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Hi Wildwood- no his lump only became visible last night (developed was a bit misleading) he is quite fluffy so I wouldn't have particularly noticed any sooner, also he won't let me pet him without scratching so I wouldn't have felt it either, but the vet gave him a thorough check over on Friday, because I thought he may be ill as he is so lazy, but he is just too overweight. I have only managed to get one quick feel of it. Thanks for your adivce though.
Kita -He has been 'done' so I think I will have to put up with his tomcat behaviour!