Shrimp farmers used to hold animals in nursery ponds for 30 to 60 days; now they try to move them into grow-out ponds in less than 30 days. This reduces stress on the animals and dramatically increases survivals in the grow-out ponds. Many farms that abandoned nursery ponds have gone back to them, and the results have been surprisingly positive. They're using the old, uncovered, earthen, nursery ponds.
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