WHAT TO FEED YOUR PIGGY
BACK
If you have noticed the cavy, it is usually munching on something all
the time.  The reason is, they metabolize their food so quickly that if
they don’t keep something in their stomach it will cause gas production
and intestinal bloating (gastroenteritis) which can be extremely
uncomfortable.  The pain can then cause guinea pigs to refuse to eat,
which in turn leads to lethargy and will eventually lead to death.  

Oxbow’s Cavy Cuisine
It’s a timothy based pellet with stabilized vitamin C and chock full of
nutrition.  It has the least amount of fat as any that I have seen on
the market and better than most.  Hartz guinea pig pellet has no less
than 3% fat, Mazuri has no less than 4%, while Cavy Cuisine has only
1.5%, thus your pigs will not get near as obese.

Prairie Grass Hay
Hay is in their cage and available for them to eat at all times because
its one of the most important things in their diet.  It provides fiber to
aid in the digestion of their food, helps to grind down their teeth and
keeps them from getting gastroenteritis (because it always provides them
something to munch on).

Fruits and Vegetables
Available only because they like it, not because they need the extra
nutrition.  I believe that if they are fed a top of the line pellet, its like
feeding them vitamins.  They love their carrots and lettuce, so they get
a portion, plus a different fruit everyday.

There are, however, certain vegetables that really shouldn't be fed to a
pig.  When we eat foods that are high in oxalic acid, this oxalic acid
connects itself to other nutrients from our bodies, such as sodium,
magnesium, potassium, calcium and iron to produce what is called
oxalate, (otherwise known as salt).  This is why when you sweat it
tastes like salt.  High levels of oxalate in the body (from foods that
are rich in oxalic acid), can form tiny crystals with sharp edges that
can irritate the digestive system and kidneys (which in turn forms kidney
stones - the most common type being calcium oxalate).  

Too much oxalic acid in your system can also unite with other nutrients
making the body unable to absorb them, thus leading to nutritional
deficiencies - especially calcium.  Pregnant sows in particular are at risk
for hypocalcemia so it would be best to avoid foods that are high in
oxalic acid.

“foods such as spinach, rhubarb, peanuts, grapefruit, strawberries, wheat
bran, parsley and chives contain large amounts of oxalate and should be
avoided.” (quoted directly from the USDA)
FOODS KNOWN TO HAVE HIGH AMOUNTS OF OXALATES

Most berries (such as): cranberries, blackberries, blueberries
and strawberries.

Most nuts (such as): cashews, almonds, peanuts and walnuts.

Vegetables:  green peppers, sweet potatoes, red and white cabbage, celery,
potatoes,beets, swiss chard, summer squash, mustard greens and most all
beans.

*Popcorn, nuts and seeds should be avoided as well, because it’s
the same principle as feeding chicken bones to a dog, and it might
be best to avoid known gas producers such as cabbage, broccoli
and cauliflower or perhaps to be given as a treat once in a while.

If you have any question about the content of any one fruit or vegetable,
please consult the USDA Nutrient Data Lab or the
USDA Nutritional Content of Food(pdf-opens in new window), and don't go
by word of mouth. You don’t know where people get their information from
and it’s quite possible that you are passing along an untruth.