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The alien blue swimming crab, Portunus segnis (Forskål, 1775), an Indo-Pacific species, has been recorded in the southern Mediterranean Sea for decades, and its occurrence along the southern Tunisian coasts has been recorded since 2014. The feeding habits of P. segnis were studied in the Gulf of Gabes from October 2015 to September 2016. The stomach contents of 3061 crabs, ranging from 50 to 168 mm carapace width, were analysed. The stomach contents appeared to consist mainly of large quantities of crustaceans, fish and molluscs, and small quantities of echinoderms, annelids, tunicates, cnidarians, plants, unidentifiable matter and debris. The major food groups observed were crustaceans throughout the year with fish and molluscs secondly. In juvenile, sub-adult and adult crabs, crustaceans constituted the dominant food source and these were present in more than 65% of the stomachs analysed. Ingestion of fish increases as the crab matures. A significant difference (P < 0.05) was observed in the quantity of the food consumed by the two sexes. The diet also increased with increasing ovary maturity degree, while the percentage of empty stomachs in ovigerous and non-ovigerous females did not show any difference. The vacuity index varied significantly in both sex (P < 0.0001), among size (P < 0.0001) and seasons (P < 0.0001). This study shows that, despite the diversity in blue crab diets and feeding habits, it is omnivorous with a preference for animal material.

The blue swimming crab Portunus segnis (Forskål, 1775) is one of the earliest Lessepsian invaders of the Mediterranean Sea, and is recorded since decades in various areas of the Mediterranean. Its presence in the southeastern Tunisian coasts (Gulf of Gabes) is, however, very recent. Allometry, condition factor and growth of P. segnis were studied along the Gulf of Gabes coasts. Sampling was performed by artisanal fishing gears as well as trawl net during a one-year period (October 2015 to September 2016) as processed 4971 crabs were collected. The crab carapace width (CW) ranged from 45 to 168 mm for males and 50 to 159 mm for females. The crab carapace length (CL) was 22.02-89.20 mm and 38.70-85.28 mm, respectively for males and females. The carapace width-carapace length, carapace width- front, carapace width-carapace height and carapace width-weight relationships were studied in separate sexes of crab. The covariance analysis indicates a significant difference between the two sexes with respect to the carapace width-carapace length and the carapace width-weight relationships. The condition factor ranged between 0.0042 and 0.0118 with a mean of 0.0078. The condition factor decreased with increasing crab size. The Von Bertalanffy growth parameters CW∞, K and t0 were estimated on the basis of Length-frequency modal progression analysis methods. The mean values of L∞ (mm), K (year-1) and t0 would be, respectively, 206.48 mm, 1.34 and -0.130 for males; 183.89 mm, 1.42 and -0.127 for females and, 190.60 mm, 1.02 and -0.177 for combined sexes.

The diet and feeding habits of the sharpsnout seabream, Diplodus puntazzo, from the Gulf of Gabès were investigated using stomach contents of 490 specimens ranging from 12.6 cm to 26.1 cm total length in size and from 29.95 g to 230.83 g in weight collected from commercial catches between April 2008 and March 2009. Of the total number of examined stomachs, 279 were empty (%VI = 56.94). This percentage varied significantly with months, attaining a maximum in spring (74.88%) and a minimum in autumn (37.38%). Eight major taxa were identified (Plantae, Spongia, Tunicata, Echinodermata, Crustacea, Annelida, Mollusca and Teleostei) in stomach contents of D. puntazzo. Plants were the most important food source, constituting 89.88% of the total Index of relative importance. The other groups, such as teleosts, molluscs, crustaceans and annelids represented accessory food. Significant differences in diet were observed in relation to season. Plants were the most important food source item in all seasons, especially during the autumn. The estimation of trophic level gave an average of 2.57 ± 0.2 for the whole population of D. puntazzo in the Gulf of Gabès. Based on the composition of its diet, this species may be considered as an omnivorous fish with a preference for vegetable material, and showing specialist feeding strategy.

Hepatitis B virus (HBV) is the main cause of diseases liver related infecting more than 200 milion persons worldwide. HBV infection shows high level of prevalence in South-East Europe and in Mediterranean basin. In Tunisia, a country with an intermediate level endemicity, HbsAg prevalence ranges from 2 to 5%. Most of the HBV isolates from Tunisia were classified as subgenotype D7 whose circulation is restricted to a specific area of North Africa including Maghreb region. In this paper, the phylogeny of HBV-D7 isolated from 38 Tunisian patients was investigated by analyzing the S gene region of HBV. A Bayesian coalescent-based framework was used to estimate the origin of the HBV-D7 in the country. The Tunisian D7 isolates were found to share a common ancestor whose origin was traced back to 1958. Population dynamics indicated that HBV-D7 epidemic in Tunisia grew exponentially from 1960s to 1990s. After that, the curve reached a plateau around the years 2000 likely due to the implementation of the infant vaccination program in 1996. Epidemiological data suggested that the exponential growth phase was likely sustained by intra-familial transmission events occurring during infancy. Further characterization of HBV-D7 isolates should be performed to evaluate, in the post-vaccination era, the emergence of new transmission routes, and to monitor the efficacy of the vaccination program. J. Med. Virol. 89:469-475, 2017. © 2016 Wiley Periodicals, Inc.

Le kyste hydatique cardiaque est une maladie parasitaire rare. Nous rapportons 45 cas de patients ayant des kystes hydatiques du coeur. 33 des 45 avaient un kyste cardiaque primitif et unique. Dix-huit patients dans notre serie etaient asymptomatiques alors que 27 se sont plaints de symptomes (dyspnee, douleur thoracique et palpitations). Dans Il cas, le kyste s'etait declare par une complication aigue. Trois des 11 avaient une hydatidose pulmonaire metastatique. Le diagnostic etait base sur un faisceau d'arguments dans lequel serologie et imagerie (echocardiographie, tomodensitometrie et imagerie par resonance magnetique) ont joue un role predominant. La kysto-perikystectomie est le «gold standard » mais elle n'est pas toujours possible a tous les sites. Dans ces cas, une approche conservatrice (kystectomie partielle) est obligatoire pour preserver la fonction cardiaque. Le taux de mortalite operatoire est de 5.5%. Deux recidives pericardiques ont ete observees pendant la periode de suivi.