Free-living nematode larvae
Many nematode parasites have free-living larval stages that are found in the host environment. The first two stages (L1 & L2) are usually feeding stages while the third stage (L3) is the infective stage for the host and does not feed. The L4 & L5 stages are usually parasitic, However, you must be aware of nematode species that don't play by these rules eg the infective stage of many lungworm species is the L1 stage.
- L1 & L2 larval stages
- L3 larval stage