title: Altered incubation temperatures between embryonic Days 7 and 13 influence the weights and the mitochondrial respiratory and enzyme activities in breast and leg muscles of broiler embryos.
abstract: Altering incubation temperature during embryogenesis has an impact on chicken embryo growth, but the underlying molecular mechanisms are not understood; the present study was performed to address these changes. Broiler eggs were incubated at low (36.8°C), control (37.8°C), and high (38.8°C) temperatures between Embryonic Day (ED) 7 and 10 or ED 10 and 13, which cover critical periods of embryonic myogenesis. The embryos were then dissected immediately after treatment on ED 10 or 13 to assess body, liver, and heart weights as well as to analyze breast and leg muscle fibers for their mitochondrial respiratory activity (MRA). Breast muscle samples were additionally used to evaluate the activity of enzymes involved in energy metabolism and cell-cycle progression. ED-10 embryos incubated at 38.8°C showed elevated weights (body, liver, and heart), MRA, and activities of lactate dehydrogenase and cytochrome oxidase compared to the ED-10 embryos incubated at 36.8°C. Similarly, the ED-13 embryos incubated at 38.8°C showed elevated body weight, MRA, and activities of glycogen phosphorylase, phosphofructokinase, and cytochrome oxidase compared to their 36.8°C counterparts. Embryos incubated at the normal temperature (37.8°C), however, showed variable differences from those incubated at 38.8°C versus 36.8°C. Cell-cycle enzyme activities were not impacted by the different temperature treatments. Thus, an increase or decrease in the incubation temperature during embryonic broiler myogenesis results in altered embryo activity, muscle energy metabolism, and activity-dependent muscle growth.
authors.affiliation: Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Foundation, Bischofsholer Damm, Hannover, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Krischek
authors.affiliation: Department of Animal Sciences, Quality of Food of Animal Origin, Georg-August-University Goettingen, Albrecht-Thaer Weg, Goettingen, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Janisch
authors.affiliation: Leibniz Institute for Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee, Dummerstorf, Germany.
authors.forename: Watcharapong
authors.initials: W
authors.lastname: Naraballobh
authors.affiliation: Leibniz Institute for Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee, Dummerstorf, Germany.
authors.forename: Ronald
authors.initials: R
authors.lastname: Brunner
authors.affiliation: Leibniz Institute for Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee, Dummerstorf, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Wimmers
authors.affiliation: Department of Animal Sciences, Quality of Food of Animal Origin, Georg-August-University Goettingen, Albrecht-Thaer Weg, Goettingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Wicke
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology*; D019069:Cell Respiration / Q000502:physiology*; D002642:Chick Embryo; D047108:Embryonic Development / Q000502:physiology*; D004734:Energy Metabolism; D004789:Enzyme Activation; D035002:Lower Extremity / Q000254:growth & development; D008931:Mitochondria, Muscle / Q000502:physiology*; D024510:Muscle Development / Q000502:physiology; D018482:Muscle, Skeletal / Q000201:enzymology / Q000254:growth & development; D013696:Temperature; D013909:Thorax / Q000201:enzymology / Q000254:growth & development