base Sequence, DNA Primers, DNA, Protozoan, Eukaryota, False Negative Reactions, Gene Amplification, Polymerase Chain Reaction, Poultry Diseases, Protozoan Infections, Animal, Sensitivity and Specificity, Turkeys, 0605 Microbiology, 0704 Fisheries Sciences, 0707 Veterinary Sciences, Mycology & Parasitology, 3009 Veterinary sciences

Abstract:

Histomoniasis or blackhead is a disease of gallinaceous birds, caused by the protozoon Histomonas meleagridis. Since traditional diagnostics for the detection of this disease are complex and far less sensitive than molecular tools, a PCR would provide a more rapid and sensitive alternative. However, intestinal material and droppings, which are preferably used in epidemiological studies of histomoniasis, often contain PCR inhibitory substances. To detect these false negative results, the use of an internal amplification control is essential. Nevertheless, the recently developed PCR tests lack this internal control. Therefore, a new PCR assay with H. meleagridis specific primers was developed which does include an internal amplification control. The diagnostic value of the PCR assay was evaluated in comparison to three other conventional H. meleagridis specific PCR tests (HIS5, HM1 and HM2). None of the organ samples originating from uninfected turkeys, showed positive PCR results in any of the tests. Among the lesion-positive, inhibition-free samples, 95.4% were positive by our PCR assay, while only 50, 66.7 and 83.3% of the lesion-positive organs tested positive by the HM1, the HIS5 and the HM2 PCR respectively. In conclusion, our PCR offers the use of the internal control to detect false negative results and an increased sensitivity, and thus should be useful for routine diagnosis of H. meleagridis in poultry. (c) 2006 Elsevier B.V All rights reserved.