The Estrous Cycle in Cattle Physiology and Endocrinology

These flashcards cover key terms and concepts from the lecture on the estrous cycle in cattle physiology and endocrinology.

Follicular Wave

A wave-like pattern of follicle development in the estrous cycle, consisting of recruitment, selection, growth, dominance, and regression.

Follicle Stimulating Hormone (FSH)

A hormone that precedes recruitment of follicles and is used for superovulation and embryo transfer in cattle.

Luteinizing Hormone (LH)

A hormone that promotes further follicle growth and maturation of eggs during the estrous cycle.

Estrogen

A hormone produced by growing follicles that causes estrus and triggers the LH surge for ovulation.

Corpus Luteum (CL)

Formed from the ovulated follicle and produces progesterone, responsible for maintaining pregnancy.

Prostaglandin F2a (PG)

A hormone produced by the uterus late in the estrous cycle that causes regression of the corpus luteum.

Estrus

The phase in the estrous cycle characterized by the female's willingness to mate.

Progesterone

A hormone produced by the corpus luteum that maintains pregnancy after conception.

Ovulation

The release of an egg from the follicle during the estrous cycle, triggered by the LH surge.

Estrous Cycle Length

Typically 18 to 24 days in cattle, depending on the number of follicular waves (2 to 3).

Hormonal Relationships

The interactions among estrogen, progesterone, and PG during the estrous cycle.

Superovulation

A technique involving FSH to induce the growth of multiple follicles for embryo transfer.

LH Surge

A rapid increase in luteinizing hormone that triggers ovulation.

Embryo Blockade

The presence of an embryo prevents the uterus from producing PG, maintaining the corpus luteum.