My dog has spots like that too, i think it comes from running through long wet grass at this time of year, if it gets out of hand and too itchy or weepy, i wash him in head and shouders shampoo, it really cools his skin and drys up the rash better than anything i have ever got from the vet. He also has a small umbilical hernia for all his life (he is 10 years old now). It is very small but your dogs one looks bigger, i that was my dog i would have an opinion from another vet, i wouldn't like to have to deal with an emergency strangulation etc, or indeed that catching on anything.
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