Domestication

• WWizards of the Coast2010-06-15
  Official Ruling
  Domestication's triggered ability has an "intervening 'if' clause." That means (1) the ability triggers only if the enchanted creature's power is 4 or greater as your end step begins, and (2) the ability does nothing if the enchanted creature's power is 3 or less by the time it resolves.
• WWizards of the Coast2010-06-15
  Official Ruling
  Domestication can target, and can enchant, a creature with power 4 or greater. The enchanted creature's power is checked only when the triggered ability triggers and resolves.
• WWizards of the Coast2010-06-15
  Official Ruling
  If an effect changes the enchanted creature's power until end of turn, it will still have the modified power during your end step.

Rulings via Scryfall