1
Q
Sows
A
Female pigs that have had piglets
2
Q
Gilts
A
Female pigs that haven’t had piglets
3
Q
Pig uterus
A
- bicornuate
- long horns
- short body
4
Q
Oocyte production
A
15-30 oocytes per estrus
5
Q
Puberty
A
150-220 days old
6
Q
First AI
A
2nd or 3rd estrus cycle
7
Q
Gestation
A
- 3 mos, 3 wks, 3 days (113-155 days)
- avg is 115 days
8
Q
Lactation anestrus
A
16-40 days
9
Q
Weaning to estrus
A
4-6 days
10
Q
Estrous cycle
A
18-24 days
11
Q
Estrous phase
A
4-6 days
12
Q
Luteal phase
A
15 days
13
Q
Time from estrous to ovulation
A
36-44 hrs
14
Q
Duration of estrous w/o boar
A
<24 hrs to >96 hrs
15
Q
Duration of estrous in presence of boar
A
40-60 hours
16
Q
Placentation type
A
Epitheliochorial
17
Q
Follicular phase events
A
- estrogen increases as oocyte & follicle mature to ovulation
18
Q
Proestrus events
A
- E2 and FSH increase to prep for estrus
- some LH released
19
Q
Estrus events
A
- oocyte is mature
- E2, FSH,& LH increase -> rupture of follicle & ovulation
20
Q
Luteal phase events
A
- progesterone increases due to CL development
21
Q
Metestrus events
A
- E2, LH, & FSH decrease
- female isn’t receptive to male
- follicles begin luteinization -> corpus hemorrhagicum -> CL
- CL secretes progesterone
22
Q
Diesstrus events
A
- longest stage of estrous cycle
- progesterone increases around day 12-15
- if no oocyte detected by day 15 -> PGF2a causes C to regress and reduce progesterone secretion
23
Q
If a pig is mounting a pig that is in heat, then…
A
It is coming into heat
24
Q
If a pig is standing and allowing you to do whatever you want, then…
A
It is in heat
25
Standing heat
- 12 hrs after 1st AI
- 12 hrs after 2nd AI
- Ovulation & fertilization
26
How does suckling suppress LH
Inhibits GnRH from hypothalamus which prevents follicular wave from being produced
27
Days to allow uterus to involute
21-28
28
Weaning piglets too early can cause
- decreased FSH and LH -> follicular cyst development
29
Follicular cysts
Follicles grow, no ovulation bc LH too low
30
Hormone that stimulates ovulation
HCG
31
PG 600 (400 IU eCG & 200 IU hCG)
- Induces puberty
- come into estrus 7 days post-inject.
32
Altrenogest (Matrix)
- synchronizes estrus
- inhibits follicular growth until removed from circulation, then all follicles grow & ovulate @ same time
