In our latest update, plots will be awarded to you as you discover and unlock new animal breeds. The plots become immediately available, even if you do not specifically claim the reward via your Animal Collection. If you observe that nothing happens when you tap on the ’Collect’ button in your Animal Collection User Interface (UI), this means that you have already directly placed your newly earned plots on your farm. Our design team is aware that this may create some confusion and is currently looking into ways to better illustrate plot unlocks and rewards in future game updates.
FarmVille 3 – Animals Game GUIDE