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Thanks very much for requesting me to answer your question. It will be my pleasure to help you and Kira today.
I'm sorry to hear she has been having loose stools and throwing up frequently. This is probably due to the change in food, which was not made gradually; however, it would be a good idea to have her checked out by her vet as soon as possible, and bring a fresh fecal sample for analysis. Loose stools can have various causes, like intestinal parasites, food allergies, bacterial or viral intestinal infections, and the vet will be able to make a better diagnosis after an in-person visit and some lab work.
The Purina One food you bought may contain various allergens, if it has meat by-products, corn, soy, wheat, gluten, dairy products, artificial flavors, colors and/or preservatives. You want to find a food that has real meat or fish as it's first ingredients, no artificial ingredients and grain-free food is considered healthier. Also, canned food, as opposed to dry is also considered closer to a cat's natural diet (if she lived in the wild). You can read additional information written in these articles by a veterinarian, about the best way to feed our cats. http://catinfo.org/
If she is constantly licking at her bum, so much so that it has become raw, she may be uncomfortable with an irritation there from the runny stools, or she could have an anal gland problem which must be diagnosed and treated by the vet. The anal glands are located under the skin on either side of the anus. They contain fluid which is released with every bowel movement, however, if the fluid is not released because it is impacted, it could also be infected, and the vet will need to 'express' or empty her anal glands manually and treat any infection, if found. The sore she made on her bottom will also be evaluated and antibiotics will be given if needed, to help or prevent any infection.
For the moment, you can feed her some bland food like plain boiled chicken breast mixed with plain white rice--no salt/no seasonings. You can also offer her some plain, jarred baby food meat containing absolutely no seasonings (no
onion, garlic, etc.). Beechnut Stage 1 chicken and chicken broth is a good one, if they sell it in your area. If not, check the labels on other brands of pureed baby food meats to make sure they only contain meat and sometimes, water, for processing. You might also try giving her 1/4 of a regular strength (10mg) Pepcid AC tablet daily to help lower acid in her stomach and help with the vomiting. Excess acid causes nausea. Keep her on the bland diet until she sees the vet, and try to get her in as soon as possible, so all her symptoms can be diagnosed and treated, if necessary.
I hope all will be well with your Kira!
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