151. Cold-induced enhancement of avian uncoupling protein expression, heat production, and triiodothyronine concentrations in broiler chicks.
- Author
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Collin A, Buyse J, van As P, Darras VM, Malheiros RD, Moraes VM, Reyns GE, Taouis M, and Decuypere E
- Subjects
- Animals, Body Weight, Eating, Gene Expression, Glyceraldehyde-3-Phosphate Dehydrogenases genetics, Iodide Peroxidase metabolism, Kidney enzymology, Liver chemistry, Liver enzymology, Male, Mitochondrial Uncoupling Proteins, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, Thyroxine analysis, Thyroxine blood, Triiodothyronine analysis, Avian Proteins genetics, Chickens metabolism, Cold Temperature, Mitochondrial Proteins genetics, Thermogenesis, Triiodothyronine blood
- Abstract
The relationships among avian uncoupling protein (avUCP) mRNA expression, heat production, and thyroid hormone metabolism were investigated in 7-14-day-old broiler chicks (Gallus gallus) exposed to a low temperature (cold-exposed chicks, CE) or a thermoneutral temperature (TN). After 7 days of exposure, CE chicks exhibited higher heat production (+83%, P<0.01), avUCP mRNA expression (+20%, P<0.01), and circulating triiodothyronine (T(3)) levels (+104%, P=0.07) for non-statistically different body weights and feed intake between 3 and 7 days of exposure as compared to TN chicks. Plasma thyroxine (T(4)) concentration was clearly decreased in CE chicks (-33%, P=0.06). The lower hepatic inner-ring deiodination activity (-47%) and the higher renal outer-ring deiodination activity (+75%) measured in CE compared to TN chicks could partly account for their higher plasma T(3) concentrations. This study describes for the first time the induction of avUCP mRNA expression by low temperature in chickens, as it has been previously shown in ducklings, and supports the possible involvement of avUCP in avian thermogenesis.
- Published
- 2003
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