Free DACZM Practice Questions

Question 1

A 4-year-old Asian elephant is quieter than usual and eating less. Over 24 hours, EEHV DNA in EDTA whole blood rises from 300 to 3,000 viral genome equivalents/mL. The platelet count falls below the laboratory's reference interval, with no platelet clumping on the smear. The tongue remains pink, and no edema is present. How should these findings change management?

Accepted Answer

Begin EEHV-directed antiviral and supportive treatment with frequent blood monitoring.

Answer

Wait for tongue cyanosis or edema before starting EEHV treatment.

Answer

Require confirmation by trunk-wash PCR before starting antiviral treatment.

Answer

Repeat blood PCR tomorrow, withholding antivirals while the load remains below 5,000.

Question 2

Koi develop gill irritation after buffering raises their tank's pH from 7.4 to 8.4. Temperature remains 24°C, dissolved oxygen is adequate, and total ammonia nitrogen remains 2.0 mg/L as nitrogen. At this temperature, the un-ionized fraction is 1.31% at pH 7.4 and 11.71% at pH 8.4. The facility intervenes at 0.10 mg/L un-ionized ammonia-nitrogen (NH3-N). Compatible, conditioned, ammonia-free replacement water is available. Which current concentration and response are appropriate?

Accepted Answer

Approximately 0.23 mg/L NH3-N; begin partial water replacement to reduce exposure.

Answer

Approximately 0.026 mg/L NH3-N; observe without changing the water.

Answer

Approximately 0.23 mg/L NH3-N; add more buffer to accelerate nitrification before exchanging water.

Answer

Approximately 0.023 mg/L NH3-N; maintain the present system and repeat ammonia testing tomorrow.

Question 3

Aspergillus fumigatus grows from an air-sac lavage collected from a dyspneic Humboldt penguin. Endoscopy reveals pale plaques, but the clinician must distinguish invasive aspergillosis from recovery of an environmental organism. Which additional result would provide the strongest evidence of invasion?

Accepted Answer

Hyphae penetrating the air-sac wall within areas of necrosis and granulomatous inflammation.

Answer

Aspergillus antibodies detected in a serum sample collected before antifungal treatment.

Answer

The same fungal species recovered from a second independently collected air-sac lavage.

Answer

Air-sac wall thickening and discrete soft-tissue nodules on computed tomography.

Question 4

A neutered male ferret with truncal alopecia, renewed sexual behavior, and an enlarged adrenal gland improves after a deslorelin implant. Follow-up ultrasonography still shows the adrenal lesion. The clinical response despite persistence of the lesion is best explained by which drug effect?

Accepted Answer

Sustained GnRH stimulation causing pituitary receptor downregulation and reduced gonadotropin secretion.

Answer

Direct inhibition of adrenal steroid-synthetic enzymes, reducing hormone production.

Answer

Selective destruction of adrenal cortical cells, leaving a nonfunctional residual mass.

Answer

Competitive blockade of peripheral androgen receptors, preventing circulating steroids from exerting effects.

Question 5

Several hours after a prolonged capture, a blackbuck develops a stiff gait and dark red-brown urine. Creatine kinase activity is approximately 100 times the laboratory's upper reference limit; AST activity is also markedly increased. Fresh urine is strongly positive for heme but contains almost no erythrocytes. Plasma is clear, and packed cell volume is unchanged. What unifies the laboratory findings?

Accepted Answer

Rhabdomyolysis with myoglobinuria and release of AST from injured muscle.

Answer

Intravascular hemolysis with hemoglobinuria and hypoxic liver injury.

Answer

Primary liver injury with bilirubinuria and stress-related creatine kinase release.

Answer

Traumatic urinary tract hemorrhage with erythrocyte lysis and incidental muscle enzyme leakage.

Question 6

A bison dies with widespread vasculitis, and lesion testing identifies ovine herpesvirus 2. The collection also contains clinically healthy domestic sheep and wildebeest. After the affected bison is removed, management proposes changes to prevent another case. Which change targets the maintenance host of the virus identified?

Accepted Answer

Eliminate bison exposure to domestic sheep and their secretions, including exposure to healthy sheep.

Answer

Separate bison from wildebeest while retaining their exposure to domestic sheep.

Answer

House bison individually, without changing their contact with small ruminants.

Answer

Remove sheep with fever or nasal discharge while retaining contact with the normal sheep.

Question 7

An oxytocin order is being reviewed for an anorectic female green iguana. Serial ultrasonography shows persistent, enlarged follicles attached to both ovaries and empty oviducts. Hydration, calcium status, thermal conditions, and nesting access have been corrected without improvement. Why is oxytocin unlikely to resolve this particular lesion?

Accepted Answer

Oviductal contractions cannot expel follicles that have not ovulated from the ovaries.

Answer

Oviductal eggs must develop mineralized shells before oxytocin can stimulate their passage.

Answer

The enlarged reproductive structures indicate an obstructed pelvic outlet requiring surgical enlargement.

Answer

The ultrasound pattern represents normal gravidity, making anorexia a physiologic rather than pathologic finding.

Question 8

Translocation screening of an apparently healthy endangered antelope yields a positive result. In this screening population, infection prevalence is estimated at 2%, and the assay has 90% sensitivity and 95% specificity. The animal is held separately from the destination herd. Which interpretation should guide the decision about permanently excluding it from the translocation?

Accepted Answer

The probability of infection is about 27%; seek confirmation before permanently excluding the animal.

Answer

The probability of infection is about 90%; exclude the animal on the strength of the sensitivity.

Answer

The probability of infection is about 95%; exclude the animal on the strength of the specificity.

Answer

The probability of infection remains about 2%; retain the pretest estimate despite the positive result.

Question 9

Painful blubber and biopsy-confirmed fat necrosis develop in a harbor seal fed inadequately stored oily fish. Feed analysis documents substantial lipid oxidation, and the ration has not received its intended vitamin supplementation. Which deficiency-pathogenesis pairing best fits the lesion?

Accepted Answer

Vitamin E depletion reduces the protection of cellular membrane lipids against oxidative damage.

Answer

Thiamine depletion impairs oxidative carbohydrate metabolism in metabolically active tissues.

Answer

Vitamin A depletion disrupts epithelial differentiation, permitting secondary bacterial invasion.

Answer

Vitamin C depletion impairs collagen synthesis and weakens connective-tissue support.

Question 10

A newly acquired macaw has stable body weight, normal gastrointestinal transit on imaging, and no neurologic abnormalities. Two independently collected cloacal samples test positive for parrot bornavirus RNA by RT-PCR. The owner asks whether these results mean the bird has proventricular dilatation disease. Which explanation is justified?

Accepted Answer

The results support infection but do not diagnose clinical proventricular dilatation disease.

Answer

Repeated PCR positivity establishes PDD despite the absence of clinical abnormalities.

Answer

Infection remains unproven until a separate assay detects circulating antibodies.

Answer

Persistent RNA detection predicts progressive clinical disease despite the normal examination.

Free DACZM Practice Questions

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

That's 10 of 1,030