Nora, a 3-year old, 41.1-lb (18.7-kg) spayed border collie crossbreed, was presented on an emergency basis for respiratory distress and inappetence of 48 hours’ duration. The owner reported a cough that had developed and progressively worsened, as well as a decrease in appetite and activity, over the previous month. In the 48 hours prior to presentation, Nora had also become reluctant to go on her regular daily walks. The owner additionally reported loss of muscle mass and noted that, in the few days before presentation, Nora had seemed uncomfortable with an abdominal breathing component and that respiratory rate and effort had progressively increased.
Nora had been fed 3 cups of a grain-free dry kibble diet per day since adoption from a shelter 2.5 years previously. The diet’s main ingredients included kangaroo, kangaroo meal, chickpeas, peas, and lentils. Additional dietary history included occasional freeze-dried liver treats (maximum, 2-3 per week) from a local pet store and no human food. She was not receiving any vitamins, supplements, or medications other than her monthly parasite preventive. Nora was considered an otherwise healthy dog, had no travel history since adoption, and was up-to-date on flea, tick, and heartworm preventives.
On presentation, Nora was quiet but alert and responsive and had a BCS of 3/9 and mild muscle wasting. She was moderately dyspneic and tachypneic, with a resting respiratory rate of 60 breaths per minute. She had weak femoral pulses (200 bpm), was normothermic (100.3°F [37.9°C]), and had light pink mucous membranes, with a capillary refill time of 2 seconds. Jugular venous distension was observed. Cardiac auscultation revealed tachycardia with a regular rhythm and a grade II/VI left apical systolic heart murmur. Harsh bronchovesicular sounds and crackles were auscultated. Because of concern for congestive heart failure (CHF), furosemide (2 mg/kg IV) was administered, the patient was placed in an oxygen cage, and a cardiac consultation was conducted.