Effects of lighting regimen on metabolic rate in broilers
| Autor: | A.M. Henken, M.J.W. Heetkamp, C. W. Scheele, W. van der Hel |
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| Rok vydání: | 1992 |
| Předmět: | |
| Zdroj: | Netherlands Journal of Agricultural Science 40 (1992) Netherlands Journal of Agricultural Science, 40, 111-121 |
| ISSN: | 0028-2928 |
| DOI: | 10.18174/njas.v40i2.16518 |
| Popis: | From hatching to 42 days old, 80 broilers were exposed to varying periods of light (L) and dark (D) within 4-h periods (0.5L to 1.5L and 3.5D to 2.5D). Effects of lighting regimen (LR) and trough position (open (F2) compared with closed (F1)) during D-periods on heat production (H), activity-free (Hacf) and activity-related H (Hac), and respiratory quotient (RQ) were evaluated. At 0.5L and 0.67L, Hac was less than in the longer L-periods. The longer the L-period, the less active broilers were at the end of a L-period. In D-periods with F1, H and Hacf decreased more than with F2, while Hac was similar. After D-periods with F1, H and Hacf increased more than after D-periods with F2. This effect on H was greatest in short L-periods with F1. With 0.5L:3.5D and F1, broilers did not have enough feeding time, because at the end of the L-period afterwards, H and RQ were lower than with the longer L-periods. Thus, broilers will eat feed in the dark and the length of L-period may not be crucial, because in practice, feed will remain available in the dark. (Abstract retrieved from CAB Abstracts by CABI’s permission) |
| Databáze: | OpenAIRE |
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