Abstract

Characterization studies of local livestock breeds are important to identify their potential and value for the Global Animal Genetic Resources. Important traits have been attributed to local breeds including adaptability and resilience to harsh environments and other traits with potential use in breeding schemes oriented towards the challenges of climate change. The aim of this thesis was to generate baseline information for the development of future conservation and breeding programs for the Creole cattle in Bolivia. For this purpose, three Creole cattle populations were included in this study: the Chaqueño (CHA), the Saavedreño (CEASIP) and a population from Pasorapa (PASO).

In the first part of this thesis, the main characteristics of the production and management system in Pasorapa were described. Further, the identification and evaluation of elements affecting the sustainability of the production system and the development of breeding and conservation programs was done. Open-ended and closedended questionnaires and interviews with 81 smallholders from 11 communities from Pasorapa were performed. Poor infrastructure and deficient health management practices were found. The rearing system based on two stages with animals released in the mountains for about 7 months of the year and feeding mainly of native plant species, showed a strong interaction between the cattle and the environment. Farmer perceptions about diseases, mortality causes and selection criteria were described, showing that additionally to body conformation, farmers considered coat color for selection of breeding and replacement animals. Productivity, income and ecosystem services were identified as the main factors affecting the sustainability of the system.

In the second part of this study, the population structure, genetic diversity, linkage disequilibrium (LD) and ROH based inbreeding levels of the three cattle populations were assessed using a 50K SNP array. Pairwise FST values indicated low to moderate differentiation between populations. Admixture analysis showed clear signs of admixture among and within populations. CEASIP had the highest proportion of ROHs for the length classes 4-8 Mb, 8-16 Mb and >16 Mb. FROH coefficient values were higher for CHA and CEASIP populations for the >4 Mb and >16 Mb length classes indicating past and recent inbreeding. PASO had the lowest inbreeding coefficients for all ROH length classes. LD and effective population size of PASO might have been influenced by recurrent bottleneck episodes. LD pattern in CEASIP indicated that a 50K SNP array could be applied for association studies in this population.

Keywords

creole; management; farmer perceptions; genetic diversity; linkage disequilibrium; inbreeding; Runs of Homozygosity

Published in

Acta Universitatis Agriculturae Sueciae
2020, number: 2020:7
ISBN: 978-91-7760-532-4, eISBN: 978-91-7760-533-1
Publisher: Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences

SLU Authors

• Bottani, Gabriela

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Genetics and Breeding
Environmental Sciences related to Agriculture and Land-use


Permanent link to this page (URI)

https://res.slu.se/id/publ/104353