ANSC 4045 Chapter : Basic Parameters Of Reproduction
1. There is no period of sexual receptivity in women. Ovulation will occur approximately 14 days after the beginning of menses.
2. The placenta of the bovine and ovine is classified as epitheliochorial but is sometimes termed syndesmochorial because of a
transient erosion and regrowth of the endometrial epithelium.
3. The gestation length of the pig is often stated as three months, three weeks and three days.
Basic Parameters of Reproduction for Domestic Species and the Human
Species Type of
Cycle
Cycle
Length
Duration of
Estrus
Interval from
Beginning of
Estrus to
Ovulation
Interval from
Ovulation to
Maternal
Recognition
of
Pregnancy
Interval from
Ovulation to
Initial
Uterine
Attachment
Type of
Placentation
Length of
Gestation
Bovine Poly Estrus 21 days 15h 24-32h 15-16 days 18-22 days Cotyledonary
Epitheliochorial2
9 months
(282 days)
Ovine Seasonal
Poly Estrus 17 days 30h 24-30h 13-14 days 15-18 days Cotyledonary
Epitheliochorial2
5 months
(150 days)
Porcine Poly Estrus 21 days 50h 36-44h 11-12 days 14-18 days Diffuse
Epitheliochorial
3.8 months3
(115 days)
Equine Seasonal
Poly Estrus 21 days 7 days 5 days 12-14 days 36-38 days Diffuse
Epitheliochorial
11 months
(336 days)
Human Menstrual 28 days NA1 NA1 7-12 days 9-12 days Discoid
Hemochorial 9 months
