الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 201 |  |  |
| | | from | 201 | | |
Abstract
Applications of nanotechnology are diverse and can be found in many fields, including
agriculture, aquaculture, medicine, energy, and environmental science. In aquaculture, different
nanomaterials have been used to improve fish production, such as selenium nanoparticles
(SeNPs). Because SeNPs are so small in size, they can interact with DNA molecules inside
cells, leading to changes in the gene expression patterns. This study examined the impacts of
different levels of SeNPs as a metabolic regulator on growth performance, survival analysis,
hematological and biochemical profiles, immune response, antioxidant capacity, gene
expression levels, and histometric parameters of skeletal muscles of Oreochromis niloticus. A
total of 180 monosex Nile tilapia fingerlings were randomly divided into three groups: control
group, treatment 1 (T1), and treatment 2 (T2). SeNPs were added to the diet at different levels
of 0.0 (control), 0.7 (T1), and 1.0 (T2) mg/kg diet. For six weeks, fish were fed the
experimental diet up to apparent satiation twice daily. At the end of the experiment, the treated
and control fish were anesthetized using sodium bicarbonate-buffered tricaine methanesulfonate
(buffered MS-222). All fish in the treated and control groups were counted and weighted
individually to obtain growth parameters and survival analysis. Furthermore, blood samples
were collected for hematological and biochemical examinations. Also, skeletal muscle samples
were collected for gene expression analysis, total RNA was extracted, reverse transcribed, and
real-time PCR was performed. Histological sections were prepared, examined, and analyzed.
The results indicated that the growth indices, FCR, and survival time were significantly
enhanced (P < 0.05) by adding SeNPs 1.0 mg/kg diet. Also, the haemato-biochemical
parameters, immune response, and antioxidant capacity of the fish were significantly improved.
Gene expression levels of GHR, MSTN, and MYOG were induced and the expression level of
MYF6 was decreased by adding SeNPs 1.0 mg/kg diet. Furthermore, the SeNPs (1.0 mg/kg
diet) increased the size of myofibers. In conclusion, dietary supplementation of Nile tilapia with
SeNPs induces significant effects that improve growth performance, survival time, blood health,
biochemical parameters, immunological and antioxidant response, expression of growth-related
genes, and histomorphology of myofibers. The results of the present study anticipate that
nanotechnology may play a principal role in the development of optimally formulated nanofeed supplements, including SeNPs as aquafeed additives and other micronutrients, to improve
fish growth and production.