Oxidative Stress-Related Semen Quality and Fertility in the Male Arabian Yellowfin Sea Bream (Acanthopagrus arabicus) Fed a Selenium Nanoparticle-Supplemented Plant Protein-Rich Diet

Abstract

A three-month research was conducted to evaluate the influence of supplementing a plant protein- (PP-) rich diet (60% of fish meal (FM) was replaced with a mixture of alternative PP sources) with selenium nanoparticles (Se-N) on sperm kinetics, fertilization capacity, and antioxidative responses in Arabian yellowfin sea bream (Acanthopagrus arabicus) males. In this point, graded levels of Se-N at 0, 0.5, 1, 2, and 4 mg/kg were added to the PP-rich diet. Also, a FM-based diet was used as a positive control. Two hundred and eighty-eight brooders (males: 195.3±10.8 g and females: 237.5±8.1 g; mean±standard error) were randomly distributed into eighteen 10 m3 rectangular concrete tanks (8 males: 8 females in each tank), and every three tanks were fed with one of the experimental feeds for three months. The seawater temperature and salinity were 18-22°C and 40-41‰, respectively, during the husbandry period. Selenium retention increased in the liver, testes, and semen of males with increasing dietary Se-N level (P<0.05). Sperm density in fish fed with 2 mg Se-N/kg PP-rich diet (42.1×109/mL) was higher than those fed control, 0, 0.5, and 1 mg Se-N/kg PP-rich diets. The percentages of sperm motility in 60 s and 300 s after activation, sperms with straight movement, the longevity of sperm motility, and fertilization rate increased with increasing Se-N level in the PP-rich diets (P<0.05). The highest and lowest semen superoxide dismutase activities were in fish fed 4 and 2 mg Se-N/kg PP-rich diets, respectively. The highest glutathione peroxidase activity in semen was in fish fed 4 mg Se-N/kg PP-rich diet, and the lowest values were in fish fed 0 and 0.5 mg Se-N/kg PP-rich diets. Total antioxidant capacity values in semen of fish fed 1 and 4 mg Se-N/kg PP-rich diets were higher than the other treatments. Fish fed with PP-rich diet without any Se-N supplementation had higher malondialdehyde level in the semen compared to the other groups. Results showed that supplementing PP-rich diet with 2-4 mg Se-N/kg can improve sperm kinetics and enhance fertility potential in A. arabicus males.