Normal and impaired postpartum uterine function in the cow

Question 1

Define puerperium.

Answer 1

Time from parturition until the complete uterine involution and resumption of regular oestrus cycles, with normal oestrous behaviour

also known as immediate postpartum period

Average duration of the postpartum period (PP) is 45 days.

Question 2

Most critical time in uterus point of view.

Answer 2

The puerperium.

Question 3

Describe normal uterine involution.

Answer 3

Significantly longer in pluriparous (40.6 days) than primiparous (34.0 days).

Average duration of the postpartum period (PP) is 45 days.

Diameter of the previously gravid horn usually halved by 5 days and its length halved by 15 days.

Whole uterus is usually palpable per rectum by 8 - 10 days.

Restoration of the endometrium: during the first 7 - 10 days PP there is noticeable loss of fluid and tissue debris (lochia). Should be gone by 18 days PP at the latest.

Question 4

The source of infection of the uterus is from

Answer 4

the environment.

Microorganisms ascend the genital tract at parturition and during the puerperium through the relaxed perineum, vulva and dilated cervix.

NB there are always exceptions

Question 5

Main driver of uterine involution?

Answer 5

PGF2 alpha

Massive release of PGF2alpha occurs during 2 - 3 weeks postpartum.

Question 6

How does uterine contamination with bacteria after parturition affect uterine involution?

Answer 6

The inflammatory process activates the arachidonic acid cascade and large amounts of PGF2alpha are formed which is an indicator of infectious process and cellular destruction of tissue.

Question 7

When does FSH secretion resume after parturition?

Answer 7

within 5-20 days

Prior to calving the high steroid production by the placenta suppress LH and FSH synthesis and content in the anterior
pituitary gland.

Question 8

The critical factor determing when the first ovulation takes place postpartum is

Answer 8

attainment of an LH pulse frequency similar to the follicular phase of the
cycle.

LH pulse frequency in the postpartum cow is regulated by nutrition, body condition score and suckling.

Question 9

Low LH pulse frequency postpartum causes

Answer 9

the first follicle to become atretic and a second dominant follicle develops.

Question 10

You left off at slide 23 (lecture left off way earlier)