Transcript Echografie als diagnostisch hulpmiddel bij

Department of Animal Science
Wageningen University
Adaptation Physiology
Aquaculture and Fisheries
Breeding and genetics
Cell Biology and Immunology
Nutrition
Experimental Zoology
Intermittent suckling: possibilities to establish
pregnancy during lactation & benefits to piglets
Marieke Berkeveld
Rosemarijn Gerritsen
Pieter Langendijk
In cooperation with Veterinary Faculty in Utrecht
Weaning-induced growth check
weaning
600
g/day
400
200
0
-200
7
14
21
28
35
days pp
after Weary et al., 2002
42
49
Feed intake shortly after weaning
Many piglets hardly eat after weaning
Bruininx et al., 2002
Weaning related problems, due to
• age at weaning
• not familiar with dry feed
•…
Possible solution:
Make pigs familiar with dry feed before weaning
Intermittent
suckling:
Suckling inhibited
for 12 h per day from
D14 of lactation
feed intake post weaning, g
Feed intake before and after weaning
4000
control
3500
IS
3000
2500
2000
1500
1000
500
0
0
500
1000
1500
2000
total feed intake during lactation, g
Eat before weaning = eat after weaning
Kuller et al., 2000
feed intake post weaning, g
Feed intake before and after weaning
4000
control
3500
IS
3000
2500
2000
1500
1000
500
0
0
500
1000
1500
total feed intake during lactation, g
Kuller et al., 2000
2000
Distribution of feed intake during lactation
45
number of litters
40
control
35
IS
30
25
20
15
10
5
0
0-250
250-500 500-750
7501000
10001250
>1250
feed intake during lactation, g
Intermittent suckling increases feed intake during
lactation
Kuller et al., 2000
Intermittent suckling increases feed intake during lactation,
But weaning at conventional age still induces a growth check
Possible solution:
Also extend lactation
without postponing next pregnancy
Growth in the IS model
a
250
200
b
IS1 2
1000
weani ng I S
a
CW
ADG, g /p i g l e t
300
IS1 2
weani ng CW
350
st art I S
A D G, g/ pi gl et
CW
800
600
b
b
150
400
b
a
100
200
a
50
0
0
13
16
20
23
27
Day of experiment
34
41
W
W2
W6
55
Day of experiment
Feed intake in the IS model
200
a
weani ng IS
300
ADF I, g /p ig let
weani ng convent i onal
IS D1 4
st art T S
ADF I, g /p ig let
wea n D2 1
1400
1200
a
1000
b
800
b
a
600
100
a
400
b
b
b
200
a
0
0
13
16
20
23
27
34
day
41
W
W2
W6
55
day
Relative growth from milk and dry feed
Growth from milk or feed intake (IS 12)
gr ow t h f r om m i l k
gr ow t h f r om f eed
% o f g ro wth
100
80
60
40
20
0
23
27
34
41
W
day of exper im ent
Conclusions
Intermittent suckling results in better adaptation to weaning:
• Feed intake at weaning is considerably higher than normally
• There is hardly any growth check at weaning
• If sow is mated, lactation can be extended
Consequences for reproduction ?
Past experience with IS
Source
Stage of
lactation
h
IS/day
Boar
Sows in
contact? estrus
Crighton, 1970
D21-D31
12
yes
1/5
Stevenson and Davis, 1984
D14-D28
D14-D28
6
12
no
no
13/20
5/10
Grinwich and McKay, 1985
D21-D35
D21-D35
3
22
yes
yes
<10%
±80%
Newton et al., 1987a
D13-D20
D13-D20
D13-D20
D13-D20
3
6
6
6
yes
yes
yes
no
13/30
15/19
5/28
4/28
Newton et al., 1987b
D20-D28
6
yes
10/10
Kuller et al., 2004
D16-D27
12
no
11/49
Past experience with IS
• Litter separation
– Number of sows with estrus: VARIABLE
– Occurrence of estrus: ASYNCHRONISED
• Important factors
– Stage of lactation
– Duration of separation
– Boar contact
– Parity
– Breed
– …
Intermittent suckling model
Intermittent suckling from
D14 (or later) of lactation:
Suckling inhibited for 12 h:
IS12: 0800-2000
IS6: 0800-1400 and 2000-0200
Weaning at 6 w of lactation
Reference: continuous
lactation and weaning at 21 d
Dalland sows
LH secretion during IS regime
START IS
614 B LO D6.5
LH
(ng/ml)
2
1.8
Day 1
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
20:00
period of suckling
8:00
20:00
4:00
Cortisol secretion during IS regime
Total separation more effective
TOTSEP N=6
in triggering
LH release and
PHYSEP N=5
increased
sow 614chance of estrus
70
60
*
*
Cortisol (ng/ml)
50
*
*
40
30
20
10
0
9
11-15
D1
21-3
9
11-15
D2
21-3
9
11-15
21-3
9
D3
TOTSEP: sows taken away from farrowing unit
PHYSEP: sows only separated physically from piglets
*treatment effect
11-15
D4
21-3
Estrus and ovulation
C
IS12
IS6
# sows in exp start
IS/weaning
23
14
13
lactational oestrus
(%)
26%
100%
92%
oestrus after
weaning (%)
74%
-
-
ovulation (%)
100%
93%
83%
cystic follicles
0
1
4*
*2 of 4 sows ovulated and developed cystic follicles
Follicle development during IS regime
9
8
7
size (mm)
6
C
5
IS12
4
IS6
3
2
1
0
-1
0
1
2
3
scanday
4
5
6
40
7
35
6
30
25
5
20
4
15
10
3
5
0
-60 -36
-12
12
36
60
84
Time from LH surge, h
2
108 132
Oestradiol
LH
Oestradiol, Progesterone
Peri-ovulatory endocrine changes
Progesterone
LH
Estradiol
C (n=16)
40
IS12 (n=12)
IS6 (n=7)
estradiol
(pg/ml)
30
20
10
0
-40
-30
-20
-10
0
10
Time relative to LH surge (h)
20
30
Pre-ovulatory LH surge
*
10
C (n=16)
9
IS12 (n=12)
8
IS6 (n=7)
LH
(ng/ml)
7
6
5
4
3
2
1
0
-40
-30
-20
-10
0
10
Time relative to LH surge (h)
20
30
40
Post-ovulatory progesterone rise
C (n=12)
progesterone
(ng/ml)
30
*
25
*
*
*
IS12 (n=11)
*
IS6 (n=7)
20
15
10
5
0
-20
0
20
40
60
80
Time relative to ovulation (h)
100
120
Estradiol concentration (pg/ml)
30
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
25
20
15
10
5
0
-75 -69 -63 -57 -51 -45 -39 -33 -27 -21 -15 -9 -3
3
9 15 21 27 39 51 63 75 87 99
Time relative to ovulation (h)
sow 3 oestradiol
sow 19 oestradiol
sow 3 LH
sow 3 progesterone
sow 19 LH
sow 19 progesterone
LH and progesterone
concentration (ng/ml)
Cystic sows
• LH surge and progesterone after ovulation are lower in the IS
regime
• This does not seem to influence the number of sows ovulating and
showing estrus
• Although IS6 sows seem to run a higher risk of developing cysts,
and have delayed LH surge, estrus, and ovulation
What about pregnancy?
Conception
C (n=16)
IS12 (n=9)
IS6 (n=7)
Pregnant
D23 (%)
94%
77%
78%
Ovulation
rate
25±1.1
26.4±0.9
24.8±2.6
62±6
58±6
57±7
Embryonic
survival (%)
a,b
different superscripts in one row P<0.05
Embryo development
Treatment
C (n=16)
IS12 (n=9)
IS6 (n=7)
Embryo weight (g)
0.20 ± 0.01a
0.18 ± 0.02a,b
0.14 ± 0.01b
Rump length (mm)
19.5 ± 0.4
20.2 ± 0.5
20.1 ± 0.5
Placental length
(cm)
20.4 ± 0.9a,cd
19.7 ± 1.1ab,c
15.9 ± 1.1b,d
Implantation area
(cm2)
121.5 ± 6.5a
107.4 ± 8.0a,b
92.1 ± 8.5b
a,b
different superscripts in one row P<0.05,
c,d
different superscripts in one row P<0.10
Preliminary conclusions
•
•
•
•
Lactational estrus/ovulation easily induced in IS12 model
Ovulation IS6 sows seems affected
Pregnancy rate (?) and early embryonic survival not affected in IS12
Placental characteristics, embryonic development seems affected by
IS6
But:
• LH surge? – stage of lactation
• Progesterone output? – LH surge, feed intake, growth factors
• All breeds?
• Conceptus development during later stages of gestation?
Feed intake afer ovulation and progesterone
40
35
Progesterone, ng/ml
30
25
20
15
High (n=8)
Low (n=9)
10
2004- CTR
5
2004- IS12
0
0
24
48
72
96
120
144
168
192
216
240
hours post ovulation
High/low feed intake from O to 6d after ovulation, subsequently weaning
High: fed to requirements
Low: High – 2.5 kg
Restoration of preovulatory LH centre in
Hypothalamus.
Bevers et al. 1981
LH surge and luteal function
New experiment
Stage of lactation influences LH surge and luteinisation?
3 treatments:
1. IS starts at D14
2. IS starts at D21
3. Control weaned at D21
IGF around weaning
weaning
IGF and luteal function
Fitted slope in progesterone rise, ng/ml.h
0.6
0.5
0.4
2004
0.3
2005
1997
0.2
0.1
0
0
50
100
150
200
250
300
IGF around 1d post-ovulation, ng/ml
2004: IS model
2005: IS model
1997: weaned, primiparous sows
350
400
New experiment
Stage of lactation influences LH surge and luteinisation?
3 treatments:
1. IS starts at D14
2. IS starts at D21
3. Control weaned at D21
Wean at ovulation or 30d after
IS in a different breed
IS12 model, using Dutch Landrace x Yorkshire
Boar contact 3x/d, from start of IS (D14)
BOAR
NO BOAR
N=16
N=16
Spontaneous ovulation
5
4
Cystic
1
1
Anovulatory
10
11
Treated with PG600*
9
9
*Of the 21 anovulatory sows, 3 sows were removed from the experiment before treatment with PG600
Sows with ovulation showed estrus, whereas anovulatory sows did not
Estradiol
ovulation
no ovulation
cystic
40
35
E2 (pg/ml)
30
25
20
15
10
5
0
0
2
4
6
8
10
Days from IS
12
14
16
18
Follicle development
10
OVU
9
diameter of the largest follicles
ANOVU
8
7
max
6
5
4
min
3
2
1
0
0
2
4
6
8
10
d after start of IS
12
14
16
Estradiol in relation to follicle growth
40
OVU
35
ANOVU small
ANOVU large
Oestradiol pg/ml
30
25
20
15
10
5
0
0
1
2
3
4
5
d after start of IS
6
7
8
9
Conclusion
IS model is promising, but room for improvement
Timing of start of IS – luteinisation
Timing of weaning – developing conceptus
Breed differences
Thank you !
290
Weight sows (kg)
280
270
260
250
C
240
IS12
230
IS6
220
210
d6
d13
d20
d27
Day of lactation
d34
d42
Nutrients and villous atrophy
UW unweaned
SMH sow milk high
WD weaned on dry feed
SML sow milk low
Day 4 ME intake
1470
589
557 kJ/BW0.75
The drop in nutrient supply is a major cause of intestinal atrophy
Van Beers-Schreurs, 1998
SISP – small intestine segment perfusion test
Kuller et al., 2002
Feed intake and absorptive function
eater (n=9)
1000
non-eater (n=7)
eater + Coli
fluid absorption (μl per cm2)
non-eater + Coli
800
600
400
200
0
1
2
3
4
5
-200
-400
small intestine segment
Piglets that eat already during lactation have better intestinal
absorptive function post weaning
Kuller et al., 2002
Intermittent suckling
From 2 weeks of
lactation, sows
and piglets are
separated for 12
h per day