title: High- and low-temperature manipulation during late incubation: effects on embryonic development, the hatching process, and metabolism in broilers.
abstract: Temperatures continuously higher and lower than the standard incubation temperature by 3°C from embryonic d 16 until embryonic d 18.5 result in differential effects on embryonic development, the hatching process, and embryonic metabolism. Embryos in the high-temperature group were forced into a state of malnutrition by the temperature treatment, as reflected by reduced embryo growth and yolk consumption, resulting in a significantly lower chick weight at hatch. In addition, altered air cell and blood gases as well as a retarded hatching process further indicated reduced growth of embryos exposed to higher incubation temperatures during the latter part of incubation. In addition, hatchability was significantly reduced by the high-temperature treatment due to higher embryonic mortality during the treatment period and the hatching process. Levels of blood glucose, lactate, liver glycogen, plasma triglycerides, and nonesterified fatty acids indicated an altered carbohydrate and lipid metabolism for the high-temperature group. Although the hatching process of embryos exposed to lower incubation temperatures was also significantly retarded, their embryonic development and growth were strikingly similar to those of the control group.
authors.affiliation: Departement of Biosystems, K. U. Leuven, Kasteelpark Arenberg 30, 3001 Leuven, Belgium. hilke.willemsen@biw.kuleuven.be
authors.forename: H
authors.initials: H
authors.lastname: Willemsen
authors.forename: B
authors.initials: B
authors.lastname: Kamers
authors.forename: F
authors.initials: F
authors.lastname: Dahlke
authors.forename: H
authors.initials: H
authors.lastname: Han
authors.forename: Z
authors.initials: Z
authors.lastname: Song
authors.forename: Z
authors.initials: Z
authors.lastname: Ansari Pirsaraei
authors.forename: K
authors.initials: K
authors.lastname: Tona
authors.forename: E
authors.initials: E
authors.lastname: Decuypere
authors.forename: N
authors.initials: N
authors.lastname: Everaert
mesh_terms: D000818:Animals; D001831:Body Temperature; D002245:Carbon Dioxide / Q000032:analysis; D002642:Chick Embryo / Q000502:physiology*; D003080:Cold Temperature; D004528:Egg Shell / Q000502:physiology; D004531:Eggs; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005313:Fetal Death / Q000662:veterinary; D006358:Hot Temperature; D010100:Oxygen / Q000032:analysis; D013696:Temperature; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D015431:Weight Loss
chemical_list: D014284:Triiodothyronine; D002245:Carbon Dioxide; D013974:Thyroxine; D010100:Oxygen