Mare & Ewe Reproductive Cycle

Question 1

What term would you use to describe the Ewe oestrus?

Answer 1

Seasonally Polyoestrus

Question 2

What term would you use to describe the Mare oestrus?

Answer 2

Seasonally Polyoestrus

Question 3

What 3 factors influence the mare to come in to season?

Answer 3

Longer hours of day light
Warmer days
Improved grass quality
(eg. April (spring) - July (mid-summer))

Question 4

What are the basic stages of Oestrus?

Answer 4

Pro-oestrus - “Building up” phase. LH, FSH & oestrogen produced.
Oestrus - Sexual receptivity. Oestrogen high, some progesterone. Surge of LH results in rupture of follicle & release of Ovum.
Met-oestrus - Formation of Corpus Luteum which releases progesterone & promotes pregnancy.
Di-oestrus - short period of inactivity after met-oestrus before returning to pro-oestrus (in polyoestrus animals).
Anoestrus - no sexual/hormonal activity between seasons.

Question 5

Age of puberty?

Answer 5

Mare = 18 months
Ewe = 8 months

Question 6

Age at first mating?

Answer 6

Mare = 2-4 years
Ewe = 1-1.5 years

Question 7

Length of Oestrus cycle?

Answer 7

Mare = 21 days
Ewe = 17 days

Question 8

Length of Oestrus?

Answer 8

Mare = 6 days
Ewe = 1-2 days

Question 9

Gestation?

Answer 9

Mare = 11 months
Ewe = 5 months

Question 10

Ovulations per cycle?

Answer 10

Mare = 1
Ewe = 2-3

Question 11

Factors influencing ewe to come in to season?

Answer 11

Climate & area of country