Last week I had (maybe 6 month old?) guinea hen go from being perfectly normal, to staying a little puffed up for a couple of days to looking a little lethargic and doing a slight neck "s curve" wiggle in about 3 days. By the fourth day the neck wiggle got to be pretty violent and it seemed to me like she was having trouble getting food down because of something going on with her crop or neck. As soon as I saw the slight neck wiggle on that first day I started massaging her crop to see if something was impacted or if she had sour crop. I did get a couple of smelly burps out of her but she felt empty otherwise. Today I noticed another young hen doing a slight neck wiggle. Any advice? I should mention that the first hen died by the end of the week.