NAVLE Bovine Herd Health Management 5 — Questions and Answers
Question 1: A veterinarian is assessing a feedlot for bovine respiratory disease (BRD). Which scoring system is most widely used to objectively evaluate respiratory signs in individual cattle at the pen level?
- FAMACHA scoring system
- Bovine Respiratory Disease Scoring System (BRDS) by McGuirk (Correct answer)
- Body condition scoring (BCS)
- California Mastitis Test (CMT) adaptation for BRD
Correct answer: Bovine Respiratory Disease Scoring System (BRDS) by McGuirk
The McGuirk Bovine Respiratory Disease Scoring System evaluates rectal temperature, nasal discharge, eye discharge, ear position, and head carriage to provide an objective BRD score for pull decisions.
Question 2: Pinkeye (infectious bovine keratoconjunctivitis) caused by Moraxella bovis is most prevalent in summer months. Which management practice MOST effectively reduces its spread in a beef herd?
- Systemic antibiotic treatment of clinically affected animals and fly control (Correct answer)
- Vaccination alone with no other interventions
- Surgical correction of entropion in all affected animals
- Mandatory 30-day quarantine of all affected cattle
Correct answer: Systemic antibiotic treatment of clinically affected animals and fly control
Prompt treatment of clinical cases with long-acting oxytetracycline combined with fly control (the primary vector for Moraxella bovis transmission) is the most effective two-pronged management approach.
Question 3: A cow presents with acute right-sided abomasal displacement progressing to volvulus (RDA/RAV) in a freshly calved dairy cow. Which finding on physical exam is most consistent with this diagnosis?
- Left-sided ping in the paralumbar fossa on simultaneous auscultation and percussion
- High-pitched ping over a large area on the right side between ribs 9-12, with signs of toxemia and tachycardia (Correct answer)
- Bilateral pings with fluid splashing sounds in the lower abdomen
- Left-sided rumen atony with no ping detected
Correct answer: High-pitched ping over a large area on the right side between ribs 9-12, with signs of toxemia and tachycardia
Right abomasal volvulus produces a large-area right-sided ping (ribs 9-12), signs of severe toxemia, tachycardia, and rapid cardiovascular deterioration due to venous outflow obstruction.
Question 4: Bovine trichomoniasis (caused by Tritrichomonas foetus) is a venereal disease affecting beef cattle. Which control strategy is most effective in eliminating trichomoniasis from an infected beef herd?
- Systemic metronidazole treatment of all infected bulls
- Culling infected bulls and resting infected cows for 90+ days to allow self-clearance (Correct answer)
- Vaccination of all cows with the T. foetus vaccine to prevent abortion
- Antibiotic treatment of all cattle and 30-day quarantine
Correct answer: Culling infected bulls and resting infected cows for 90+ days to allow self-clearance
Bulls are permanent carriers and cannot be treated; culling PCR-positive bulls and resting exposed cows (which self-clear in approximately 90 days of sexual rest) is the standard eradication approach.
Question 5: A veterinarian performing a herd health evaluation calculates the 21-day pregnancy rate for a dairy herd. Which formula correctly calculates 21-day pregnancy rate?
- Conception rate × 100
- Conception rate × heat detection rate (or submission rate) (Correct answer)
- Number of pregnancies ÷ total cows × 100
- Days in milk at first AI ÷ voluntary waiting period
Correct answer: Conception rate × heat detection rate (or submission rate)
21-day pregnancy rate = conception rate × submission rate (heat detection rate), meaning it captures both the ability to detect cows in heat and the success of conception when bred.
Question 6: Which reportable disease of cattle causes vesicular lesions on the tongue, feet, and teats, and must be immediately reported to state and federal authorities if suspected?
- Bovine papular stomatitis
- Foot-and-Mouth Disease (FMD) (Correct answer)
- Infectious Bovine Rhinotracheitis (IBR)
- Vesicular stomatitis virus (VSV) infection
Correct answer: Foot-and-Mouth Disease (FMD)
Foot-and-Mouth Disease is a foreign animal disease (FAD) and federally reportable emergency; any suspected case must be immediately reported to USDA APHIS and state veterinary officials due to its catastrophic trade and production consequences.
Question 7: A beef producer wants to improve weaning weights and post-weaning growth. Which management practice during the preconditioning period (45-60 days post-weaning) has the GREATEST impact on feedlot health outcomes?
- Administering growth implants immediately at weaning
- Completing vaccination series, weaning, castration, and dehorning at least 45 days before sale (Correct answer)
- Keeping calves on the cow for 9 months before weaning
- Providing ad libitum grain access from birth
Correct answer: Completing vaccination series, weaning, castration, and dehorning at least 45 days before sale
Preconditioning programs that complete the BRD vaccination series, castration, and dehorning at least 45 days before sale reduce feedlot morbidity and mortality by allowing stress recovery and vaccine immune response maturation.
NAVLE Bovine Herd Health Management 5
A veterinarian is assessing a feedlot for bovine respiratory disease (BRD).
Which scoring system is most widely used to objectively evaluate respiratory signs in individual cattle at the pen level?