Puberty

Puberty

“process” of acquiring reproductive competence

When does puberty start in the female?

Age at first estrus

Puberty is NOT

sexual maturity

When does puberty start in the male?

Age when the ejaculate contains a threshold number of sperm.

At what age do bovines typically reach puberty?

11 months

Before puberty, GnRH levels are

low

What happens in the hypothalamus in females after puberty begin?

Surge center releases GnRH during preovulatory stage 

What happens to hypothalamic sensitivity once puberty begins?

Hypothalamic sensitivity decreases to testosterone and estrogen.

What are the steps of the LH surge in females at the start of puberty?

1. 1st LH Surge

2. “Silent” Ovulatio/2nd LH Surge

3. First Estrus

What is the fundamental requirement for onset of puberty?

Secretion of GnRH to stimulate gonadotropin release from anterior pituitary. 

What are some factors that can impact puberty?

• Genetics

• Nutritional Status

• Environment (season)

• Social cues (presence of a bull)

• Degree of fat cells in females

What are the changing features in Peripuberal Bulls

• Increased aggressiveness and sexual desire

• Growth of penis and testicles

• Separation of penis from prepuce.