Description of the causes of stress in breeding and laying hens and consequences on physiology and productivity. http://www.plusvet.eu/egg-production-drop-caused-by-stress/

1. Stress in
breeders and layers

2. Hens and chickens are fearful animals,
very sensitive to stress.
They are creatures of habit.

3. Cold or heat
Disease Vaccinations
Defective Changes in
ventilation
Causes environment
of
stress
Changes in
Overcrowding
feed
Excessive or
Noise irregular
handling

4. Consequences of stress:
1) Worse livability and poorer body condition
Specially influenced by environmental conditions
(temperature, caging system).
2) Changes in the morphology of internal organs.
Liver status, bone resistance
to breakage, etc.

5. Consequences of stress:
3) Endocrinal and blood changes.
Decreased Ca2+ transport Egg shell defects
in blood.
Water and sodium retention.
Hormonal changes.

6. Consequences of stress:
4) Changes in feed intake and use.
Reduction of feed intake.
Worse feed use
Metabolic changes in digestive system that favor the onset of
infections.

7. Consequences of stress:
5) Worse immunity.
Immune system is depressed,
showing fewer circulating lymphocytes
and less antibody response.

8. Consequences of stress:
6) Effects on reproduction and egg quality.
-Cessation or reduction of laying,
-Atrophic follicles.
- Decreased oviduct weight.
- Higher percentage of defective eggs
(cracked, weak or dirty).