Tovuqlar kolibakteriozining zamonaviy diagnostikasi: klassik bakteriologiyadan molekular-genomik yondashuvlargacha

Abstract

Avian colibacillosis is a complex of bacterial diseases causing significant economic losses in poultry production and is primarily associated with avian pathogenic Escherichia coli (APEC) isolates. Diagnosis is challenging because E. coli is a normal component of the intestinal microbiota of healthy birds, while APEC is genetically heterogeneous and lacks a single serotype or universal virulence marker that encompasses all pathogenic isolates. This narrative-critical review analyzes the diagnostic capabilities and limitations of clinical and pathological assessment, pathological sample selection, conventional bacteriological and biochemical identification, serotyping, MALDI-TOF MS, PCR and multiplex PCR, LAMP, MLST, and WGS. The diagnostic relevance of molecular panels targeting iutA, hlyF, iss, iroN, ompT, sitA, traT, and other virulence-associated genes is also considered. Current evidence indicates that APEC cannot be reliably identified on the basis of a single gene or serotype. Therefore, etiological assessment should integrate clinical and pathological findings, isolation of E. coli from appropriate lesions, molecular characterization of virulence profiles, and antimicrobial susceptibility testing. The review also examines studies from Uzbekistan on conventional bacteriological and serological diagnosis of avian escherichiosis, as well as qPCR- and molecular AMR panel-based surveillance of poultry-associated E. coli populations in West Kazakhstan. For future research in Uzbekistan, the integration of standardized multiplex PCR, MLST, and WGS with clinical and epidemiological metadata is proposed as an important direction for characterizing APEC according to modern molecular and epidemiological criteria.