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Investigating the genetic variability and structure of Moroccan sheep breeds will reveal crucial information for the conservation and management of this population. This study used 22 microsatellite markers to assess the genetic diversity among and within five Moroccan sheep breeds: Sardi (N = 35), Boujaad (N = 31), Timadhite (N = 35), Beni Guil (N = 35), and D’man_Morroco (N = 35). In the whole sample, a total of 299 alleles were detected. The five breeds showed a relatively high level of gene diversity ranging between 0.725 (D’man_Morocco) and 0.764 (Timahdite). The Analysis of Molecular Variance (AMOVA) indicated that variability among populations contributed only 3.64% of the observed genetic diversity. Wilcoxon tests of excess heterozygosity under the two-phase model (TPM) did not provide strong evidence for recent bottlenecks in the five studied breeds. Unrooted neighbour joining (NJ) tree for the modified Cavalli-Sforza chord distance ( D A ), pairwise multilocus estimates of an effective number of migrants (Nm) and the Bayesian clustering method cohesively revealed poor structure of genetic variation among breeds. Our results also show that in spite of the high level of phenotypic diversity in the Moroccan sheep breeds, the past breeding strategies could lead to genetic admixture occurring as a result of relatively high gene-flow among the breeds. [ABSTRACT FROM AUTHOR]

This study aimed to investigate Y chromosomal haplotypes in the main Tunisian sheep breeds. For this purpose, we sequenced 2 regions of SRY (549-bp and 598-bp fragments) and 1 region in each of the AMELY and DBY genes in Barbarin, Western Thin Tail, Sicilo Sarde, and Black Thibar breeds. In addition, we analyzed the diversity at the SRYM18 microsatellite locus and detected 4 alleles of 139, 141, 143, and 145 bp. The sequencing analysis did not reveal any polymorphism in the AMELY or DBY regions; however, 2 samples carried the G allele in the 549-bp fragment of SRY. A total of 5 haplotypes, H4, H5, H6, H8, and H12, were found in the 4 breeds. The most common haplotype was H8 (55.5%), followed by H6 (34.5%), while other haplotypes were observed at low frequencies. H4 and H5 haplotypes were observed only in Western Thin Tail and Black Thibar breeds, respectively. In spite of the small area of Tunisia, a high Y chromosome diversity was observed. The results underlined the genetic relation of Tunisian sheep breeds with Middle Eastern, African, and European sheep breeds. [ABSTRACT FROM AUTHOR]

Due to its geo-climatic conditions, Algeria represents a biodiversity hotspot, with sheep breeds well adapted to a patchwork of extremely heterogeneous harsh habitats. The importance of this peculiar genetic reservoir increases as climate change drives the demand for new adaptations. However, the expansion of a single breed (Ouled-Djellal) which occurred in the last decades has generated a critical situation for the other breeds; some of them are being subjected to uncontrolled cross-breeding with the favored breed and/or to marginalization (effective size contraction). This study investigated genetic diversity within and among six of the nine Algerian breeds, by use of 30 microsatellite markers. Our results showed that, in spite of the census contraction experienced by most of the considered breeds, genetic diversity is still substantial (average gene diversity ranging 0.68 to 0.76) and inbreeding was not identified as a problem. However, two breeds (Rembi and Taâdmit) appeared to have lost most of their genetic originality because of intensive cross-breeding with Ouled-Djellal. Based on the above evidence, we suggest Hamra, Sidaoun, and D’man as breeds deserving the highest priority for conservation in Algeria. [ABSTRACT FROM AUTHOR]