How old are the puppies?
Are the eyes open, do they appear to be blind?
Yes it's true, dogs do not get cerebral palsy. However, they can have neurologic problems related to the cerebrum, cerebellum, or brain stem.
It's very difficult to say if the signs you are noticing are true neurologic deficits, or if they are simply due to the fact that these little ones are smaller and weaker than the others. The scissoring specifically can be a result of true ataxia, or may just be because their muscles aren't strong enough to keep a normal posture at all times and correct when they have their feet misplaced.
I would have to see the spasms to better understand them. It could be something as simple as hiccups, or it could be a signs of neurologic disease.
I recommend having these two evaluated by a vet. This will give you a better idea if these two are truly "special", or if they are just wee runts that need a little extra help to catch up and grow normally.
I hope this helps. Good luck with the little ones.
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