Hi there...there can be quite a variation in what is "normal" for an 8 week cocker spaniel. I would guess on average that most I see would be about 5-8 lbs. If you are concerned that this dog is too thin or too heavy the best thing to do would be to feel the ribs. You should be able to feel them with a little covering overtop. If they are obviously protruding then the dog may be too thin. If you can't find them then the dog is overweight.
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