ALAT ALAT Research Procedures and Techniques Questions and Answers 5 — Questions and Answers
Question 1: During a cardiac puncture for terminal blood collection in a rat, where should the needle be directed and why?
- Into the right ventricle, because it has the highest blood volume
- Toward the left ventricle at the apex, to access the highest-pressure chamber (Correct answer)
- Into the aorta, to collect oxygenated arterial blood only
- Into the superior vena cava for easy access to venous blood
Correct answer: Toward the left ventricle at the apex, to access the highest-pressure chamber
The left ventricle is targeted during cardiac puncture because it is the highest-pressure chamber and provides the greatest blood yield.
Question 2: A technician needs to collect urine from a mouse for a 24-hour metabolic study. Which housing device is most appropriate?
- Standard shoebox cage with extra absorbent bedding
- Metabolic cage designed to separate urine and feces (Correct answer)
- Cage with a wire mesh floor over a collection tray
- Sterile transport box lined with filter paper
Correct answer: Metabolic cage designed to separate urine and feces
Metabolic cages are specifically designed to separately collect urine and feces from research animals over timed periods.
Question 3: Which of the following is the correct aseptic technique step that MUST occur immediately before making a skin incision during a surgical procedure?
- Administering a postoperative analgesic
- Draping the surgical site with sterile towels or drapes (Correct answer)
- Flushing the wound with saline
- Removing the animal from the anesthesia machine
Correct answer: Draping the surgical site with sterile towels or drapes
Sterile draping of the surgical field immediately before incision creates a sterile barrier that minimizes contamination of the operative site.
Question 4: An ALAT notices that a rabbit being used for antibody production has a swollen, warm injection site 48 hours after an adjuvant injection. What is the most likely cause?
- Normal immune response to the antigen alone
- Abscess or granuloma formation, a known complication of adjuvant use (Correct answer)
- An allergic reaction requiring immediate euthanasia
- Improper storage of the antigen causing degradation
Correct answer: Abscess or granuloma formation, a known complication of adjuvant use
Adjuvants such as Freund's Complete Adjuvant are known to cause local tissue reactions including abscess and granuloma formation at injection sites.
Question 5: What is the purpose of a 'positive control' in a research experiment involving a new drug compound being tested on laboratory animals?
- To serve as an untreated group that receives only vehicle solution
- To verify the experimental system works by using a compound with a known effect (Correct answer)
- To expose one group to the highest possible drug dose
- To provide a group that receives the drug plus a competing treatment
Correct answer: To verify the experimental system works by using a compound with a known effect
A positive control uses a substance with a known, predictable effect to confirm that the experimental system is functioning correctly.
Question 6: When performing a tail vein injection in a mouse, which preparation step best facilitates visualization and dilation of the lateral tail vein?
- Cooling the tail in ice water for 30 seconds
- Briefly warming the tail with warm water or a heat lamp (Correct answer)
- Applying a tourniquet to the base of the tail for 5 minutes
- Shaving the tail with a razor blade before injection
Correct answer: Briefly warming the tail with warm water or a heat lamp
Gentle warming of the mouse tail causes vasodilation of the lateral tail veins, making them more prominent and easier to cannulate.
Question 7: An IACUC protocol specifies that animals must receive multimodal analgesia. Which combination best exemplifies this approach for a post-surgical mouse?
- Two doses of the same NSAID given 12 hours apart
- An NSAID (e.g., meloxicam) combined with an opioid (e.g., buprenorphine) (Correct answer)
- Isoflurane maintained at 0.5% for 24 hours post-surgery
- A single high dose of buprenorphine at the time of surgery only
Correct answer: An NSAID (e.g., meloxicam) combined with an opioid (e.g., buprenorphine)
Multimodal analgesia combines drugs from different classes (e.g., NSAID + opioid) to target multiple pain pathways, providing superior pain control with lower doses of each drug.
ALAT ALAT Research Procedures and Techniques Questions and Answers 5
During a cardiac puncture for terminal blood collection in a rat, where should the needle be directed and why?