I was reluctant to get my lone boar Bumble nuetered as I really didnt want to take the risk,call it womans intuition but I really have an uneasy feeling about it where he is concerned,I mean a real sort of twighlight zone feeling - so instead I went on the waiting list for a spayed sow from Tracy @ Rugby Rabbit & Guinea Pig welfare - they really do have one of the top vets in the country there (Simon Maddock who treats the dental piggies from The Excellent Adventure Sanctuary ) - so he literally has done hundreds.
The reason Rugby spay all their females is because it guarantees they cannot be bred from in future - it costs £180 for them to spay a sow (one operates ,one anethetises,nurses assist etc ) so when you pay £35 for your spayed female you really are getting a "bargain" as the rescue have had to foot the other £145 for the cost of the op - I think this may also have something to do with the wait for a spayed sow as my two spayed females (a bonded pair who are very bossy wifepigs to their toyboy huspig Bumble came into rescue in June/ July last year and I picked them up in January - )the rescue can obviously only spay when they have the funds available to do so - they also do not spay (usually) at certain times of the year I think it was October - New year / march,but that may be subject to change -