Long-lasting effects of

thermal manipulations

during embryogenesis in

broiler chicken

T. Loyau, S. Métayer-Coustard, C. Berri, S. Mignon-Grasteau, C. Hennequet-Antier, M.J.

Duclos, S. Tesseraud, C. Praud, N. Everaert, M. Moroldo, J. Lecarbonnel, P. Martin, V. Coustham,

S. Lagarrigue, S. Yahav, A. Collin

Context

Poultry: efficient protein source

Huge global development

Chicken

Turkey

Duck

- Avian selection in

temperate conditions

- Industrial egg incubation

in controlled conditions

Efficient in controlled conditions but…

Sensitive to temperature

variations

Climate change

Cressensac. La Dépêche du Midi 2003, France C. Nyuiadzi, Togo

Broiler chicken

E0 E21=j0 Control Incubation 37.8°C, 56% RH

E0 E21=j0

Piestun et al., Poult. Sci., 2008

E7 E16 39.5°C, 65% RH 12h/d 37.8°C, 56% RH

Thermal manipulation during embryogenesis (TM)

- Lower body temperature from hatching to slaughter age

- 50% lower mortality in males submitted to 35°C during 5h at slaughter age

Physiological and metabolic mechanisms involved in

the acquisition of embryo acclimation?

Strategy to improve robustness?

E0 E21=j0 Control Incubation C 37.8°C, 56% RH

E0 E21=j0

Piestun et al., Poult. Sci., 2008

E7 E16 39.5°C, 65% RH 12h/d 37.8°C, 56% RH

Thermal manipulation during embryogenesis (TM)

Material and methods

21°C C

21°C TM

32°C/5h CCh

32°C/5h TMCh

Performance

Physiology Metabolism

Gene expression

Physiological and metabolic

mechanisms involved in the acquisition

of embryo acclimation?

D34

D34

Meat quality

Performance: No modification in hatchability, slightly lighter (-1,4%) but less fat

No alteration in meat processing quality by TM

Performance and physiological parameters

C TM

Hatching rate (% fertile eggs) 86,13 83,19 NS

Body weight 28d 1525 ± 14 1534 ± 14 NS

Feed conversion ratio d0-d28 (g/g) 1.49 ± 0.02 1.47 ± 0.02 NS

Body weight 35d (g) 2185 ± 19 2156 ± 19 P < 0.05

Loyau et al., 2013

Animal scale

Body temperature (Tb):

21°C 37.5

38.5

39.5

40.5

41.5

42.5

d0 d28

***

***

21°C 32°C

Stress: Heterophil/Lymphocyte ratio:

0

0.1

0.2

0.3

0.4

0.5

0.6 a

b b

b

C CCh TM TMCh

°C

Performance and physiological parameters

d28

2

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

C TM

T3 (nmol/L) a

b

TM (150) C (170)

d34

Loyau et al., J. Anim. Sci., 2013

Physiology scale

Respiratory physiology

Physiology scale

0

10

20

30

40

50

60

70

80

90

100

C MT CCh MTCh

O2 sat

0

10

20

30

40

50

60

70

C MT CCh MTCh

pCO2

P (incubation) < 0,05

TM TM O2 Sat

C TM TMCh CCh C TM TMCh CCh

P (incubation) < 0,05 P (challenge) < 0,05

d34 pCO2

Modification of respiratory physiology by

TM during embryogenesis?

Candidate markers of thermotolerance? Gene scale

a

b ab ab

0

0.5

1

1.5

2

2.5

3

C TM CCh TMCh

PGC-1α (Mitochondrial biogenesis) J34

Example:

Long-lasting effects of TM during embryogenesis on genes expression

Regulation of metabolic heat production?

Gene expression analysis on microarray in breast muscle at d34

Control vs TM n=28

Control vs

Control+Challenge

TM vs C n=28 TMCh vs TM

n = 759

CCh vs C

n = 128

- Metabolic regulations

- Chromatine modifications

- Vascularization

- Stress response

= earlier or more responsive!

New markers of thermotolerance?

Limitation of mitochondrial energy metabolism and heat

production

Gene scale

Modification of respiratory

physiology

Stress

↓ Stress in hot

conditions (H/L)

Thyroid hormones

Modification plasmatic thyroid

hormone concentration (J28)

↓ Oxidative stress

Energy metabolism

regulation

↓ internal temperature

+/- long term

Régulation metabolic heat? Modification of vascularisation ?

Acclimation to heat

Take home message Physiological and metabolic mechanisms involved in the acquisition of

embryo acclimation?

Thank you for your attention and thanks to

Projet « Jeunes Chercheuses et Jeunes Chercheurs » ANR-09-JCJC-0015-01 THERMOCHICK

A. Collin

S. Crochet

E. Cailleau-Audouin

S. Métayer-Coustard

C. Berri

S. Tesseraud

V. Coustham

M. Leduc

L. Bouyer

M. Sannier

T. Bordeau

E. Godet

E. Baéza

C. Praud

N. Rideau

N. Courroussé

L. Dillet

L. Bedrani

P. Chartrin

J. David

E. Coudert

M. Duclos

S. Mignon-Grasteau

C. Hennequet-Antier

E. Le Bihan-Duval

M. Couty

M. Chabault

P. Martin and team

J. Delaveau

F. Mercerand

H. Rigoreau

N. Sellier

C. Le Bourhis

J.M. Brigant

F. Favreau

O. Callut

C. Rat

D. Mailler

Inra experimental units

C. Theuleau

F. Breton

B. Guillerm

P. Didier

D. Gourichon

JM Meslier

B. Nowakowski

B. Gauthier

N. Besné

Other labs

S. Yahav, Israël

S. Yalçin, Turquie

N. Everaert, Belgique

S. Lagarrigue

F. Pitel and team

M. Bergès

T. Zerjal

Inra research team