Blood Urea Nitrogen (BUN) in rabbits

MediRabbit.com is funded solely by the generosity of donors. Every donation, no matter what the size, is appreciated and will aid in the continuing research of medical care and health of rabbits. Thank you

Urea is a nitrogenous waste product formed during the protein degradation process in the liver. It circulates in the blood in the form of urea nitrogen and is transported to the kidneys, where it is filtered and excreted. In healthy, well-hydrated rabbits, the majority of urea nitrogen is filtered and excreted with the urine. The presence of urea nitrogen in the blood can be measured using the blood urea nitrogen (BUN) test.

Reference level in a healthy rabbit: 13-30 mg/dl.

Unlike other animals, the level of BUN in rabbits can be easily influenced by physiological or environmental factors. It may be influenced by the rabbit's stress levels at that particular moment, which can be affected by factors such as hydration status, transportation, unfamiliar individuals or environments, unusual odors, and barking dogs. Other factors that can affect the test result: diet, the time of day the sample is taken (higher levels of BUN are observed in the late evening), and medication (e.g., chloramphenicol, streptomycin, gentamicin, tobramycin, diuretics, and corticosteroids). Additional factors that can impact the BUN level, including the presence of parasites like coccidiosis or bacterial catabolism in the cecum. Bacterial catabolism is a process in which bacteria use nitrogen during metabolic breakdown reactions or during periods of food abundance.

If the BUN level is found to be elevated, it is advisable not to rapidly conclude that the rabbit is suffering from kidney failure, as is often the case for cats and dogs. A second sample should be taken once the rabbit is adequately hydrated (but not overhydrated) and compared with the previously obtained result.

Elevated BUN levels can be caused by:

· kidney failure;

· low volume of blood/plasma due to diarrhea (hypovolemia);

· blockage of the urinary tract by a kidney or a bladder stone, a tumor or a polyp;

· a heart disease;

· bleeding in the digestive tract;

· toxic insults.

Low BUN levels can be caused by:

· over-hydration;

· malnutrition;

· liver disease or damage;

· medication;

· gestation.

Medical imaging techniques such as X-rays and ultrasounds can be utilized to detect various renal abnormalities, including kidney enlargement, the presence of renal stones, malignant tumors, cysts, and fibrosis.

The following signs are indicative of kidney disease:

- Decreased appetite

- Weight loss

- Lethargy

- Anemia

- Increased urination

- Increased thirst.

e-mail: info@medirabbit.com