You need Bloodwork on this dog and those crystals need to be looked at under a microscope.
Take him to the Vet immediately Bladder Stones | Dog Health Problems | Diseases, Illnesses & Symptoms | FetchDog
In short...
Signs of a bladder stone can include:
vocalizing during urination
painful urination
bloody urine
frequent attempts to urinate
straining to urinate
dribbling when urinating
lethargy
appetite loss
inability to urinate.
These last three signs may indicate a bladder stone is completely obstructing urine flow.
This condition is life-threatening, so take your dog to the veterinarian immediately.
Your veterinarian will perform a complete physical examination and may use blood tests, X-rays, ultrasound, urinalysis, bacterial culture and sensitivity testing, and stone analysis to diagnose the presence and type of bladder stone, as well as any underlying metabolic disease. If your dog passes a stone while urinating, save it. Your veterinarian will have its mineral content analyzed before choosing a treatment.
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