I am performing slow killing assay using Pseudomonas aeruginosa (PAO1) strain and transposon mutants of PAO1. I am using C elegas N2 bristol as the worm model and
E. coli OP50 as a negative control of infection. I transferred 30 adult worms onto each assay plates and started scoring for dead worms every 12 hours
After 48 hours there was new progeny of worms on both PAO1 and the E. coli plates. Is it usual? How can I trouble shoot this or do I need to trouble shoot this issue at all?
The new progeny grows into new adult worms and it is impossible to distinguish the old and new worms. Moreover the number of new worms are very high.
Is there anyway to avoid this in the scoring method and data analysis?
Your problem is completely normal. You can either move the parents every 12-24 hours to avoid the progeny confounding your issue or use mutants or RNAi that remove
the germ line. cdc-25.1 RNAi or glp-1 mutants are good options:
http://www.ncbi.nlm.nih.gov/pubmed/18370169
These germline-less animals will have extended lifespans on E. coli and P. aeruginosa, which you should keep in mind.