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8 result(s) for "Ben Abdelkader, Faten"
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The melittology research in Northern Africa and the Middle East: past and present situations
Background More than 20,000 species in the superfamily Apoidea have been identified worldwide. This superfamily includes the most important group of insect pollinators that contribute to the integrity of ecosystems. Main body We have gathered in this paper data from many previous works in Northern Africa and Middle East regions. Some of these data are date from many years ago and others are recent. We present here a non-exhaustive list of some common Apoid species. In addition, certain previous studies that were published and other current research opportunities were suggested. Conclusion Although there are many bee experts in the Arab world, i.e., in apiculture, however, a few researchers are interested in melittology even though it seems that this region represents a large bee diversity.
Toxicity assessment of chronic exposure to common insecticides and bee medications on colony development and drones sperm parameters
The effect of agrochemicals and beekeeping treatments on drones have not been widely investigated compared to workers or queens. In the present study, we investigated the chronic exposure of chemicals set (deltamethrin, acetamiprid, oxalic acid, fumagillin, and amitraz) on some sperm parameters and on the histomorphology of seminal vesicles. We also assessed the colony development and nosema load before and after the exposure. Thirty native Apis mellifera anatolica honeybee colonies with sister queens equalized with brood and total frame of bees were used for this experiment. Five colonies were used for each group. Deltamethrin, acetamiprid and fumagillin were given as oral chronic exposure at final concentrations of 25.10-6 mg L−1, 0.01 m L−1 and 50 mg L−1 respectively in syrup solution (50/50). Colonies were exposed to oxalic acid by spraying 5 mL per frame space of 3% (w/v) of oxalic acid dihydrate. Finally, the amitraz was applied based on the manufacturer’s instructions. The concentrations chosen represented the field-realistic concentrations and those used by beekeepers in the region. Results showed that deltamethrin reduced brood production. In the same group, we found a high increase in nosema load. All treatments decreased sperm count except for fumagillin but this compound increased sperm mortality and increased the percentage of sperm with defected acrosome integrity. The amitraz exhibited a high sperm mortality and high percentage of sperm with defected membrane integrity function. The sperm parameters such as the count, the motility, the acrosome integrity, the membrane function of sperm, and the histomorphology of seminal vesicles of drones exposed to oxalic acid were the most affected. Bee medications commonly used such as oxalic acid and fumagillin should be more investigated and should be considered by beekeepers and particularly queen breeders.
Drone exposure to the systemic insecticide Fipronil indirectly impairs queen reproductive potential
A species that requires sexual reproduction but cannot reproduce is doomed to extinction. The important increasing loss of species emphasizes the ecological significance of elucidating the effects of environmental stressors, such as pesticides, on reproduction. Despite its special reproductive behavior, the honey bee was selected as a relevant and integrative environmental model because of its constant and diverse exposure to many stressors due to foraging activity. The widely used insecticide Fipronil, the use of which is controversial because of its adverse effects on honey bees, was chosen to expose captive drones in hives via syrup contaminated at 0.1 μg/L and gathered by foragers. Such environmental exposure led to decreased spermatozoa concentration and sperm viability coupled with an increased sperm metabolic rate, resulting in drone fertility impairment. Subsequently, unexposed queens inseminated with such sperm exhibited fewer spermatozoa with lower viability in their spermatheca, leaving no doubt about the detrimental consequences for the reproductive potential of queens, which are key for colony sustainability. These findings suggest that pesticides could contribute to declining honey bee populations through fertility impairment, as exemplified by Fipronil. More broadly, reproductive disorders should be taken into consideration when investigating the decline of other species.
Nosema ceranae, Fipronil and their combination compromise honey bee reproduction via changes in male physiology
The honey bee is threatened by biological agents and pesticides that can act in combination to induce synergistic effects on its physiology and lifespan. The synergistic effects of a parasite/pesticide combination have been demonstrated on workers and queens, but no studies have been performed on drones despite their essential contribution to colony sustainability by providing semen diversity and quality. The effects of the Nosema ceranae/fipronil combination on the life traits and physiology of mature drones were examined following exposure under semi-field conditions. The results showed that the microsporidia alone induced moderate and localized effects in the midgut, whereas fipronil alone induced moderate and generalized effects. The parasite/insecticide combination drastically affected both physiology and survival, exhibiting an important and significant generalized action that couldjeopardize mating success. In terms of fertility, semen was strongly impacted regardless of stressor, suggesting that drone reproductive functions are very sensitive to stress factors. These findings suggest that drone health and fertility impairment might contribute to poorly mated queens, leading to the storage of poor quality semen and poor spermathecae diversity. Thus, the queens failures observed in recent years might result from the continuous exposure of drones to multiple environmental stressors.
Effects of temperature adjustment with a heating device in weak honey bee colonies in cold seasons
Temperature adjustment was used to buffer against changes in external environmental temperature by a heating device. Two groups of honey bee colonies Apis mellifera anatoliaca were used: one as experimental (20) and the other control (10), which were equalized in terms of the number of brood frames, frames with bees, food, hive materials, and health treatments. The experimental colonies were heated during the cold season, and the temperature and humidity inside the hive were recorded. The number of frames of brood, frames of bees, and Varroa destructor mite numbers were also determined for all hives. Results suggest that the number of brood frames and frames with bees increased significantly in the hives with the heating treatment. However, varroa mite numbers also increased significantly in the heated colonies in comparison to the control colonies. Colony losses were significantly less (15%) in heated colonies compared to a 40% loss in control colonies. This is the first account demonstrating that using simple heating devices can support weak colonies during the cold season in general, and colony losses can be reduced significantly from this heating treatment in cold seasons.
Drone exposure to the systemic insecticide Fipronil indirectly impairs queen reproductive potential
A species that requires sexual reproduction but cannot reproduce is doomed to extinction. The important increasing loss of species emphasizes the ecological significance of elucidating the effects of environmental stressors, such as pesticides, on reproduction. Despite its special reproductive behavior, the honey bee was selected as a relevant and integrative environmental model because of its constant and diverse exposure to many stressors due to foraging activity. The widely used insecticide Fipronil, the use of which is controversial because of its adverse effects on honey bees, was chosen to expose captive drones in hives via syrup contaminated at 0.1 μg/L and gathered by foragers. Such environmental exposure led to decreased spermatozoa concentration and sperm viability coupled with an increased sperm metabolic rate, resulting in drone fertility impairment. Subsequently, unexposed queens inseminated with such sperm exhibited fewer spermatozoa with lower viability in their spermatheca, leaving no doubt about the detrimental consequences for the reproductive potential of queens, which are key for colony sustainability. These findings suggest that pesticides could contribute to declining honey bee populations through fertility impairment, as exemplified by Fipronil. More broadly, reproductive disorders should be taken into consideration when investigating the decline of other species.
Adenocarcinoma of intestinal type arising in mature cystic teratoma of ovary: A diagnostic dilemma
Adenocarcinomas of intestinal type arising in mature cystic teratoma of ovary (MCT) are extremely rare and remain a diagnostic dilemma because of its similarities with MCT. Serum tumor markers CEA and SCC and also MRI may help in the preoperative diagnosis. Pathologist experience helps in intraoperative diagnosis. Adenocarcinomas of intestinal type arising in mature cystic teratoma of ovary (MCT) are extremely rare and remain a diagnostic dilemma because of its similarities with MCT. Serum tumor markers CEA and SCC and also MRI may help in the preoperative diagnosis. Pathologist experience helps in intraoperative diagnosis.
Necrotizing otitis externa: 19 cases’ report
Necrotizing otitis externa is an uncommon but severe infectious disease of the external auditory canal. Patients at risk are those immunodepressed or having diabetes. The causal germ is often Pseudomonas aeruginosa . Over a period of 10 years (1997–2006), we treated 19 patients: 94.7% had diabetes (insulin dependent in 6 cases). The causal germ was P. aeruginosa in 59% of cases. The pretherapeutic work-up included a computed tomography and a scintigraphy practiced in order to confirm diagnosis and assess the extension. Medical treatment was based on a parenteral antibiotic therapy using a third-generation cephalosporin and a fluoroquinolones. Local treatment of the auditory canal including cleaning and application of antimicrobial agents was performed in all the cases. Surgical debridement of soft tissue and infected bone was performed in one patient who did not respond to medical management. Repeated scintigraphies with gallium were used to follow the course under treatment in only three cases. We had a 89.4% cure rate with only three cases of recurrence. We reviewed the data in the literature on necrotizing otitis externa and present the important diagnostic, imaging, and therapeutic aspects of the disease.