Identification of <i>Trichinella</i> species among wild carnivores in north, northeast, and northwest provinces of Iran.

<i>Trichinella britovi</i> is a species circulating in Iran and has already been observed in wild and domestic carnivores. The present study aims to determine the occurrence of <i>Trichinella</i> species in Iran's most important provinces, including the northern, northeastern, and northwest regions. In total, 93 carcasses of golden jackals, collected due to road accidents between 2019 and 2022, have been obtained from Ardabil, Mazandaran, Golestan, North Khorasan, and Khorasan Razavi provinces, Iran. Genomic DNA (four positives out of 93 carcasses) from each Trichinella genotype was amplified in a multiplex polymerase chain reaction (PCR) reaction. To confirm the multiplex PCR results, the sequences of the PCR products with cytochrome oxidase subunit I were sent to a reference laboratory within the European Union. Bioinformatics software was used to verify the sequencing results of primer fragments and to compare and analyze the results obtained with the sequences stored in the NCBI genetic database. Following multiplex PCR amplification, a two-band pattern was observed. <i>Trichinella britovi</i> larvae displayed the expected band pattern of 127 bp and 253 bp. The PCR products amplified using primers specific for the <i>cytochrome oxidase subunit I</i> gene showed 861 base pair bands in all four samples analyzed. The obtained sequences of cytochrome oxidase subunit I from all four individual muscle larvae had 100% identical haplotypes except for one nucleotide transversion in one sequence. As a result of this study, valuable insights into <i>T. britovi</i> prevalence and phylogenetic distribution among Iranian golden jackals have been gained in terms of prevalence and phylogenic distribution.