Detection of virulence and tetracycline resistance determinants in Aeromonas Spps. isolated from Indian Ruho carp (Labeorohita)‎ Frys

Abstract EN

An increasing incidence of multidrug resistance among Aeromonas spp.

isolates, which are fish pathogens and emerging opportunistic human pathogens, has been observed in Indian ruho carp in India.

This can be attributed to the horizontal transfer of genetic elements through plasmids.

(ompW, aha1, lip) virulent genes (75%, 75%, 25%) were all present in (66.7%), (33.3%) A.

sobria, A.

hydrophila strains from thirty Indian ruho carp frys from aquaculture ponds respectively, while none of the isolates were bearing to aero virulence gene.

One to seven resistant plasmids were isolated from all eight virulent and non virulent Aeromonas spp.

showed multi-drug resistance with a molecular weight ranging from (1.1-23 kbp), the plasmid content of each isolate was examined using the alkaline lysis protocol.

The antimicrobial susceptibilities of 8 Aeromonas spp.

isolates from Indian Ruho carp (Labeo rohita) were determined by disc-diffusion testing.

Gentamycin, Ciprfloxacin were the drug of choice in combating the bacterial growth in vitro (100%) sensitivity while high levels of resistance against ampicillin were observed (100%) while nalidixic acid and tetracycline showed some level of resistance (57.1%), (28.6%) respectively.

tet determinant type was determined by amplification using six degenerate primer sets(tetA, B, C, D, E, G).

Genomic and plasmid encoded tetA, tetE were observed while tetG was in coexistence in plasmid DNA only of the same isolate.

Moreover tetE in genomic and plasmid born in the same another isolate were observed, However tetB,C,D were not detected in any of the isolates.

The results indicate that the pond-raised Ruho carp may be a source of pathogenic Aeromonas spp.

and that the potential health risks posed by virulent and multiple antibiotic resistance strains of Aeromonas spp.

should be estimated.