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1

optimum sow

Gilt – age at first mating, - 8 monthd
Litter size - 14
Pre-weaning mortality <7 days
Weaning to farrowing 115 + 5 days
(Food efficiency)
Longevity - 6

2

pigs life cycle

Reach puberty ~ 140 days age, 120 kg
Mated on oestrus
Gestation 115 days
Lactate 4 weeks
Return to oestrus 5 days later
Culled after 6 parities
28 days until weanng

3

gilts - selection

Age
Weight
Oestrus
Disease status
Litter size
Vaccinal status

4

pregnancy diagnosis

Non-return to oestrus
Ultrasound real time, A-mode, Doppler
hormones
Visual

5

farrowing induction

prostaglandin
oxytocin

6

farrowing induction - advantages

management
fostering

7

farrowing induction - disadvantages

cost
risk of dates

8

litter size

Total born
Total born alive
Still births
Mummies
Parity changes

9

Weaning to oestrus interval

Oestrus detection
Duration of oestrus
Insemination/mating timing
Body weight loss
Cost of empty days

10

optimum mating time

sperm needed in the oviduct before ovulation

11

oestrus

lactation - 3 weeks
weaning to oestrus interval (WOI) - 6 days
oestrus - 48h
shorter WOI gives longer oestrus period

12

weaning to farrowing

Return rates – Regular/irregular returns
Abortions

13

longevity

culling rates
age at culling

14

diseases of gestation

abortion
smedi
vaginal prolapse

15

disease of peri-parturient period

Sow: uterine prolapse, Lactation. Agalactia, mastistis
Piglet Mortality.chilling, crushing, starvation

16

Non-infectious causes of abortion

Stockmanship/hygiene
Management policies i.e. age structure of the herd
Season (heat stress)

17

abortion - Specific Pathogens

Swine influenza
Porcine reproductive and respiratory
syndrome,
leptospirosis
Erysipelas
Uncommon but when they do occur they
cause severe reproductive disease.

18

Porcine Reproductive and Respiratory Syndrome.
“blue-eared” pig disease

Clinical signs:
Reproductive losses
increased pre-weaning mortality
severe respiratory effort in neonates (thumps)
Flu-like signs in older pigs
Blue extremities (25% die at 8% abortion/premature deaths
Economics - severe economic effects in acute phase, Chronic effects may include raised disease levels in grower pigs (immunosuppresive effects)

19

Porcine Reproductive and Respiratory Syndrome.
“blue-eared” pig disease - treatment

Supportive, treat secondary pathogens
Control: Originally notifiable, now reported
throughout the UK.
vaccinate

20

Leptospirosis. (L.bratislava)

Urine is the most common source of infection
Leptospires gain entry via mucous membranes
abortion and reproductive failiure
Risk factors; Rodents, Outdoor herds
Diagnosis - serology, dark ground microscopy, FAT
zoonotic

21

Leptospirosis. (L.bratislava) - treatment

Antibiotic medication: Streptomycin, Tetracyclines. In theory the whole herd should be treated at one time, this rarely happens.
Recent moves towards the use of cattle lepto vaccines in pigs

22

Laboratory investigations.

Sample at least three fetuses (and placenta if poss).
Stomach contents and /or liver. If taken aseptically may indicate opportunistic infections.

23

fetal fluid

Transplacental transfer of antibodies does not occur: Fetus is immunocompetant after 70d
Antibodies in fetal fluids (pleural or abdominal fluid)
indicate in utero challenge and are significant.
Test for - Parvovirus antibody, Leptospira bratislava antibody, Swine Influenza
can also do antigen detection

24

sow sampling

Positive titres.
May indicate the presence of disease within a
herd.
A significant rise in titre on paired serology may
indicate a recent infection.

25

VLA Porcine Abortion Kit - tests for

Swine influenza
Erysipelas
Parvovirus
PRRS
Leptospira

26

Variations in litters

Small number born (<6), embryos lost pre-ossification.
Mummified foetuses/stillbirths/weak pigs of all
one size. = uterine environment affected at one time
(stress, fever).
Mummified foetuses/stillbirths/weak pigs of differing sizes = prolonged damage to foetuses. Think infectious causes (commonly viral - parvo, PRRS, not forgetting……CSF etc)

27

Marker Stages of Gestation

35days: mummified fetuses through to stillborn piglets. (aborted at any stage).
70d Fetus immunocompetant
Full Term 112-116 days.

28

SMEDI

Stillbirth
Mummification
Embryonic Death
Infertility
porcine parvovirus most common cause

29

SMEDI - clinical signs

Full-term litter consisting of
small mummified fetuses
full grown stillborn
live weakly piglets
Rarely see abortion

30

parvovirus

93% of UK herds infected
Transmission - oronasal/venereal
If non-pregnant become immune
If pregnant (depends on stage of gestation) smedi