HELP! there is something wrong with my chicken's neck when swallowing!

[sus9441]

PLEASE HELP!
if you view the video, the new plymouth barred rock is behaving oddly when it is swallowing pullet grower (slightly soaked) pellets. Now, another chick I have is having the same behaviour!!
what does this odd behaviour mean???

 

[Eggcessive]

I don't have a good answer, but I wonder if they are adjusting their crops? The pellets look a little large for them, could they be having trouble swallowing them? I have been using Nutrena Naturewise layer pellets lately, and they are a smaller size than other brands.