Heat Stress Alleviation in Lactating Sows by Dietary Betaine Supplementation and Cooling Pads - Francisco Cabezon, from the 2017 Allen D. Leman Swine Conference, September 16-19, 2017, St. Paul, Minnesota, USA. More presentations at http://www.swinecast.com/2017-leman-swine-conference-material

1. HEAT STRESS ALLEVIATION IN LACTATING SOWS
BY DIETARY BETAINE
SUPPLEMENTATION AND COOLING PADS
Francisco A. Cabezón
September, 2017

2. INTRODUCTION
Sows are susceptible to high ambient temperatures and humidity.
Modern sows produce more heat due to greater milk production and feed intake.
(Stinn and Xin, 2014; Brown-Brandl et al., 2014; Cabezón et al., 2017).
More than 60% of randomly sampled sow farm operations in the U.S., reported a
decline in fertility during the hot summer months (Knox et al., 2013).

3. CONSEQUENCES OF HEAT STRESS
IN SOWS AND BOARS
Body Core TemperatureFeed Intake
Negative Energy Balance
Skin Blood Flow
GIT Blood Flow
Ovarian Blood Flow
Respiration Rate
GnRH and LH
Estradiol Secretion
Estrus Expression
Follicular Growth
Total Sperm
Abnormal Sperm
Fertilization Rate

4. WHY BETAINE?
• Tri-methyl-glycine.
• Zwitterion molecule.
• Organic osmolyte.
• Reduces homocysteine levels.
• Enhances methionine availability.
Elklund et al. (2005)

5. BETAINE: EXPERIMENT 1
Hypothesis
Supplementation of betaine during summer can alleviate heat stress and
improve lactation and reproductive performance in sows.
Objective
To evaluate the effects of betaine supplementation during summer on sow’s
lactation and reproductive performance.

6. MATERIALS AND METHODS
• Location: commercial sow facility, Rancagua, Chile.
• Time: December 15th, 2014 to July 31st, 2015 (summer lactation).
• Sample size: 368 sows.
• Treatments: control and 0.3% betaine-HCl (70.7% betaine, Beta-Key,
Excentials, Wenkerdam, Netherlands).
• Genetic lines: C-22 and L-42.
• Parity: P1, P2, P3-5 and P6+.
• Design: treatments randomly allotted to concurrent farrowing rooms.

7. BARN ENVIRONMENTAL CONDITIONS
Environmental variable Mean SD
Control
Temperature, ºF 78.9 2.3
Relative humidity, % 47.1 6.5
Dew point, ºF 56.4 3.0
Betaine
Temperature, ºF 78.6 2.4
Relative humidity, % 46.9 6.1
Dew point, ºF 56.1 3.0
Room environmental conditions.

8. STATISTICALANALYSIS
• MIXED Procedure in SAS version 9.2 (SAS. Inst. Inc. Cary NC).
- Dietary treatments (fixed effect).
- Genetic line (fixed effect).
- Parity (fixed effect).
- Rooms (random block)  4 consecutive farrowing rooms.
- Piglets allowed to nursed per sow (covariate)  current farrowing performance.
• Repeated measurements
- Feed intake.
• Chi-Square  WEI

9. Treatment P-value
Control Betaine SE Treatment Genetic Parity
Lactation variables, n 193 175
Initial weight, lbs 550.3 551.4 3.6 0.826 0.006 0.001
Weight at weaning, lbs 488.3 489.9 4.8 0.813 0.001 0.001
BW change, lbs -62.1 -64.2 2.6 0.571 0.732 0.001
Breeding variables, n 163 146
Weight at breeding, lbs 468.0 465.0 4.3 0.527 0.001 0.001
WEI, d 4.53 4.22 0.10 0.004 0.956 0.507
BODY WEIGHT AND WEAN TO ESTRUS INTERVAL
Means for sow body weight before farrowing, at weaning and at breeding
and wean to estrus interval for sows fed a control or betaine supplemented diet.
Initial weight = recorded before farrowing (112 d of gestation).
BW change = (weight at weaning – initial weight). WEI = wean to estrus interval. Sows with
10 < WEI < 3 d were excluded from the analysis.

10. Frequency Percent
WEI Control Betaine Control Betaine Chi-Square Prob
n 145 137 10.77 0.029
3 6 10 4.14 7.30
4 82 94 56.55 68.61
5 38 26 26.21 18.98
6 11 2 7.58 1.46
7-9 8 5 5.52 3.65
WEAN TO ESTRUS DISTRIBUTION
Mean wean to estrus intervals for sows fed a control or betaine supplemented diet.
WEI: wean to estrus interval.

11. Treatment P-value
Period Control Betaine SE Trt
1-5 days 11.7 11.7 0.2 0.994
6-11 days 13.8 14.5 0.2 0.001
12-16 days 15.3 16.0 0.2 0.003
17-21 days 16.0 16.6 0.2 0.019
Treatment Genetic Parity P-value
Control Betaine SE C-22 L-42 SE 1 2 3-5 6+ SE Trt Gen Par
N 193 175 191 177 86 120 164 43
ADFI, lbs 14.1 14.7 0.1 14.5 14.4 0.1 12.7 14.4 15.2 15.4 0.3 0.005 0.519 0.001
AVERAGE DAILY FEED INTAKES
Least-squares means for overall mean daily feed intake (lbs/d).
Least-square means for mean daily feed intake (lbs/d) by period of lactation.
Treatment by period
interaction (P <0.001).

12. CONCLUSIONS
• Betaine supplemented sows had a greater daily feed
intake than control sows.
• Wean to estrus interval was reduced by 0.31 days in
betaine supplemented sows.
• Betaine supplementation shifted the distribution of
wean to estrus interval.
• No differences were found for lactation performance
and subsequent farrowing performance.

13. COOLING PADS: EXPERIMENT 2

14. HEAT PRODUCTION
Heat increment
+
Maintenance
requirements
300
350
400
450
500
550
600
650
1 3 5 7 9 11 13 15 17 19 21
Heatproduction,watts
Time, days
P1
P2
P3-5
P6+
Cabezón et al., 2017. Prof. Anim. Sci. (uses NRC, 2012)

15. HEATER
COOLING
PAD
WATER PUMP
ARTIFICIAL
SOW

16. PROTOTYPES
PROTOTYPE 2.0 (8 PIPES)PROTOTYPE 1.0 (6 PIPES)
Prototype Initial Plate
Temp (ºF)
Supply water
Temp (ºF)
Δ Temperature
(outlet-inlet ºF)
Water
usage
(gal)
Average Plate
Rejection (watts)
6 pipes 100.5 68.2 4.8 6.87 167.10
8 pipes 100.0 67.9 7.3 7.24 250.77
50.1%Cabezón et al., (2016) unpublished data

17. NEW PROTOTYPE
48.43 x 24.02 inches

18. OBJECTIVES
• To evaluate the impact of different water flow rates through the
cooling pad on the estimated amount of heat removal and reduction in
the sow’s responses to heat stress.

19. MATERIALS AND METHODS
• 10 multiparous sows (commercial crossbred Yorkshire and Landrace).
• Late lactation (15.3 ± 2.8 d).
• Treatments assigned to sows were switched randomly.
• 8 replicates.
CONTROL
0.00 L/m
0.00 gal/m
n = 4
LOW
0.25 L/m
0.066 gal/m
n = 2
MEDIUM
0.55 L/m
0.145 gal/m
n = 2
HIGH
0.85 L/m
0.225 gal/m
n = 2

20. HEAT REMOVAL =
• FLOW RATE (L/s)
• WATER DENSITY (kg/L)
• SPECIFIC HEAT OF WATER (J/kg ºC)
• ΔTEMPERATURE (ºC): Outlet - Inlet
L x kg x J x ºC
s x L x kg ºC
HEAT REMOVAL CALCULATION
WATTS

21. PROTOCOL OUTLINE
X time
Heater on
5 measurements
20 min 20 min 20 min
Cooling on
Cooling off
Heater off
Target
Temperature reached
RR: respiration rate, VT: vaginal temperature, ST: skin temperature, RT: rectal temperature,
INL: inlet temperature, OUT: outlet temperature, FLOW: water flow rate.
20 min
1 h
40 min 20 min
RR
ST
RT
IN
OUT
FLOW
IN
OUT
FLOW
IN
OUT
FLOW
IN
OUT
FLOWCalibration
RR
ST
RT
20 min
IN
OUT
FLOW
RR
ST
RR
ST
RR
ST
RR
ST
RR
ST
RT

22. STATISTICAL METHODS
• MIXED procedure in SAS.
- Repeated measurements with sow as repeated random effect.
- Treatment, cooling time and their interactions as fixed effects.
- Repetitions considered as random blocks.
• Multiple comparisons of means: Tukey Kramer method.
• All data are reported as least-squares means.
• Differences considered significant if P < 0.05 and a tendency if P < 0.10.

23. ENVIRONMENTAL VARIABLES
Temperature (ºF) Relative humidity (%) Dew Point (ºF)
Mean SD Mean SD Mean SD
Before trial 84.2 4.5 75.9 7.8 75.6 3.4
Prior to
cooling
95.2 0.7 68.5 3.1 82.9 1.8
0-20 min 95.0 0.5 69.3 3.3 83.3 1.6
20-40 min 95.2 0.5 69.4 3.6 83.5 1.8
40-60 min 95.5 0.4 68.0 3.0 83.1 1.6
60-80 min 95.4 0.7 67.5 3.5 82.9 1.8
80-100 min 95.2 1.3 67.8 3.0 82.8 1.8
Room environmental conditions.

24. RESPIRATION RATES
a
a
a
a
ab
ab
b
b
ab
bc
bc
bc
b
c
c
c
35
60
85
110
135
Before trial Prior to
cooling
0-20 min 20-40 min 40-60 min 60-80 min 80-100 min
Respirationrates,breaths/min
Protocol Phase
CONTROL
LOW
MEDIUM
HIGH
Treatment x time interaction (P < 0.001)
122
76
67
45
Least-square means for respiration rates during the trial.

25. a
a
a
a
ab ab
b
b
ab b b b
b b
b b
102.0
102.5
103.0
103.5
104.0
104.5
Before trial Prior to
cooling
0-20 min 20-40 min 40-60 min 60-80 min 80-100 min
Vaginaltemperature,ºF
Protocol Phase
CONTROL
LOW
MEDIUM
HIGH
VAGINAL TEMPERATURES
Treatment x time interaction (P = 0.004)
104.0
103.1
102.9
102.6
Least-square means for vaginal temperatures during the trial.

26. a
b
bc
c
101.5
102.0
102.5
103.0
103.5
104.0
104.5
Before trial Prior to cooling 80-100 min
Rectaltemperature,ºF
Protocol Phase
CONTROL
LOW
MEDIUM
HIGH
RECTAL TEMPERATURES
Treatment x phase interaction (P < 0.001)
104.0
103.1
102.6
102.2
Least-square means for rectal temperatures during the trial.

27. SKIN TEMPERATURES
Treatment x time interaction (P = 0.32)
Least-square means for skin temperatures during the trial.
a a
ab ab
ab ab
b b
99.0
101.0
103.0
105.0
Before trial Prior to
cooling
0-20 min 20-40 min 40-60 min 60-80 min 80-100 min
Skintemperature,ºF
Protocol Phase
CONTROL
LOW
MEDIUM
HIGH
102.9
102.2
102.0
101.5

28. HEAT REMOVAL
c
b b
b
a a
a
a
a
100
150
200
250
300
350
400
450
500
550
600
0-20 min 20-40 min 40-60 min 60-80 min 80-100 min
Heatremoval,watts
Protocol Phase
LOW
MEDIUM
HIGH
Treatment x time interaction (P < 0.001)
EFFECTIVENESS
LOW = 42.1 kJ/L
MEDIUM = 35.3 kJ/L
HIGH = 27.0 kJ/L
Least-square means for heat removal during the trial.

29. Inlet: 74.3ºF
Outlet: 88.0ºF

31. CONCLUSIONS
• The newly designed cooling pad was able to
reduce the signs of heat stress in sows.
• A water flow rate between 0.55 to 0.60 L/m
(0.145 to 0.158 gal/m) might be adequate to keep
the sows cooled in the long term.
• The LOW water flow rate limited the amount of
heat that could be removed by the cooling pad.

32. ACKNOWLEDGEMENTS
Thank you for your attention