I’m about to do food-sensing assays for my worms. The only part of the protocol I don’t get is why normal bacterial lawns are not spread, but instead a ring shaped lawn is spread. What’s its purpose? Can anybody help?
Many thanks!!!
A literature reference would probably help to clarify; there are a lot of different food-response assays.
Maybe you mean the assay of Sawin (sometimes called the Mod assay), which is used to examine the effect on locomotion rate of encountering food? In this assay, animals are deposited in the cleared area in the middle of the ring, excess liquid is removed, and animals are only scored if they reach the ring of food. Thus, animals damaged by the transfer process and animals disinclined to move from the spot at which they were deposited don’t have to be considered.