According to the US website FARAD.org, Levamisole is approved for poultry in Australia, with no details given. Neither wormer is listed as approved for use in poultry in the UK. Call about it Monday. Our advice isn't so pertinent for you in the UK.
Mary
You can look up possible egg withdrawal times for the Levamisole and the Ronidazole online, or call your university poultry expert Monday.
Neither drug is approved for use in laying hens here, but your rules may be different.
There's a reason it's labeled for pigeons and not chickens.
Mary