P. monodon juveniles were sampled from normal and MSGS ponds and were divided into small-negative,
large-negative, small-positive and large-positive groups, depending on the size of the shrimp and
whether they were LSNV-negative or LSNV-positive. Individual shrimp were measured for duration of each
molt stage and molt interval. Levels of MIH1 and CHH1 transcripts were determined from the optic lobe, using
real-time reverse transcriptase–polymerase chain reaction.