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Hormone Manipulation: Case 2

You have chosen to use PGF2a (Lutalyse) but first you must remember what it does.

PGF2a is released from the uterus in vivo (in the animal) and normally causes regression of the corpus luteum.
True
False

Since mares grow follicles even in diestrus, giving PGF2a without knowing the size of the follicles on the ovary can be dangerous because:
Choice 1 the mare can ovulate without showing estrus if she has a large follicle when PGF2a is given
Choice 2 it causes multiple ovulations
Choice 3 PGF2a decreases estrogen levels
Choice 4 inhibit behavioral estrus

PGF2a only works between day 5-12 of the estrous cycle. Assume you have no information about where the mare is in the cycle. (more than one correct answer)
Choice 1 A single shot of PGF2a has a 33% chance to cause luteolysis.
Choice 2 A single shot of PGF2a may cause ovulation without estrus.
Choice 3 A single shot of PGF2a may not change the mare's cycle at all.
Choice 4 Two shots of PGF2a, 12 days apart, will result in estrus in 2-4 days after the second shot.

You come up with a plan!

You are going to use the 2 shot method. If you can only get the fresh semen June 5-9, when should you give the shots so that you breed during this window?

 

May 15 & 28

May 17 & June 1

May 25 & June 7