Toggle Main Menu Toggle Search

Open Access padlockePrints

The structure of feeding behavior in commercial broiler lines selected for different growth rates

Lookup NU author(s): Professor Ilias Kyriazakis


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Selection for increased growth rate in livestock is accompanied by increased requirements for food resources. It has been suggested that more intensively selected birds, such as broilers, have altered food intake control mechanisms and may be constantly hungry, due to the high demands of fast growth rates. If this is the case, it would be a major welfare issue. We investigated the hypothesis that more intensive selection for growth in some lines of broilers has altered feeding behavior by analyzing short-term feeding behavior bouts in relation to the roles of hunger and satiety mechanisms in the control of food intake. Using 4 genetic lines, resulting from different levels of selection for growth rate, meal pattern analysis was performed and the bouting of short-term feeding behavior was estimated. All lines showed bouted feeding behavior, although differences in meal size, number of meals, and meal duration were evident across lines. In all lines, the probability of birds starting a new meal was low immediately after finishing the previous meal and increased with time, as expected for feeding behavior governed by hunger and satiety mechanisms. Normal feeding behavior was, therefore, not affected by the intensity of selection. Feeding rate increased with growth rate, suggesting that this may be a consequence of selection. However the other characteristics of feeding behavior, such as meal duration, did not change consistently with higher growth rate. Due to differences between lines in bird size, the number and weight of birds per pen also differed between the lines. The differences in feeding behavior between lines were greatly diminished when weight of birds per square meter was taken into account but were still statistically significant. Overall, it is apparent that even when growth rate and body size have been substantially altered by genetic selection, the underlying normal controls of feeding behavior are conserved in broiler birds.

Publication metadata

Author(s): Howie JA, Tolkamp BJ, Avendano S, Kyriazakis I

Publication type: Article

Publication status: Published

Journal: Poultry Science

Year: 2009

Volume: 88

Issue: 6

Pages: 1143-1150

ISSN (print): 0032-5791

ISSN (electronic): 1525-3171

Publisher: Poultry Science Association Inc.


DOI: 10.3382/ps.2008-00441


Altmetrics provided by Altmetric