When you have an enchanted item in your hotbar, your health bar, hunger bar and crosshair all change colour. This also occurs with enchanted books, written books, nether stars, potions, Notch's apple, and experience bottles. When you have a spawn egg in your hotbar, your health and hunger bars change colour depending on the colour of the spots on the spawn egg, and your crosshair disappears completely. These both affect all gamemodes besides spectator mode, although in creative mode it only affects the crosshair. If you have an enchanted item and a spawn egg in your hotbar, the item closest to slot 9 will take precedence over the other, and the effect associated with that item will occur.