Slow and steady wins the race? No signs of reduced welfare in smaller broiler breeder hens at four weeks of age
| Autor: | E. Hult, Johan Jönsson, A Calais, Caroline Lindholm, E. Berndtson, Jordi Altimiras, N. Yngwe |
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| Rok vydání: | 2015 |
| Předmět: |
Veterinary medicine
Coping (psychology) General Veterinary chicken growth media_common.quotation_subject broiler breeders Broiler Zoologi feed restriction General Biochemistry Genetics and Molecular Biology Open field animal welfare Tonic (physiology) stress Adult life Animal science Animal Science and Zoology Habituation Psychology Zoology Welfare Physiological stress media_common |
| Zdroj: | Animal Welfare. 24:447-454 |
| ISSN: | 2054-1538 0962-7286 |
| DOI: | 10.7120/09627286.24.4.447 |
| Popis: | Broiler breeder chickens are commonly reared under strict feed-restriction regimes to reduce obesity-induced health and fertilityproblems during adult life, and are assumed to experience a reduced welfare due to the resulting hunger. In these conditions, feedcompetition could influence the growth rate, so that the individuals falling behind in growth would experience more stress and hunger.We hypothesised that these chickens are poor competitors due to a reactive coping style and experience a further reduced welfaresituation before size-sorting (‘grading’) at four weeks of age. Our results from open field, tonic immobility and home pen activity monitoringshow signs of lower fear and higher home-pen activity levels in smaller hens and do not support the idea of reactive coping.H/L ratios of smaller hens were also found to be lower, indicating less stress in these birds. Dissections of smaller and larger fourweekbreeder hens may offer an explanation in the form of a relatively larger gastrointestinal tract in smaller birds. We argue thatthis is a form of habituation to restricted feeding, offering these birds a physiological stress coping mechanism, and that low earlygrowth rate may not always be a sign of poorer welfare in broiler breeders. Funding agencies: Swedish research council Formas [2013-293] |
| Databáze: | OpenAIRE |
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