Dog with crystals in urine

Question
My dog is an 8 year old female of no specific breed (she came from a shelter).  She is 45-50lb.  She was recently treated for a bladder infection. The follow-up urinalysis showed high pH (i think 8.5) and struvite crystals.  The vet wants to put her on Royal Canin S/O but it is so expensive.  I am interested in other alternatives, especially now that I've researched the product and found that it might not contain the best ingredients.  

Also, she recently started losing tufts of hair and is fairly itchy, but no sign of fleas.  Could this all be related to a food allergy?  She usually eats Science Diet Senior and has eaten Science Diet ever since she was a puppy.  I look forward to your response.

Answer
Hi Michele - Well, the Science Diet is loaded with fillers and is an average food.  The Royal Canin is a little better and the S/O has been known to help a bunch!
I can direct you to some friends that make special home-cooked diets for pets.  This group is on Yahoo....
If you want to work at cooking, that would be your only other option besides the Royal Canin.

As far as the fur falling off- could be all the fillers in the food.  In time, the grains and corns can make the skin dry and the coat very brittle.  

NuVET wafers are a great skin and coat supplement....
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