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| Leenstra, Ferry; Maurer, Veronika; Bestman, Monique; Zeltner, Esther; van Niekerk, Thea; Galea, Fabien; Reuvekamp, Berry. |
| In poultry, breeding is carried out by a very limited number of international operating breeding companies. For laying hens two companies dominate the market. Laying hens are in general 4-way crosses. Since 1960 the majority of commercial layers are bred and housed in cages. Non-cage housing started to appear again from 1980 onwards and increases slowly in importance, at first in Europe, but recently also in North America. It is questionable if birds bred to perform in cages are also suited for free range housing. In this project we examine the performance of current genotypes in free range systems (organic and conventional), and if and how an improved genotype for free range housing can be developed. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Breeding and genetics; Poultry. |
| Ano: 2011 |
URL: http://orgprints.org/18709/1/Leenstra%2DPoultry%2Daims.pdf |
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| Bestman, Monique; Leenstra, Ferry; Maurer, Veronika; van Sambeek, Frans; Zeltner, Esther; Reuvekamp, Berry; Amsler, Zivile; Galea, Fabien; van Niekerk, Thea. |
| Free range and organic systems provide different circumstances for laying hens than closed houses or cages, where most hens are selected in. An enquiry and farm visits were done in The Netherlands, Switzerland and France in order to find out what genotypes are being used and how they perform. There are differences between countries, systems (organic vs free range) and groups of breeds. There is not just one genotype suitable for organic and free range systems. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Breeding and genetics; Health and welfare; Poultry. |
| Ano: 2012 |
URL: http://orgprints.org/21734/1/bestman-etal-2012-lbf_sh_362-p355-359.pdf |
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| Leenstra, Ferry; Maurer, Veronika; Bestman, Monique; van Sambeek, Frans; Zeltner, Esther; Reuvekamp, Berry; Galea, Fabien; van Niekerk, Thea. |
| 1. A total of 257 farmers with free ranging laying hens (organic and conventional) in Switzerland, France and The Netherlands with 273 flocks were interviewed to determine the relationships between the genotype of the hens, management conditions and performance. 2. Almost 20 different genotypes (brands) were present on the farms. In France, all birds were brown feathered hens laying brown eggs. In Switzerland and The Netherlands, there were brown, white (white feathered hens laying white eggs) and silver (white feathered hens laying brown eggs) hens. In Switzerland, mixed flocks were also present. 3. The overall effect of system (organic vs. conventional free range) on egg production and mortality was significant, with higher mortality and lower egg... |
| Tipo: Journal paper |
Palavras-chave: Breeding and genetics; Health and welfare; Poultry. |
| Ano: 2012 |
URL: http://orgprints.org/21650/1/LIBlayersBPS2012.pdf |
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| Mul, M.F.; van Niekerk, Thea; Chirico, J.; Maurer, Veronika; Kilpinen, O.; Sparagano, O.; Thind, B.; Zoons, J.; Moore, D.; Bell, B.; Gjevre, A.-G.; Chauve, C.. |
| This paper reports the results of a seminar on poultry red mite (PRM), Dermanyssus gallinae. Eighteen researchers from eight European countries discussed life cycle issues of the mite, effects of mites on hens and egg production, and monitoring and control methods for PRM in poultry facilities. It was determined that PRM probably causes more damage than envisaged, with the cost in The Netherlands alone reaching 11 million euro per annum. However a great deal is still unknown about PRM (e.g. reproduction, survival methods, etc.) and that PRM monitoring is an important instrument in recognising and admitting the problem and in taking timely measures. Currently, the most promising control method combines heating the hen house in combination with chemical... |
| Tipo: Journal paper |
Palavras-chave: Health and welfare. |
| Ano: 2009 |
URL: http://orgprints.org/19930/1/Mul_et_al_2009.pdf |
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| Leenstra, Ferry; Maurer, Veronika; Bestman, Monique; van Sambeek, Frans; Zeltner, Esther; van Niekerk, Thea; Galea, Fabien; Reuvekamp, Berry. |
| Since 1960 the majority of commercial layers are housed in cages. Non-cage housing started to appear again from 1980 onwards and increases in importance. It is questionable if birds bred to perform in cages are also suited for free range housing. We examined the performance of current genotypes in free range systems (organic and conventional) by an inventory among laying hen farmers in Switzerland, The Netherlands and France (325 flocks on 275 farms) and organised workshops with farmers to discuss their ideas on breeding goals (‘the ideal hen’) for free range systems. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Breeding and genetics; Health and welfare; Poultry. |
| Ano: 2011 |
URL: http://orgprints.org/20558/1/leenstra-etal-2011-LowInputBreeds-Edinburgh_layers.pdf |
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