Case Studies using Molecular Data in Breed Conservation
| Autor: | Bernt Guldbrandtsen, Vivi Hunnicke Nielsen, Anna Schönherz |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Zdroj: | Guldbrandtsen, B, Nielsen, V H & Schönherz, A 2018, ' Case Studies using Molecular Data in Breed Conservation ', Workshop on Genomic Selection. Espoo 2018, Helsinki, Finland, 30/11/2018-30/11/2018 . Aarhus University |
| Popis: | In this presentation, I will present a couple of case studies where we have exploited DNA marker information in the management of Danish conservation breeds.Expansion of the Breeding Population in Danish Pig BreedsThere are two Danish conservation breeds of pigs, Danish Landrace Pigs (DLP) and Danish Pied Pigs (DPP). Despite a recent moderate commercial success for the DPP, both breeds are highly endangered. Population sizes for both breeds are critically small. A number of animals are supposed however to have pure origin in these breeds, but their pedigree information is incomplete, unreliable, or even missing. Using SNP array data it is possible to detect population structure and admixture. Combining data from a global reference data set, from study of the Danish pig breeds with data collected ad hoc, we were able to show that several animals were suitable as candidates to expand the breeding pool of animals. The same comparison revealed recent unwanted admixture of some DPP animals with genetics from Gloucester Old Spot, a British breeds supposed to be part of the genetic origin of DPP.Breed Definition in Danish SheepTwo sheep breeds are recognized as tradition in Denmark. These are the White-Headed Marsh Sheep and Danish Landrace Sheep (DLS). The current stock of DLS go back to three herds: Hulsig, Vesterbølle, and Ertebølle. Ertebølle sheep descend from a very small stock of animals rescued from slaughter by a dedicated breeder. These were used to found a five-component rotational mating scheme at one farm. Several other breeders have obtained sheep from this farm. Principal component analysis of SNP array data clearly reveals the structure of the population. Sheep of Hulsig and Vesterbølle origin were to some extent admixed with each other. Sheep from the Ertebølle line were the genetically most distinct group. Animals with either 25 or 50% Ertebølle origin could be identified. The genetic composition within the Ertebølle group was quite homogeneous. This is consistent with the use of a rotational breeding scheme with will tend to remove within group differences.Admixture in Danish Landrace ChickenA population of Danish Landrace Chicken (DLC) still exists. It is maintained by a small group of dedicated breeders. In addition to a traditional type of this breed, a number of color and morphological variants exist. An admixture analysis of the chicken reveals a number of distinct origins in the population. Flocks of different breeders represent the different origins to different degrees. The color and morphological variants appear to be associated with one of the origins. At this point, it remains unclear whether this represents unwanted admixture associated with import of the variants originating in other breeds. Chip typing of animals from potential donor breeds is in progress. The objective is to determine whether this genetic origin represents a distinct DLC origin, or whether it represents admixture with other breeds.ConclusionUsing molecular data breeding and management decisions in conservation breeds can be supported scientific information. Problems, which would otherwise possibly be undetectable and certainly could not be solved, can be solved in a satisfactory manner using molecular information. |
| Databáze: | OpenAIRE |
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