Hello Penny:
I recently went through a similar experience and spent a year researching horse rescue and adoption. Facebook and forums proved invaluable for me. I learned many things from the experiences posters shared on-line. I was also fortunate because my Vet has experience with rescue horses and gave me expert guidance throughout the process. IMO you’re on the right track looking into this health condition prior to making any decisions about adoption!
I personally would never feed or recommend a homemade recipe that was not formulated by a credentialed veterinary nutritionist (ACVN or PhD in small animal nutrition) for my cat or dog. Many recipes I have seen posted are lacking essential vitamins and minerals. Feeding a diet, homemade or commercial, that is not balanced or feeding a commercial food far below recommended amounts over a long period might exacerbate any health issue(s) known or unknown. Ensuring they get all there required vitamins and minerals especially when they have a known health condition is important. There are many recipes on the Internet that bloggers and Vets have posted. Ask the formulators if they are credentialed in small animal nutrition, my guess would be no for most of them.
If a Vet has recommended a special diet or even if you’re just interested in feeding a balanced homemade diet I second C4C’s suggestion to check out BalanceIT.com or petdiets.com. I use a product from BalanceIT for my pup, he loves his homemade meals. The recipes are simple to make and there are many options for budget friendly ingredients.
It sounds like a good start since you have her medical history and she already had the stones removed. I hope an adoption works out for you both!!
Here’s a few sites you may find helpful:
https://www.vetmed.umn.edu/centers-programs/minnesota-urolith-center/recommendations
http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=460
Struvite info:
https://www.vetmed.umn.edu/sites/vetmed.umn.edu/files/canine_struvite_uroliths.pdf
petdiets.com provides a free “ask the Veterinary Nutritionist” service:
https://petdiets.com/Ask-the-Nutritionist
