DHARVI CHHABRA, UMESH GOUTAM, ANJU MANUJA AND BALVINDER KUMAR*
Department of Equine Health Division and Animal Biotechnology, ICAR-National Research Centre on Equines, Hisar-125 001 (Haryana), India
*(e-mail: bmanuja.nrce@gmail.com; Mobile: 9466128008)
(Received: March 30, 2025; Accepted: May 10, 2025)
ABSTRACT
Strangles is a highly contagious bacterial infection affecting the upper respiratory tract of equids, caused by Streptococcus equi subsp. equi, a -hemolytic, gram-positive bacterium classified under Lancefield group C. Early and precise identification of the pathogen is crucial for effective disease control. This study focused on the molecular detection of Streptococcus equi M like Protein (SeM) gene, a surface protein from clinical cases of Strangles in Indian equines. A total of 45 isolates obtained from abscess material and nasal swabs of clinically diagnosed and apparently healthy Indian equines were analyzed. DNA was extracted and amplified using gene-specific primers targeting a 541 bp region of the SeM gene. PCR results confirmed the presence of the SeM gene in the isolates, demonstrating the effectiveness of this molecular approach for the detection and identification of S. equi and serving as a highly specific molecular marker. PCR was also employed to direct nasal swabs by boil and chill method with successful amplification of SeM gene in positive cases (16.7%). The study highlighted the effectiveness of PCR-based diagnostics in enhancing the detection of strangles and advocating the broader implementation of molecular techniques in routine diagnostics, surveillance and epidemiological investigations throughout India.
Key words: Strangles, Streptococcus equi, SeM gene, PCR, Streptococcus species