Abstract
Incubation and hatching commonly takes places at hatcheries, separate from the grow-out facilities where broiler
chicks are raised. This means that chicks are sorted and transported immediately after hatch, during which time
they typically do not have access to feed and water, and are subjected to transport stress. Recently, innovative
housing systems are being developed in which fertilised eggs are transported on embryonic day 18 (E18) from
the hatchery to the grow-out facility, where they hatch on day 21. In chicken, the hypothalamic–
pituitary–adrenal (HPA)-axis becomes functional around embryonic day 14–16. It is therefore conceivable
that transport of eggs at E18 may lead to a stress response in the chick embryo. Exposure to prenatal stress may
affect the coping capacity of the individual and negatively impact its further development. We investigated
whether prolonged transport on E18 has effects on the development of a slow growing broiler chicken strain
(Hubbard JA257). E18 eggs were transported for either 41 min (short transport, ST) or 219 min (long transport,
LT). Transportation significantly increased embryonic heart rate after ST. This increase continued during an
intermediate measure at 120 min. The increased embryonic HR then remained high at measurement immediately
following LT. We did not find effects of prolonged transport on behavioural parameters measured in the juvenile
chicken in the tonic immobility and open field test. Concentrations of feather corticosterone as well as faecal
corticosterone metabolites did not differ on postnatal day 36. We showed that transport leads to an autonomic
stress response in chicken embryos at E18, but that this elevation had no further effects on other indicators of
prenatal stress. Nevertheless, our results emphasise that transport of incubated eggs should be as refined as
possible to minimise the exposure to stress.
chicks are raised. This means that chicks are sorted and transported immediately after hatch, during which time
they typically do not have access to feed and water, and are subjected to transport stress. Recently, innovative
housing systems are being developed in which fertilised eggs are transported on embryonic day 18 (E18) from
the hatchery to the grow-out facility, where they hatch on day 21. In chicken, the hypothalamic–
pituitary–adrenal (HPA)-axis becomes functional around embryonic day 14–16. It is therefore conceivable
that transport of eggs at E18 may lead to a stress response in the chick embryo. Exposure to prenatal stress may
affect the coping capacity of the individual and negatively impact its further development. We investigated
whether prolonged transport on E18 has effects on the development of a slow growing broiler chicken strain
(Hubbard JA257). E18 eggs were transported for either 41 min (short transport, ST) or 219 min (long transport,
LT). Transportation significantly increased embryonic heart rate after ST. This increase continued during an
intermediate measure at 120 min. The increased embryonic HR then remained high at measurement immediately
following LT. We did not find effects of prolonged transport on behavioural parameters measured in the juvenile
chicken in the tonic immobility and open field test. Concentrations of feather corticosterone as well as faecal
corticosterone metabolites did not differ on postnatal day 36. We showed that transport leads to an autonomic
stress response in chicken embryos at E18, but that this elevation had no further effects on other indicators of
prenatal stress. Nevertheless, our results emphasise that transport of incubated eggs should be as refined as
possible to minimise the exposure to stress.
Original language | English |
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Article number | 105789 |
Pages (from-to) | 1-10 |
Journal | Applied Animal Behaviour Science |
Volume | 257 |
Early online date | 9 Nov 2022 |
DOIs | |
Publication status | Published - Dec 2022 |
Bibliographical note
Funding Information:This research was funded by the Dr. J.L. Dobberke Foundation for Comparative Psychology (Grant number KNAWWF/DA/3211/08).
Funding Information:
The authors would like to acknowledge support from Marius Dwars for monitoring the health of the chickens; Mona Giersberg for aid with the health scoring; Marijke Achterberg for support with behaviour observations and Melissa de Jong for help with analysing the open field data; Susanne Kirchhoff and Judith Hendriks for support with the lab procedures; and Wim Brenk and Patricia Gadella for animal care.
Publisher Copyright:
© 2022
Keywords
- Glucocorticoid
- In ovo
- Non-invasive monitoring
- Poultry
- Stress
- Welfare