My boar (Genie) is much older than my sow (Daphne) and he has always been the dominant one (by default more than by nature). He is 5 years old now and I'm worried her move for dominance is a sign of his health declining. He can't run as fast as her anymore and can't keep up to try and get on top of her. Should I be worried? Does this mean he's dying? Any answers for a very concerned pig mum would be appreciated.