I have had goats for 40 yrs and have never seen this. Usually goats are very picky about what they eat and won't eat things that are not good for them ( except things like wire, nails, no idea why they do that, If they do they will stop eating and get skinny and eventually starve to death.
Give them a magnet you can get from the feed store for that purpose and put that down them with a pill plunger and some antibiotics for a few days, they will be fine).
Be sure your goats are getting enough to eat of the proper food. If they are hungry and no other food is available they will eat what is available even if they ordinarily wouldn't. What are they eating? Hope you have figured this one out.
Old Goat Lady
Jul 30, 2010 Rating
Vomiting Goats and Toxins by: Countryfarm Lifestyles
Vomiting in goats is a good thing as it sounds as if your goat has eaten something poisonous and it is trying to get rid of the toxins.
Usually this happens when goats are allowed into the garden and they eat plants that are toxic for them such as azaleas and rhododendrons.
Feeding your goat some crushed charcoal will help alleviate the situation by binding the toxins. Also try to get your goat to take some olive oil as this will help coat the stomach wall, and some water if your goat looks dehydrated. I would also get hold of your vet.