Conservation & local programs

Conservation strategies for local Dutch sheep breeds: combining (genomic) diversity indicators

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Abstract

Breed diversity can be quantified in multiple ways, and breeds and their (genetic) relationships are subject to change. Various approaches exist to identify unique genomic and phenotypic features, and weight within- and between-breed diversity for conservation prioritization. This study evaluates multiple approaches and their combinations to inform and optimize conservation strategies for 15 local (sub)populations of Dutch native sheep breeds. Annual population demographics, genotypes and several phenotypic traits such as wool quality indicators, withers height, colour and tail length were available. After quality control of the genomic dataset 32,203 SNPs remained for 630 purebred animals of 15 (sub)populations (number of animals per breed: 26 - 52). Genomic analysis such as principal component analyses (PCA) and fixation index calculations (Fst) were used to identify genomic relatedness between (clusters) of breeds. For each phenotypic trait breed averages were compared to identify differences between breeds. Information on breeding goals, historical background and cultural context was used to integrate relevant socio-cultural dimensions. PCA and Fst's showed high genomic relatedness between some of the breeds forming different clusters. Within clusters large overlap exists genetically and to a lesser extent phenotypically, but not necessarily between the same breeds. Clusters were mainly explained by shared (recent) ancestry, geographics, breeding goal and level of exchange of breeding animals. Including socio-cultural factors were shown to have profound effects on the optimal conservation strategies. In one case, a recent split within an already endangered breed, caused by personal conflicts, resulted in two separated, even more vulnerable populations. Given the recent disputes collaboration between the breeds is not feasible and losing either breed would lead to a loss of genetic diversity. Consequently, the socio-cultural factors underpin the recommendation for in-situ support of the two populations separately. While ex situ conservation strategies can be applied at an integrated level, with due consideration of shared genetic background and unique variation in both breeds. The various approaches and indicators used in this study highlight the complexity of conserving local endangered sheep breeds. Rather than developing conservation strategies for individual breeds, the results suggest that it may be more effective to design strategies for clusters of breeds. As the aim is to use financial and institutional resources to optimize conservation efforts for clusters of local breeds as efficiently as possible, it is essential to consider genetic diversity metrics and phenotypic and socio-cultural aspects simultaneously.

Keywords: 2026

How to Cite:

Hoorneman, J., Huisman, J., Schoon, M., ten Napel, J. & Windig, J., (2026) “Conservation strategies for local Dutch sheep breeds: combining (genomic) diversity indicators”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286606. doi: https://doi.org/10.31274/wcgalp.24062

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