Abstract
Heat represents a major stress factor in laying hens, but it is difficult to compare
published studies, done under very different conditions. A meta-analysis enabled us to make a
quantitative review of the results from 100 published papers. Relative effects of four factors (genotype,
age, group size and amplitude of temperature variation) were analyzed on feed intake, egg production,
egg weight, egg mass and FCR. The GLMselect procedure in SAS was used to select the best model
for each trait and to estimate the main effects and their interactions. Daily feed intake, egg mass and
hen-day egg production were more sensitive to heat stress as they varied from -16.2% to -19.8%
between 20 and 35°C while egg weight and FCR showed less variation (-3.8 to -6.4% between 20 and
35°C). Interactions were most often significant, which reinforces the interest of meta-analysis to
summarize literature data. This study highlighted that the impacts of heat stress in laying hens depends
on the genotype, age and the amplitude of temperature
| Original language | English |
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| Title of host publication | Proceedings of the 8th European Poultry Genetics Symposium, Venice, Italy, 25 - 29 September, 2013 |
| Place of Publication | Venice, Italy |
| Publisher | WPSA |
| Pages | 58 |
| Publication status | Published - 2013 |
| Event | 8th European Poultry Genetics Symposium, Venice, Italy - Duration: 25 Sept 2013 → 27 Sept 2013 |
Conference
| Conference | 8th European Poultry Genetics Symposium, Venice, Italy |
|---|---|
| Period | 25/09/13 → 27/09/13 |