437
Pathogenicity
Experimental challenges with scarifi ed rohu involving i.m. injection with 0.1 ml
containing 2.0 × 10
7 cells/fi sh led to the development of tail erosion within 36 h,
with mortalities recorded 24 h later (Adikesavalu et al. 2015 ). Additional groups
were bathed in a suspension of the Flectobacillus at ~2.0 × 10
6 bacteria/ml.
Flexibacter spp.
The fi sh pathology literature abounds with references to unspeciated Flexibacter.
Pyle and Shotts ( 1980 , 1981 ) studied 17 strains for phenotypic traits, as determined
by use of the API 20E rapid identifi cation system, and by DNA homology. The
conclusion reached was that the isolates from warm-water fi sh were distinct to those
recovered from cold-water fi sh. At least three separate groups were recognised.
However, whether or not these organisms belong in existing species or represent
new taxa must await further study.
Myroides odoratimimus
In this case, cultures obtained from the gut of healthy grey mullet (Mugil cephalus),
and which demonstrated pathogenicity in laboratory experiments with healthy fi sh
(Ravindran et al. 2015 ). Time will tell if this going to be emerging pathogen.
Characteristics of the Disease
Experimental challenge resulted in anorexia and abnormal swimming behaviour
with rapid breathing within 1–2 days. This was followed by lethargy with the fi sh
stationary at the bottom or swimming close to the surface. Skin haemorrhaging was
observed, and reddening on the abdomen, mouth and pectoral fi ns. Later, black
patches developed on the skin, and eye haemorrhages were seen.
Isolation
Gut contents were inoculated onto marine 2216E (marine/Zobell’s) agar, nutrient
agar and TSA with incubation at an undisclosed temperature for an unstated period,
the outcome of which was the recovery of pure cultures.
Myroides odoratimimus
Pathogenicity
Experimental challenges with scarifi ed rohu involving i.m. injection with 0.1 ml
containing 2.0 × 10
7 cells/fi sh led to the development of tail erosion within 36 h,
with mortalities recorded 24 h later (Adikesavalu et al. 2015 ). Additional groups
were bathed in a suspension of the Flectobacillus at ~2.0 × 10
6 bacteria/ml.
Flexibacter spp.
The fi sh pathology literature abounds with references to unspeciated Flexibacter.
Pyle and Shotts ( 1980 , 1981 ) studied 17 strains for phenotypic traits, as determined
by use of the API 20E rapid identifi cation system, and by DNA homology. The
conclusion reached was that the isolates from warm-water fi sh were distinct to those
recovered from cold-water fi sh. At least three separate groups were recognised.
However, whether or not these organisms belong in existing species or represent
new taxa must await further study.
Myroides odoratimimus
In this case, cultures obtained from the gut of healthy grey mullet (Mugil cephalus),
and which demonstrated pathogenicity in laboratory experiments with healthy fi sh
(Ravindran et al. 2015 ). Time will tell if this going to be emerging pathogen.
Characteristics of the Disease
Experimental challenge resulted in anorexia and abnormal swimming behaviour
with rapid breathing within 1–2 days. This was followed by lethargy with the fi sh
stationary at the bottom or swimming close to the surface. Skin haemorrhaging was
observed, and reddening on the abdomen, mouth and pectoral fi ns. Later, black
patches developed on the skin, and eye haemorrhages were seen.
Isolation
Gut contents were inoculated onto marine 2216E (marine/Zobell’s) agar, nutrient
agar and TSA with incubation at an undisclosed temperature for an unstated period,
the outcome of which was the recovery of pure cultures.
Myroides odoratimimus