Question

A male dog is presented for a possible urinary infection, and the veterinarian would like you to collect a urine sample by cystocentesis. Where should the technician insert the needle for the collection?

a. Cranial to the umbilicus
b. Cranial to the sheath
c. Caudal to the umbilicus and to the side of the sheath
d. Caudal to the umbilicus

Answer 1

For a cystocentesis in a male dog, the needle is inserted caudal to the umbilicus to access the bladder's dome that projects into the abdomen when filled with urine.

Step-by-step explanation:

To collect a urine sample by cystocentesis from a male dog, the technician should insert the needle caudal to the umbilicus. This is because the bladder, which is the reservoir for urine, is located posterior to the pubic bone and anterior to the rectum in males. By inserting the needle caudal to the umbilicus, the technician is aiming for the bladder's dome, which projects into the abdomen when distended with urine, and thus avoids other abdominal structures.