Cardiorespiratory SBAs Flashcards
Scenario: A farmer presents a 5-year-old Simmental cow with a history of epistaxis. On examination, you find the cow has pale mucous membranes, tachycardia, tachypnoea, and melena.
Lead-in: Which of the following is the most likely diagnosis?
Options:
a) Anthrax
b) Babesiosis
c) Caudal vena cava thrombosis
d) Factor XI deficiency
e) Rodenticide poisoning
Answer: c) Caudal vena cava thrombosis
Explanation: The cow’s clinical signs, including epistaxis, pale mucous membranes, and melena, are highly suggestive of a haemorrhagic condition. Given the signalment and history, caudal vena cava thrombosis is the most likely diagnosis.
Scenario: You are examining a 9-day-old female Holstein calf that is recumbent and has diarrhoea. She has a weak suckle reflex, prolonged skin tent, tachycardia, and cold extremities. Her palpebral reflex is present but slow.
Lead-in: What is the most appropriate fluid therapy plan for this calf?
Options:
a) Oral fluid therapy with a water with a ‘bovi-aid’ rehydration powder.
b) Intravenous fluid therapy with an haartmans (lactated ringers).
c) Intravenous fluid therapy with a 7.2% saline followed by oral fluids
d) No fluid therapy is required at this time
e) Intravenous fluid therapy with a 0.9% saline.
D
Scenario: A 50kg calf presents with lateral recumbency, CRT of 5 seconds, heart rate of 180 bpm, and dry mucous membranes.
Lead-in: What is the estimated fluid deficit for this calf?
Options:
a) 2.5 Litres
b) 5 Litres
c) 6 Litres
d) 7.5 Litres
e) 13.5 Litres
Explanation: The calf is showing signs of severe dehydration (12-15% deficit). The fluid deficit is calculated as a percentage of body weight: 15% of 50kg = 7.5 Litres.
Scenario: A 14-day-old calf presents with recumbency, an absent palpebral response, and diarrhoea. You estimate the base excess to be -20 mmol/L.
Lead-in: What is the total bicarbonate requirement for this calf?
Options:
a) 13g of bicarbonate of soda
b) 25g of bicarbonate of soda
c) 50g of bicarbonate of soda
d) 300 mmol of bicarbonate
e) 600 mmol of bicarbonate
Answer: e) 600 mmol of bicarbonate
Explanation: The bicarbonate requirement is calculated as follows: body weight (kg) x base deficit (mmol/L) x volume of distribution (L/kg) = 50 x 20 x 0.6 = 600 mmol
Scenario: You are treating a cow for acute ruminal acidosis. You have administered 4 ml/kg of a 7.2% hypertonic saline solution intravenously.
Lead-in: What is the most appropriate next step in the fluid therapy plan?
Options:
a) Administer a further 4 ml/kg of hypertonic saline intravenously.
b) Administer 20-40 Litres of oral fluids.
c) Administer an isotonic crystalloid intravenously.
d) No further fluid therapy is required.
e) Administer a colloid intravenously.
Answer: b) Administer 20-40 Litres of oral fluids.
Explanation: After administering hypertonic saline, it is crucial to follow up with a large volume of oral fluids to rehydrate the animal and prevent dehydration.
Scenario: A 35kg calf presents with a skin tent >3 seconds, heart rate of 120 bpm, cold extremities, and diarrhoea.
Lead-in: What is the calf’s total fluid deficit?
Options:
a) 2.1 Litres
b) 3.5 Litres
c) 4.2 Litres
d) 6 Litres
e) 10.5 Litres
b) 3.5 Litres
Explanation: The calf’s total fluid deficit is calculated as follows: body weight (kg) x % dehydration = 35kg x 10% = 3.5 Litres.
Scenario: A 400kg cow has a prolonged CRT (>3 seconds), dry mucous membranes, cold extremities, tachycardia >50% above normal, and very concentrated urine.
Lead-in: What is the cow’s estimated percentage dehydration?
Options:
a) 5-7%
b) 8-10%
c) 10-12%
d) 12-15%
e) >15%
Answer: c) 10-12%
Explanation: The cow’s clinical signs are consistent with moderate dehydration, which corresponds to an estimated fluid deficit of 10-12%.
Scenario: A 50kg calf has a base excess of -15 mmol/L.
Lead-in: How much bicarbonate of soda should be added to the intravenous fluids?
Options:
a) 13g
b) 18.75g
c) 25g
d) 37.5g
e) 50g
Answer: b) 18.75g
Explanation: The bicarbonate requirement is calculated as follows: body weight (kg) x base deficit (mmol/L) x volume of distribution (L/kg) = 50 x 15 x 0.6 = 450 mmol. Then, divide the total mmol of bicarbonate required by the mmol of bicarbonate per gram of bicarbonate of soda: 450 mmol / 12 mmol/g = 37.5g. Finally, divide the total grams of bicarbonate of soda by 2 to determine how much should be added to each 1L bag of saline: 37.5g / 2 = 18.75g.
Scenario: A 600kg lactating cow requires intravenous fluid therapy.
Lead-in: What is the minimum volume of intravenous fluids required to meet this cow’s daily maintenance needs?
Options:
a) 30 Litres
b) 36 Litres
c) 42 Litres
d) 48 Litres
e) 60 Litres
Answer: a) 30 Litres
Explanation: The minimum daily fluid requirement for an adult cow is 50 ml/kg/day. For a 600kg cow, this equates to 50 ml/kg/day x 600 kg = 30,000 ml/day = 30 Litres
Scenario: A 45kg calf with pneumonia requires treatment with oxytetracycline. You have a 50ml bottle of Vetericyn Oxytetracycline Injection at a concentration of 200mg/ml. The dose rate for oxytetracycline in calves is 20mg/kg.
Lead-in: What volume of oxytetracycline solution should you administer to this calf?
Options:
a) 2.25ml
b) 4.5ml
c) 9ml
d) 22.5ml
e) 45ml
Explanation: First, calculate the total dose of oxytetracycline required: 20mg/kg x 45kg = 900mg. Then, calculate the volume of the solution needed: 900mg / 200mg/ml = 4.5ml.
Scenario: A 40kg calf presents with severe dehydration and acidosis. You estimate the base deficit to be 25 mmol/L. You decide to administer a hypertonic solution of bicarbonate intravenously.
Lead-in: What is the most appropriate bicarbonate dose and administration rate for this calf?
Options:
a) 1 ml/kg/min for 4-5 minutes
b) 4 ml/kg rapidly over 5 minutes
c) 75g bicarbonate of soda over 2-6 hours
d) 125g bicarbonate of soda over 2-6 hours
e) 50g bicarbonate of soda over 24 hours
Answer: a) 1 ml/kg/min for 4-5 minutes
Explanation: This is the correct dose and administration rate for hypertonic bicarbonate in a calf. It provides rapid correction of acidosis and plasma expansion.
Scenario: A 2-week-old calf presents with watery diarrhoea and moderate dehydration. You decide to administer oral fluid therapy.
Lead-in: Which of the following features of the oral electrolyte solution is most important for successful rehydration in this calf?
Options:
a) Osmolality of 200 mOsm/kg
b) Sodium content of 50 mmol/L
c) Strong ion difference of 40 mmol/L
d) Presence of glucose
e) Strong ion difference of 80 mmol/L
Answer: e) Strong ion difference of 80 mmol/L
Explanation: A strong ion difference greater than 60 mmol/L is essential for effective rehydration in calves with diarrhoea.
Scenario: You are preparing to administer intravenous fluid therapy to a dehydrated calf. You have Hartmann’s solution and saline available.
Lead-in: Which of the following statements regarding fluid choice is most accurate?
Options:
a) Hartmann’s solution is preferred over saline in acidotic calves.
b) Saline is preferred over Hartmann’s solution when bicarbonate is being used.
c) Hypertonic saline should be used as the sole fluid therapy in dehydrated calves.
d) Hypotonic saline is ideal for rapid rehydration in hypovolaemic calves.
e) Hartmann’s solution is contraindicated in all cases of calf dehydration.
Answer: b) Saline is preferred over Hartmann’s solution when bicarbonate is being used.
Explanation: Calcium in Hartmann’s solution can react with bicarbonate, forming a precipitate and reducing the efficacy of both.
Scenario: A farmer is concerned about a group of piglets that appear pale and are not thriving as well as expected at one week of age.
Lead-in: Which of the following is the most important question to ask the farmer?
Options:
a) Have the piglets been vaccinated against porcine circovirus?
b) Have the piglets been given an iron supplement?
c) Have the piglets been wormed?
d) What is the temperature in the farrowing house?
e) Are the piglets able to access creep feed?
Answer: b) Have the piglets been given an iron supplement?
Explanation: Piglets are born with low iron reserves and sow’s milk is a poor source of iron. Therefore, piglets require an iron supplement within the first few days of life to prevent iron deficiency anaemia.
Scenario: A group of 10-day-old piglets presents with pale mucous membranes, weakness, and elevated heart and respiratory rates. One piglet has died, and post-mortem examination reveals a thin heart wall and oedema of the lungs and muscle tissue.
Lead-in: Which of the following is the most likely diagnosis?
Options:
a) Iron deficiency anaemia
b) Mycoplasma suis infection
c) Warfarin poisoning
d) Porcine proliferative enteritis
e) Vitamin E deficiency
Explanation: The clinical signs and post-mortem findings are consistent with iron deficiency anaemia in piglets.
cenario: A farmer reports that several of his weaned piglets are pale and unthrifty. He has been feeding them a commercial piglet diet and providing them with fresh water.
Lead-in: Which of the following is the most appropriate next step?
Options:
a) Recommend increasing the protein content of the diet.
b) Visit the farm to examine the piglets and investigate further.
c) Prescribe a broad-spectrum antibiotic to treat any underlying infection.
d) Advise the farmer to deworm the piglets.
e) Suggest supplementing the piglets with vitamin E.
Answer: b) Visit the farm to examine the piglets and investigate further.
Explanation: It is important to visit the farm to examine the piglets and gather more information before making any treatment or management recommendations.
Scenario: You are examining a group of piglets that are suspected to be suffering from iron deficiency anaemia.
Lead-in: Which of the following blood test results would be most consistent with this diagnosis?
Options:
a) Low packed cell volume (PCV), low mean corpuscular volume (MCV), low mean corpuscular haemoglobin concentration (MCHC)
b) Low PCV, high MCV, low MCHC
c) Low PCV, normal MCV, normal MCHC
d) Normal PCV, low MCV, low MCHC
e) High PCV, normal MCV, normal MCHC
Answer: a) Low packed cell volume (PCV), low mean corpuscular volume (MCV), low mean corpuscular haemoglobin concentration (MCHC)
Explanation: Iron deficiency anaemia is characterized by small, pale red blood cells, which result in a low PCV, low MCV, and low MCHC.
Scenario: A farmer asks for advice on preventing iron deficiency anaemia in his newborn piglets.
Lead-in: Which of the following is the most effective method for preventing iron deficiency anaemia in piglets?
Options:
a) Providing the sow with an iron supplement during gestation.
b) Injecting the piglets with iron dextran within the first week of life.
c) Adding iron sulfate to the piglets’ drinking water.
d) Feeding the piglets an iron-rich creep feed.
e) Increasing the iron content of the sow’s milk by altering her diet.
Answer: b) Injecting the piglets with iron dextran within the first week of life.
Explanation: Injecting piglets with iron dextran is the most effective way to provide them with the iron they need to prevent iron deficiency anaemia.
Scenario: A group of 10-week-old calves housed in a well-ventilated barn with good hygiene practices develop clinical signs of respiratory disease, including coughing, nasal discharge, and fever. You suspect bovine respiratory syncytial virus (BRSV) is involved.
Lead-in: Which of the following statements regarding BRSV infection in this group of calves is most accurate?
Options:
a) Natural infection will provide long-lasting immunity, preventing future BRSV infections.
b) Vaccination is not recommended in this age group due to interference from maternal antibodies.
c) Treatment with antimicrobials targeting BRSV is essential for recovery.
d) Reinfection with BRSV is possible, and while vaccination may not prevent it, it can reduce the severity of clinical disease.
e) BRSV infection is typically fatal, with most calves developing severe interstitial pneumonia and dying within 2-5 days.
Answer: d) Reinfection with BRSV is possible, and while vaccination may not prevent it, it can reduce the severity of clinical disease.
Explanation: BRSV reinfection is common due to short-lived immunity. Vaccination can reduce disease severity but may not completely prevent reinfection.
Scenario: A 2-year-old Texel ram presents with severe respiratory distress, laryngeal stridor, and open-mouthed breathing. The owner reports a sudden onset of clinical signs. You suspect laryngeal chondritis.
Lead-in: Which of the following is the most appropriate immediate management strategy for this ram?
Options:
a) Administer a high dose of NSAIDs and send the ram for immediate slaughter.
b) Perform an emergency tracheostomy under general anesthesia to secure the airway.
c) Prescribe a course of broad-spectrum antibiotics and advise the owner to reduce the ram’s concentrate feed intake.
d) Perform surgical debridement of the necrotic laryngeal cartilages to remove the obstruction.
e) Administer 20mg of dexamethasone intravenously, followed by an emergency tracheostomy under local anesthesia if necessary.
Answer: e) Administer 20mg of dexamethasone intravenously, followed by an emergency tracheostomy under local anesthesia if necessary.
Explanation: Immediate management of laryngeal chondritis involves securing the airway. Dexamethasone helps reduce laryngeal inflammation, and a tracheostomy may be necessary if obstruction persists. Local anesthesia is preferred to minimize stress.
Scenario: A group of 6-month-old dairy heifers are experiencing an outbreak of respiratory disease. Several heifers have a high fever (>40°C), bilateral conjunctivitis with epiphora, and a red nose. You suspect infectious bovine rhinotracheitis (IBR).
Lead-in: Which of the following diagnostic tests is most appropriate to confirm IBR infection in this group of heifers during the acute phase of the outbreak?
Options:
a) Serology to detect rising antibody titers against IBR.
b) Bulk milk tank testing for IBR antibodies.
c) Conjunctival swab submitted for PCR testing for IBR.
d) Skin testing to assess for IBR hypersensitivity.
e) Fecal sampling to detect IBR virus shedding.
Answer: c) Conjunctival swab submitted for PCR testing for IBR.
Explanation: During an acute outbreak, virus detection is key. Conjunctival swabs are a good source of virus for PCR testing in IBR.
Scenario: A farmer calls you about a group of 4-month-old lambs that have been housed for the winter. They are coughing, and some have a nasal discharge. You suspect pasteurellosis.
Lead-in: Which of the following antibiotics would be the most appropriate first-line treatment for this group of lambs?
Options:
a) Florfenicol
b) Tilmicosin
c) Procaine penicillin
d) Oxytetracycline
e) Enrofloxacin
Answer: d) Oxytetracycline
Explanation: For pasteurellosis in lambs, oxytetracycline is a good first-line choice due to its efficacy and category D status, minimizing the risk of antimicrobial resistance.
Scenario: A 5-year-old dairy cow presents with a chronic cough, weight loss, and enlarged supramammary lymph nodes. The cow has been grazing lush pasture with a herd of sheep. You suspect malignant catarrhal fever (MCF).
Lead-in: Which of the following statements regarding MCF is most accurate?
Options:
a) The disease is highly contagious between cattle, and the entire herd is at risk.
b) Treatment with high-dose corticosteroids is usually curative if started early in the course of the disease.
c) The disease is caused by a virus transmitted from sheep, and there is no effective treatment or vaccine currently available.
d) The cow will likely recover with supportive care, but it will remain a carrier and shed the virus for life.
e) The disease is zoonotic, posing a significant risk to human health.
Answer: c) The disease is caused by a virus transmitted from sheep, and there is no effective treatment or vaccine currently available.
Explanation: MCF is caused by a virus (OvHV-2) carried by sheep. The disease is typically fatal in cattle, and there is no effective treatment or vaccine.
Scenario: You are called to a farm with a group of 8-week-old calves experiencing an outbreak of pneumonia. The calves are housed in a poorly ventilated barn with a high stocking density. You suspect a multifactorial etiology with both viral and bacterial pathogens involved.
Lead-in: Which of the following is the most likely sequence of events leading to the development of pneumonia in these calves?
Options:
a) Bacterial infection causing immunosuppression, followed by viral invasion of the lower respiratory tract.
b) Viral infection causing direct damage to the lungs, leading to bacterial pneumonia.
c) Viral infection causing upper respiratory tract disease, immunosuppression, and subsequent bacterial colonization of the lower respiratory tract.
d) Bacterial infection causing primary pneumonia, followed by viral invasion of the weakened lung tissue.
e) Fungal infection causing primary pneumonia, followed by secondary bacterial infection.
Answer: c) Viral infection causing upper respiratory tract disease, immunosuppression, and subsequent bacterial colonization of the lower respiratory tract.
Explanation: In BRD, a viral infection often initiates an upper respiratory tract disease (URTI), which can impair immune defenses and allow bacterial commensals to invade the lower respiratory tract, causing pneumonia.
Scenario: A 4-month-old lamb is found dead in a field. On post-mortem examination, you find the following:
Lead-in: Which of the following pathogens is most likely responsible for this lamb’s death?
Options:
a) Mannheimia haemolytica
b) Bibersteinia trehalosi
c) Mycoplasma ovipneumoniae
d) Dictyocaulus filaria
e) Histophilus somni
Answer: c) Mycoplasma ovipneumoniae
Explanation: The post-mortem findings of dark red, raised areas on the apical and cardiac lobes are characteristic of M. ovipneumoniae infection in lambs.
A cow presents with the following ocular lesion:
Lead-in: Which of the following is the most appropriate management option for this cow?
Options:
a) Surgical excision of the mass with wide margins.
b) Cryotherapy to freeze and destroy the tumor.
c) Enucleation.
d) Topical chemotherapy to shrink the tumour.
e) No treatment is necessary as the tumour is benign.
C
