Are Soays more difficult to castrate? YES ! Soay testes are tiny - even if you do get the ring on, they can pull back through which would be painful and also leave you with a rigg. Legally the rings have to be applied within 7 days but this is presumably an average for big commercial breeds. Luckily both our Soay tup lambs are being left entire this year, but I know that many Soay breeders don't try to put the rings on until 3 weeks.