First, it’s important to note that the timing of urine collection has little impact on test results. You may collect the sample in the morning or evening, before or after your pet’s meal. Ideally, the sample should be analyzed within 30–60 minutes. However, it may be refrigerated for 12–24 hours if needed. After 24 hours, artifacts can develop in the urine and potentially alter the results. If you’re unable to collect the sample yourself, don’t worry—other collection methods are available and described below.

• Free catch (natural voiding) is the only method you can perform yourself. For dogs, simply collect the urine in a clean, sealed container while taking them outside to urinate. For cats, you may replace the regular litter (after thoroughly cleaning the litter box) with non-absorbent litter beads available from your veterinarian. Because the beads do not absorb urine, the sample can then be transferred into a container.

Cystocentesis is a procedure performed by your veterinary technician or veterinarian. Using a syringe, a needle is gently inserted directly into the bladder through the abdominal wall. Ultrasound guidance is sometimes used to assist with the collection. Cystocentesis allows for a sterile sample that is not contaminated by passage through the lower urinary tract (urethra), making it the preferred method when a urine culture is required.

• Catheterization involves placing a catheter through your pet’s urethra into the bladder. Urine is then collected using a syringe attached to the catheter. Catheterization may irritate the urethra and can increase the risk of urinary tract infection by introducing bacteria from the urethra into the bladder.

The physical evaluation assesses the urine’s color and turbidity (whether it appears cloudy). Normal urine typically ranges from pale to dark yellow and is clear. Urine specific gravity is then measured using a refractometer.

Urine’s role is to eliminate certain waste products from the body. If an animal is dehydrated, the kidneys attempt to reabsorb as much water as possible from the urine to conserve fluids. Measuring urine specific gravity provides insight into how effectively this mechanism is functioning—specifically, whether the kidneys are concentrating waste appropriately without excessive water loss.

A high urine specific gravity (very concentrated urine) may indicate dehydration or an underlying medical condition. A low specific gravity (very dilute urine, containing excess water) may suggest the kidneys are not functioning properly. These findings must be carefully interpreted alongside the clinical examination and other diagnostic results (e.g., complete urinalysis, bloodwork).

During chemical analysis, a drop of urine is placed on each reagent pad of a test strip (Image 1). Each pad assesses a specific parameter. The strip provides information about urine pH, protein content, glucose levels, ketones, and the presence of blood. By comparing the color changes to a standardized reference scale, these components can be quantified.

For example, if a significant amount of protein is detected, it may indicate that the kidneys are allowing protein to pass into the urine—something that is not typical of normally functioning kidneys.

Before proceeding with this step, the urine sample is centrifuged to concentrate the solid components into a sediment pellet. After separating the liquid portion from the sediment, a drop of stain is added to the urinary sediment. This bluish mixture is then placed on a microscope slide.

Depending on the animal’s condition, components that are not normally present in urine may be observed (e.g., urinary crystals, bacteria, white blood cells, red blood cells, epithelial cells, casts, etc.). Because urine is typically sterile, the presence of cocci (round bacteria) or rods (elongated bacteria), especially alongside white blood cells (neutrophils), may indicate a urinary tract infection.

Under the microscope, the quantity of each observed component is generally graded on a scale from 0 to 4+.

A urine culture may be recommended based on the animal’s symptoms or findings from the urinalysis (such as the presence of bacteria). As the name suggests, this test allows abnormal bacteria present in the urine to grow in order to accurately identify the specific type and determine the most appropriate antibiotics to treat the infection.

As mentioned previously, to avoid culturing environmental contaminants (such as bacteria from the litter box or the external urethral opening), cystocentesis is the preferred collection method for this test. The sterile sample is then sent to an external reference laboratory for analysis.

These various urine tests help your veterinarian determine the source of your companion’s health issue and provide you with the necessary information regarding appropriate treatment options.