Molecular Detection of Toxoplasma gondii Using Real-Time PCR in Broiler Chickens from Baghdad City, Iraq

Document Type : Research Paper

Author

Department Microbiology, College of Veterinary Medicine, University of Baghdad, Baghdad, Iraq

Abstract

Objective
Toxoplasma gondii is an intracellular protozoan parasite responsible for toxoplasmosis, an important zoonotic disease affecting humans and animals worldwide. Broiler chickens are considered potential sources of infection due to their exposure to contaminated environments and their role in food transmission. The present study aimed to detect T. gondii in broiler chickens in Baghdad city using conventional PCR and reverse transcription quantitative PCR (RT-qPCR) techniques.
Materials and methods
A total of 50 broiler chicken samples were collected from local live chicken selling and slaughtering markets in different areas of Baghdad city, including Abu Ghraib, Al-Ghazaliya, Al-Adl, Al-Shorja, and Jameela markets, during the period from January 2026 to June 2026. Blood samples were collected under aseptic conditions and transferred to the College of Veterinary Medicine, University of Baghdad, for molecular examination. Genomic DNA was extracted for conventional PCR analysis, while total RNA was extracted, reverse-transcribed into cDNA, and analyzed by RT-qPCR targeting the B1 gene of T. gondii.
Results
Conventional PCR successfully amplified the 18S rRNA gene, producing the expected 976 bp amplicon confirmed by agarose gel electrophoresis. T. gondii was identified in 20 of 50 (40.0%) blood samples from broiler chickens, whereas 30 (60.0%) were negative for T. gondii by RT-qPCR targeting of B1 gene. Ct values ranged from 27.5 to 41.9 in the positive samples. The difference between positive and negative samples (P = 0.0471, P ≤ 0.05) was proved by statistical analysis of the data.
Conclusion
The study concluded that broiler chickens in Baghdad city may play an important role in the transmission of toxoplasmosis and represent a potential public health risk. Real-Time PCR was found to be a sensitive and reliable method for molecular detection of T. gondii infection in broiler chickens.


Keywords

References

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Agricultural Biotechnology Journal
Volume 18, Issue 4
August 2026
Pages 649-662

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