NAVLE PRACTICE QUESTIONS

Which of the following is the most common cause of maxillary sinusitis in the horse?

A. Bacterial lower respiratory tract disease extending into the sinus

B. Infection and abscessation of a tooth root extending into the sinus

C. Inhaled foreign bodies lodging in the sinus

D. Puncture wounds extending into the maxillary sinus

An African gray parrot that is presented for necropsy is suspected to have psittacosis. Which of the following findings is most likely to confirm the diagnosis?

(A) Hepatomegaly and splenomegaly on gross examination

(B) Identification of the causative organism by Gram's stain

(C) Isolation and identification of Chlamydia psittaci

(D) Presence of acid-fast organisms in the liver

A 5-year-old Holstein cow is being evaluated because of inappetence. On auscultation, there is pinging over the left ninth and 10th intercostal spaces, on a line between the tuber coxae and the elbow. On paracentesis immediately ventral to the pinging area, there are a few drops of green fluid with a pH of 6.0. Which of the following is the most likely source of the fluid?

A) Abomasum

(B) Cecum

(C) Omasum

(D) Rumen

(E) Spiral colon

A 3-month-old puppy is being evaluated because of weight loss, chronic diarrhea, and steatorrhea. Direct microscopic examination of saline smears of the extremely watery feces shows motile piriform trophozoites. Which of the following is the most appropriate pharmacotherapy?

(A) Dichlorvos

(B) Ivermectin

(C) Metronidazole

(D) Praziquantel

(E) Trimethoprim-sulfonamide

Infection of pregnant cows with bovine viral diarrhea virus may cause which of the following neurologic abnormalities in the newborn calf?

(A) Anencephaly

(B) Cerebellar hypoplasia

(C) Hydranencephaly

(D) Hydrocephalus

(E) Syringomyelia

A 9-year-old male Boston Terrier dog is found to have a 5-cm mass in the left inguinal area lateral to the prepuce. Cytologic examination of a fine-needle aspirate shows numerous round, discrete cells with reddish purple granules. The left inguinal lymph node is also enlarged. Similar cells are seen in the lymph node and in a blood smear. Which of the following is the most appropriate management?

(A) Administration of cisplatin and aluminum hydroxide

(B) Administration of levamisole and aspirin

(C) Administration of prednisone and cimetidine

(D) Conventional surgical removal of the mass

(E) Cryosurgical removal of the mass

An acute outbreak of vomiting and diarrhea in a litter of 1-week-old piglets is characterized by a high morbidity and a high mortality rate. Which of the following is the most likely cause?

(A) Clostridium perfringens type C infection

(B) Colibacillosis

(C) Rotavirus infection

(D) Transmissible gastroenteritis

(E) Vomiting and wasting disease

Which of the following abnormal cardiac rhythms is most frequently seen in dogs with gastric dilatation-volvulus?

(A) Atrial premature complexes

(B) Junctional escape beats

(C) Second-degree atrioventricular block

(D) Sinus bradycardia

(E) Ventricular premature complexes

A goat has a sudden onset of clinical signs of blindness, depression, head pressing, and anorexia that progress to recumbency with opisthotonos and nystagmus. Which of the following is the most likely diagnosis?

(A) Bacterial meningitis

(B) Caprine arthritis-encephalitis

(C) Listeriosis

(D) Polioencephalomalacia

(E) Scrapie

A 3-year-old gelding is being evaluated because of mild distress and food reflux from both nostrils. Rectal temperature is 100.2 F (37.9 C), pulse rate is 42/min, and respiratory rate is 12 breaths/min. Gastrointestinal borborygmi are present on examination. Which of the following is the most likely diagnosis?

(A) Cleft palate

(B) Esophageal obstruction

(C) Retropharyngeal abscess

(D) Ruptured stomach

(E) Small intestinal volvulus

A 2-year-old cat has a two-day history of anorexia and vomiting. Abdominal radiographs show that the intestines appear bunched up in accordionlike pleats. Which of the following is the most likely cause?

(A) Intestinal adenocarcinoma

(B) Intestinal lymphosarcoma

(C) Intestinal parasites

(D) Intussusception

(E) A string foreign body

Which of the following is the most appropriate therapy for swine dysentery?

(A) Lincomycin

(B) Penicillin

(C) Sulfathiazole

(D) Tetracycline

(E) Tilmicosin

A 4-year-old intact female Maltese dog has anorexia, fever, severe trembling, and stiffness of the limbs three weeks post partum. Which of the following is the most appropriate emergency therapy?

(A) Intramuscular calcium chloride

(B) Intravenous calcium gluconate

(C) Intravenous dexamethasone

(D) Intravenous 50% glucose

(E) Oral calcium lactate

A foal is weak and lethargic 48 hours after birth. The foal was normal at birth and began suckling vigorously at 1 hour of age. The dam's last two foals died at 3 and 4 days of age, respectively. Examination show icteric mucous membranes. Laboratory studies show hemoglobinuria. Which of the following is the most likely diagnosis?

(A) Acute hepatic necrosis

(B) Equine infectious anemia

(C) Equine viral arteritis

(D) Iron deficiency anemia

(E) Neonatal isoerythrolysis

A 5-year-old Quarter horse stallion collapses suddenly and lies covered with sweat in lateral recumbency. When the horse attempts to stand, it exhibits generalized muscle fasciculations, prolapse of the third eyelid, inspiratory stridor, and loose feces. The episode lasts for 25 minutes and then resolves without treatment. The horse appears normal 15 minutes thereafter. Which of the following is the most important question to ask the owner?

(A) Does the horse have a history of laminitis?

(B) Has the horse been receiving calcium supplementation?

(C) Has the barn had a recent outbreak of respiratory disease?

(D) What is the bloodline of the horse?

(E) What is the vaccination history of the horse?

A 10-year-old spayed female cat is being evaluated because of weight loss, polyphagia, polyuria, polydipsia, and restlessness. Cardiac arrhythmias are noted on auscultation. Which of the following is the most likely diagnosis?

(A) Chronic pancreatic insufficiency

(B) Chronic renal disease

(C) Congestive cardiomyopathy

(D) Diabetes mellitus

(E) Hyperthyroidism

A 4-month-old male Labrador Retriever has had watery diarrhea and vomiting for the past two days. The puppy is anorectic. On abdominal palpation, there is a cylindrical mass in the midabdomen. Radiographs show a midabdominal mass and many dilated loops of bowel. Which of the following is the most appropriate next diagnostic test?

(A) Barium enema

(B) Laparoscopy

(C) Laparotomy

(D) Pneumocolon

(E) Upper gastrointestinal series

Which of the following subpopulations is at greatest risk for developing clinical toxocariasis?

(A) Children with a history of pica

(B) Dog trainers

(C) Persons whose occupations require working under houses

(D) Persons with a recent history of swimming in farm ponds

(E) Slaughterhouse workers

A large commercial layer flock in southern California experiences a sudden increase in mortality and an abrupt decrease in egg production. The affected birds are cyanotic and have dyspnea and violent diarrhea. A few of the birds have conjunctivitis or pronounced nervous signs. Postmortem examination of sample birds shows marked tracheitis, acute airsacculitis, serosal hemorrhages, and prominent hemorrhages along the gastrointestinal tract, primarily involving lymphoid tissue. Which of the following is the most appropriate next step?

(A) Inform the owner that the outbreak will subside spontaneously

(B) Prepare to vaccinate other flocks in the immediate area for infectious laryngotracheitis

(C) Report the disease outbreak to the state/provincial veterinarian immediately

(D) Treat the birds with a broad-spectrum antibiotic in the drinking water

(E) Withdraw feed immediately and replace with new feed

Which of the following agents produces methemoglobinemia and Heinz body anemia in cats?

(A) Acetaminophen

(B) Aspirin

(C) Calcium ethylenediaminetetraacetic acid (EDTA)

(D) Ethylene glycol

(E) Lead

An adult female mixed-breed dog was recently found and is in poor body condition. Examination shows a distended abdomen. A radiograph of the abdomen is shown. These findings are most consistent with which of the following?



(A) Ascites

(B) Gastric dilation

(C) Gastrointestinal foreign body

(D) Hepatomegaly

(E) Pregnancy

Which of the following parasites is most likely to be a source of prenatally acquired infection in pups?

(A) Ancylostoma caninum

(B) Strongyloides stercoralis

(C) Toxocara canis

(D) Trichuris vulpis

(E) Uncinaria stenocephala

In a cow at 35 days' gestation, elective abortion is most likely to succeed with administration of which of the following?

(A) Dexamethasone

(B) Isoxsuprine hydrochloride

(C) Oxytocin

(D) Progesterone

(E) Prostaglandin F2alpha

A 5-month-old boar that is fast-growing and heavily muscled is being evaluated because of progressive bilateral lameness of the front legs. None of the other animals on the farm is affected. Which of the following is the most likely cause of this condition?

(A) Biotin deficiency

(B) Osteochondrosis

(C) Porcine stress syndrome

(D) Rickets

(E) Wobbler syndrome

A 10-week-old female German Shepherd dog is being evaluated because of chronic tearing of the left eye. Examination shows an island of hair growing in the temporal portion of the left cornea, extending from the conjunctiva. The anterior segment is clear, with no apparent abnormalities. Which of the following is the most likely diagnosis?

(A) Dermoid

(B) Ectopic cilia

(C) Pannus

(D) Pigmentary keratitis

(E) Trichiasis

A 3-month-old Appaloosa foal is being evaluated because of pyrexia, cough, and nasal discharge. The foal and its mother are housed in a dry lot with three other mares and their foals. Clinical examination of the foal shows increased respiratory rate and increased bronchovesicular sounds. Laboratory studies show leukocytosis with neutrophilia. Radiographs show a prominent alveolar pattern characterized by ill-defined regional consolidation. The most likely cause of these signs is infection with which of the following?

(A) Equine influenza virus

(B) Equine rhinopneumonitis virus

(C) Parascaris equorum

(D) Pneumocystis carinii

(E) Rhodococcus equi

An 8-week-old male Schnauzer dog has had episodes of vomiting or regurgitation for the past four weeks. A radiograph of the thorax is shown. These findings are most consistent with which of the following?



(A) Dietary indiscretion

(B) Gastric foreign body

(C) Gastrointestinal parasitism

(D) Megaesophagus

(E) Parvovirus infection

An otherwise healthy 9-year-old male Terrier dog with constipation is found to have a symmetrically enlarged prostate gland. On physical examination, palpation of the prostate gland does not produce pain; it is twice the normal size and movable within the pelvic canal. Which of the following is the most likely diagnosis?

(A) Acute prostatitis

(B) Benign prostatic hyperplasia

(C) Prostatic abscess

(D) Prostatic adenocarcinoma

(E) Prostatic cyst

Which of the following is the most appropriate site on the horse shown for administration of an intramuscular injection?



(A) A

(B) B

(C) C

(D) D

(E) E

A 2-year-old intact male domestic shorthaired cat is being evaluated because of lethargy. The cat has a fever. Laboratory studies show anemia. Microscopic examination of stained blood films shows dark-staining, round- to rod-shaped, nonrefractile bodies on the surfaces of numerous red blood cells. Which of the following is the most appropriate therapy?

(A) Doxycycline

(B) Griseofulvin

(C) Penicillin

(D) Trimethoprim-sulfonamide

(E) Vincristine

A 14-year-old Poodle is being evaluated because of polyuria and polydipsia. Physical examination of the dog shows symmetric alopecia, comedones, and a pot-bellied appearance. Hepatomegaly is also noted on examination. Which of the following tests is most appropriate to confirm the presumptive diagnosis?

(A) Determination of serum calcium concentration

(B) Determination of serum glucose concentration

(C) Determination of serum thyroxine (T4) concentration

(D) Low-dose dexamethasone suppression test

(E) Water deprivation test

A 6-month-old kitten is being evaluated because of intense scratching around the ears and frequent shaking of the head. Examination shows bilateral, circumaural, cutaneous excoriations and thick reddish brown crusts in the external ear canals. Which of the following is the most appropriate diagnostic test?

(A) Bacterial culture of aural exudate

(B) Fungal culture of aural exudate

(C) Microscopic examination of aural exudate

(D) Microscopic examination of deep scrapings of cutaneous lesions

(E) Wood's light examination

A 5-year-old dog is found to have isosthenuria and moderate azotemia. Which of the following concomitant findings is the most reliable indicator that the dog has chronic renal failure?

(A) Hyperkalemia

(B) Hyperphosphatemia

(C) Hypocalcemia

(D) Hypoglycemia

(E) Nonregenerative anemia

A 6-year-old neutered male cat was treated for a urethral obstruction three days ago but continues to have a full bladder that can be easily expressed. Which of the following drugs is most likely to help treat this cat's problem?

(A) Bethanechol

(B) Ephedrine

(C) Phenoxybenzamine

(D) Phenylpropanolamine

(E) Propantheline

A horse is being reevaluated six days after initial treatment of a minor corneal lesion. Reexamination of the affected eye shows photophobia, lacrimation, blepharospasm, corneal edema, and a yellowish white stromal infiltrate in the cornea. Vital dye does not stain the cornea. Which of the following is the most likely diagnosis?

(A) Corneal scar

(B) Corneal stromal abscess

(C) Deep corneal ulceration

(D) Primary lipid keratopathy

(E) Superficial corneal ulceration

A 6-month-old kitten has several rapidly expanding circular patches of alopecia. The owner's daughter has developed a lesion on her hand. Wood's light examination shows no fluorescence. Which of the following is the most appropriate next diagnostic test to perform on the kitten?

(A) Bacterial culture of hair from the lesions

(B) Fungal culture of hair from the lesions

(C) Fungal serology

(D) Histopathologic and cytologic examination of biopsy specimens of the lesions

(E) Microscopic examination of deep skin scrapings from the lesions

An iguana is reluctant to move and refuses to eat anything except lettuce and an occasional mealworm. Radiographs show multiple fractures and thin cortices in the bones. Which of the following is the most likely cause of the fractures?

(A) Hyperparathyroidism

(B) Hypervitaminosis D

(C) Iodine deficiency

(D) Vitamin A deficiency

(E) Vitamin E deficiency

A mature lactating dairy cow is being examined because of a sudden onset of anorexia, decreased milk production, decreased fecal production, and colic. On physical examination, the cow is dehydrated and alkalotic. There is an area of tympany, 15 cm in diameter, centered over the middle of the right 12th rib. On rectal examination, there is a tense structure in the right abdomen. Which of the following is the most likely diagnosis?

(A) Cecal volvulus

(B) Left abomasal displacement

(C) Pneumoperitoneum due to a perforated abomasal ulcer

(D) Right abomasal displacement without volvulus

(E) Right abomasal volvulus

A peach-faced lovebird is bleeding profusely from a broken primary feather. Which of the following is the best means to stop the hemorrhage?

(A) Apply ferrous sulfate powder

(B) Cauterize the feather with a silver nitrate stick

(C) Cut off the feather at skin level and cauterize the cut with electrocautery

(D) Pull out the broken feather and apply hemostasis to the follicle

(E) Do nothing; the bleeding will gradually stop

A 3-week-old calf dies after a 10-day history of fever and bloody diarrhea. Which of the following tests is most likely to confirm a diagnosis of salmonellosis?

(A) Culture of the mesenteric lymph nodes

(B) Fecal enzyme-linked immunosorbent assay (ELISA)

(C) Fecal flotation

(D) Fluorescent antibody testing of intestinal mucosa

(E) Hepatic histopathologic analysis

A 6-month-old kitten is being evaluated because of abnormal curvature of the legs. Radiographs of the skeleton show multiple healing fractures and generalized osteopenia. Which of the following is the most likely cause?

(A) Disuse osteopenia

(B) Nutritional secondary hyperparathyroidism

(C) Rickets

(D) Scurvy

(E) Toxic osteopenia

A 5-year-old cat is being evaluated because of a sudden onset of paralysis of the rear legs. Femoral pulses are absent, and the rear legs are cold and painful. Spinal reflexes of the rear legs are absent. Which of the following is the most likely diagnosis?

(A) Aberrant parasitic migration

(B) Aortic thromboembolism

(C) Fibrocartilaginous emboli

(D) Intervertebral disk herniation

(E) Trauma to the spinal cord

Which of the following is the preferred site for intravenous injection in mature swine?

(A) Anterior cephalic vein

(B) Dorsal auricular vein

(C) Femoral vein

(D) Jugular vein

(E) Lateral thoracic vein

Which of the following is the most likely cause of dilated cardiomyopathy in an adult cat?

(A) Hyperthyroidism

(B) Neoplasia

(C) Pulmonary fibrosis

(D) Taurine deficiency

(E) Toxoplasmosis

A 100-cow dairy herd is being evaluated because of a 10% average decrease in daily milk production, a 60% incidence of loose stools, and a high incidence of reddened coronary bands and rear-leg shifting lameness. Two milking cows have died of unknown causes in the past two weeks. Which of the following is the most likely diagnosis?

(A) Bovine virus diarrhea

(B) Dietary protein deficiency with associated decrease in milk production

(C) Hairy heel warts

(D) Laminitis secondary to ruminal acidosis

(E) Salmonellosis

A 2-year-old Quarter horse is being evaluated because of pyrexia, anorexia, and depression. Clinical examination shows a bilateral nasal discharge and retropharyngeal swelling. Which of the following is the most likely diagnosis?

(A) Esophageal obstruction

(B) Equine influenza

(C) Equine viral rhinopneumonitis

(D) Guttural pouch mycosis

(E) Strangles

One hour after being vaccinated, a puppy develops sudden swelling and pruritus of the lips, eyelids, and nose. Which of the following is the most likely cause of these signs?

(A) Arthus reaction

(B) Cell-mediated hypersensitivity

(C) Cytotoxic hypersensitivity

(D) Immediate hypersensitivity

(E) Immune-complex-mediated hypersensitivity

A 5-year-old male Old English Sheepdog is being evaluated because of collapse. A lead II electrocardiogram (sensitivity, 1 mV = 1 cm) is shown. These findings are most consistent with which of the following?



(A) Cardiomyopathy

(B) Endocarditis

(C) Mitral regurgitation

(D) Pericardial effusion

(E) Subaortic stenosis

Which of the following is the most likely cause of hemorrhagic enteritis affecting the small intestines of suckling pigs?

(A) Clostridium perfringens type C

(B) Isospora suis

(C) Rotavirus

(D) Salmonella choleraesuis

(E) Serpulina hyodysenteriae

Which of the following is the most likely cause of generalized polymyopathy secondary to chronic renal failure in cats?

(A) Hypochloridemia

(B) Hypokalemia

(C) Hypomagnesemia

(D) Hyponatremia

(E) Hypophosphatemia

A group of 2-week-old dairy calves develop watery diarrhea that is unresponsive to antibiotic therapy. A fecal sample contains round 2- to 4-cm bodies that are acid-fast-positive. Which of the following is the most likely causative organism?

(A) Cryptosporidium spp

(B) Escherichia coli O157:H7

(C) Mycobacterium spp

(D) Nocardia spp

(E) Salmonella spp

fter the initial estrous cycle, a 6-month-old cat has firm enlargement of all mammary glands. Mammary gland hyperplasia is suspected. Which of the following is the most appropriate management?

(A) Bilateral radical mastectomy

(B) Estradiol cypionate therapy

(C) Furosemide therapy

(D) Megestrol acetate therapy

(E) Ovariohysterectomy

An adult female rabbit has a sudden onset of paralysis of the hindquarters and urinary incontinence. Which of the following is the most likely diagnosis?

(A) Idiopathic demyelination

(B) Metastatic uterine adenocarcinoma

(C) Mycotoxicosis

(D) Saddle thrombus

(E) Spinal injury from inappropriate handling

A 550-lb (249.2-kg) steer is standing alone and shifting its weight from one rear leg to the other. Physical examination shows spasms in the perineal area. Which of the following is the most appropriate diagnostic test?

(A) Analysis of fibrinogen

(B) Blood urea nitrogen (BUN) concentration

(C) Insertion of a urinary catheter

(D) Leukogram

(E) Rectal palpation

Removal of a midjejunal foreign body from a cat requires partial intestinal resection. Which of the following anastomotic techniques is most likely to provide both secure closure and the largest luminal diameter?

(A) Double-layer appositional

(B) Double-layer everting

(C) Double-layer inverting

(D) Single-layer appositional

(E) Single-layer inverting

An otherwise healthy 8-year-old Great Dane dog has become acutely lame. Radiographs of the affected limb show lysis in the distal radial metaphysis. Which of the following is the most likely diagnosis?

(A) Bacterial osteomyelitis

(B) Eosinophilic panosteitis

(C) Hypertrophic osteodystrophy

(D) Osteochondrosis

(E) Osteosarcoma

On physical examination, a 12-year-old male dog is found to have bilaterally symmetric alopecia, enlarged mammary glands, and a pendulous prepuce. Which of the following is the most likely cause of these findings?

(A) Adrenocortical adenoma

(B) Anal sac adenocarcinoma

(C) Pituitary adenoma of the pars distalis

(D) Prostatic adenocarcinoma

(E) Testicular Sertoli cell tumor

A 3-year-old Thoroughbred racehorse has a history of tiring early in a race and making a high-pitched noise when inspiring while running. Which of the following diagnostic tests is most likely to determine the cause?

(A) Cytologic examination of a transtracheal wash

(B) Endoscopy of the larynx

(C) Radiographs of the guttural pouches

(D) Radiographs of the thorax

(E) Sinus centesis

A 6-year-old neutered male cat is being evaluated because of lethargy and depression. On cardiac examination, a grade III/VI murmur and a gallop rhythm are detected. Heart size appears normal on a radiograph. Which of the following tests will provide the most accurate cardiac anatomic information?

(A) Aortic angiography

(B) Echocardiography

(C) Electrocardiography

(D) Pericardiography

(E) Pulmonary angiography

A 7-year-old mare has had intermittent signs of moderately severe colic for the past 48 hours. Heart rate is 56 beats/min. Hydration, acid-base balance, and electrolyte parameters are near normal. On rectal examination, the left dorsal and ventral colon feels distended and is felt coursing in a dorsocranial direction. The spleen is displaced caudomedially. Which of the following is the most likely diagnosis?

(A) Cecocolic intussusception or cecal inversion

(B) Displacement of the left colon over the nephrosplenic ligament

(C) Ileocecal intussusception

(D) Infarction of the large colon

(E) Volvulus of the large colon and the cecum

This parasite ova was found on fecal flotation of a 5-year-old dog with a history of intermittent bloody diarrhea. Which of the following is the most appropriate labeled pharmacotherapy?



(A) Pyrantel

(B) Ivermectin

(C) Metronidazole

(D) Trimethropim-sulfa

(E) Fenbendazole

This parasite ova was found on fecal flotation of a 5-year-old dog with a history of intermittent bloody diarrhea. Which of the following is the most appropriate labeled pharmacotherapy?



(A) Pyrantel

(B) Ivermectin

(C) Metronidazole

(D) Trimethropim-sulfa

(E) Fenbendazole

A 5-year-old gelding presents with ataxia and incoordination in all four limbs. A CSF tap reveals antibodies to Sarcocystis neurona. How did the horse most likely acquire this infection? 

(A) Transmission of sporozoites via the bite of a tabanid fly 

(B) Ingestion of oocysts from the feces of an infected horse 

(C) Ingestion of sarcocysts in the muscle tissue of an infected opossum 

(D) Transmission of sporozoites via tick bite 

(E) Ingestion of sporocysts from opossum feces in contaminated feed or water

This parasite was detected on fecal flotation of a 3-month-old puppy with acute diarrhea. Although many dogs will self-cure this parasite, you decide to prescribe a treatment. What treatment is most appropriate?



(A) Sulfadimethoxine 

(B) Fenbendazole 

(C) Ivermectin 

(D) Metronidazole 

(E) Pyrantel

Define pharmacokinetics