All Free Veterinary Science MCQs with Answers

• A. Canine mast cell tumor
• B. Canine multicentric lymphoma
• C. Canine osteosarcoma
• D. Canine transmissible venereal tumor

Explanation: Canine transmissible venereal tumor spreads by physical transfer of viable neoplastic cells, usually during sexual contact.

• A. Corynebacterium pseudotuberculosis
• B. Listeria monocytogenes
• C. Bacillus anthracis
• D. Salmonella Dublin

Explanation: Corynebacterium pseudotuberculosis causes chronic abscesses in lymph nodes and internal organs of sheep and goats, producing caseous…

• A. Tips of mature villi
• B. Crypt epithelium
• C. Muscularis externa
• D. Serosal connective tissue

Explanation: Canine parvovirus targets rapidly dividing crypt epithelial cells, causing crypt necrosis and subsequent villous collapse.

• A. Size of individual parenchymal cells
• B. Amount of extracellular fluid
• C. Number of cells within a tissue
• D. Volume of intracellular fat

Explanation: Hyperplasia results from increased cell division, producing more cells in a tissue.

• A. Masson's trichrome
• B. Oil Red O
• C. Prussian blue
• D. Toluidine blue

Explanation: Toluidine blue stains mast cell granules metachromatically because of their sulfated glycosaminoglycans.

• A. Grocott methenamine silver
• B. Ziehl-Neelsen stain
• C. Wright-Giemsa stain
• D. Alcian blue stain

Explanation: Grocott methenamine silver strongly outlines fungal walls and makes hyphae readily visible.

• A. Ecchymosis
• B. Petechia
• C. Hematoma
• D. Suffusion

Explanation: Petechiae are very small, pinpoint hemorrhages caused by leakage from small vessels.

• A. Thrombus formation without vessel injury
• B. Smooth muscle hypertrophy without inflammation
• C. Fibrinoid change with nuclear debris in vessel walls
• D. Amyloid deposition around arterial nerves

Explanation: Leukocytoclastic vasculitis shows inflammation of small vessels with fragmented leukocyte nuclei, often accompanied by fibrinoid necrosis.

• A. A blood clot lodged within a nutrient artery
• B. A cavity filled with newly formed cartilage
• C. A benign tumour arising from bone marrow
• D. A fragment of dead bone separated from living bone

Explanation: A sequestrum is devitalized bone that becomes separated from surrounding viable bone, commonly during chronic osteomyelitis.

• A. Pyogranulomatous inflammation with serosal effusion
• B. Purely suppurative inflammation of the skin
• C. Diffuse mineralization of skeletal muscle
• D. Necrotizing inflammation limited to the hoof

Explanation: Feline infectious peritonitis commonly produces pyogranulomatous inflammation and protein-rich effusion in abdominal or thoracic serous…

• A. A clear watery fluid on an intact serosa
• B. A fibrinonecrotic membrane attached to mucosal surfaces
• C. A localized collection of pus in a capsule
• D. A diffuse increase in tissue blood flow

Explanation: Diphtheritic inflammation causes mucosal necrosis followed by deposition of fibrin, producing a firmly attached fibrinonecrotic membrane.

• A. Local supply of adipose tissue
• B. Entire original population of mature cells
• C. Underlying basement membrane and stromal framework
• D. Surrounding layer of skeletal muscle

Explanation: An intact basement membrane and stromal framework guide the migration and organization of surviving epithelial cells during regeneration.

• A. Lamellar bone with normal osteocytes
• B. Mature cartilage without cellular atypia
• C. Uniform fat cells between bone trabeculae
• D. Neoplastic cells producing malignant osteoid

Explanation: Malignant osteoid produced directly by atypical neoplastic cells is the defining histological feature of osteosarcoma.

• A. Zero-order elimination
• B. First-order elimination
• C. Passive diffusion
• D. Renal filtration

Explanation: Zero-order elimination removes a fixed amount of drug per unit time. First-order elimination removes a constant fraction of the drug, so…

• A. Time-dependent killing
• B. Concentration-dependent killing
• C. Bacteriostatic activity only
• D. pH-dependent inhibition

Explanation: Aminoglycosides kill bacteria more effectively when higher peak concentrations are achieved relative to the pathogen's MIC.

• A. Blocking folate synthesis
• B. Inhibiting bacterial cell-wall formation
• C. Opening glutamate-gated chloride channels
• D. Blocking parasite tubulin assembly

Explanation: Ivermectin increases chloride ion entry through glutamate-gated chloride channels in invertebrates, causing paralysis and death.

• A. Ketamine
• B. Propranolol
• C. Furosemide
• D. Atropine

Explanation: Atropine competitively blocks muscarinic acetylcholine receptors and reduces salivation, bronchial secretions, bradycardia and…

• A. Time-dependent killing
• B. Concentration-dependent killing
• C. Delayed receptor antagonism
• D. Dose-independent killing

Explanation: The effectiveness of beta-lactams is mainly related to the time that free drug concentration remains above the pathogen's MIC.

• A. Alpha-1 adrenergic receptors
• B. Alpha-2 adrenergic receptors
• C. Beta-1 adrenergic receptors
• D. Muscarinic receptors

Explanation: Xylazine is an alpha-2 adrenergic agonist that reduces norepinephrine release and produces sedation, analgesia and muscle relaxation.

• A. Neostigmine
• B. Pilocarpine
• C. Atropine
• D. Bethanechol

Explanation: Atropine blocks excessive stimulation of muscarinic receptors and is the main treatment for salivation, bronchoconstriction and…