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Relation of gilthead seabream (Sparus aurata) seasonal reproductive activity to hematology, serum biochemistry, histopathology, and Brdt gene expression

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Abstract

This study aimed to find the relation of Sparus aurata (gilthead seabream) reproductive activities to some blood parameters as complete blood count, liver enzymes, some hormones related to reproduction process and microscopic findings of gonads, as well as expression of Bromodomain testis-specific gene. Eighty-eight sexually mature seabream were collected and investigated through the four seasons. Red blood cells were higher in autumn and spring. Hemoglobin was high in summer, MCV highest values ​​were seen in winter and summer, while MCHC was highest in summer. The values ​​of white blood cells increased significantly in spring, summer, and autumn compared with winter. The highest value of lymphocytes was recorded in spring and autumn. Eosinophil was recorded the highest value in the spring. The highest value of segmented neutrophils was recorded in summer. The highest value of band neutrophil was recorded in summer and winter. Alanine aminotransferase and aspartate aminotransferase showed high values in the winter. Luteinizing hormone (LH) was higher in females, males, and hermaphrodites during winter. Follicle-stimulating hormone (FSH) was higher in females during spring. The highest value of estradiol 17-β and progesterone was recorded in summer. The highest value of total testosterone was recorded in spring. Microscopically, ovaries were immature and inactive during spring and summer but well developed in autumn and winter. During spring and summer, testes were immature and began spermatogenesis process but well developed with the appearance of spermatids and spermatozoa during autumn and winter. The expression of Brdt was higher in testes than ovary. Brdt recorded high expression in autumn and spring than in summer and winter.

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Authors and Affiliations

  1. Department of Pathology, Faculty of Vet. Medicine, Suez Canal University, Ismailia, Egypt

    Salah M. Aly

  2. Department of Animal Production and Fish Resources, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt

    Safaa M. Sharaf

  3. Animal Wealth Development Department, Faculty of Vet. Medicine, Suez Canal University, Ismailia, Egypt

    Abeer A. I. Hassanin

  4. Aquatic Hatchery Production Department, Fish Farming and Technology Institute, Suez Canal University, Ismailia, Egypt

    Alaa Sh. Griesh

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  1. Salah M. Aly
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Contributions

Prof. Dr. Salah M. Aly: Conceived and designed research, analyzed data, interpreted results of experiments, edited and revised manuscript, and approved final version of manuscript

Prof. Dr. Safaa M. Sharaf: Contribute in the research design, analyzed data, interpreted results of experiments, edited and revised manuscript

Prof.Dr. Abeer A.I.Hassanin: Performed the gene expression analysis experiment, analyzed its data, interpreted results of the gene expression experiment, and edited and revised manuscript

Ms. Alaa Sh. Griesh: Performed experiments, analyzed data, prepared figures and tables, and drafted manuscript

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Correspondence to Abeer A. I. Hassanin.

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Aly, S.M., Sharaf, S.M., Hassanin, A.A.I. et al. Relation of gilthead seabream (Sparus aurata) seasonal reproductive activity to hematology, serum biochemistry, histopathology, and Brdt gene expression. Fish Physiol Biochem 47, 961–977 (2021). https://doi.org/10.1007/s10695-021-00955-4

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