One option, if you want a more natural diet for your dog is to home cook, and lots of people do this.
Some pets are fed home cooking intentionally, others on an occasional basis via table scraps. In some European countries homemade foods already supply an estimated 35% of cats with 60% of their caloric intake.
When the pet receives more than half its daily calories from table foods, the whole diet should then be formulated to ensure a proper nutrient intake and avoid the dangers of obesity or other health problems.
However, there are some possible disadvantages to this method of feeding, namely..
Inconvenience - There isn't always time, and storage can be a problem
Recipes - Recipes that offer what might be considered a scientifically proven complete diet for a dog are thin on the ground, and you have to be aware that some experts consider that the possibilities of under/overfeeding as well as under/over nutrition are potentially going to cause longer term problems.
Cost - It isn't necessarily cheaper to home cook!
Quantity - How do you know how much to feed? This can be a problem with home cooking
Once you start home cooking, you might find it difficult to wean a pet back onto prepared food should you want to.
Here is a quote from the Canadian Veterinarian Association pamphlet on pet food, A Commonsense Guide to Feeding Your Dog or Cat:
”Why Are Homemade Diets Not Recommended? Homemade diets are not recommended because there is a good chance that all the necessary nutrients or the proper proportions will not be provided. Incorrect preparation and cooking may also deplete certain nutrients and result in a deficient diet. As well, homemade diets are usually more expensive to produce, without providing better nutrition.”
There are a few "No's" when it comes to selecting ingredients for home cooking. Veterinary Surgeons would tend to advise against the following foodstuffs, or at least to be wary of feeding large quantities:
Mushrooms: best avoided as some dogs will not tolerate mushrooms well and they can cause serious toxicity.
Chocolate: Chocolate contains theobromine. Theobromine is a similar compound to caffeine and stimulates the heart and nervous system. In dogs it can poison them with death occurring from heart failure. Cats may not metabolise chocolate in the same way as dogs but are also thought to be at risk.
Onions (and garlic) OK in small quantities, but be careful. Can cause blood problems including anaemia.
Cows milk: Cats and dogs along with most other mammals lose, to a variable extent, their ability to digest lactose (milk sugar) with age, because the activity of the enzyme lactase declines with age
Macadamia nuts: The toxic compound is unknown but the affect of macadamia nuts is to cause locomotory difficulties. Dogs develop a tremor of the skeletal muscles, and weakness or paralysis of the hindquarters. Affected dogs are often unable to rise and are distressed, usually panting. Some affected dogs have swollen limbs and show pain when the limbs are manipulated.
Tomatoes: a small amount of ripe tomato is unlikely to cause any problems, but green tomatoes can cause stomach upsets so it’s best to avoid them.
Grapes: The ASCPA (Animal Poison Control Centre in the USA) has recently published information stating the toxicity of raisins and grapes in dogs (they do not know how they affect cats yet, but advise to avoid feeding them anyway). Eating just a handful of raisins and grapes has been shown to cause kidney failure.
Fatty foods: Very fatty foods may lead to problems such as pancreatitis. The pancreas releases enzymes to help digest the food. Pancreatitis is a very painful inflammatory condition associated with the ingestion of fatty foods.
Other odds and ends around the house that your pet might eat and have problems with might be
Pear pips, the kernels of plums, peaches and apricots, apple core pips (contain cyanogenic glycosides)
Potato peelings and green looking potatoes
Coffee grounds, beans & tea (caffeine)
Hops (used in home brewing)
Vegetables - Green vegetables are a great way of boosting your dogs immune system, you can feed these raw or cooked. Raw carrot makes a healthy treat. Vegetables are possibly better for dogs than fruit. Potato must be cooked, and mashed potato is a suitable ingredient for home cooking.
Fruit – in the wild, dogs would have scavenged windfall fruit as well as digesting the remains of fruit eaten by other animals when they pick over the carcass, so giving your dog fruit is not as strange as it might sound. Fresh fruit is packed full of anti-oxidants, vitamins and all sorts of other healthy nutrients, so it’s great for keeping your dog in top condition. Some fruits are quite acidic (as well as sugary) and may not be good for dogs with skin or digestive complaints.
Grains - Rice is universally recommended, and brown rice preferred, but make sure that it is well cooked so that your pet can get the maximum goodness.
Meat and fish - Vary the protein that you are feeding, so that a good range of amino acids is provided. Fish, particularly oily varieties are a good source of omega 3 and 6 oils.
Yoghurt – this is a great source of protein, calcium and vitamins, and is particularly good for dogs with diarrhoea thanks to the probiotics it contains.
Cottage cheese – another surprisingly healthy dairy food which is great for growing puppies and lactating bitches.
Brewer’s yeast - Can be purchased from health food stores or chemists as a food supplement and is full of nutrients and vitamins. You only need to use about 1/2 tsp a day with recipes.
Really, it's up to you and the ingredients that you have to hand, but a good guide to follow would be that given by Veterinary Surgeon John Burns of Burns Pet Nutrition who advises the following proportions of a home made diet for dogs
1/3 rd by volume boiled brown rice
1/3 rd by volume meat (this should be varied regularly using chicken, fish, lamb, beef)
1/3 rd by volume vegetable, again varied using roots and greens and to include some seaweed (dried or fresh)
John Burns adds 'I have less experience in the use of home made food for cats but in general cats need a higher level of protein and less carbohydrate.
'This could be achieved by increasing the meat portion to 50% with the rice and vegetable portions of 25% each. Again, some seaweed should be included to provide trace minerals.'
Cats have a very specific requirement for meat, and can’t survive without several essential amino-acids found only in meat. So a vegetarian diet for a cat is really not on. Also limit the amount of liver you feed your cat (to avoid an excess of Vit A) and make sure to cook fish (regular feeding of raw fish can apparently lead to a vitamin B deficiency)