The objectives of the present study have therefore been to compare the performances, the carcass yield and meat quality from local Tunisian poultry and fast-growing genotype (Arbor Acres). Local poultry and Arbor Acres were raised for 16 and 8 weeks respectively. The performances of local chickens were lower than those of the Arbor chickens under identical conditions (P<0.0001). They have a weight at 16 weeks (1249g) and a total DWG weak (10.81 g/d), whereas the Arbor have a BW at 8 weeks (2383g) and a total DWG (41.66 g/d). The growth rate for local chicken (K=0.156/w) is lower than for Arbor (K=0.354/w). The feed intake of concentrates during 16w by local chicken are comparable with the Arbor chicken at 8w (P>0.05) thus showing a good valorisation of the pasture by local chicken (14.4%). Feed conversion ratio (FCR) for local poultry was relatively high (3.97) and their livability of is comparable to the Arbor (P>0.0001), this shows well thermotolerance of local chicken and its rusticity (P<0.0001). The ultime pH after 24h of slaughtering was relatively high (6.1) for local poultry compared to Arbor (5.79) and color parameters in the main muscles were particularly intense for local poultry. The carcass of local poultry is thin and low in fat (P<0.0001).

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Sheep farming plays an important economic role, and it contributes to the livelihoods of many rural poor in several regions worldwide and particularly in Tunisia. Therefore, the steady improvement of ewes’ reproductive performance is a pressing need. The MTNR1A gene has been identified as an important candidate gene that plays a key role in sheep reproduction and its sexual inactivity. It is involved in the control of photoperiod-induced seasonality mediated by melatonin secretion. The aim of this study was to identify SNPs in the MTNR1A gene in two Tunisian breeds, Barbarine (B) and Queue Fine de l’Ouest (QFO). DNA extracted from the blood of 77 adult ewes was sequenced. Selected ewes were exposed to adult fertile rams. A total of 26 SNPs were detected; 15 SNPs in the promoter region and 11 SNPs in the exon II were observed in both (B) and (QFO) breeds. The SNP rs602330706 in exon II is a novel SNP detected for the first time only in the (B) breed. The SNPs rs430181568 and rs40738822721 (SNP18 and SNP20 in our study, respectively) were totally linked in this study and can be considered a single marker. DTL was associated with SNP18 and SNP20 in (B) ewes (p < 0.05); however, no significant difference was detected between the three genotypes (G/G, G/A, and A/A) at these two SNPs. Fertility rate and litter size parameters were not affected by SNP18 and SNP20. There was an association between these two polymorphisms and (B) lambs’ birth weights (p < 0.05). Furthermore, the ewes with the A/A genotype gave birth to lambs with a higher weight compared to the other two genotypes for this breed (p < 0.05). There was not an association between SNP 18 and SNP20 and (QFO) ewes’ reproductive parameters. These results might be considered in future sheep selection programs for reproductive genetic improvement.

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