I tried googling to see if I could find anything on the kibble size for you (I didn't). But I did come across another forum where someone mentions that their dog likes the k/d kibble mixed with warm water. So, maybe Nikki could eat it even if it was a bit bigger than you'd like? You would probably want to make sure that was ok with the vet first, but it's an idea.
Give him a big hug and kiss for me.
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He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion. -- Author Unknown