treating for lice

No need to clip at all.
Worm with an Ivermectin based wormed that will kill the lice and be in the system to kill any hatched eggs thus breaking the cycle.
The other thing to do is to by some Neem Oil (The Neem Team) and use a solution of 5ml Neem 3 ml shampoo and 1 L of hot water and wash over with that solution.
 
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