We had a tup lamb years ago which the vet said was a hermaphrodite but on closer exam I could see it wasn't. The urethra, which goes from the bladder to the penis, was wide open, so urine dribbled out along its entire length. That little lad stank of urine, but not faeces, so we kept him clean with a sponge and soap and water. It was not possible to castrate him as the scrotum was divided in two, with the open urethra running between the two halves. We made sure to wean him before he got remotely fruity. He went for slaughter as a lamb rather than as a shearling - he was a Shetland and had grown perfectly well. We still have his skin (Boris, it's called

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If it's faeces you're having to scrub off, then take a closer look and see if the bowel is split open to the air too, as it's possible yours isn't a genuine hermaphrodite either. If the bowel is open I wouldn't try to keep him until slaughter, but if it's just urine it's ok.