Isolation and characterization of Lactococcus garvieae from rainbow trout , Onchorhyncus mykiss, from California, USA

Author(s):  
Khalid Shahin ◽  
Tresa Veek ◽  
Taylor I. Heckman ◽  
Eric Littman ◽  
Kaveramma Mukkatira ◽  
...  
2020 ◽  
Vol 13 (1) ◽  
pp. 53-68
Author(s):  
Vladimir Radosavljević ◽  
Oliver Radanović ◽  
Nemanja Zdravković ◽  
Božidar Savić ◽  
Marko Stanković ◽  
...  

The outbreak of lactococcosis affecting rainbow trout, weighing 70 - 120 g, occurred at a trout aquaculture facility in Central-West Serbia during July, 2018. This outbreak lasted for three weeks, and cumulative mortality attributed to the disease was around 40%. The diseased fish showed erratic swimming, dark discoloration and exophthalmia, with the cumulative mortality of around 40%. A pure Gram-positive cocci isolates were obtained from the eye and kidney samples. Based on colony morphology, phenotypic and biochemical characteristics, the isolated bacterium was presumably identified as Lactococcus garvieae. Using the BBL CRYSTAL GP ID system, the isolate was identified as L. garvieae and the identity of the isolate was confirmed with MALDI-TOF Mass Spectrometry. Blast analysis of 16S rRNA sequence of our isolate had a 99.4 to 99.6% similarity to the L. garvieae strains previously isolated from diseased fish. The antibacterial activity of 15 antimicrobials against L. garvieae was evaluated using disc diffusion. In this paper, we report the first case of lactococcosis in rainbow trout in Serbia, isolation and characterization of causative agent, Lactococcus garvieae from diseased rainbow trout.


1985 ◽  
Vol 17 (2-4) ◽  
pp. 333-334
Author(s):  
R.J. Van Beneden ◽  
D.K. Watson ◽  
R.A. Sonstegard ◽  
T.T. Chen ◽  
T.S. Papas

2008 ◽  
Vol 74 (13) ◽  
pp. 4070-4078 ◽  
Author(s):  
Anne Rønnest Stenholm ◽  
Inger Dalsgaard ◽  
Mathias Middelboe

ABSTRACT Flavobacterium psychrophilum is a serious pathogen in trout aquaculture, responsible for the diseases rainbow trout fry syndrome (RTFS) and cold water disease (CWD). Bacteriophage control of F. psychrophilum may constitute a realistic approach in the treatment of these diseases; however, a detailed understanding of the phage-host interactions is needed to evaluate the potential of F. psychrophilum bacteriophages for that purpose. Twenty-two F. psychrophilum phages from Danish rainbow trout farms were isolated and characterized. The phage genome sizes differed considerably and fell into three major size classes (8.5 to 12 kb, 48 kb, and 90 kb). The phage host ranges comprised from 5 to 23 of the 28 tested F. psychrophilum strains, and 18 of the phage isolates showed unique host ranges. Each bacterial strain had a unique pattern of susceptibility to the 22 phages, and individual strains also showed large variations (up to 107-fold differences) in susceptibility to specific phages. Phage burst size (7 to 162 phages infected cell−1) and latency period (4 to 6 h) also showed pronounced differences both between phages and, for a specific phage, between host strains. In general, the characterization documented the presence of diverse F. psychrophilum phage communities in Danish trout farms, with highly variable patterns of infectivity. The discovery and characterization of broad-host-range phages with strong lytic potential against numerous pathogenic F. psychrophilum host strains thus provided the foundation for future exploration of the potential of phages in the treatment of RTFS and CWD.


1990 ◽  
Vol 14 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Takashi Murai ◽  
Hiroshi Kodama ◽  
Masaharu Naiki ◽  
Takeshi Mikami ◽  
Hisao Izawa

Sign in / Sign up

Export Citation Format

Share Document