My wife recently encountered what I believe may be a defect with the Feeding Pellets implementation in Agricola for iOS.
During the harvest after round 9 in a four-player game, she started out with 1 Sheep. She had pasture-space to hold more (at least 3 I believe). She also had plenty of food to feed her family that turn already in stock.
First in the field phase, she received a vegetable. During the feeding phase, she used Feeding Pellets to swap one vegetable for one more sheep. She saw that she had two sheep in the pasture and confirmed. Immediately after that, she was back to only 1 sheep, though the vegetable was still gone. She was expecting to have 2 sheep become 3 sheep during the breeding phase, but the sheep she'd traded for via Feeding Pellets had disappeared.
I can provide screennames of all the players in this game, if you have someone that wants to check the game log in the database to confirm, though I imagine it'd be best if I emailed or PM'd the correct admin directly.
If it matters:
1) She's using an iPhone 5S with the latest OS updates.
2) She got the vegetable from a field she planted with Hobby Farmer.