An overview of swine reproduction

2. THE FEMALE
 Oviducts: 15- 25 cm
 Uterus: Bicornuate
Cornua: 60- 90 cm
 Cervix:
• Diameter: 2. 5 cm
Length: 15- 20 cm
• 5 interdigitating pads- Locking mechanism for penis
• Source of mucus

3. THE FEMALE
 Vagina: 30. 5- 45 cm
• IgA
• pH: Acidic
• Bladder empties 5 cm from external orifice
• Clitoris

4. THE FEMALE
The female reproductive system Cervix- Interdigitating pads

5. THE MALE
 Scrotum: Close to body wall
2 ºC lower
 Testes: Upside down
 Epididymis: ~58 m when stretched
 Penis:
• Fibroelastic
• S- shaped when not stimulated
Corkscrew shaped when stimulated

6. THE MALE
B
The Penis
A- Non erectile/ S- shaped
B- Erectile/ Corkscrew shaped

7. THE MALE
 Preputial divertivulum: Above prepuce
Collects urine and sloughed cells
Odourous
Could contaminate ejaculate
 Muscle under voluntary control regulates urination and
prevention of contamination of semen during ejaculation
Diverticulum
Opening into
prepuce

8. PUBERTY
 Females: Around 5 months
Breeding age- 6 months (Preferably those
with 14 teats)
 Males: Around 5 ½ months
Breeding age: 18 months

9. THE OESTROUS CYCLE
 Polyoestrus
 18- 24 days (~21 days)
Oestrus period: Gilts: 1.5- 2 days
Sows: ≥ 2- 3 days
 Follicular phase: ~5 days
Luteal phase: ~16 days
 Ovulation: Mid- late oestrum
~15- 24 ova over 1- 4 hours
Ovulation rate increases over 1st 4 cycles

10. SIGNS OF HEAT
 Behavioral signs:
• Fence walking
• Vocalizing
• Kyphosis
• Mounting
• Standing heat
 Physical signs:
• Vulva- Swells and
reddens
• Vaginal discharge
Standing heat: Rub her flanks, scratch her back and apply
pressure on her loins. A positive response is when she stands
”locked- up”. Her ears may additionally perk and her tail may
switch to expose the vulva.

11. SIGNS OF HEAT
Swollen and red vulva
of gilt
Red interior of vulva
of sow
Clear, sticky mucus
“Thumb checking”

12. SIGNS OF HEAT
Standing heat

13. SIGNS OF HEAT
✓ Nose- to- nose exposure to a boar enhances breeding
success
Commercial aerosol spray that mimics
boar odor

14. BREEDING
1. Pen mating
2. Hand mating
3. AI
1. Pen Mating: Boar- to- sow → 1: 15 to 1: 25 (Average → 1: 17 or 1: 18)

15. BREEDING
2. Hand Mating:
• Female is mated 2- 3 times (1st mating on Day. 1 of
standing heat, subsequent matings at 24 hour
intervals)
• Using different boars may increase the litter size
• Boar ≤ 2 matings/ day

16. BREEDING
3. AI:
• Gilts: 1st insemination: 8- 12 hours after standing heat onset
2nd insemination: 12- 16 hours later
Sows: 1st insemination: 24 hours after standing heat onset
2nd insemination: 18- 24 hours later
• Single sire semen → Breeding or show animals
Pooled semen → Market pigs
CHARACTERISITC EJACULATE EXTENDED SEMEN
Volume (ml) 100- 500 ≥ 70
Concentration (106/ ml) 100- 200 25- 65

17. BREEDING
Spiral catheter Position of catheter in
cervix
Administration of semen

18. PREGNANCY
 Ova: Survive for 8 - 12 hours
Reach ampulla in 30 minutes - 1 hour
 Sperms: Deposited in cervico- uterine junction
Ability to fertilize decreases after 24 hours
Most reach ova in 3- 6 hours. Number ↑ for
up to 12 hours.

19. PREGNANCY
DAY OF GESTATION EVENT
Day. 1 (2- 6 hours) Fertilization
Day. 2 - 2 ½ Embryos enter uterus
Day. 10 - 14
Maternal recognition
Intrauterine migration
Day. 13 - 40 Implantation
Day. 35 Skeletal mineralization
Day. 70 - 75 Immunocompetence
Gestation length: 114 ± 2 days

20. PREGNANCY
 Embryonic death after Day. 35 → Expulsion or Retention
 Embryonic loss- Greatest < Day. 30
 To increase colostral antibodies, immunize during last 6
weeks
Fertility: 95%
Embryonic mortality: 30
- 40%
Litter size: 10 - 16

21. PREGNANCY DIAGNOSIS
1. Oestrus detection
2. Rectal palpation:
i. Cervix- Tone, tension
ii. Uterus- Weight, contents
iii. Fremitus

22. PREGNANCY DIAGNOSIS
3. Ultrasonography:
TYPE OBSERVATIONS FALSE POSITIVE FALSE NEGATIVE
A- Mode Fluid accumulation in uterus • Bladder
• Pseudopregnancy
• Pathological fluid
accumulations
• < Day. 28
• > Day. 80
Doppler Uterine a.: 50- 100 bpm
Umblical a.: 150- 250 bpm
Fetal heart rate: 100- 150 bpm
• Oestrus
• Pseudopregnancy
• Metritis
• < Day. 29
B- Mode • Pockets of fluids
• Fetal heart activity
• Skeleton
• < Day. 21

23. PREGNANCY DIAGNOSIS
A- Mode Doppler
B- Mode

24. PREGNANCY DIAGNOSIS
Day. 28 Day. 35- 40 Day. 70

25. PREGNANCY DIAGNOSIS
4. Radiography
5. Oestrone sulphate concentrations:
• > 0.5 ng/ ml
• False positive: In the process of return to oestrus
False negative: ≤ 4 piglets
• Concentration during Day. 70- 80 ⍺ Litter size
4. PGF2⍺ concentrations: < 200 pg/ ml

26. PREGNANCY DIAGNOSIS
5. Progesterone concentrations: > 5 ng/ ml
6. Vaginal biopsy: 2- 3 layers of stratified squamous
epithelium in vaginal wall

27. PREGNANCY DIAGNOSIS
TECHNIQUE PERIOD OF EFFECTIVITY
Oestrus detection Any time
Rectal Palpation > Day. 30
Ultrasonography
A- Mode Day. 28- 80
Doppler > Day. 29
B- Mode > Day. 21
Radiography > Day. 35
Oestrone sulphate estimation Day. 25- 30, > Day. 80
PGF2⍺ estimation Day. 13- 15
Progesterone estimation Day. 17- 20
Vaginal biopsy Day. 30- 90

28. FARROWING
Signs of approaching farrowing:
 Restlessness
 Nest building
 Mammary glands- turgid
 Mammary secretion: Serous → Milk
 Blood stained vaginal discharge 1- 2 hours beforehand
 Small greenish pellets from vagina → piglet in an hour

29. FARROWING
Vulva prior to farrowing

30. FARROWING
Initiation:
↑ Cortisol → PGF2⍺ release
Oxytocin → Uterine contractions
 Piglets are delivered in 10 – 15 minute intervals (5 – 45 minutes)
 Fetal membranes expelled in 4 hours
Luteolysis
Relaxin release → Relaxation of cervix and birth canal

31. FARROWING
Diffused placenta

32. FARROWING
 Any increase in the time interval between piglets
increases chances of injury or death in the uterus
 Cranial and caudal presentation
 Inj. Oxytocin @ 10 – 30 IU for assistance
 Dystocia incidence: 1 – 2%
Mostly due to uterine inertia
Inj. Oxytocin @ 20- 30 IU every 30 minutes, 3 times
Inj. Calcium for uterine inertia

33. FARROWING
Induction:
 PGF2⍺ : 72 hours of expected farrowing date
Farrowing in mostly 22- 32 hours
Slightly premature piglets → Good environment for survival
 Oxytocin: 15- 24 hours after PGF2⍺
Quickens farrowing but may cause dystocias

34. POST PARTUM
 Lactational anoestrum ← Suckling reflex
21 days for complete uterine involution
 Return to heat after weaning in 4 - 7 days
 Induction of oestrus: Split weaning
Removing all piglets for a few hours for 3 – 4
consequtive days
Gonadotropin treatment
Weaning age: Primiparous: 14 - 16 days
Pluriparous: 9 – 11 days

35. REFERENCES
 Breeding Management in Pigs- Gary C. Althouse et al.
 Reproductive Physiology and Anatomy of the Sow- Dr. Wayne Singleton
and Dr. Mark Diekman
 Pregnancy Diagnosis in Sows and Gilts- Gordon King
 Evaluating Boar Semen Quality- Dr. Kevin J. Rozeboom
 Pregnancy Diagnosis- A Brief Review- Glen W. Almond
 www.livestocktrail.illinois.edu/swinerepronet/paperDisplay.cfm?ContentID
=6274
 www.livestocktrail.illinois.edu/swinerepronet/paperDisplay.cfm?ContentID
=6273
 www.fao.org/docrep/t0690e/t0690e06.htm
 https://extension.psu.edu/courses/swine/reproduction/breeding-
management/cycles-and-heat-determination
 www.cal.vet.upenn.edu/projects/swine/bio/fem/estr/hm.html
 www.unipr.it
 www.porkgateway.org/resource/pregnancy-diagnosis-in-swine/