Right after being neutered, a dog will act more lethargic, according to Operation Pets. For the first few days following the procedure, the dog will likely sleep more and walk slower.
A dog also typically has less of an appetite for days following surgery. As the dog recovers, his appetite will start coming back a little at a time. He should still be offered food on a regular basis to encourage eating. Since the healing process can take up to 2 weeks, some dogs will not return to normal for some time. After the incision has healed, most dogs tend to appear calmer than before and may spend less time roaming.