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Aquaculture Nutrtion
Hindawi
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Abstract: |
This trial aimed to investigate whether dietary selenium form influenced the reproductive performance of red tilapia broodfish.
Four experimental broodstock diets were prepared employing two types of selenium. The first diet was free of additives and acted as
the control diet. While the other three formulated diets were supplemented with conventional selenium sources (sodium selenite,
Na 2SeO 3; 1 mg/kg), selenium nanoparticles (NPSe, 1 mg/kg), or a combination of them (0.5 mg Na2 SeO3 /kg + 0.5 mg NPSe/kg),
respectively. Twelve cement ponds (each 24 m 2
) were subjected to fish brooder experimental groups. Each pond received six
prespawning females (mean initial weight, 60.9 Æ 0.4 g) and two males (mean weight 80.3 Æ 0.8 g) of red tilapia. Each formulated
diet was supplied to three broodfish cement ponds, and the reproductive traits of 18 adult female fish were monitored over
25 weeks. The findings showed that female fish fed NPSe-enriched diets had significantly higher viscera, liver, and gonad weight
than other experimental groups. At the same time, the highest levels of LH, progesterone, and estradiol-17β, as well as the lowest
levels of FSH, were detected in fish fed the NPSe diet, followed by those on the Na2SeO 3 + NPSe and Na 2SeO 3 diets, respectively.
Furthermore, the diameter, weight, and volume of eggs, as well as the number and weight of larvae in red tilapia brooder fish fed the
various dietary selenium forms, increased markedly (P <0:001). Female red tilapia broodfish given selenium-based diets enhanced
all spawning performance indicators (particularly total spawned egg per pond or fish and initial spawning interval) when compared
to a control group fed an unsupplemented diet. Besides, as compared to other treatment groups, the spawning frequency of each
female fish fed NPSe-supplemented diets (alone or in combination with Na 2SeO 3) was considerably (P <0:001) promoted. The fish
group fed NPSe alone or mixed with Na2SeO 3 had a well-developed stroma structure, many mature vitellogenic and postvitello-
genic oocytes, and a remarkable intensity of mature spermatozoa in the testis. In conclusion, incorporating NPse into red tilapia
broodstock diets might be a safe and efficient way to enhance reproductive function and fry production.
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