Sounds like they are drinking a lot of water--I would trust their judgement, and let them do that.
If the feed has too much salt (manufacturing mistake), they could be extra-thirsty and drinking a lot, and feeling ill.
If the feed has something else wrong with it, and made them ill, they may be drinking lots of water because they're hungry but afraid to eat the feed. Or drinking a lot to try to flush the problem out of their systems.
(Of course, there are lots of other possible explanations too.)
New feed, and access to as much water as they want, is probably a sensible approach right now.
Have you got new feed for them yet? If so, did they act interested in eating it?
If the feed has too much salt (manufacturing mistake), they could be extra-thirsty and drinking a lot, and feeling ill.
If the feed has something else wrong with it, and made them ill, they may be drinking lots of water because they're hungry but afraid to eat the feed. Or drinking a lot to try to flush the problem out of their systems.
(Of course, there are lots of other possible explanations too.)
New feed, and access to as much water as they want, is probably a sensible approach right now.
Have you got new feed for them yet? If so, did they act interested in eating it?