DVM Reproductive Medicine and Theriogenology 2

Question 1

Superovulation in cattle for embryo transfer is most commonly induced by:

Accepted Answer

Exogenous FSH or eCG administered during the mid-luteal phase to stimulate multiple follicle development

Answer

Progesterone implants to increase the number of implantation sites

Answer

GnRH administration on day 7 to recruit additional follicles

Answer

Surgical removal of one ovary to concentrate follicular stimulation

Question 2

In swine, maternal recognition of pregnancy requires a minimum number of viable embryos because:

Accepted Answer

Fewer than 4–5 embryos produce insufficient estrogen to rescue corpora lutea from prostaglandin-mediated regression

Answer

The uterus can only implant a limited number of conceptuses regardless of embryo number

Answer

Sows require a viral signal from embryos rather than a hormonal one

Answer

The corpus luteum in pigs is not luteotropic and requires mechanical distension

Question 3

Rectal palpation of pregnancy in mares typically becomes reliably diagnostic at approximately:

Accepted Answer

Day 25–30

Answer

Day 10–14

Answer

Day 60–70

Answer

Day 90–100

Question 4

Prolonged diestrus (persistent corpus luteum) in mares is characterized by:

Accepted Answer

Failure of the CL to regress beyond the normal luteal phase, with sustained progesterone suppressing estrus

Answer

Premature luteolysis leading to anovulatory estrus

Answer

Corpus luteum formation without prior ovulation

Answer

Abnormally short diestrus with frequent estrus cycles

Question 5

The standard cryoprotectant used in equine semen cryopreservation is:

Accepted Answer

Glycerol

Answer

Dimethyl sulfoxide (DMSO)

Answer

Ethylene glycol

Answer

Propylene glycol

Question 6

In dogs, which serum progesterone concentration most closely corresponds to the preovulatory LH surge?

Accepted Answer

1–2 ng/mL (initial progesterone rise)

Answer

Less than 0.5 ng/mL (basal level)

Answer

5–10 ng/mL (post-ovulation)

Answer

Greater than 20 ng/mL (mid-diestrus)

Question 7

The most common cause of early embryonic mortality in cattle is considered to be:

Accepted Answer

Failure of maternal recognition of pregnancy due to inadequate interferon-tau (IFN-τ) production

Answer

Chromosomal abnormalities in the conceptus

Answer

Luteal phase deficiency resulting in insufficient progesterone support

Answer

Subclinical uterine infections present at the time of AI