Browsing by Author "Khedidji, Hassiba"

Now showing 1 - 4 of 4

Effect of heat stress on Apis mellifera intermissa and Apis mellifera sahariensis in laboratory controlled conditions: a physiological approach
(Taylor and Francis Ltd., 2024) Khedidji, Hassiba; Chellali, Meriem; Cherrered, Nawel; Ghaffar, Intissar; Ladjali-Mohammedi, Kafia; Mohammedi, Arezki
The effects of heat on honey bees have received attention in many subspecies. Nevertheless, some subspecies still remain unexplored. In this study, we investigate for the first time the effect of heat on two subspecies of honey bees endemic to Algeria, Apis mellifera intermissa which is adapted to the Mediterranean climate and Apis mellifera sahariensis, which is adapted to the hot climate of southwest Algeria. We tested the hypothesis that sahariensis is more tolerant to heat stress than intermissa. In two in-vitro tests, we reared workers of both subspecies at 4 temperatures (34 °C, 38 °C, 39 °C, and 40 °C). Then, we determined the hemolymph protein (HP) concentration, hypopharyngeal gland development (HPG), ovary development and survival. We found that the sahariensis had HPG more developed and less affected by heat than intermissa. Conversely, although intermissa had more (HP) at 34 °C, we found a significant increase in (HP) at 38 °C, 39 C° and 40 °C in intermissa than sahariensis. Although ovary development is greater in intermissa than sahariensis at 34 °C and greater at 34 °C than 38 °C, 39 °C and 40 °C, we did not record differences in ovary development between the subspecies at 38 °C, 39 °C, and 40 °C. Finally, in all conditions, sahariensis had a higher survival than intermissa.
Effects of pollen deprivation in groups of tellian (Apis mellifera intermissa) and saharan (Apis mellifera sahariensis) honey bees under controlled conditions
(MDPI, 2022) Khedidji, Hassiba; Abderrahmani, Khaled; Oulebsir-Mohandkaci, Hakima; Ladjali-Mohammedi, Kafia; Mohammedi, Arezki
Worldwide, honey bees are increasingly faced with periods of pollen scarcity, which can lead to nutritional deficiencies, especially of proteins and amino acids. These are essential for the proper functioning of the single organism and the colony. To understand how bees react to protein deficiency, under controlled conditions, we studied the effect of pollen deficiency on the main physiological parameters in two subspecies endemic of Algeria, Apis mellifera intermissa and Apismellifera sahariensis. Emerging workers of both subspecies were reared with two diets: one was pollen-fed, whereas the other pollen-deprived. Several physiological criteria were measured depending on the type of diet and subspecies: the survival of the bees, the amount of total protein in the hemolymph, hypopharyngeal glands development and the ovary development of workers. These last three parameters were assessed at three different ages (7, 14 and 21 days). At birth, sahariensis workers weighed more than intermissa. With the same protein diet, the average life expectancy of sahariensis was extended by 5.55 days compared to intermissa. Even if deprived of pollen, sahariensis lived longer than intermissa fed with pollen (p < 0.001). In the three age levels, the hypopharyngeal glands were more developed and less affected by pollen deficiency (p < 0.001) in sahariensis than in intermissa (p < 0.001). The total hemolymph protein was higher in intermissa than in sahariensis regardless of the diet, and was also higher in protein-fed than in deprived bees (p < 0.001). The ovaries developed more rapidly with a high proportion in intermissa than in sahariensis (p < 0.05) regardless of the diet, and was also higher in the bees fed with pollen than those deprived (p < 0.05). Pollen deficiency generates physiological alterations and modifications, the amplitude of which varied according to the subspecies of the bee studied
Etude en conditions contrôlées de l'effet de la carence en pollen et du stress thermique sur quelques critères physiologiques et comportementaux des deux races d'abeilles locales Apis mellifera intermissa et Apis mellifera sahariensis
(Université M'Hamed Bougara Boumerdès : Faculté des Sciences, 2024) Khedidji, Hassiba; Mohammedi, Arezki(Directeur de thèse)
La présente thèse examine les effets de la carence en pollen et du stress thermique sur la physiologie et le comportement des deux sous-espèces d'abeilles endémiques en Algérie, Apis mellifera intermissa et Apis mellifera sahariensis. L'objectif principal était de comprendre comment ces deux sous-espèces réagissent face à ces facteurs de stress, et de déceler les éventuelles variations interspécifiques. La méthodologie a nécessité la conduite de trois expériences en condition de laboratoire, où le couvain et les ouvrières des deux-sous-espèces étaient exposés à trois types de stress (la carence en pollen, le stress thermique et la combinaison des deux stress). Les paramètres mesurés incluaient quelques facteurs physiologiques comme la composition biochimique de l'hémolymphe, le poids des individus soumis au stress, le développement de leurs glandes hypopharygiennes et des ovaires, leur durée de vie ainsi que le taux d'émergence du couvain. Les résultats ont montré que chaque sous-espèce réagissait différemment face aux trois types de stress. Par rapport à A. m. intermissa, A. m. sahariensis démontrait une bonne tolérance à la carence en pollen, au stress thermique et aux deux stress présents à la fois. La plupart des indicateurs physiologiques (le développement des glandes hypopharyngiennes, le poids des individus, le taux d'émergence du couvain et la survie) étaient en faveur d'A. m. sahariensis, tandis qu'A. m. intermissa montrait clairement qu'elle avait une propension à développer ses ovaires quelles que soient les conditions expérimentales. En conclusion, ce travail offre une perspective essentielle qui permet d'améliorer notre compréhension des mécanismes physiologiques d'adaptation des abeilles aux changements climatiques, tout en soulignant la nécessité d'adopter une approche plus appropriée pour la sauvegarde et la valorisation des deux sous-espèces
Promising Algerian essential oils as natural acaricides against the honey bee mite Varroa destructor (Acari: Varroidae)
(Springer Nature, 2024) Hazam, Souad; Touati, Salem; Touati, Lounis; Saher, Liza; Khedidji, Hassiba; Ait Kaki, Sabrina; Chemat, Smain
Varroosis induced by Varroa destructor Anderson and Trueman represents the most pathogenic and destructive disease affecting the western honey bee, Apis mellifera. In this study, we investigated the acaricidal activity against the Varroa mite using essential oils (EOs) from the aerial parts of four autochthonous Algerian herbal species, namely Artemisia herba alba, Artemisia campestris, Artemisia judaica and Ruta montana. EOs were obtained by means of hydrodistillation and their composition was characterized by gas chromatography–mass spectrometry. The toxicity of the selected EOs toward V. destructor and A. mellifera adult honey bees was evaluated using the complete exposure method. The results indicate the predominance of davanone (66.9%) in A. herba alba, β-pinene (19.5%) in A. campestris, piperitone (68.7%) in A. judaica and 2-undecanone (70.1%) in R. montana EOs. Interestingly, the LC50 values coupled to bee mortality rates revealed that all tested oils exhibited significant acaricidal efficiency with selectivity ratio (SR) values of 10.77, 8.78, 5.62 and 3.73 for A. campestris, A. judaica, A. herba alba, and R. montana, respectively. These values were better than that of thymol (SR = 3.65), the positive control. These findings suggest that these EOs could be used as plant-derived veterinary acaricides to control varroosis in field conditions.