Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
There are a handful of causes of urination that has blood in it or can cause the urine to become darker (brown can be muscle enzyme release, blood, bilirubin):
1.) A urinary tract infection
2.) Bladder stones that traumatize the bladder and cause bleeding
3.) A bladder tumor, most likely in a senior pet
4.) Trauma- hit by car, muscle trauma of some kind
5.) Liver or kidney changes
Ideally until you are able to get to your veterinarian, please increase water intake. You can do this by supplementing the dry food with water and flavoring the water (maple syrup for example) as well. Increasing the water intake will help "flush" out the bladder and reduce the pain associated with the bleeding but also if this is not overt blood can help reduce the workload of the kidneys and filtration system by flushing out the toxins the bladder is urinating out.
Collecting a first morning sample in a tupperware container and refrigerating the sample if more than an hour old to have your vet evaluate the sample will help determine the cause of the blood in the urine.
Your vet will run a urinalysis, potentially do a urine culture to look for bacteria, an X-ray to rule out a bladder stone, and bloodwork to ensure there is not a metabolic cause or kidney issues causing the symptoms
Diagnosing the issue will help determine how best to treat the blood in the urine to get your pet comfortable swiftly
Below is more information on this condition in dogs, called hematuria (blood in urine) but whether this is what is going on with Duce will be determined by the urinalysis:
If Duce begins to have lethargy, vomiting, straining to urinate with little to no production then this becomes more of an emergency.
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