Porcine Flashcards
What is a stag?
Male castrated after puberty
What is a barrow?
Male castrated before puberty
What are 2 methods of castration?
Surgical
Immunological - Impravac GnRH vaccine
What is gestation length?
114-116d
What is the production aims for litters and pigs weaned/sow/year?
- 2 litters
10. 8 pigs weaned
What type of uterus do Sows have?
Bicornuate with highly developed uterine horns
How is the oestrus cycle described?
Non-seasonally polyoestrus
What type of ovulators are pigs?
Spontaneous
How long is the oestrus cycle?
21 days
When does puberty occur in sows?
5.5 months
What cycle are gilts first bred on?
3rd cycle
How many follicles undergo atresia?
40%
How long does proestrus last?
4-6 days
How long does oestrus last?
1-4 days
What hormone is not as significant in pigs as in polyovular species?
Inhibin
How long is dioestrus?
14 days
When does progesterone begin to rise?
2-4d after oestrus
Is the developing CL dependent on LH?
Not at the start
Until when is the CL resistant to PGF2a?
Until after day 12 of dioestrus -> maternal recognition of pregnancy occurs here (luteolysis will not occur and conceptus produces oestrogen)
What is the role of oestrogen produced by the conceptus?
To re-route PGF2a into the uterine lumen rather than circulation -> prevents luteolysis
How many piglets are required for MRP?
2 per horn
What type of placentation do pigs have?
Epitheliochorial diffuse (like horses)
2 methods of heat detection
- Expose to 10 mins boar contact daily
2. Back pressure test
when should we mate pigs?
24 hours before or 4 hours post ovulation for >90% conception
When do ova deteriorate?
4-6 hours post ovulation
What is the boar:sow ratio for pen mating?
1:8
Can we use frozen insemination in pigs?
No
How long is chilled semen stored for?
5 days
How many sperm and ml is an ejaculate?
200-300ml
30 billion sperm
What is a bactibag?
Nanopartical technology -> attracts bacteria to side and neutralises them
Heat seal ends
Keep at 15 degrees for fresh sperm
What should motility and morphology be?
Motility 70-80%
Morphology >75%
What should sperm be diluted to?
25-80 million sperm/ml
How much sperm is inseminated and where?
1 billion x days of storage
Cervix
When is rectal palpation possible?
27 days
When is doppler ultrasound viable?
29-34 days
What rate will the uterine artery and umbilical vein be?
uterine artery - 100-150bpm
Umbilical vein 150-200bpm
When can amnionic vesicles and the embryo be seen on real time ultrasound?
Amnionic vesicles 18-19d
Embryo with heartbeat 21d
What characterises the first stage or parturition?
Restlessness, nesting, rooting, pawing
Lateral recumbancy in last 60 minutes
What characterises 2nd stage parturition? How long between piglets?
Contractions, straining + piglet delivery
15 minutes between piglets
What characterises 3rd stage parturition?
Fetal membranes expelled between each or at the end of all
Retained fetal membranes are rare
What position should piglets be in?
Any position
at 6 hours after birth how much will the sows IgG concentration have dropped?
50%
When do piglets need an iron injection and how much?
within 5 days
200mg
What temperature shoudl piglets be at after birth?
> 30 degrees
List 3 pathogens causing reproductive wastage
- Porcine Parvovirus
- Leptospirosis
- Erysipelas
What is porcine parvovirus also known as?
Stillbirth, mummification, embryonic death and infertility syndrome (SMEDI)
What does SMEDI cause?
Depends on when she gets it
<30 d = EED
>30d = fetal death and mummification
>70d = fetus cant mount immune response
How is SMEDI transmitted?
Faecal-oral
How do we treat SMEDI?
No treatments - vaccinate over 6 months of age
How can we test for SMEDI?
Haemagluttination test
What does leptospirosis cause?
Abortion, stilbirths, weak piglets, infertility
How do we diagnose leptospirosis?
Microscopic agglutination test for rising antibody titre
How do we treat leptospirosis?
Vaccinate before breeding
Dry environment
Antibiotics (tetracyclines)
What does Erysipelas cause?
Fever, diamond shaped skin lesions, abortion, sudden death
Which disease is zoonotic?
Erysipelas
Leptospirosis
How do we treat erysipelas?
Penicillin
Vaccinate 6-8 weeks before breeding
When does seasonal infertility occur?
Late summer early autumn
What characterises seasonal infertility?
Reduced farrowing rate, failure of pregnancy maintenace and increased abortion and EED
How can we prevent seasonal infertility?
Maintain temp of 27 degrees
40-60% humidity best
What type of penis do males have?
Fibro-elastic
What accessory sex glands are present?
Prostate, seminal vesicles and bulbourethral gland
What type and orientation are the testis?
Non pendulous, caudal position
When do testis stop growing?
8 months
How long is spermatogenesis?
48-52 days
How long is epididymal transport time?
9-14 days
When do boars reach puberty?
5 months - mature at 8 months
What are 3 things that need to be done when introducing new breeding stock?
Introduction plan
Farm vaccination protocol
Gradual exposure to resident stock
What happens when boars are heat stressed?
Increased embryonic loss and reduced litter size
What are 3 breeding systems?
Pen mating
Hand mating
AI
How many boar:sow are needed for hand mating?
1:15
What is the ratio of boar:sow ratio for AI?
1:150
What improves litter size in AI?
Double sire mating system improves by 10-15%
How long does ejaculation take?
5 minutes - pressure associated
Describe the 3 sperm fractions
Pre-sperm (seminal plasma)
Sperm rich
Gel/sperm poor
Explain the gloved hand method
Guide to side collect in temperature controlled container + discard pre-sperm
Collect sperm rich fraction
Filter semen to remove gel fraction
What is the purpose of the two glove technique?
Prevent contamination from prepucial diverticulum that contains urine, semen, bacteria
Remove top glove and collect semen with clean glove
How do we measure semen concentration?
Haemocytometer
How do we measure motility?
Total progressive motility
What ratio is extender added to semen?
2:1
What is heterospermia?
Mixing sperm from 2-3 boars to increase piglets in litter
what are 3 disadvantages of AI?
Increase genetic bottle neck
Increased boar management
Good oestrus detection needed
What temperature is semen stored at?
15-18 degrees
What does boar saliva contain?
Pheromones
3a androstrenol
5a androstenone
What 4 things can cause non-infectious fertility?
Heat stress - decrease motility and sperm conc., pregnancy loss, EED
Vaccine - pyrexia following
Nutritional imbalances
Overuse of boars
How many times a day is a mature boar mated?
2
How long does oestrus itself last in sows?
2-3 days
At what size does a follicle start producing enough oestrogen to form behavioural oestrus?
4-7mm
What 4 things can be used to manipulate oestrus?
Progesterone (regumate)
PGF2a
PG600
Ovugel (triptoerlin acetate)
How do we use progesterone to manipulate oestrus?
6.8ml for 14d
4-9 days later in oestrus
what is PGF2a used for and in what dose?
Induce parturition - 10-15mg lutalyse or 175ug estrumate
Give on day 112-113 for farrowing 36 hours later
How is PG600 used?
Induce oestrus in gilts over 5.5 months old
How is ovugel used?
100mg triptorelin acetate GnRH agonist
Give sows 4 days post weaning intravaginally
Ovulate 48 hours later - fixed time AI 22 hours later
How long is the weaning to oestrus interval?
4-7 days
What does prolactin cause in pigs?
Lactational anoestrus
Interferes with GnRH pulses
When does ovulation occur and when should we inseminate?
Ovulation occurs 3/4 through oestrus (which lasts 2-3 days)
Inseminate within 12 hours prior to ovulation
Describe signs of psot mating uterine inflammation
Leukocytes in lumen of uterus remaining for 12-16 post insemination
List 3 methods for AI
Foam tip
Spiral tip catheter
Post cervical AI (hard to do)
When do embryos enter the uterus?
48-60 hours post ovulation
when does embryo attachment occur?
14-18 days
What are the 3 events of parturition?
Preparturient period -> restless nest building in last 24 hours
Intrapartum period -> farrowing
Postpartum period -> placenta passes
Name 2 complications in farrowing
Prolapsed vagina, uterus or bladder
Dystocia
How do we treat a pre-partum vaginal prolapse?
Replace and suture
How do we treat a uterine prolapse?
Laparotomy, amputation or manual reduction
How do we treat lateroflexion of the bladder?
Catheterize
What are clinical signs of dystocia?
Foul discharge, delay in farrowing, straining, no passage of placenta
What are 5 causes of dystocia?
- Uterine intertia
- Fetal maldisposition
- Obstruction of birth canal
- Deviation of uterus
- Fetopelvic disproportion
How do we treat primary uterine inertia? (animal does not start farrowing)
Prostaglandin
How can we give oxytocin for dystocia?
20-30 IU every 30 mins maximum 2-3 times
Always vaginal exam first to ensure it is clear
When do we use calcium for dystocia?
If oxytocin is not working
How do we give calcium for dystocia?
50-125ml warmed to body temperature, IV, IM, SQ,
No more than 25-30ml if going IM or SQ
What surgical treatment can be used for dystocia?
Terminal C section
What is a normal non-infectious abortion rate?
<2%
What is the name if an abortion syndrome and when does it occur?
Autumn abortion syndrome
30-110d post breeding
no clinical signs
What is a cause of non-infectious reproductive wastage?
Cystic follicles -> multiple of these cause extended anoestrus
Name 6 mycotoxins causing reproductive wastage
- Zearalenone
- Trichothecene
- Vomitoxin
- Ergot
- Aflatoxin
- Fumonisin
What does zearalenone cause?
Estrogen like substance - infertility, constant oestrus, reduced litter size, malformation
Disrupts sperm production and libido
