Sperm motility is an important character for the assessment of milt quality and indicator to the expected rate of fertilization. Many factors can affect the sperm motility, including nature of water used as sperm activator medium after stripping the milt from the male fish. The aim of this study was to gain motility to spermatozoa and improve sperm kinematic parameters by applying a non‐chemical method. The effects of magnetic field on samples of hatchery water exposed to magnetic field of 2.71, 4.51 and 8.11 mT for the duration of 12, 24 and 36 hours on Salmo trutta labrax sperm motility were investigated with computer‐assisted sperm analysis (CASA) system; 4.51 mT exposure for 36 hours (A2H3) was greater in motility kinematic parameters (p < 0.05) and progressive kinematic parameters (VAP, VSL and VCL) with values of (93.1244 ± 37.222, 88.6111 ± 36.137, 96.8378 ± 35.396 μm/s) and (102.9167 ± 32.546, 100.9767 ± 31.894, 105.8778 ± 30.401 μm/s) respectively. But there was no (p ≥ 0.05) in the slow phase just in the VCL parameter had (p ≤ 0.05) (35.8789 ± 39.127 μm/s) among other parameters. There was (p ≤ 0.05) in starting motility time until vibration point (s) for 4.51 mT in 12 hour (A2H1) (27.3333 ± 1.527 s), but total time of motility was greater for 4.51 mT in 36 hour (A2H3) with (p ≤ 0.05) (49.6667 ± 2.081 s) compared with other treatments.

This study was conducted to investigate the effects of Polyglycerol polyricinoleate, (PGPR; E-476) as a dietary emulsifier supplement with sunflower and linseed oil on zebrafish (Danio rerio) growth performance and feed utilization. The control diet included only fish oil whereas other experimental diets included 6% sunflower oil and linseed oil with and without PGPR at %0.06. A total of 180 zebrafish larvae were used in the experiment. At the end of the experiment, the whole body samples were taken for proximate and fatty acid analysis. The fish were fed diets that contained PGPR, S0%L0% (PGPR), S6%L0% (PGPR) and S0%L6% (PGPR), had higher values (p˂0.05) in final weight (557.1, 521.3 and 622 mg), weight gain (1982.83, 2129.5 and 2779.56%), specific growth rate (2.062, 2.099 and 2.272), digested lipids amount (127.23, 122.65 and 148.52 mg), feed conversion efficiency rate (1.683, 1.893 and 1.725), protein efficiency ratio (1.321, 1.181 and 1.31) and whole body lipid percentage (44.37, 37.9827 and 46.7063 %), respectively. The percentages of fatty acids in fish tissues that fed diet with PGPR diets, S0%L0% (PGPR), S6%L0% (PGPR) and S0%L6% (PGPR), were higher (p˂0.05); ΣSFAs (16.695, 12.732 and 14.672 %), ΣMFAs (17.748, 16.014 and 17.922%), and ΣPUFAs (9.926, 9.235 and 14.111%), respectively, which reflected a positive influence of the emulsifier on zootechnical performance variables. Briefly, the results suggest that dietary use of linseed oil with particularly PGPR appeared to be a better alternative to fish oil.