Pregnancy Patterns in the Mare- Lecture 16

Question 1

Ejaculation takes place in…

Answer 1

uterus

Question 2

Infundibulum

Answer 2

Covers ovulation fossa

Question 3

Ampulla

Answer 3

Sperm passage

Question 4

Where does fertilization happen?

Answer 4

Ampullary-isthmic junction

Question 5

Embryo transport to uterus length?

Answer 5

5.5 to 6 days.

Question 6

Compact morula

Answer 6

6 day old structure. Has zona pellucida.

Question 7

Blastocyst

Answer 7

Found in uterine lumen. Loses zona pellucida. Structure is 7 to 8 days old. Has inner cell mass, blastocoele cavity, and has a capsule.
Capsule is unique to mares and is made up of a glycoprotein structure.

Question 8

Expanded blastocyst

Answer 8

Day 7 structure. Can be seen with naked eye. Still has inner cell mass.

Question 9

UFO

Answer 9

Unfertilized oocyte. Compact football shape. Dark cells, clearly dead. Not expelled out of uterus, must be flushed to retrieve.

Question 10

Twins

Answer 10

Not well tolerated in mares. Recommended termination of one of the fetuses.

Question 11

Early embryo nutrition

Answer 11

Young embryo must be mobile for 17 days. Yolk sac depletes over time.

Question 12

Endometrial cups

Answer 12

Comes at day 37. Sticks around for 150 to 200 days. If pregnancy ends after day 37 then cup remains causing a pseudopregnancy.

Question 13

Relative maternal progesterone concentrations

Answer 13

image

Question 14

Placenta

Answer 14

Diffuse.
Epitheliochorial.
Non-deciduate.
Microplacentomes.

Question 15

Length of gestation

Answer 15

320-360 days

Question 16

Fetal maturation

Answer 16

Occurs in the last week of gestation. Cortisol rise in last 48 hours. Premature delivery is devastating due to this, lungs ect. are not ready till after cortisol rises.

Question 17

Colostrum

Answer 17

Has immunoglobulins. Foal has to receive in first 8 to 12 hours.

Question 18

Mammary secretion of electrolytes.

Answer 18

Changes correlated with fetal maturity. Ca> 40 mg/dl.

Increased K and decreased Na.

Question 19

Cervical dialtion

Answer 19

Occurs prior to parturition. Faster delivery. Improved neonatal adaptability.

Question 20

Stage 1 of parturition

Answer 20

1-4 hours.

Fetus (hopefully) changes position so feet and head face out.

Question 21

Stage 2 of parturition

Answer 21

30-60 mins.

Fetus expulsion.

Question 22

Stage 3 of parturition

Answer 22

Less than 3 hours.

Placental expulsion. If over 3 hours, considered retained. Can be an emergency.