ABSTRACT. The genetic diversity and genetic relationship of the two main groups of African sheep, thin-tailed and fat-tailed sheep, represented by the indigenous Tunisian sheep breeds "Barbarine" (BAR, fat-tailed) and "Queue Fine de l'Ouest" (QFO, thin-tailed) were investigated. The genotypes of 110 animals belonging to these two breeds and their crossbreed (CRO) were assessed using 17 microsatellite markers. The results showed high levels of genetic diversity and a total of 256 alleles were identified in the whole population. The mean values of observed and expected heterozygosity were 0.719 and 0.789, respectively, and the mean allelic richness estimate was 10.89. values over all loci indicated a notable level of inbreeding within the whole population. However, the F ST value (0.007) showed a low level of genetic differentiation between these two native breeds. The high level of both gene flow and molecular coancestry coefficient detected between the two breeds and their CRO revealed an old miscegenation between the BAR and QFO breeds. The clustering analysis performed with the STRUCTURE software confirmed gene flow between these two breeds. Results arising from this study provide evidence regarding the genetic structure and variability of the two main local sheep breeds, and the implications of their actual management, which indicates the need for an urgent conservation strategy in order to prevent significant gene flow and preserve the remaining breed specificity for future generations.

In this study, the genetic relationship and the population structure of western Mediterranean basin native sheep breeds is investigated, analyzing Maghrebian, Central Italian, and Venetian sheep with a highly informative microsatellite markers panel. The phylogeographical analysis, between breeds’ differentiation level (Wright’s fixation index), gene flow, ancestral relatedness measured by molecular coancestry, genetic distances, divergence times estimates and structure analyses, were revealed based on the assessment of 975 genotyped animals. The results unveiled the past introduction and migration history of sheep in the occidental Mediterranean basin since the early Neolithic. Our findings provided a scenario of three westward sheep migration phases fitting properly to the westward Neolithic expansion argued by zooarcheological, historical and human genetic studies.

In order to deal with the effects of globalization, urbanization, increase in world population, global warming, and climate change; and according to the Sustainable Development Goals (SDG) 2 targets, which aim to end hunger, achieve food security and improved nutrition and promote sustainable agriculture, it is urgently needed to transform our agriculture and livestock farming systems by taking into account the environmental considerations. The Breeding and management practices of indigenous bovine breeds: Solutions towards a sustainable future (BOVISOL) project is a scientific cooperation between three Mediterranean countries (Greece, Tunisia and Algeria) supported and funded by the European Commission under the European Research Area Networks (ERA-NET) scheme of the 7th Framework Programme. This project has been formed around the hypothesis that the local bovine breeds must be preserved since they possess a valuable genetic pool, and they are a part of the landscape and the biodiversity of rural areas. Moreover, their products (milk, cheese, meat, etc.) could contribute significantly to the local economies as they could easily be associated with recent food trends like “local” and “slow food”, which are considered today, as, not only a mean of nutrition, but also a way of living and a part of people’s identity. BOVISOL project aims to: (i) identify the local breeds and populations in a national level, (ii) describe the existing farm and breeding practices, (iii) analyze the quality of the main local animal products, (iv) propose solutions that will promote the sustainability of the traditional farming systems, especially nowadays that climate change proposes new challenges on animal production, and (v) disseminate the solutions on all the levels of the sector (farmers, scientists, local communities, governmental agencies).

This study analyzed the genetic variability, inbreeding and population structure of the Tunisian–North African dairy sheep breed, the Sicilo-Sarde (SS), created by crossing the Sarda and Comisana dairy breeds. The level of variability in the SS, considered as an endangered breed after a dramatic decrease, was assessed using 17 microsatellite markers by analyzing the two breed populations sampled from their respective cradles: SS of Beja (SSB, n = 27) and SS of Mateur (SSM, n = 25). High levels of genetic diversity in SS were revealed, with a total of 212 alleles, a high mean number of alleles (12.47 ± 4.17) and a high average polymorphism information content (PIC) (0.81 ± 0.10). The observed heterozygosity was considerable in SSB and SSM (0.795 and 0.785, respectively). The inbreeding level measured by the population inbreeding coefficient FIS is higher in the SSM population (0.121) than in the SSB population (0.090). The higher genetic diversity level detected in SSB reflected the effect of new Italian Sarda genes introduced by intra-uterine artificial insemination recently practiced in this population. The Wilcoxon test and the mode-shift distribution indicated that the SS breed is a non-bottlenecked population. The structural analysis reflected the historical miscegenation practiced during breed creation and highlighted further ancient miscegenation, which could date back to the introduction of the first sheep wave introduction to the western Mediterranean. Microsatellite markers were successfully applied in the assessment of the genetic variability of SS and should be used in monitoring this variability during the application of conservation strategies.

Non-commercialized sheep breeds known as local or native breeds are well adapted to their environmental constraints and constitute precious genetic resources that need prioritization for genetic diversity characterization and preservation. The aim of the present study was to assess the genetic diversity level and the related preservation decisions of very old and traditional native Mediterranean sheep breeds from Tunisia and Italy using 17 microsatellite markers. In total, 975 sheep were sampled from five Tunisian, one Center Italian, and four Venetian native breeds. Both private and publicly available farms were considered for each breed for breeding strategies’ comparison purposes. The microsatellite set used was highly informative (PIC = 0.80 ± 0.08), with a total of 383 alleles. Moderate genetic differentiation was revealed between the native sheep of the two Mediterranean sides (global overall loci FST = 0.081). The genetic diversity level was higher in the case of the Tunisian native breeds compared to the Italian ones, as evidenced by higher mean allelic richness, higher expected and observed heterozygosities, and lower inbreeding levels. Priority for conservation suggestions was carried out for each private or public breed population based on the contribution of each population to the diversity of the whole data. The four Venetian breeds, already undergoing conservation, the Tunisian dairy breed, and the very ancient Maghrebian breed, would be favored for conservation. In conclusion, our results highlighted the importance of the analyzed Mediterranean native sheep breeds as valuable inherited genetic reservoirs and supported previous conservation decisions made for the threatened breeds.

The indigenous cattle populations are threatened by extinction in many countries of the Mediterranean area. The objective of this study is the analysis of local cattle breeds’ production systems in Algeria, Greece, and Tunisia and the identification of their future challenges and opportunities. A total of 385 surveys were conducted in these study areas: central and northern Greece (43); northern and northwestern Tunisia (167), and northeastern Algeria (175). Data collected concerned socio-economic parameters as well as the production system’s functionality, constraints, and opportunities. Results revealed an average farmers’ age of 52.6 years old. The illiteracy rate is high, especially in Algeria (39%) and Tunisia (44%), where the farm size is relatively small with an average of 14 and four animals per farm, respectively. In Greece, much higher numbers were recorded (89 animals/farm). The average cultivated feedstuffs’ area is larger in Greece (12.07 ha) and smaller in Algeria and Tunisia (6.11 and 2.88 ha, respectively). Feeding resources are based on rangelands. Farming systems are traditional extensive and complemented when needed. Milk and meat marketing vary throughout countries and are not well valorized. The main constraints are high feeding costs, low milk and meat prices, and absence of labeling. Local and local-crossbred bovine populations could be valorized based on their good adaptation criteria when applying convenient genetic and development strategies.