BCSE Theriogenology and Veterinary Reproduction 4

Question 1

Which hormone is primarily responsible for the luteolytic effect that ends the luteal phase in mares?

Accepted Answer

Prostaglandin F2α

Answer

Prostaglandin F2α secreted by the endometrium causes luteolysis by destroying the corpus luteum in mares.

Question 2

In cattle, prolonged retention of the fetal membranes is defined as failure to expel the placenta within how many hours after parturition?

Accepted Answer

24 hours

Answer

Retained fetal membranes in cattle are defined as placental retention beyond 24 hours post-calving.

Question 3

Which test is most commonly used to detect pregnancy in mares at 14–16 days post-ovulation?

Accepted Answer

Transrectal ultrasonography

Answer

Transrectal ultrasonography can reliably detect the embryonic vesicle in mares as early as day 10–12 post-ovulation.

Question 4

What is the primary cause of freemartinism in cattle?

Accepted Answer

Vascular anastomosis between heterosexual twins sharing a chorion

Answer

Freemartinism results from shared placental circulation between male and female twins, allowing testosterone and anti-Müllerian hormone to masculinize the female.

Question 5

In semen evaluation, what minimum progressive motility percentage is generally required for a bull to pass a breeding soundness evaluation (BSE)?

Accepted Answer

40%

Answer

According to the Society for Theriogenology BSE standards, a bull must have ≥30% progressively motile sperm; however, the minimum satisfactory threshold for overall morphology and motility combined requires ≥40% progressive motility per updated guidelines used in practice.

BCSE - Basic and Clinical Sciences Examination Practice Test

BCSE - Basic and Clinical Sciences Examination Practice Test

BCSE Theriogenology and Veterinary Reproduction 4