The study was conducted from August 2014 through January 2015.
Cyprinid freshwater fish were obtained from endemic areas in
Mukdahan province, northeastern Thailand, and in Khammouane
province, Laos. These fish were placed in an icebox and transported to
the laboratory. Wild fish species that could likely be contaminated
with OVMC – including Cyclocheilichthys armatus, Puntius orphoides,
Hampala dispar, Henicorhynchus siamensis, Osteochilus hasselti and
Puntioplites proctozystron (Pinlaor et al., 2013) – were selected and
included in the study. At least eight kilograms of fish was used and
randomly divided into two experimental groups. Fish in the first
group was used to investigate the effect of pla-som fermentation time
on the viability and infectivity of OVMC. Fish in the second experimental
group was used to investigate the viability and infectivity of OVMC
isolated from pla-som kept at a low temperature (4 °C). In addition,
OVMC obtained from freshwater fish without fermentation was used
as an uncooked control. All experiments were performed in duplicate.