ВИДОСПЕЦИФІЧНІ РОЗХОДЖЕННЯ ІНДУКОВАНИХ ДІАТОМОВИМИ АНОМАЛІЙ ЕМБРІОГЕНЕЗУ КАЛАНОЇДНИХ КОПЕПОД: ЧИ ЗВ'ЯЗАНІ ВОНИ ІЗ ЗАПАСНИМИ АНТИОКСИДАНТАМИ?

• Date: 2023
• Main Author: Ханайченко, А. М.
• Format: Article
• Language: English
• Published: Marine Ecological Journal 2023
• Subjects: каланоїдні копеподи; діатомові; ембріон; аномалії; экстраклітинний матрикс; пігмент
• Online Access: https://mej.od.ua/index.php/mej/article/view/641
• Journal Title: Marine Ecological Journal

Egg production and viability of co-occurring in nature copepods, Calanus helgolandicus and Calanoides carinatus, fed diatom, Thalassiosira rotula, and then switched to dinoflagellate Prorocentrum minimum, were compared in experimental conditions. Egg production of both species on diatom diet was similar (up to 17-22 eggs.female-1.d-1) but no viable nauplii were observed. Development was arrested at different stages depending on degree of anomalies. Abnormal embryos displayed various degrees of deteriorations in pigment distribution and organization of extracellular matrix. Reproductive responses of C.carinatus both to negative (diatom) and positive (dinoflagellate) diets were postponed in comparison with quick responses of C.helgolandicus. After 3 days of dinoflagellate diet C.carinatus still produced only abnormal embryos with strong residual effect of diatom diet, while C.helgolandicus produced 50 % of viable nauplii. Based on own and literature data, our hypothesis links degree of diatom-induced copepod embryonic anomalies to the disturbances in antioxidant properties of the membranes and the degree of lipid peroxidation in embryo membranes and cytoplasm attributed to imbalanced content and ratio of HUFAs and carotenoids from freshly assimilated diet. Species-specific differences in copepod reproductive responses to diatom feeding are supposedly related to different stock-piled material and pathways of these essential components to the late oocytes.