The Mediterranean Sea is one of the busiest areas worldwide in terms of maritime activity and fac... more The Mediterranean Sea is one of the busiest areas worldwide in terms of maritime activity and faces considerable anthropogenic disturbances, such as pollution by hydrocarbons and heavy metals. This study evaluated the environmental status of three sites on the Algerian coast using the annelid polychaete Perinereis cultrifera as a biomonitoring sentinel species. It included different reproductive parameters such as oocyte diameter, frequency distributions, sexual maturity index, biochemical quantitative parameters represented by the vitellogenins and vitellins, and a histological study of the coelome during the reproductive period. The results showed that the females collected from El-Kala (healthy site) have the highest diameter 304.1 ± 24.3 μm during April but the values were increased in Annaba 290.0 ± 21.0 μm and Skikda 245.3 ± 26.7 μm. Significant differences were observed between worms from the three study sites during the three months of the study. Moreover, the size-frequency indicated that a relatively high proportion of females containing mature oocytes was found in April in females collected at El-Kala 52.4%, 46.4% in females collected at Annaba and 36.7% in females collected at Skikda. In addition, regarding the sexual maturity index, the highest values were recorded in April (3.8, 2.9, and 1.9) at the El-Kala, Annaba, and Skikda study sites. However, the biochemical analysis demontrated that the highest mean concentration of vitellogenin was in females of El-Kala (5.3 ± 0.3 µg/mg of coelomic fluid) in April, and the lowest mean concentration was measured in females of Skikda (1.5 ± 0.2 µg/mg of coelomic fluid). Therefore, the highest mean concentration of vitellin was measured in females of El-Kala (4.4 ± 0.2 µg/mg of oocytes) in April, while the lowest mean concentration of vitellin was measured in females of Skikda (1.02 ± 0.2 µg/mg of oocytes) in May. Significant differences were observed between worms from the three sites during the three months of the study. Furthermore, histological observations revealed that oogenesis was asynchronous, with oocytes at different stages of vitellogenesis simultaneously present. The structure of the oocytes of females collected at El-Kala showed intense vitellogenic activity due to the presence of very dense yolk cells. In contrast, the oocytes of the females collected from the two polluted sites (Annaba and Skikda) were small, vitellogenesis presented low intensity, and yolk cells were less frequent at the periphery and less uniform at the cytoplasmic mass; the nucleus was smaller, indicating a slower vitellogenic activity. These observations confirm the previously obtained results.
This study was to assess the marine environment quality by hydrocarbon contamination along the ea... more This study was to assess the marine environment quality by hydrocarbon contamination along the east Algerian coasts using an approach based on biomarkers and hydrocarbon rate in the polychaete Perinereis cultrifera. Individuals were collected from two sites: Skikda considered as a polluted site and from El-Kala as a reference site. During this study two approaches have been maintained: the first was the analysis of physico-chemical parameters of the seawater, where no significant differences were recorded for temperature, salinity and DBO5, unlike the rate of dissolved O2, pH and oil content in the seawater. The second approach was devoted to measure the biomarkers activity of glutathione Stransferase as phase II enzyme in the polychaete P. cultrifera. This approach confirms that individuals from Skikda have been submitted to highly polluted environment.
With a view to using the centipede Eupolybothrus nudicornis as a bioindicator in biomonitoring pr... more With a view to using the centipede Eupolybothrus nudicornis as a bioindicator in biomonitoring programs we studied the effects of environmental pollution on the activity of the enzyme acetylcholinesterase (AChE) as neurotoxicity marker. Males and females were collected during the spring breeding season at two sites located in the eastern part of Algeria: Guelma (36°25’N, 7°25’E) and Annaba (36°52’ N, 7°45’ E). The Guelma site was considered as the healthy reference site as it was away from any source of pollution. On the other hand, the Annaba site was considered polluted due to the presence of an important steel complex. Individuals of both sexes from Annaba showed a lower brain AChE activity than those from Guelma which could probably be due to chemical pollutants from the steel complex. Moreover, as AChE is considered as an exposure biomarker of pesticides contamination, we tested the effect of a bisacylhydrazine ecdysteroid analog (RH-0345) used as insecticide on brain AChE acti...
Les Chilopodes et les Diplopodes présents au niveau de deux sites localisés dans le nord-est de l... more Les Chilopodes et les Diplopodes présents au niveau de deux sites localisés dans le nord-est de l’Algérie (site anthropisé d’Annaba et site naturel d’El Tarf) ont été étudiés par piégeage durant une année (juin 2006 à mai 2007). Au total 901 Chilopodes et 411 Diplopodes ont été récoltés. Les diversités spatiotemporelles des deux taxons ont été évaluées. Nos résultats suggèrent que les paramètres physico-chimiques édaphiques tels que le taux de limon, le pourcentage de matière organique ou le pH mais aussi les paramètres climatiques tels que le volume de précipitation et le taux d’hygrométrie qui en résulte ont une influence significative sur l’abondance et la répartition spatiale des Chilopodes et des Diplopodes avec une nette différence de comportement entre les deux taxons. L’estimation de l’intensité des perturbations introduites par l’homme influençant la diversité écologique des deux taxons indique que la région d’Annaba, qui est plus anthropisée que celle d’El Tarf, subit une ...
Marine biodiversity play a fundamental role in the ecology and functioning of benthic communities... more Marine biodiversity play a fundamental role in the ecology and functioning of benthic communities. The study of the structure of benthic macroinvertebrate peoples is an excellent tool for evaluating the impact of human activities on the ecological quality of lotic environments. However, little data is available on the diversity, structure and ecology of benthic macroinvertebrates of the Algerian east coast. The main purpose of this work is to present an inventory of the current faunistic data general at three sites of study in Algerian east coastline: El-Kala, Annaba and Skikda. After doing the morphometric analysis of all the individuals, this study allowed to the identification of several species of macroinvertebrates. The variations in the distribution of these macroinvertebrates at different sites are related to external factors (temperature, salinity, dissolved O 2), that would have an impact on the abundance of the species of marine fauna of the Algerian east coastline.
Chilopoda and Diplopoda, were studied in two areas located in north-eastern Algeria (anthropized ... more Chilopoda and Diplopoda, were studied in two areas located in north-eastern Algeria (anthropized site of Annaba and natural site of El Tarf). Pitfall traps were used to collect individuals during one year (June 2006 to May 2007). In total, 901 Chilopoda and 411 Diplopoda were collected. Spatio- temporal diversities were evaluated for the two taxa. Our results suggest that the soil physico-chemical edaphic parameters such as the quantity of alluvium, the proportion of organic matter or the pH but also climatic parameters such as the amount of precipitation and the relative humidity of air have a significant influence on the abundance and spatial distribution of Chilopoda and Diplopoda with a clear difference of behaviour between the two taxa. The estimation of the intensity of perturbation due to human activities influencing the ecological diversity of the two taxonomic groups studied indicated that Annaba area, which is more anthropized than that of El Tarf, loosed in terms of Chilo...
This is the first record of the Lessepsian polychaete Pseudonereis anomala Gravier, 1899 in the w... more This is the first record of the Lessepsian polychaete Pseudonereis anomala Gravier, 1899 in the western Mediterranean Sea, specifically in Skikda Bay, Algeria. The species was collected among rocks covered by algae at 0.5 m depth. A characterization of the species, as well as some ecological and distributional aspects are provided.
The aim of this study was to assess the marine environment quality along the east Algerian coasts... more The aim of this study was to assess the marine environment quality along the east Algerian coasts using an approach based on biomarkers in the polychaete Perinereis cultrifera. Individuals were collected from three sites (Skikda, Annaba and El-Kala) based on the level of pollution. The non urbanized site of El-Kala was considered as a healthy reference site. The biomarkers selected during this study were the activities of acetylcholinesterase as neurotoxicity marker, glutathione S-transferase as phase II enzyme and catalase as oxidative stress marker. The results show differences between sites compared with the reference samples. This approach confirms that individuals from Skikda and Annaba have been submitted to highly polluted environment. Individuals collected from Skikda show the highest reduction of the mean fresh weight, length and number of setigers as well as the highest inhibition or induction of enzyme activities indicating a highly contamination status.
Nereis falsa est une annelide polychete de la famille des Nereidides presente dans la region d... more Nereis falsa est une annelide polychete de la famille des Nereidides presente dans la region d'El-Kala sur le littoral Nord-Est algerien, mais dont la biologie de la reproduction en Algerie n'est pas connue. Des prelevements mensuels ont ete effectues entre janvier et decembre 2007. Les vers ont ete recoltes sur les fonds durs parmi les rhodophyceae apres epandage d'eau de Javel forcant les vers a quitter leurs abris. Des ponctions cœlomiques ont permis de decrire les differents stades de l'ovogenese. L'examen des ponctions cœlomiques de chaque individu femelle a montre un aspect homogene avec des ovocytes de diametres sensiblement egaux, la croissance ovocytaire est donc synchrone. De plus, l'etude de l'evolution du diametre moyen des ovocytes a permis de preciser le cycle sexuel femelle. Le diametre moyen des ovocytes matures est de 165 μm. Les premieres femelles matures apparaissent a la mi-juin et la periode de ponte s'etale jusqu'a la fin du ...
Polychaetous from Algeria are little studied, despite their importance, they comprise diverse, an... more Polychaetous from Algeria are little studied, despite their importance, they comprise diverse, and ecologically significant species, in the present study individuals of two Nereididea species, Perinereis macropus and Perinereis cultrifera were sampled on the rocky shores of Collo and Skikda Coasts, and were described for the first time with biometric measurements, morphological variations and reproduction aspects, in attempt to provide general information about this group from Algeria, necessary for other future works, especially those on marine biodiversity; we marked the absence of P. macropus at the second site, affected by pollution, as well as the difference between algae associated with each species; weight and size variables show differences intersites and among species; oogenesis is asynrochronous, mature oocytes occur during July and May for P. macropus and P. cultrifera respectively, and only adults of P. macropus show epitokal modifications, the semelparity character is o...
Four species of nereidid polychaetes, Peri ner eis cultrifera, P. macropus, Nereis falsa, and Pl... more Four species of nereidid polychaetes, Peri ner eis cultrifera, P. macropus, Nereis falsa, and Platy ner eis dumerilii, were identified during three years in four intertidal rocky shore sites (El-Kala, Annaba, Skikda and Collo) along the east coast of Algeria during the years 2011–2013. Species’ distribution fluctuated according to sites and season. Perinereis cultrifera was observed during most of the year, except in summer. Perinereis macropus was observed at El-Kala, Skikda and Collo mainly in late winter and early spring. Nereis falsa was observed during most of the year in El-Kala and Annaba; this species was also observed in Skikda in 2011 but then disappeared in the last two years of this study. Finally, the presence of P. dumerilii was noticed only in El-Kala for a few months (mainly in March and April). Perinereis cultrifera, P. macropus and P. dumerilii reproduce after acquiring the epitokous form between April and May, when surface seawater temperature starts rising. The...
De facon a etudier l'influence de deux analogues d'ecdysteroides (RH-0345 et RH-5992) et ... more De facon a etudier l'influence de deux analogues d'ecdysteroides (RH-0345 et RH-5992) et d'un mimetique de l'hormone juvenile (pyriproxyfen), utilises comme insecticides sur les predateurs de la faune du sol, nous avons utilise le Chilopode Eupolybothrus nudicornis en tant que modele biologique. Les quantites d'insecticides injectees ont ete determinees experimentalement au prealable de facon a ne pas entrainer la mort prematuree des individus. Les experiences ont ete realisees avec des individus matures mâles et femelles recoltes au printemps et en automne dans la region d'Annaba (Est algerien).
L'injection de 3,33 μg de tebufenozide (agoniste d'ecdysteroide) ou de 0,08 μg de pyripro... more L'injection de 3,33 μg de tebufenozide (agoniste d'ecdysteroide) ou de 0,08 μg de pyriproxyfen (mimetique d'hormone juvenile) a des mâles de Lithobius forficatus provoque l'apparition de figures d'activations nucleolaires au niveau des spermatocytes ainsi qu'une augmentation du nombre de cellules en degenerescence. Les ovocytes de femelles injectees avec ces composes presentent egalement des signes d'un metabolisme nucleolaire soutenu; cependant, ils ne montrent pas d'augmentation du nombre de figures de degenerescences. Ces resultats sont compares avec ceux obtenus apres injection des hormones naturelles et discutes en rapport avec la specificite de chacun des types cellulaires.
The polychaetes occupy a prominent place in the food chain. They are used as bioindicators of pol... more The polychaetes occupy a prominent place in the food chain. They are used as bioindicators of pollution of the marine environment. This work was carried out in order to assess the variations in activity of glutathione -S-transferase (GST) as an enzyme involved in the detoxification process and compare the diversity of polychaetes species between different study sites. The establishment of an inventory of Polychaeta allowed the identification of several annelid species. The estimated GST activity shows a low activity level at ElKala site and induction at the site of Skikda.
Seasonal changes in oocyte diameter and pollution biomarkers of the Polychaete Perinereis cultrif... more Seasonal changes in oocyte diameter and pollution biomarkers of the Polychaete Perinereis cultrifera (Nereididae, Polychaeta) were studied during twelve months from January to December 2012 in the east coast of Algeria. The samples were collected monthly at three sites: El-kala, a site far from any source of pollution, Annaba and Skikda, sites located near human and industrial wastes. The oocytes took away females are measured and the biomarkers selected during this study were the activities of acetylcholinesterase as neurotoxicity marker and glutathione S-transferase as phase II enzyme. The results show differences between sites compared with the reference samples the period of reproduction unroll in spring (April, May). This approach confirms that individuals from Skikda and Annaba have been submitted to highly polluted environment. Individuals collected from Skikda showed the highest reduction of diameter oocyte as well as the highest inhibition or induction of enzyme activities ...
Avec pour objectif d'utiliser l'annelide polychete Perinereis cultrifera en tant que bioi... more Avec pour objectif d'utiliser l'annelide polychete Perinereis cultrifera en tant que bioindicateur dans les programmes de biomonitoring au niveau de la cote est algerienne, nous avons etudie les variations d'activite des enzymes acetylcholinesterase (AChE) en tant que marqueur de neurotoxicite et glutathion S-transferase en tant qu'enzyme intervenant dans le processus de detoxication des xenobiotiques et dans la defense contre le stress oxydant au niveau de deux sites, l'un contamine par l'implantation d'un important complexe petrochimique (Skikda), l'autre, non urbanise, faisant partie d'un parc national (El-Kala) et constituant le site de reference sain. Nous avons egalement etudie des indicateurs de l'etat physiologique (contenu en glucides, lipides et proteines) et reproducteur (poids frais essuye moyen et diametre ovocytaire moyen) des femelles. Les activites AChE et GST des femelles provenant du site pollue ont ete respectivement stimule...
Three species of polychaetous annelids are commercially collected, as baits, from natural populat... more Three species of polychaetous annelids are commercially collected, as baits, from natural populations along the coast of Algeria. They are collected by semi-professional bait harvesters supplying a variety of local outlets and are used as bait by local fishermen. Bait harvesters commonly use bleaching liquid (10% in sea water) or a KMnO4 (0.5 to 1% in sea water) solution to force Perinereis cultrifera (Nereididae) individuals out of their algal mat. Hediste diversicolor (Nereididae) and Scolelepis squamata(Spionidae) are dug from intertidal mudflats and sandy beaches. Commercial prices and ways of utilization are given for each species. The necessity for the legislative establishment of a regulatory management plan for worm angling is demonstrated.
The polychaete Nereis falsa Quatrefages, 1866 is present in the area of El Kala National Park on ... more The polychaete Nereis falsa Quatrefages, 1866 is present in the area of El Kala National Park on the East coast of Algeria. Field investigations were carried out from January to December 2007 to characterize the populations' reproductive cycle, secondary production and dynamics. Reproduction followed the atokous type, and spawning occured from mid-June to the end of August/early September when sea temperature was highest (20-23°C). The diameter of mature oocytes was approximately 180 lm. Mean lifespan was estimated to about one year. In 2007, the mean density was 11.27 ind. m-2 with a minimum of 7.83 ind. m-2 in April and a maximum of 14.5 ind. m-2 in February. The mean annual biomass was 1.36 g m-2 (fresh weight) with a minimum of 0.86 g m-2 in December and a maximum of 2.00 g m-2 in June. The population consisted of two cohorts distinguishable from size frequency distributions. One cohort corresponded to the recruitment of 2006 and the other appeared during the study period in September 2007. The annual production of N. falsa was 1.45 g m-2 year-1 , and the production/biomass ratio was 1.07 year-1 .
The Mediterranean Sea is one of the busiest areas worldwide in terms of maritime activity and fac... more The Mediterranean Sea is one of the busiest areas worldwide in terms of maritime activity and faces considerable anthropogenic disturbances, such as pollution by hydrocarbons and heavy metals. This study evaluated the environmental status of three sites on the Algerian coast using the annelid polychaete Perinereis cultrifera as a biomonitoring sentinel species. It included different reproductive parameters such as oocyte diameter, frequency distributions, sexual maturity index, biochemical quantitative parameters represented by the vitellogenins and vitellins, and a histological study of the coelome during the reproductive period. The results showed that the females collected from El-Kala (healthy site) have the highest diameter 304.1 ± 24.3 μm during April but the values were increased in Annaba 290.0 ± 21.0 μm and Skikda 245.3 ± 26.7 μm. Significant differences were observed between worms from the three study sites during the three months of the study. Moreover, the size-frequency indicated that a relatively high proportion of females containing mature oocytes was found in April in females collected at El-Kala 52.4%, 46.4% in females collected at Annaba and 36.7% in females collected at Skikda. In addition, regarding the sexual maturity index, the highest values were recorded in April (3.8, 2.9, and 1.9) at the El-Kala, Annaba, and Skikda study sites. However, the biochemical analysis demontrated that the highest mean concentration of vitellogenin was in females of El-Kala (5.3 ± 0.3 µg/mg of coelomic fluid) in April, and the lowest mean concentration was measured in females of Skikda (1.5 ± 0.2 µg/mg of coelomic fluid). Therefore, the highest mean concentration of vitellin was measured in females of El-Kala (4.4 ± 0.2 µg/mg of oocytes) in April, while the lowest mean concentration of vitellin was measured in females of Skikda (1.02 ± 0.2 µg/mg of oocytes) in May. Significant differences were observed between worms from the three sites during the three months of the study. Furthermore, histological observations revealed that oogenesis was asynchronous, with oocytes at different stages of vitellogenesis simultaneously present. The structure of the oocytes of females collected at El-Kala showed intense vitellogenic activity due to the presence of very dense yolk cells. In contrast, the oocytes of the females collected from the two polluted sites (Annaba and Skikda) were small, vitellogenesis presented low intensity, and yolk cells were less frequent at the periphery and less uniform at the cytoplasmic mass; the nucleus was smaller, indicating a slower vitellogenic activity. These observations confirm the previously obtained results.
This study was to assess the marine environment quality by hydrocarbon contamination along the ea... more This study was to assess the marine environment quality by hydrocarbon contamination along the east Algerian coasts using an approach based on biomarkers and hydrocarbon rate in the polychaete Perinereis cultrifera. Individuals were collected from two sites: Skikda considered as a polluted site and from El-Kala as a reference site. During this study two approaches have been maintained: the first was the analysis of physico-chemical parameters of the seawater, where no significant differences were recorded for temperature, salinity and DBO5, unlike the rate of dissolved O2, pH and oil content in the seawater. The second approach was devoted to measure the biomarkers activity of glutathione Stransferase as phase II enzyme in the polychaete P. cultrifera. This approach confirms that individuals from Skikda have been submitted to highly polluted environment.
With a view to using the centipede Eupolybothrus nudicornis as a bioindicator in biomonitoring pr... more With a view to using the centipede Eupolybothrus nudicornis as a bioindicator in biomonitoring programs we studied the effects of environmental pollution on the activity of the enzyme acetylcholinesterase (AChE) as neurotoxicity marker. Males and females were collected during the spring breeding season at two sites located in the eastern part of Algeria: Guelma (36°25’N, 7°25’E) and Annaba (36°52’ N, 7°45’ E). The Guelma site was considered as the healthy reference site as it was away from any source of pollution. On the other hand, the Annaba site was considered polluted due to the presence of an important steel complex. Individuals of both sexes from Annaba showed a lower brain AChE activity than those from Guelma which could probably be due to chemical pollutants from the steel complex. Moreover, as AChE is considered as an exposure biomarker of pesticides contamination, we tested the effect of a bisacylhydrazine ecdysteroid analog (RH-0345) used as insecticide on brain AChE acti...
Les Chilopodes et les Diplopodes présents au niveau de deux sites localisés dans le nord-est de l... more Les Chilopodes et les Diplopodes présents au niveau de deux sites localisés dans le nord-est de l’Algérie (site anthropisé d’Annaba et site naturel d’El Tarf) ont été étudiés par piégeage durant une année (juin 2006 à mai 2007). Au total 901 Chilopodes et 411 Diplopodes ont été récoltés. Les diversités spatiotemporelles des deux taxons ont été évaluées. Nos résultats suggèrent que les paramètres physico-chimiques édaphiques tels que le taux de limon, le pourcentage de matière organique ou le pH mais aussi les paramètres climatiques tels que le volume de précipitation et le taux d’hygrométrie qui en résulte ont une influence significative sur l’abondance et la répartition spatiale des Chilopodes et des Diplopodes avec une nette différence de comportement entre les deux taxons. L’estimation de l’intensité des perturbations introduites par l’homme influençant la diversité écologique des deux taxons indique que la région d’Annaba, qui est plus anthropisée que celle d’El Tarf, subit une ...
Marine biodiversity play a fundamental role in the ecology and functioning of benthic communities... more Marine biodiversity play a fundamental role in the ecology and functioning of benthic communities. The study of the structure of benthic macroinvertebrate peoples is an excellent tool for evaluating the impact of human activities on the ecological quality of lotic environments. However, little data is available on the diversity, structure and ecology of benthic macroinvertebrates of the Algerian east coast. The main purpose of this work is to present an inventory of the current faunistic data general at three sites of study in Algerian east coastline: El-Kala, Annaba and Skikda. After doing the morphometric analysis of all the individuals, this study allowed to the identification of several species of macroinvertebrates. The variations in the distribution of these macroinvertebrates at different sites are related to external factors (temperature, salinity, dissolved O 2), that would have an impact on the abundance of the species of marine fauna of the Algerian east coastline.
Chilopoda and Diplopoda, were studied in two areas located in north-eastern Algeria (anthropized ... more Chilopoda and Diplopoda, were studied in two areas located in north-eastern Algeria (anthropized site of Annaba and natural site of El Tarf). Pitfall traps were used to collect individuals during one year (June 2006 to May 2007). In total, 901 Chilopoda and 411 Diplopoda were collected. Spatio- temporal diversities were evaluated for the two taxa. Our results suggest that the soil physico-chemical edaphic parameters such as the quantity of alluvium, the proportion of organic matter or the pH but also climatic parameters such as the amount of precipitation and the relative humidity of air have a significant influence on the abundance and spatial distribution of Chilopoda and Diplopoda with a clear difference of behaviour between the two taxa. The estimation of the intensity of perturbation due to human activities influencing the ecological diversity of the two taxonomic groups studied indicated that Annaba area, which is more anthropized than that of El Tarf, loosed in terms of Chilo...
This is the first record of the Lessepsian polychaete Pseudonereis anomala Gravier, 1899 in the w... more This is the first record of the Lessepsian polychaete Pseudonereis anomala Gravier, 1899 in the western Mediterranean Sea, specifically in Skikda Bay, Algeria. The species was collected among rocks covered by algae at 0.5 m depth. A characterization of the species, as well as some ecological and distributional aspects are provided.
The aim of this study was to assess the marine environment quality along the east Algerian coasts... more The aim of this study was to assess the marine environment quality along the east Algerian coasts using an approach based on biomarkers in the polychaete Perinereis cultrifera. Individuals were collected from three sites (Skikda, Annaba and El-Kala) based on the level of pollution. The non urbanized site of El-Kala was considered as a healthy reference site. The biomarkers selected during this study were the activities of acetylcholinesterase as neurotoxicity marker, glutathione S-transferase as phase II enzyme and catalase as oxidative stress marker. The results show differences between sites compared with the reference samples. This approach confirms that individuals from Skikda and Annaba have been submitted to highly polluted environment. Individuals collected from Skikda show the highest reduction of the mean fresh weight, length and number of setigers as well as the highest inhibition or induction of enzyme activities indicating a highly contamination status.
Nereis falsa est une annelide polychete de la famille des Nereidides presente dans la region d... more Nereis falsa est une annelide polychete de la famille des Nereidides presente dans la region d'El-Kala sur le littoral Nord-Est algerien, mais dont la biologie de la reproduction en Algerie n'est pas connue. Des prelevements mensuels ont ete effectues entre janvier et decembre 2007. Les vers ont ete recoltes sur les fonds durs parmi les rhodophyceae apres epandage d'eau de Javel forcant les vers a quitter leurs abris. Des ponctions cœlomiques ont permis de decrire les differents stades de l'ovogenese. L'examen des ponctions cœlomiques de chaque individu femelle a montre un aspect homogene avec des ovocytes de diametres sensiblement egaux, la croissance ovocytaire est donc synchrone. De plus, l'etude de l'evolution du diametre moyen des ovocytes a permis de preciser le cycle sexuel femelle. Le diametre moyen des ovocytes matures est de 165 μm. Les premieres femelles matures apparaissent a la mi-juin et la periode de ponte s'etale jusqu'a la fin du ...
Polychaetous from Algeria are little studied, despite their importance, they comprise diverse, an... more Polychaetous from Algeria are little studied, despite their importance, they comprise diverse, and ecologically significant species, in the present study individuals of two Nereididea species, Perinereis macropus and Perinereis cultrifera were sampled on the rocky shores of Collo and Skikda Coasts, and were described for the first time with biometric measurements, morphological variations and reproduction aspects, in attempt to provide general information about this group from Algeria, necessary for other future works, especially those on marine biodiversity; we marked the absence of P. macropus at the second site, affected by pollution, as well as the difference between algae associated with each species; weight and size variables show differences intersites and among species; oogenesis is asynrochronous, mature oocytes occur during July and May for P. macropus and P. cultrifera respectively, and only adults of P. macropus show epitokal modifications, the semelparity character is o...
Four species of nereidid polychaetes, Peri ner eis cultrifera, P. macropus, Nereis falsa, and Pl... more Four species of nereidid polychaetes, Peri ner eis cultrifera, P. macropus, Nereis falsa, and Platy ner eis dumerilii, were identified during three years in four intertidal rocky shore sites (El-Kala, Annaba, Skikda and Collo) along the east coast of Algeria during the years 2011–2013. Species’ distribution fluctuated according to sites and season. Perinereis cultrifera was observed during most of the year, except in summer. Perinereis macropus was observed at El-Kala, Skikda and Collo mainly in late winter and early spring. Nereis falsa was observed during most of the year in El-Kala and Annaba; this species was also observed in Skikda in 2011 but then disappeared in the last two years of this study. Finally, the presence of P. dumerilii was noticed only in El-Kala for a few months (mainly in March and April). Perinereis cultrifera, P. macropus and P. dumerilii reproduce after acquiring the epitokous form between April and May, when surface seawater temperature starts rising. The...
De facon a etudier l'influence de deux analogues d'ecdysteroides (RH-0345 et RH-5992) et ... more De facon a etudier l'influence de deux analogues d'ecdysteroides (RH-0345 et RH-5992) et d'un mimetique de l'hormone juvenile (pyriproxyfen), utilises comme insecticides sur les predateurs de la faune du sol, nous avons utilise le Chilopode Eupolybothrus nudicornis en tant que modele biologique. Les quantites d'insecticides injectees ont ete determinees experimentalement au prealable de facon a ne pas entrainer la mort prematuree des individus. Les experiences ont ete realisees avec des individus matures mâles et femelles recoltes au printemps et en automne dans la region d'Annaba (Est algerien).
L'injection de 3,33 μg de tebufenozide (agoniste d'ecdysteroide) ou de 0,08 μg de pyripro... more L'injection de 3,33 μg de tebufenozide (agoniste d'ecdysteroide) ou de 0,08 μg de pyriproxyfen (mimetique d'hormone juvenile) a des mâles de Lithobius forficatus provoque l'apparition de figures d'activations nucleolaires au niveau des spermatocytes ainsi qu'une augmentation du nombre de cellules en degenerescence. Les ovocytes de femelles injectees avec ces composes presentent egalement des signes d'un metabolisme nucleolaire soutenu; cependant, ils ne montrent pas d'augmentation du nombre de figures de degenerescences. Ces resultats sont compares avec ceux obtenus apres injection des hormones naturelles et discutes en rapport avec la specificite de chacun des types cellulaires.
The polychaetes occupy a prominent place in the food chain. They are used as bioindicators of pol... more The polychaetes occupy a prominent place in the food chain. They are used as bioindicators of pollution of the marine environment. This work was carried out in order to assess the variations in activity of glutathione -S-transferase (GST) as an enzyme involved in the detoxification process and compare the diversity of polychaetes species between different study sites. The establishment of an inventory of Polychaeta allowed the identification of several annelid species. The estimated GST activity shows a low activity level at ElKala site and induction at the site of Skikda.
Seasonal changes in oocyte diameter and pollution biomarkers of the Polychaete Perinereis cultrif... more Seasonal changes in oocyte diameter and pollution biomarkers of the Polychaete Perinereis cultrifera (Nereididae, Polychaeta) were studied during twelve months from January to December 2012 in the east coast of Algeria. The samples were collected monthly at three sites: El-kala, a site far from any source of pollution, Annaba and Skikda, sites located near human and industrial wastes. The oocytes took away females are measured and the biomarkers selected during this study were the activities of acetylcholinesterase as neurotoxicity marker and glutathione S-transferase as phase II enzyme. The results show differences between sites compared with the reference samples the period of reproduction unroll in spring (April, May). This approach confirms that individuals from Skikda and Annaba have been submitted to highly polluted environment. Individuals collected from Skikda showed the highest reduction of diameter oocyte as well as the highest inhibition or induction of enzyme activities ...
Avec pour objectif d'utiliser l'annelide polychete Perinereis cultrifera en tant que bioi... more Avec pour objectif d'utiliser l'annelide polychete Perinereis cultrifera en tant que bioindicateur dans les programmes de biomonitoring au niveau de la cote est algerienne, nous avons etudie les variations d'activite des enzymes acetylcholinesterase (AChE) en tant que marqueur de neurotoxicite et glutathion S-transferase en tant qu'enzyme intervenant dans le processus de detoxication des xenobiotiques et dans la defense contre le stress oxydant au niveau de deux sites, l'un contamine par l'implantation d'un important complexe petrochimique (Skikda), l'autre, non urbanise, faisant partie d'un parc national (El-Kala) et constituant le site de reference sain. Nous avons egalement etudie des indicateurs de l'etat physiologique (contenu en glucides, lipides et proteines) et reproducteur (poids frais essuye moyen et diametre ovocytaire moyen) des femelles. Les activites AChE et GST des femelles provenant du site pollue ont ete respectivement stimule...
Three species of polychaetous annelids are commercially collected, as baits, from natural populat... more Three species of polychaetous annelids are commercially collected, as baits, from natural populations along the coast of Algeria. They are collected by semi-professional bait harvesters supplying a variety of local outlets and are used as bait by local fishermen. Bait harvesters commonly use bleaching liquid (10% in sea water) or a KMnO4 (0.5 to 1% in sea water) solution to force Perinereis cultrifera (Nereididae) individuals out of their algal mat. Hediste diversicolor (Nereididae) and Scolelepis squamata(Spionidae) are dug from intertidal mudflats and sandy beaches. Commercial prices and ways of utilization are given for each species. The necessity for the legislative establishment of a regulatory management plan for worm angling is demonstrated.
The polychaete Nereis falsa Quatrefages, 1866 is present in the area of El Kala National Park on ... more The polychaete Nereis falsa Quatrefages, 1866 is present in the area of El Kala National Park on the East coast of Algeria. Field investigations were carried out from January to December 2007 to characterize the populations' reproductive cycle, secondary production and dynamics. Reproduction followed the atokous type, and spawning occured from mid-June to the end of August/early September when sea temperature was highest (20-23°C). The diameter of mature oocytes was approximately 180 lm. Mean lifespan was estimated to about one year. In 2007, the mean density was 11.27 ind. m-2 with a minimum of 7.83 ind. m-2 in April and a maximum of 14.5 ind. m-2 in February. The mean annual biomass was 1.36 g m-2 (fresh weight) with a minimum of 0.86 g m-2 in December and a maximum of 2.00 g m-2 in June. The population consisted of two cohorts distinguishable from size frequency distributions. One cohort corresponded to the recruitment of 2006 and the other appeared during the study period in September 2007. The annual production of N. falsa was 1.45 g m-2 year-1 , and the production/biomass ratio was 1.07 year-1 .
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