Activities per year
Abstract
During incubation, an eggshell temperature (EST, as a reflection of embryo temperature)
of 37.8°C was long considered to be optimal for broiler embryonic development.
However, an EST of 36.7°C (Cold) from embryonic day (E)15 onward may result in a
more developed heart at hatching than 37.8°C EST throughout (Control; Maatjens et al.,
2016). Maatjens et al.’s study was performed in large incubation chambers with low air
velocity, unlike commercial practice. To study Cold EST in a commercial situation with
high air velocity and egg density, three trials were conducted. In all trials, EST for Cold
was maintained at 37.8°C, decreased to 36.7°C with varying profiles in the last week,
and then maintained at 36.7°C till hatching. Cold treatments were always compared to
Control (37.8°C EST throughout incubation). 3,000-10,800 broiler eggs from a 30-39
week old parent flock were used. Firstly, EST was decreased within 30 minutes, on E15.
Compared to Control, Cold resulted in 2.5x higher embryonic mortality around the time
of the EST decrease (P = 0.015), 2.2% more second grade chicks (P = 0.049), and chicks
were 0.4cm shorter (indicating lower development) at hatch (P = 0.001). Possibly, the
EST decrease happened too early or abruptly. Secondly, EST was decreased gradually in 1
day, from E16-E17. No differences were found in hatchability (P = 0.68) or chick length
(P = 0.93), but embryonic mortality around the time of the EST decrease tended to be
1.7x higher for Cold than for Control (P = 0.070). It was thought that an even slower EST
decrease may optimize Cold further. Thirdly, EST was decreased using three different
profiles. EST was decreased gradually from E16-E17, or quickly (to 36.9°C on E17) and
then slowly (to 36.7°C on E18), or slowly (to 37.5°C on E17) and then quickly (to 36.7°C
on E18). Embryonic mortality, hatchability, and navel quality did not differ between
the Cold profiles and Control (P > 0.29). To conclude, results differed from the low air
velocity trial situation. When EST was decreased from 37.8°C to 36.7°C abruptly or too
early in development, hatchability and chick quality decreased. A slow transition from
E16-E18 can result in chick quality and hatchability similar to Control. Knowledge on
these optimal EST decrease profiles can be used to further investigate the effect of Cold
incubation during the last days of incubation on post hatch performance and possibly
apply it to commercial practice.
Original language | English |
---|---|
Title of host publication | The XVth European Poultry Conference (EPC) |
Subtitle of host publication | Conference information and Proceedings |
Editors | Estella Prukner-Radovčić, Helga Medić |
Place of Publication | Zagreb, Croatia |
Pages | 126-126 |
Publication status | Published - 2018 |
Event | The XVth European Poultry Conference - Dubrovnik, Croatia Duration: 17 Sep 2018 → 21 Sep 2018 |
Conference
Conference | The XVth European Poultry Conference |
---|---|
Country | Croatia |
City | Dubrovnik |
Period | 17/09/18 → 21/09/18 |
Activities
- 1 Oral presentation
-
Applying cold incubation profiles during the last week of incubation in a commercial incubator: effects on broiler embryonic mortality, hatchability, and chick quality
Inge Van Roovert-Reijrink (Contributor), Marieke Priester (Contributor), H.J. Wijnen (Speaker) & C.W. van der Pol (Contributor)
20 Sep 2018Activity: Talk or presentation › Oral presentation › Other