?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Genetic+Improvement+of+Livestock+for+Organic+Farming+Systems&rft.creator=Boelling%2C+Dr.+Dorothe&rft.creator=Groen%2C+Dr.+Ab+F.&rft.creator=S%C3%83%C2%B8rensen%2C+Prof.+Poul&rft.creator=Madsen%2C+Dr.+Per&rft.creator=Jensen%2C+Dr.+Just&rft.subject=+Breeding+and+genetics&rft.description=Over+the+last+two+decades%2C+more+and+more+farmers+converted+from++conventional+to+organic+farming+systems.+The+few+breeds+and+genetic+lines+which+are+intensively+used+in+conventional+production+systems+are+not+necessarily+well+adapted+to+the+conditions+in+organic+farming%2C+because++genotype+*+environment+interactions+may+cause+individual+genotypes+performing+well+in+one+environment+to+do+poorly+in+another+surrounding.+%0D%0AAn+example+in+poultry+is+given%2C+illustrating+that+laying+hens+which+were+selected+for+high+egg+production+in+a+cage%2C+had+a+considerable+decrease+in+number+of+eggs+laid+in+a+free-range+system+and+furthermore+developed+unfavourable+behaviour+patterns+like+feather+pecking.+The+range+of+phenotypes+produced+by+one+genotype+can+be+determined+by+variation+in+the+environment+and+visually+demonstrated+in+reaction+norm+curves.+As+one+example+for+this+phenomenon%2C+reaction+norm+curves+depicting+the+environmental+sensitivity+for+fertility+in+dairy+cattle+were+shown.+%0D%0AIt+is+suggested+to+develop+new+selection+indices+and+to+apply+them+to+the+existing+stock.+Different+possibilities+for+these+new+indices+which+contain+production+as+well+as+functional+or+fitness+traits+are+given.+Summing+up%2C+organic+farming+systems+may+crave+a+different+type+of+livestock+which+can+be+accounted+for+in+a+breeding+context.%0D%0A&rft.date=2003&rft.type=Journal+paper&rft.type=NonPeerReviewed&rft.format=text%2Fhtml&rft.identifier=http%3A%2F%2Forgprints.org%2F1566%2F1%2FScienceDirect_-_Livestock_Production_Science__Genetic_improvement_of_livestock_for_organic_farming_systems.htm&rft.identifier=Boelling%2C+Dr.+Dorothe%3B+Groen%2C+Dr.+Ab+F.%3B+S%C3%83%C2%B8rensen%2C+Prof.+Poul%3B+Madsen%2C+Dr.+Per+and+Jensen%2C+Dr.+Just+(2003)+Genetic+Improvement+of+Livestock+for+Organic+Farming+Systems.+Livestock+Production+Science%2C+80%2C+pp.+79-88.+**&rft.relation=http%3A%2F%2Forgprints.org%2F1566%2F