Transcript Improving piglet survival in large litters

Improving piglet survival
in large litters
Flemming Thorup
DVM, Ph. D.
Danish Pig Production
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Is lead by a board of pig producers
Secretariat
Breeding department (DAN bred)
Veterinary department
Dept. for Barn (equipment) and Production Systems
Department for Feeding and Reproduction
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Feeding of weaners and finishers
Reproduction
Quality of boar semen
AI techniques
Feeding of sows
Sow longevity
Female reproduction
Objects
• On farm investigations
• Large scale balanced comparative studies
• Observational studies
• Report writing
• Presentations
• Advisers, technicians, veterinarians, farmers, co-workers
• Information
• Teaching
• Vet. and anim. sci. students, graduation projects
• Handling general problems
• Herd problems
Improving piglet survival
in large litters
Production herd results
1992-2005
15
Number per litter
14
13
Total born
12
Live born
11
Weaned
10
9
8
1992
1994
1996
1998
Year
2000
2002
2004
Development 1992-2005
Year
1992
2005
Total born per litter
11,5
14,6
Still born, per cent
6
11
Piglet mortality, per cent
12
15
Weaned per sow
9,5
11
Per cent of piglets
Piglet age at death
4,5
4
3,5
3
2,5
2
1,5
1
0,5
0
15 per cent mortality
11 per cent mortality
0
5
10
15
20
Age at death
25
30
35
Most piglets die during the first 3-5
days
• Not much time to save the piglets
• - or
• Only 3 days of work to save the piglets?
Causes of mortality, percent of dead
Cause
Crushed
Sepsis
Small at birth
Starvation
Diarrhea
Hernia
Bleeding
Arthritis
Splayleg
Malformation
Miscellaneous
13 per cent
mortality
64
5
6
11
4
2
0
1
1
0
7
9 per cent
mortality
65
10
7
5
2
3
2
2
0
2
5
Primary diagnosis for crushed piglets?
Number of piglets
Autopsy
Herd 1
Herd 2
Coagulum in
ventricle
53
21
Empty ventricle
19
19
Causes of mortality
• Crushed-crushed-crushed and weak
• What comes first?
• Sepsis?
Mortality with increasing litter size
18
16
Per cent mortality
14
12
10
8
6
4
2
0
6
7
8
9
10
11
12
13
Live born piglets
14
15
16
17
18
Mortality per cent
Number at birth. Effect on mortality.
100
90
80
70
60
50
40
30
20
10
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18
Number at birth
Late born piglets have the highest
postnatal mortality
• Increase from 9-12
• No increase from 12 to 18?
• Late born piglets have to fight more for
milk (Barnes and Quainoo, IPVS 1982)
Antibody level and mortality
Ig 12 hours after birth
Per cent mortality
100
80
60
40
20
0
0
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85
Antibodies, gram/liter
Antibody level 12 hours after birth
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Average 45 g/liter
Large variations between piglets
0 at 12 hours = death
5 to 10 at 12 hours = hope for survivial
15 to 55 at 12 hours = fair chance
> 55 = will survive
• > 20 per cent of the piglets
Per cent of live born piglets
Distribution of birth weights
12
10
8
6
4
2
0
0,3
0,5
0,7
0,9
1,1
1,3
1,5
1,7
Birth weight, kg
1,9
2,1
2,3
2,5
Mortality, per cent.
Weight at birth and mortality
80
70
60
50
40
30
20
10
0
4,5 per cent
6,0 per cent
2,5 per cent
13,0 per cent
0,5
0,7
0,9
1,1
1,3
1,5
Birth weight, kg
1,7
1,9
2,1
2,3
Per cent underweight
piglets
Underweight piglets and litter size
25
20
15
10
5
0
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21
Number of total born piglets
Piglet mortality
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The piglets die by crushing
- during the first days
They are the smallest piglets
They are the last born piglets
They are the piglets with a low antibody intake
• Piglets going to be crushed can be predicted at
birth
• Piglets that are going to survive can be predicted
at birth
• Most piglets are in between!
Effect of birth weight and birth order
on mortality
< 1 kg
≥ 1 kg
Number of piglets
29
173
Mortality, per cent
45
5
Birth weight
Effect of birth weight and birth order
on mortality
< 1 kg
≥ 1 kg
Number of piglets
29
173
Mortality, per cent
45
5
Birth weight
Birth order
1-7 > 7 1-7 > 7
Number of piglets
13
16 101 72
Mortality, per cent
8
75
3
8
Birth weight, birth order and Ig
Birth weight
<1 kilo
≥ 1 kg
No. at birth
1-7
>7
1-7
>7
Piglets, no.
13
14
99
71
Deaths, no.
1
10
3
5
Low Ig, no.
0
4
1
3
Low Ig means < 10 gram/liter. (Average = 45 gram/liter)
Hypotheses for piglets born in large
litters
• The first born piglets have readily access to
colostrum and milk
• The last born piglets must compete with
the fortunate first born piglets
• The smallest piglets loose this competition
Solution
• Litter size must be adjusted
• Moving piglets to small litters
• Using nurse sows
• When?
• After colostrum uptake
• Before the piglets die
• Before ranking
Colostrum uptake
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Registration of birth order and birth weight
Assay 12, 24 and 48 hours after birth
Assay for non specific Ig’s
Registration of mortality until weaning
Ig after 12 hours (mg/ml)
Effect of birth order
100
90
80
70
60
50
40
30
20
10
0
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19
Birth order
Ig after 12 hours (mg/ml)
Effect of birth weight
100
90
80
70
60
50
40
30
20
10
0
0,0
0,5
1,0
1,5
Weight, kilo
2,0
2,5
3,0
What is the optimal nurse sow for 12
hours old piglets?
• Parity
• A second to fourth litter sow have the highest milk production
• Stage of lactation
• Milk composition
• Increasing or decreasing production
• Empty period
• Milk pressure, motivation or forgetting her own piglets?
• Accept of piglets
• Relaxants
• Oxytocin
One step nurse sow
21 day old piglets
New born piglets
Two step nurse
7 day old piglets
New born piglets
21 day
old piglets
One or two step nurse?
One step nurse Two step nurse
21 day lactation 7 day lactation
Available
Easy
More work
Double risk
Acceptance of
new piglets
???
???
Milk production
Decreasing
Increasing
Milk quality
High
High
Set up of trial
• Collecting pairs of newborn piglets after
colostrum-uptake
• All piglets were earmarked and weighed
• One piglet stayed with the mother
• One piglet went into the trial
Nurse sows
• Piglets randomly entered a one step or a two step
nurse sow
• All nurse sows were 1. Litter sows
• Both nurse sows had an equal profile
• Number of piglets born
• Number of piglets weaned
• Lactation length
• Video for 24 hours
• Mortality and weight at weaning was recorded
Results
One step nurse
Two step nurse
Litters
10
10
Piglets
110
110
7
5
18a
6b
5,5a
6,4b
Hours to first
nursing
Mortality, %
Weaning
weight, kg
Results
Control piglets One step
nurse
Two step
nurse
Litters
201
10
10
Piglets
220
110
110
(40 minutes)
7
5
6b
18a
6b
6,3b
5,5a
6,4b
Hours to first
nursing
Mortality, %
Weaning
weight, kg
Two step nurse
7 day old piglets
New born piglets
21 day
old piglets
The first step piglets
• Piglets earmarked and weighed at transfer
at 7 days and at weaning
• Compared with a similar litter not
transferred
Transferred two step nurse piglets
Transferred
piglets
Piglets not
transferred
Litters
10
10
Piglets
119
116
7,2
6,1
2,2
2,3
Mortality, %
3,4
6
Weaning weight, kg
6,3
6,7
Age at
transfer/control
Weight at
transfer/control
Gilts or sows as nurse sows
1. Litter sows
2.-5. Litter sows
Litters
12
12
Piglets
124
126
Mortality, %
12a
28b
Weaning
weight, kg
6,9
7,1
Dead piglets, No.
Piglet mortality at first litter or older
nurse sows.
10
9
8
7
6
5
4
3
2
1
0
1. litter
> 1 litter
1 2 3 4 5 6 7 8 9 10 11 12
Pair
11 or 13 piglets per litter?
• 31 pairs of sows with 24 piglets
• Piglets were app. 24 hours old
• 11 and 13 piglets were allocated to the two
sows
• No transfer of piglets after allocation
• Piglets at both sows were weaned at the
same day
11 or 13 piglets per litter?
Litter size
11
13
Litters
31
31
Mortality
8,2*
10,2*
Weight per
piglet
7,7a
7,1b
Piglets weaned
313
363
* P = 0,08
Trial
Ensuring colostrum to the smallest piglets
• Control
• Adjusting litter size
after 12 hours
• Small or large piglets
could be transferred
• Trial
• Reducing litter size to
10 after 6 hours by
removal of the largest
piglets
• Adjusting litter size
after 12 hours
• Small or large piglets
could be transferred
Ensuring milk to the smallest piglets
Control
Size
Weight in
kilo
Small
Large
0,5 -1 1,1-2,4
Trial
Small
0,5 -1
Isolated
part of
1,1-2,4 ”large”
Large
Number
64
414
74
419
161
Mortality
28*
10
34*
8
7
34
22
15
34
68
Transferred
* A difference of 15 per cent would be significant.
Ensuring milk to the smallest piglets
• No effect on the survival of the smallest
piglets, when reducing the litter to 10, to
ensure colostrum to the smallest piglets .
• Were there an effect of removing
(collecting) the smallest piglets?
• Is mortality in small piglets primarily a
cause of lack of sows milk?
• Large piglets may be removed from the
mother after 6 hours
Conclusions
• Crushing may be the visible cause of death,
but a number of precursors seems to exist
• Understanding these precursors may lead
into ways of reducing piglet mortality
• A number of other management factors
have been shown to reduce piglet
mortality, eg. observation during and after
birth, drying off small piglets, climate
control, vaccinations and treatments of
disease. Intensive daily care must be
continued, when introducing new
strategies in the farrowing department.
Ekstra
Underweight piglets
• Undernourished during pregnancy (IPVS)
• Heat loss after birth (Hoy, …).
• Better survival when small piglets were
collected at a nurse sow. (Straw et al.
1998)
Body temperature with and without drying of the
piglets. Hoy, 2003?
Rectal temperature (°C)
p < 0,01
Minutes after birth
40
39
38
37
36
35
0
15
30
45
60
Without
n = 117
90
120
With drying
n = 52
Routes of newborn to first uddercontact (Bünger 1983)
Main routes
Most frequent
routes of mistakes
A two step nurse is the nurse sow at choice
7 days old piglets
New born piglets
21 day
old piglets
Per cent survival
Survival by litter size
Overvejes, kun pct. levf.
100
90
80
70
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Total born piglets in the litter
0,3
0,4
0,6
0,7
0,8
0,9
1
1,1
1,2
1,3
1,4
1,5
1,6
1,7
1,8
1,9
2
2,1
2,2
2,3
2,4
2,5
2,6
Dødelighed (%)
100
90
80
70
60
50
40
30
20
10
0
Fødselsvægt / kg
Effect of birth number
50
Ig konc. (mg/ml)
45
40
No. 1-7
35
No. 8-12
No. 13-18
30
25
20
Ig 12t
Ig 24t
Ig 48t
No. Piglets at 12h
Effekt of IGG on mortality
45
40
35
30
25
20
15
10
5
0
0
10
20
30
40
50
60
Ig konc. at 12 hours
Total antal grise
Total antal døde
70
80
Per cent survival
Birth weight versus piglet survival
100
90
80
70
60
50
40
30
20
10
0
13 per cent mort.
9 per cent mort.
0,5
1
1,5
Weight at birth
2
Liveborn piglets with increasing litter
size
Live born, No.
20
15
10
5
0
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21
Total born, No.
Colostrum intake by birth weight
50
Ig konc. (mg/ml)
45
40
< 1 kg
35
1-2 kg
> 2 kg
30
25
20
Ig 12t
Ig 24t
Ig 48t
Colostrum intake by birth order
50
Ig konc. (mg/ml)
45
40
Nr. 1-7
35
Nr. 8-12
Nr. 13-18
30
25
20
Ig 12t
Ig 24t
Ig 48t
Ig-gram per liter colostrum
Ig in colostrum after birth
200
150
Sonr_1
100
Sonr_2
50
Sonr_3
0
0
10
20
30
40
50
60
Hours after first piglet
70
No. weaned piglets
No. weaned piglets when increasing
total born piglets
15
13
11
9
7
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21
No. total born piglets per litter