Isolation, Characterization and Identification of Gut Bacteria from Piscine Ectoparasite Argulus bengalensis (Ramakrishna 1951) and their Relationship with Haematophagy

Abstract

Gut microbiome plays a pivotal role in health and nutrition of mostorganisms.
Argulus bengalensis is a haematophagus ectoparasite of fresh water carp and
its infection causes extensive damage to fish farms. Thepresent study aims at
isolation, characterization and identification of the gut bacteria from Argulus
bengalensis and to decipher its potential contribution in haematophagy of the
parasite. The gut bacteria were isolated, cultured and identified based on
analyses of its morphological, physiological and biochemical features as well
as 16s rRNA analyses against the NCBI genetic database. Antibiotic
sensitivity of the bacterial strains was tested. Haemolytic activity and ability
of the isolates to produce anticoagulant substance were also tested to justify
the hypothesis. Two isolates were identified to be similar type strains of
Acenatobacter baumanii and Aeromonas hydrophila respectively which have
accession number MW811800 and MW806655 respectively. Both bacteria
were found sensitive to most antibiotics. Both Acenatobacter baumanii and
Aeromonas hydrophila showed their haemolytic activities and able to secrete
anticoagulant substances establishing their mutualistic association which
increase the fitness of the parasitic host facilitating haematophagy. The
outcome of the study thus may provide a scientific direction to develop novel
methods to control of argulosis