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==Life Cycle==
==Life Cycle==
L1-L3 occurs within the envelope. The L3 then exits the sheath in the small intestine, and then concentrates within the '''Lieberkuhn's gland'''. At this stage they are known as EL3, and have two potential options. Firstly, they may either become '''hypobiotic''', remaining dormant for several months to years. This usually occurs Autumn-Winter.
L1-L3 occurs within the envelope. The L3 then exits the sheath in the small intestine, and then concentrates within the '''Lieberkuhn's gland'''. At this stage they are known as EL3, and have two potential options. Firstly, they may either become '''hypobiotic''', remaining dormant for several months to years. This usually occurs Autumn-Winter in temperate climates and as a result the prepatent period may be extended from approximately 6 weeks to as long as 2 years Alternatively EL3 may evolve directly into LL3. They will then evolve into L4, at which stage they will emerge from a nodule. After emergence of the cyst, L4 transforms into L5. They then transform into adults in the lumen.
Only two anthelminitics have activity against encysted stages of small redworm, a single dose of moxidectin or a 5-day course of fenbendazole. At 8 weeks post treatment with moxidectin EL3 stages are eliminated. Due to widespread resistance to fenbedazole a faecal egg count reduction test is recommended prior to using it for treatment of the encysted stages.
Highest egg shedding is in the Spring months. The larvae, which represent 90% of the population, are at maximal levels in the autumn.
Highest egg shedding is in the Spring months. The larvae, which represent 90% of the population, are at maximal levels in the autumn.