I had to start my cats on homemade food....one sign of your pet having problems with store bought food, is frequent urination and there being spots of blood in it..yes and feline will go anywhere they feel comfortable...
I suggest that if your pet is having this problem that you visit your local vet and get a proper diagnoses..but come SHTF will they be available or to expensive for you to care for your beloved pet..
Why am I focusing on urinary problems,because I have had one of my male cats with this problem and now one of my female cats...( all of my pets are fixed)
What happened was I took an out of town trip and in my haste bought WalMart no name food for my cats, well after I started them on that, that is when all my problems started...and I have had these cats for almost a year now, so I am thinking that Walmart brand of foods is high on the PH level and that these 2 cats cannot handle it...I have 5 cats in total
So what are my furry babies on now...
Every few days I go check out the meat section at one of grocery stores here, they put mark downs on some of the meats, so I hunt through those..my fur baby cats, can get a variety of meats froma ll the way from liver to chicken, mixed with rice, a small of amount of dried powdered egg and a touch of powdered milk..and sometimes carrots..(because of the urinary problems I have added a bit of cranberry juice to their food)This is not necessary if you are just making them homemade foods to cut costs or for health reasons
Now cats are carnerverous and need more meats then a dog would and you run the chance when you make thier own food of depriving them of their B suppliments...so be very careful of this..even if you use canned tuna or salmon there is not enough B vitamin for your cats...
I am hoping to come across a cat suppliment of vitamin B for SHTF.....in the mean time they get a higher portion of meat in there food then rice..
As for your dog, well we have a dump bin everything from bread crusts to left over meats go into the container for him....I will also make him batches of food mivture of pasta, rice, meats and the leftovers.with the dog becuase he is 11 years old he gets a high quality dog food mixed with his homemades( I don't do this with cats because there are 5 of them and they go threw the good food to fast)
Now PLEASE remember cats and dogs CANNOT have onions or any kind of peppers...
I am grabbing the DO NOT list from a site I have just googled..please print this out for SHTF, so you will know what NOT to feed your pets if you have to make your own food for them...
Alcoholic Beverages: Any type of alcohol can be poisonous to your pet and aside from intoxication, can cause a coma or even death.
Apple Seeds: Can have varied effects on pets.
Apricot Pits: Can cause respiratory difficulties such as breathing, coughing and sneezing.
Cherry Pits: Can cause respiratory difficulties such as breathing, coughing and sneezing.
Candy containing the sweetener Xylitol: Can cause liver damage and even death.
Chocolate: Although pets should never have any type of

, milk

is not nearly as dangerous for animals as semi-sweet or unsweetened bakers

. Chocolate poisoning can cause irregular heart rate and rhythm, restlessness, hyperactivity, diarrhea, vomiting, panting, muscle tremors, abdominal pain, bloody urine, increased body temperature, seizures, coma and possibly even death.
Coffee: Can result in increased breathing and heart rate, restlessness and affects the central nervous system.
Grapes: Large amounts of grapes can be poisonous to pets and can cause vomiting, diarrhea, lethargy, abdominal pain, lack of appetite and kidney damage.
Hops: May cause panting, elevated temperature, increased heart rate, seizures and possibly death.
Macadamia Nuts: Can cause vomiting, lethargy, hyperthermia, abdominal pain, stiff joints, lameness and tremors.
Moldy Foods: Can have varied effects on pets including vomiting and diarrhea.
Mushrooms: Different types of mushrooms can have varied effects on pets such as, depression, diarrhea, nausea and vomiting, abdominal pain, tearing, hallucinations, defecation, liver failure, seizures, drooling, urination, kidney failure, heart damage, hyperactivity and in some cases, death.
Mustard Seeds: Can have varied effects on pets.
Onions and Onion Powder: Can cause gastrointestinal problems such as vomiting and diarrhea.
Peach Pits: Can cause respiratory difficulties such as breathing, coughing and sneezing.
Potato Leaves and Stems: Can cause problems with the digestive, nervous and urinary systems.
Raisins: Large amounts of raisins can be poisonous to pets and can cause vomiting, diarrhea, lethargy, abdominal pain, lack of appetite and kidney damage.
http://www.earthclinic.com/Pets/poisonous_foods.html