Veterinary Microbiology Quiz 33 Quiz InstructionsThis quiz consists of 20 multiple-choice questions.You will be awarded 5 marks for each correct answer. Question 1: Which of the following is a constant clinical chemistry or urinalysis finding in sheep affected by pulpy kidney disease (Clostridium perfringens type D)?GlycosuriaKetonuriaProteinuriaHematuria Question 2: Which staining technique is specifically used for the histological demonstration of Clostridium piliforme within hepatocytes to confirm Tyzzer's disease?Ziehl-Neelsen stainingWarthin-Starry silver impregnation techniqueMacchiavello stainingGimenez staining Question 3: The toxin produced by the atypical, coiled Clostridium spiroforme in rabbits is neutralized by antitoxin raised against which clostridial toxin?Clostridium perfringens type E iota toxinClostridium perfringens type C beta toxinClostridium perfringens type B beta toxinClostridium perfringens type D epsilon toxin Question 4: Contrast the morphology of Mycobacterium bovis with Mycobacterium avium subsp. paratuberculosis as described in the text. Which statement is correct?M. bovis rods are slender and up to 4 µm long, whereas M. avium subsp. paratuberculosis rods are broad and usually less than 2 µm long.M. bovis rods are broad and less than 2 µm long, whereas M. avium subsp. paratuberculosis rods are slender and up to 4 µm long.Both species are identical in size, being slender and exactly 3 µm in length.M. bovis is non-acid-fast, whereas M. avium subsp. paratuberculosis is strongly acid-fast. Question 5: What makes Clostridium piliforme atypical compared to other members of the genus Clostridium regarding its growth and cultivation?It is a facultative anaerobe that grows rapidly on standard nutrient agar.It is an obligate intracellular pathogen that has not been cultured on artificial media.It is a strictly aerobic spore-former that grows only in high-salt media.It is completely unable to form spores and is highly sensitive to heat. Question 6: Which of the following wildlife species is identified as a major reservoir of Mycobacterium bovis in New Zealand?European badgerBrush-tailed possumCape buffaloWild rabbit Question 7: Feline leprosy is a cutaneous disease of cats thought to be caused by which of the following organisms, traditionally transmitted via rodent bites?Mycobacterium lepraeMycobacterium lepraemuriumMycobacterium marinumMycobacterium microti Question 8: How does the clinical manifestation of paratuberculosis (Johne's disease) in adult sheep and goats differ primarily from that in cattle?Sheep and goats show severe, profuse diarrhoea, whereas cattle never show diarrhoea.Diarrhoea is less marked or may be entirely absent in sheep and goats.Sheep and goats show only nervous symptoms, whereas cattle show wasting without weight loss.Cattle recover spontaneously, whereas sheep and goats always die within 48 hours of diarrhoea onset. Question 9: During the laboratory isolation of Mycobacterium bovis from tissue specimens, which decontamination protocol and culture medium parameters are recommended?Treat with 2-4% sodium hydroxide or 5% oxalic acid, then inoculate Lowenstein-Jensen medium without glycerol and with 0.4% sodium pyruvate.Treat with 10% hydrochloric acid, then inoculate Herrold's egg-yolk medium with mycobactin and glycerol.Treat with 0.3% benzalkonium chloride, then inoculate Lowenstein-Jensen medium containing high concentrations of glycerol and no pyruvate.Treat with 1% phenol, then inoculate nutrient agar under anaerobic conditions. Question 10: Match the Clostridium species (Column I) with their associated clinical scenarios or descriptions (Column II) based on the text:Column I:1. Clostridium difficile2. Clostridium colinum3. Clostridium piliforme4. Clostridium spiroformeColumn II:A. Ulcerative enteritis in quails (quail disease)B. Acute colitis in adult horses post-antibiotic therapyC. Tyzzer's disease leading to severe hepatic necrosisD. Coiled morphology causing enteritis in rabbitsSelect the option that represents the correct pairing:1-B, 2-A, 3-C, 4-D1-A, 2-B, 3-D, 4-C1-C, 2-D, 3-A, 4-B1-D, 2-C, 3-B, 4-A Question 11: Match the Mycobacterium species in Column I with their biochemical/growth characteristics on egg-based media in Column II:Column I:1. Mycobacterium tuberculosis2. Mycobacterium bovis3. Mycobacterium avium complex4. Mycobacterium avium subsp. paratuberculosisColumn II:A. Dysgonic growth on glycerol, growth enhanced by sodium pyruvateB. Eugonic growth on glycerol, pyrazinamidase and nitrate reduction positive, TCH resistantC. Very slow growth (up to 16 weeks), strictly requires mycobactin supplementD. Eugonic growth on glycerol, pyrazinamidase positive, nitrate reduction negative, TCH resistantWhich option correctly pairs Column I and Column II?1-B, 2-A, 3-D, 4-C1-A, 2-B, 3-C, 4-D1-B, 2-D, 3-A, 4-C1-D, 2-C, 3-B, 4-A Question 12: Match the Mycobacterium species (Column I) with their primary or occasional hosts (Column II) based on the text:Column I:1. Mycobacterium microti2. Mycobacterium marinum3. Mycobacterium lepraemurium4. Mycobacterium senegalenseColumn II:A. Fish, aquatic mammals, and humansB. VolesC. Cattle (implicated in bovine farcy)D. Rats, mice, and catsWhich of the following options represents the correct match?1-B, 2-A, 3-D, 4-C1-A, 2-B, 3-C, 4-D1-C, 2-D, 3-B, 4-A1-D, 2-C, 3-A, 4-B Question 13: Match the environmental mycobacterial species (Column I) with their correct classification based on pigment production and growth rate (Column II):Column I:1. Mycobacterium kansasii2. Mycobacterium scrofulaceum3. Mycobacterium genavense4. Mycobacterium phleiColumn II:A. PhotochromogenB. ScotochromogenC. Non-chromogenD. Rapid growerSelect the correct match:1-A, 2-B, 3-C, 4-D1-B, 2-C, 3-D, 4-A1-C, 2-D, 3-A, 4-B1-D, 2-A, 3-B, 4-C Question 14: Evaluate the following statements regarding the tuberculin test and its sensitivity/reactivity in cattle:I. False-negative results can occur if cattle are tested before delayed-type hypersensitivity develops (about 30 days post-infection).II. Anergy, an unresponsive state to tuberculin, is commonly observed in the early, acute phase of Mycobacterium bovis infection.III. Cows may be unresponsive to the tuberculin test during the early postpartum period.IV. A transient desensitization may follow injection of tuberculin, with reactivity usually returning within 60 days.Which of these statements are correct?I, III, and IV onlyI and II onlyII, III, and IV onlyI, II, III, and IV Question 15: Consider the following statements regarding the pathogenesis of Mycobacterium bovis in cattle:I. The initial accumulation of macrophages at the primary site of infection is a response to the foreign body effect of waxes and lipids in the cell wall.II. Mycobacterial survival within host macrophages is promoted by blocking phagosome-lysosome fusion.III. Macrophage recruitment accelerates some weeks after infection, driven by cytokines from sensitized T lymphocytes.IV. Activated macrophages undergo rapid apoptosis, preventing the formation of a typical organized tubercle.Which combination of statements is correct?I, II, and III onlyII and IV onlyI, III, and IV onlyI, II, III, and IV Question 16: Evaluate the vaccination recommendations for controlling Clostridium perfringens enterotoxaemias:I. Ewes should be vaccinated with toxoid six weeks before lambing to ensure passive protection for lambs.II. Ewes being vaccinated for the first time should be given two doses of vaccine one month apart.III. To prevent pulpy kidney disease, lambs should be vaccinated with toxoid before they are two months old.IV. Lambs require a booster injection of toxoid one month after their first vaccination.Which of these statements are correct according to the text?I, II, III, and IVI, II, and III onlyII and IV onlyI and III only Question 17: Which of the following statements correctly describe hemorrhagic enteritis caused by Clostridium perfringens type C in piglets?I. It is a peracute enterotoxaemia that primarily affects newborn piglets worldwide.II. Entire litters are often affected, with mortality rates reaching up to 80%.III. Piglets acquire the infection primarily via the respiratory aerosol route.IV. Postmortem lesions are typically found in the terminal small intestine, caecum, and colon.Select the correct option:I, II, and IV onlyI and II onlyII, III, and IV onlyI, II, III, and IV Question 18: Read the assertion and reason carefully, then select the correct option:Assertion (A): Failure to demonstrate Clostridium perfringens toxins in the ileal contents of recently-dead animals does not definitively exclude a diagnosis of clostridial enterotoxaemia.Reason (R): Some of these clostridial toxins, particularly the beta (β) toxin, are highly labile and may degrade rapidly in intestinal contents.Both A and R are correct, and R is the correct explanation of A.Both A and R are correct, but R is not the correct explanation of A.A is correct but R is incorrect.A is incorrect but R is correct. Question 19: Read the assertion and reason carefully, then select the correct option:Assertion (A): The use of inactivated adjuvanted vaccines for paratuberculosis (Johne's disease) in cattle is subject to regulatory control in some countries.Reason (R): Vaccinated cattle usually become sensitized to tuberculin, which interferes with bovine tuberculosis eradication programs.Both A and R are correct, and R is the correct explanation of A.Both A and R are correct, but R is not the correct explanation of A.A is correct but R is incorrect.A is incorrect but R is correct. Question 20: In a diagnostic laboratory performing the classical toxin neutralization test for Clostridium perfringens using mice or guinea-pigs, a technician prepares the mixture of test supernatant fluid and known antitoxins.According to the standard protocol:I. What is the ratio of test fluid to known antitoxin used?II. What volume of this mixture is injected intravenously into mice?III. What volume is injected intradermally into guinea-pigs?Select the option that correctly provides these three values in sequence:I. 3 parts test fluid to 2 parts antitoxin; II. 0.3 ml; III. 0.2 mlI. 2 parts test fluid to 3 parts antitoxin; II. 0.2 ml; III. 0.3 mlI. 1 part test fluid to 1 part antitoxin; II. 0.5 ml; III. 0.1 mlI. 3 parts test fluid to 1 part antitoxin; II. 0.3 ml; III. 0.3 ml
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