Bovine Therio L1-4

Question 1

What is the average age of puberty in the Bovine?

Answer 1

10 months

Question 2

What is the Bovine’s Estrous cycle length?

Answer 2

18-24 d.

(21 d. avg)

Question 3

How many follicular waves does the Bovine have?

What is their duration?

Answer 3

• 2-3 waves
• lasting 7-10 d. each

Question 4

Which hormone dominates the

Follicular Phase of the Estrous Cycle?

Answer 4

LH

Question 5

What is the average duration of Estrus?

Answer 5

9 hrs

Question 6

Which hormone dominates

the Luteal Phase of Estrous?

Answer 6

Progesterone

Question 7

What coincides w/ the Estrogen peak

in the Follicular Phase?

Answer 7

Estrus

(standing to be mounted)

Question 8

When does Follicular Wave Emergence occur?

Answer 8

Pregnancy & Anestrus

Question 9

When does ovulation occur?

Answer 9

~ 24-30 hrs after the onset of estrus

Question 10

List the 2 PHASES of the Estrous cyle

& their duration.

Answer 10

• Follicular → d. 19 - estrus
• Luteal → d. 1 -18

Question 11

List the 4 STAGES of the Estrous Cycle

and their duration.

Answer 11

1. Estrus → d. 0
2. Metestrus → d. 1-3
3. Diestrus → d. 4-18
4. Proestrus → d. 19 until behavorial estrus occurs

Question 12

What stage of Estrous does ovulation occur?

Answer 12

Metestrus

Question 13

Characteristics of Metestrus?

Answer 13

• Final follicular maturation
• Ovulation
• Formation of the early CL → ability to secrete P₄

Question 14

When does the Luteal Phase of the Estrous Cycle begin?

How long does it last?

Answer 14

• Once significant concentrations of P₄ are observed in the perpherial blood
• Until the onset of Luteolysis (regression of the CL)