"Food is any substance, usually composed primarily of carbohydrates, fats, water and/or proteins, that can be eaten or drunk by an animal for nutrition and/or pleasure." On Food and Cooking: The Science and Lore of the Kitchen
Keeping your pet happy is important. Why? At lower levels, making sure your pet is well fed means that it is gaining loyalty - and with loyalty comes training points (See: Beast Training, a How-To Guide). By feeding a pet, its happiness increases. A pet has three different states of happiness: Happy (where the pet deals 125% damage), Content (where the pet deals 100% damage) and Unhappy (where the pet deals 75% damage). Ideally, a hunter's pet should always be 'happy'.
Every beast has a specific diet. That means that if you try to feed your cat a piece of fruit, it will refuse to eat it - however, a gorilla will happily gobble it down. To determine what sort of diet your pet has, you can either use the spell 'Beast Lore,' or you can mouse over the happiness icon in the pet's character pane. There are 6 different types of food available: Bread, Cheese, Fish, Fruit, Fungus and Meat (as well as Raw Fish and Raw Meat, although for all intensive purposes, Fish and Meat are the same cooked as uncooked). Not all beasts eat every type of food, so ease of obtaining foodstuffs may be a consideration to take into account when choosing an animal companion. The breakdown is as follows:
Bread
Bear
Boar
Crawler
Sporebat
Wind Serpent
Cheese
Bear
Boar
Sporebat
Tallstrider
Wind Serpent
Fish
Bear
Boar
Wind Serpent
Crawler
Turtle
Dragonhawk
Warp Stalker
Carrion Bird
Cat
Crocolisk
Serpent
Fruit
Bear
Boar
Sporebat
Crawler
Tallstrider
Turtle
Dragonhawk
Warp Stalker
Gorilla
Bat
Hyena
Fungus
Bear
Boar
Sporebat
Crawler
Tallstrider
Turtle
Gorilla
Bat
Meat
Bear
Boar
Dragonhawk
Carrion Bird
Cat
Crocolisk
Serpent
Hyena
Raptor
Owl
Wolf
Spider
Scorpid
Nether Ray
Ravager
As the list shows, some beasts, such as wolves, eat only meat. Others, like bears, will eat any type of food available.
Keep in mind, that a pet does not need to be force fed. Allow it to finish eating one piece of food before giving it another (when a pet is fed, it will gain an icon under its portrait that says 'Feed Pet effect' - once this vanishes, another piece of food can be given to the pet. This can also be monitored in the chat window, under 'Periodic Effects' then 'Your Periodic Buffs'). Once a pet becomes happy, feeding can stop. A pet's happiness will go down over time, although opinions vary whether this occurs quicker if you are fighting or not.
Happiness from food scales like everything else - low quality food gives 8 happiness each 'bite'. The best quality food gives 35 happiness each 'bite'. As a pet gains levels, it will need higher quaility food for it to become happy. The higher quality the food, the more happiness your pet gets with every bite. A level 70 pet will turn up its nose at level 10 food. Conversely, a LV10 pet doesn't need to be fed LV70 food. The secondary tradeskills Cooking and Fishing can both be very useful to the Hunter. Cooking food (using pieces of meat dropped by various NPCS for example) will turn it into higher quality foodstuffs than if the meat was simply fed to the pet without cooking it.
Tip: There are several tricks available for pets that consume certain types of food. Bread eaters (Bear, Boar, Crawler, Sporebat and Wind Serpent) can be provided with mage summoned foodstuffs. Keep in mind that if you rely on this, it means that you will need to know a friendly mage or three to ensure your supply doesn't run out while you play, since summoned food doesn't last for extended periods if you logout of the game.
Fish eaters (Bear, Boar, Wind Serpent, Crawler, Turtle, Dragonhawk, Warp Stalker, Carrion Bird, Cat, Crocolisk and Serpent) can be fed from what you catch using the Fishing ability. Alternatively, peruse the Auction House under the 'Consumeables' category. People often put up stacks of fish (both raw and uncooked) at a less expensive price than one could purchase it from a vendor. Blackened Trout, for example, runs around 60s-1g per stack on the Auction House (prices vary per server). Buying similiar level food from a vendor costs over 2g!
There are also a few items that will summon food. The Staff of Conjuring (a rare drop from the Defias Conjurer) summons bread and the Everlasting Underspore Frond (quest reward) summons fruit.
Without taking into account faction related discounts, food from vendors are sold in stacks of 5 pieces per. The cost rises 25c, 1s25c, 5s, 10s, 20s, 40s, 56s, 64s, 80s, with 80s being the cost for 5 pieces of the highest quality food currently available.
Pets do not gain bonuses from eating food, even if said food says that that it provides a bonus once consumed - this only applies to player characters. The single exception to this is an item called a Sporeling Snack. It is a cooking recipe sold by Mycah, the Sporeggar Quartermaster in Zangarmarsh and requires Strange Spores. The snack increases the Stamina and Spirit of your pet by 20 and lasts for 30 minutes. Make sure you right click this item, feeding it to your pet via the 'Feed Pet' ability will not have the same effect (in fact, the message should appear that your pet doesn't like that food).
The following vendors sell the various foodstuffs a pet might need. Vendors listed on both factions are ones such as Cenarion Circle who do not discriminate.
FULL LIST COMING SOON!
Meat:
Sognar Cliffbeard (Military Ward, IF)
Innkeeper Firebrew (Stonefire Tavern, IF)
Nipsy (Deeprun Tram)
Toddrick (Lion's Pride Inn, Elwynn Forest)
Bartender Wental (Lakeshire Inn, Redridge Mountains)
Sherman Femmel (Lakeshire Inn, Redridge Mountains)
Master Smith Burninate (Thorium Point, Searing Gorge)
Innkeeper Helbrek (Deepwater Tavern, Wetlands)
Targot Jinglepocket (Refuge Point, Arathi Highlands)
Narj Deepslice (Refuge Point, Arathi Highlands)
Bront Coldcleave (Southshore, Hillsbrad Foothills)
Truk Wildbeard (Wildhammer Keep, Hinterlands)
Jaeana (Tradesmen's Terrace, Darnassus)
Ulthaan (Silverwind Refuge, Ashenvale)
Innkeeper Vizzie (Everlook, Winterspring)
Himmik (Everlook, Winterspring)
Craig Nollward (Theramore Isle, Dustwallow Marsh)
Dwane Wertle (Theramore Isle, Dustwallow Marsh)
Chylina (Stonetalon Peak, Stonetalon Mountains)
Bread:
Alexander Calder (Forlorn Cavern, IF) * Special
Sraaz (The Great Forge, IF)
Inkeeper Belm (Thunderbrew Distillery, Dun Morogh)
Thomas Miller (Trade District, Stormwind)
Innkeeper Allison (The Gilded Rose, Stormwind City)
Orphen Matron Nightingale (Cathedral Square, Stormwind City) *Special
Kira Songshire (Elwynn Forest)
Innkeeper Hearthstove (Stoutlager Inn, Loch Modan)
Honni Goldenoat (Stoutlager Inn, Loch Modan)
Greishan Ironstove (Loch Modan)
Mike Miller (Sentinel Hill, Westfall)
Farmer Saldean (Saldean's Farm, Westfall)
Nixxrax Fillamug (Salty Sailor Tavern, Stranglethorn Vale)
Gretchen Vogel (Lakeshire, Redridge Mountains)
Bartender Wental (Lakeshire Inn, Redridge Mountains)
Neema (Southshore, Hillsbrad Foothills)
Innkeeper Anderson (Southshore, Hillsbrad Foothills)
Innkeeper Thulfram (Wildhammer Keep, Hinterlands)
Innkeeper Keldamyr (Dolanaar, Teldrassil)
Danlyia (Dolanaar, Teldrassil)
Lyrai (Aldrassil, Teldrassil)
Kyndri (Auberdine, Darkshore)
Nantar (Astranaar, Ashenvale)
Innkeeper Janene (Theramore Isle, Dustwallow Marsh)
Craig Nollward (Theramore Isle, Dustwallow Marsh)
Dwane Wertle (Theramore Isle, Dustwallow Marsh)
Innkeeper Lyshaerya (Nijel's Point, Desolace)
Fruit:
Bimble Longberry (Mystic Ward, IF)
Homer Stonefield (Stonefield Farm, Elwynn Forest)
Corporal Bluth (Rebel Camp, Stranglethorn Vale)
Lamar Veisilli (Lakeshire, Redridge Mountains)
Targot Jinglepocket (Refuge Point, Arathi Highlands)
Innkeeper Saeliennne (Craftsmen's Terrace, Darnassus)
Allyndia (Auberdine, Darkshore)
Maliynn (Astranaar, Ashenvale)
Dwane Wertle (Theramore Isle, Dustwallow Marsh)
Cheese:
Ben Trias (Trias' Cheese, Stormwind City)
Elaine Trias (Trias' Cheese, Stormwind City)
Innkeeper Farley (Lion's Pride Inn, Elwynn Forest)
Barkeep Dobbins (Lion's Pride Inn, Elwynn Forest)
Innkeeper Trelayne (Scarlet Raven Tavern, Duskwood)
Bartender Wental (Lakeshire Inn, Redridge Mountains)
Gabrielle Chase (Morgan's Vigil, Burning Steppes)
Neema (Southshore, Hillsbrad Foothills)
Innkeeper Anderson (Southshore, Hillsbrad Foothills)
Truk Wildbeard (Wildhammer Keep, Hinterlands)
Craig Nollward (Theramore Isle, Dustwallow Marsh)
Dwane Wertle (Theramore Isle, Dustwallow Marsh)
Fish:
Khara Deepwater (The Loch, Loch Modan)
Innkeeper Heather (Sentinel Hill, Westfall)
Innkeeper Skindle (Salty Sailor Tavern, Stranglethorn Vale)
Vernon Hale (Lakeshire, Redridge Mountains)
Gretchen Vogel (Lakeshire, Redridge Mountains)
Innkeeper Brianna (Lakeshire Inn, Redridge Mountains)
Stuart Flemming (Menethil Harbor, Wetlands)
Hal McAllister (Southshore, Hillsbrad Foothills)
Talaelar (Tradesmen's Terrace, Darnassus)
Laird (Auberdine, Darkshore)
Heldan Galesong (Twilight Shore, Darkshore)
Himmik (Everlook, Winterspring)
Kilxx (Ratchet, The Barrens)
Innkeeper Wiley (Ratchet, The Barrens)
Fungus:
Scott Carevin (Darkshire, Duskwood)
Targot Jinglepocket (Refuge Point, Arathi Highlands)
Janet Hommers (Nijel's Point, Desolace)
Other (Bean Soup, Versicolor Treat, Steamed Mandu, Wild Ricecake, Heaven Peach, Darnassus Kimchi Pie, Radish Kimchi, Cabbage Kimchi, Winter Kimchi. Please note: Steamed Mandu, Heaven Peach and the Kimchis appear to be classified as fruit. The Ricecake and Bean Soup, bread. And the Versicolor Treat, don't ask me why, seems to be cheese):
Danlyia (Dolanaar, Teldrassil)
Dellylah (Aldrassil, Teldrassil)
Dendrythis (Cenarion Enclave, Darnassus)
Allyndia (Auberdine, Darkshore)
Tiyani (Grove of the Ancients, Darkshore)
Maliynn (Astranaar, Ashenvale)
My'lanna (Nighthaven, Moonglade)
Dargon (Nighthaven, Moonglade)
Innkeeper Vizzie (Everlook, Winterspring)
Lyranne Feathersong (Starfall Village, Winterspring)