The status of cattle genetic resources in North Ethiopi: On-farm charcterization of six major cattle breeds

On-farm surveys and characterization of six indigenous north Ethiopian cattle breeds (Afar, Arado, Begait, Fogera, Medenes and Raya) was carried out with the objective of determining the current status of these breeds. Information from a structured questionnaire distributed to 450 farmers, 37 group discussions, field measurements of heart girth and height on 25 males and 25 females from each breed and secondary information were used to carry out the study. Population size of Arado breed increased by more than three fold between 1992 and 1999, while the Raya, Fogera and Begait population decreased by 57, 27 and 67%; between 1981 and 1999 respectively. Three distinctive types were identified within the Afar and Begait breeds with different adaptation and threat levels in relation to changes to the bio-physical and social environment. Overall production and reproduction performance of the breeds in the pastoral production system (Afar and Arado and Fogera breeds of the agro-pastoral and mixed crop/ livestock production systems respectively. Extinction probability for most of the breeds was high, the highest (0.67) being for the Begait breed. On the other hand, except for the initiative taken to evaluate, improve and conserve the Fogera breed at the Metekel and Andasa cattle breedin ranches, there are no institutionalized attempts towards improving and/ or conserving the other breeds

Analysis of genetic diversity and conservation priorities for six north Ethiopian cattle breeds

v2007okBEL/GD

Reduced genetic structure of north Ethiopian cattle revealed by Y-chromosome analysis

v2007okBEL/GD

Molecular anatomy of the cytoplasmic domain of bovine growth hormone receptor, a quantitative trait locus

Quantitative trait loci (QTL) studies have indicated growth hormone receptor (GHR) as a candidate gene affecting cattle milk yield and composition. In order to characterize genetic variation at GHR in cattle, we studied European and East African breeds with different histories of selection, and Bos grunniens, Ovis aries, Sus scrofa, Bison bison and Rangifer tarandus as references. We sequenced most of the cytoplasmic domain (900 bp of exon 10), 89 bp of exon 8, including the putative causative mutation for the QTL effect, and 390 bp of intron 8 for comparison. In the cytoplasmic domain, seven synonymous and seven non-synonymous single nucleotide polymorphisms (SNP) were identified in cattle. Three non-synonymous SNPs were found in sheep and one synonymous SNP in yak, while other studied species were monomorphic. Three major haplotypes were observed, one unique to African breeds, one unique to European breeds and one shared. Bison and yak haplotypes are derivatives of the European haplotype lineage. Most of the exon 10 non-synonymous cattle SNPs appear at phylogenetically highly conserved sites. The polymorphisms in exon 10 cluster around a ruminant-specific tyrosine residue, suggesting that this site may act as an additional signalling domain of GHR in ruminants. Alternative explanations for the persistent polymorphism include balancing selection, hitch-hiking, pleiotropic or sexually antagonistic fitness effects or relaxed functional constraints

Genetic diversity and admixture of indigenous cattle from North Ethiopia : implications of historical introgressions in the gateway region to Africa

v2012o

Molecular anatomy of the cytoplasmic domain of bovine growth hormone receptor, a quantitative trait locus

Quantitative trait loci (QTL) studies have indicated growth hormone receptor (GHR) as a candidate gene affecting cattle milk yield and composition. In order to characterize genetic variation at GHR in cattle, we studied European and East African breeds with different histories of selection, and Bos grunniens, Ovis aries, Sus scrofa, Bison bison and Rangifer tarandus as references. We sequenced most of the cytoplasmic domain (900 bp of exon 10), 89 bp of exon 8, including the putative causative mutation for the QTL effect, and 390 bp of intron 8 for comparison. In the cytoplasmic domain, seven synonymous and seven non-synonymous single nucleotide polymorphisms (SNP) were identified in cattle. Three non-synonymous SNPs were found in sheep and one synonymous SNP in yak, while other studied species were monomorphic. Three major haplotypes were observed, one unique to African breeds, one unique to European breeds and one shared. Bison and yak haplotypes are derivatives of the European haplotype lineage. Most of the exon 10 non-synonymous cattle SNPs appear at phylogenetically highly conserved sites. The polymorphisms in exon 10 cluster around a ruminant-specific tyrosine residue, suggesting that this site may act as an additional signalling domain of GHR in ruminants. Alternative explanations for the persistent polymorphism include balancing selection, hitch-hiking, pleiotropic or sexually antagonistic fitness effects or relaxed functional constraints