A 2-year-old male castrated golden retriever dog was presented for exercise intolerance, weight gain, and excessive shedding (22a). In addition, the owner reported the dog has ‘lost his obedience training’ and sleeps all of the time. Physical examination reveals an obese dog with a heart rate of 45 beats per minute. The dog’s face has a tragic expression. Large clumps of hair are easily epilated from the hair coat (22b).
i. What is the most likely cause of the dog’s clinical signs, and what diagnostic tests should be performed?
ii. If one single diagnostic test was available to perform in this patient what would it be, and how should it be interpreted?
iii. In this patient, basal T3 and T4 were unusually elevated. What is the most likely explanation?
