Canine Medicine and Surgery Flashcards

A 3-year-old intact female Cocker Spaniel is presented with a fever, mucopurulent vaginal discharge, PU/PD, and leukocytosis. Abdominal ultrasound confirms uterine distension. What is the definitive treatment?

Answer: Ovariohysterectomy

Ovariohysterectomy is the definitive and safest treatment for pyometra, removing the source of infection and preventing recurrence.

A dog presents with acute epistaxis, petechiae on the gums, and prolonged bleeding after venipuncture. CBC reveals a platelet count of 8,000/μL. Coagulation times (PT and aPTT) are normal. What is the most likely diagnosis?

Answer: Immune-mediated thrombocytopenia (IMT)

IMT presents with severely low platelets causing mucosal bleeding and petechiae while PT and aPTT remain normal because coagulation factor function is intact.

A 1-year-old male intact German Shepherd presents with bilateral cryptorchidism. The owner wants the dog neutered. Which statement is most accurate?

Answer: Both retained and descended testicles must be removed

Retained testicles have a 13-14 times higher risk of developing Sertoli cell tumors and testicular torsion, so both must be removed during neutering.

A 4-year-old Border Collie presents with episodic muscle tremors, hypersalivation, and mydriasis after being on a rural property. Organophosphate toxicosis is suspected. What is the mechanism and antidote?

Answer: Acetylcholinesterase inhibition; atropine and pralidoxime

Organophosphates irreversibly inhibit acetylcholinesterase causing acetylcholine accumulation; atropine blocks muscarinic effects while pralidoxime reactivates the enzyme if given early.

On thoracic auscultation of an 8-year-old Cavalier King Charles Spaniel, you hear a grade IV/VI left apical systolic heart murmur. Echocardiography shows myxomatous mitral valve disease with moderate left atrial enlargement (LA:Ao ratio 1.7). Which ACVIM staging is most appropriate?

Answer: Stage B2

Stage B2 MMVD is defined by cardiac remodeling (LA:Ao ≥1.6 or normalized left ventricular internal diameter in diastole >1.7) without clinical signs of heart failure.

A 6-month-old Labrador Retriever puppy presents for evaluation of exercise intolerance and a loud continuous 'machinery' murmur heard best at the left heart base. What is the most likely congenital defect?

Answer: Patent ductus arteriosus

Patent ductus arteriosus produces the classic continuous 'machinery' murmur due to left-to-right shunting throughout the cardiac cycle via the unclosed ductus.

A 5-year-old Siberian Husky is presented with zinc toxicosis after ingesting pennies minted after 1982. Which hematologic finding best explains the hemolysis observed?

Answer: Heinz body formation from oxidative RBC damage

Zinc causes oxidative damage to RBC membranes and hemoglobin, leading to Heinz body formation and intravascular hemolytic anemia.