Outbreak of Abortions and Infertility in Thoroughbred Mares Associated with Waterborne Aeromonas hydrophila

Abstract

At a thoroughbred equine breeding farm near Hissar (Haryana), three mares aborted in their seventh month of pregnancy. The vaginal swabs of all aborted mares, and stomach contents, heart blood, liver, spleen and placenta of aborted fetuses yielded pure culture of Aeromonas hydrophila. In addition, A. hydrophila was also isolated from the vaginal swabs of three repeat breeding mares and faecal sample of a diarrheic foal. The source of infection was possibly water supply as all the water samples collected from taps, mother tank and storage tank were found to be positive for A. hydrophila. The antibiogram of all the isolates was similar showing resistance to ampicillin, carbenicillin, gentamicin, kanamycin and amikacin but sensitive to chloramphenicol, ciprofloxacin, cefuroxime, ceftriaxone, cotrimoxazole, cotrimazine, nitrofurantoin, streptomycin and tetracycline. All the 20 sera samples collected from three aborted and three repeat breeding, and eight in-contact mares, a diarrheic foal, three cows and two male buffaloes maintained at the same farm contained antibodies against A. hydrophila with titres ranging from 80 to 640. The water supply was instantly chlorinated using 0.05% sodium hypochlorite for three consecutive days and all the culturally positive mares were treated with intravaginal administration of 1 g ciprofloxacin, while the foal was given nitrofurantoin for three days. After one month, A. hydrophila could not be isolated either from mares or from their environment and antibody titre in all the seropositive animals showed a declining trend. Later, all the aborted and repeat breeding mares were confirmed to be pregnant. Thus, the present study indicated that water-borne A. hydrophila might be associated with equine abortions and infertility, and diarrhea in newborn foals.

Isolation of a lytic bacteriophage against virulent Aeromonas hydrophila from an organized equine farm

“…Many extracellular products of A. hydrophila such as aerolysin, enterotoxins, protease, and acetylcholinesterase have been considered as virulence factors in pathogenesis . The aerolysin and lipase gene products were detected in our A. hydrophila isolate, suggesting its pathogenic potential in the farm environment, which is in correlation with the previous study , where, however, the pathogenic indulgence of A. hydrophila was not determined at molecular level.…”

“…Out of 20 phages (enlisted in NCBI) responsible for infecting Aeromonads, only Aeromonas phage Aeh1 and phage CC2 are known to infect A. hydrophila . Looking at the implications regarding persistence of such a microbe in equine environment , we attempted to isolate phage against an equine farm isolate of A. hydrophila from the sewage of the same farm. A lytic phage was successfully recovered which belonged to family Myoviridae.…”

“…However, there have been very few reports regarding isolation and characterization of T4 or T4‐like phages infecting Aeromonas hydrophila which is considered as a potential pathogen for aquatic and terrestrial environments . Additionally, its virulence potential has also been assessed in humans and has been related with abortion in equines . In the present study, we isolated a pathogenic strain of A. hydrophila and corresponding bacteriophage from the sewage of an organized equine farm, which could serve as a biocontrol agent.…”

Contribution of the EnvZ/OmpR two-component system to growth, virulence and stress tolerance of colistin-resistant Aeromonas hydrophila

“…Aeromonas hydrophila , an opportunistic aquatic pathogen that causes various diseases in both aquatic and terrestrial species, has attracted considerable attention owing to its high pathogenicity. It causes serious diseases in animals ( Singh et al, 2011 ; Igbinosa et al, 2016 ; Liu et al, 2019 ) and humans ( Zhang et al, 2012 ; Ventura et al, 2015 ), and is one of the most common pathogens posing serious public health problems. Survival and adaptation to hostile conditions can enhance and repress the expression of certain characteristics ( Tsai et al, 1997 ; Boor, 2006 ; Mcmahon et al, 2007 ), promoting the survival of A. hydrophila in various environments.…”

Random compound mutagenesis breeding of Bacillus amyloliquefaciens X030 with high resistance to pathogenic bacteria on grass carp

“…The rapid development of aquaculture leads to the disease problem of aquatic animals becoming increasingly prominent. Bacterial infectious diseases that caused by Aeromonas hydrophila (A. hydrophila) (Singh et al 2011;Pridgeon and Klesius 2011) and Aeromonas veronii (A. veronii) (Smyrli et al 2019;Zhang et al 2020) had huge harm to sheries in the whole world. In recent years, biological agents had more attention as the substitute for chemical pesticides.…”