Within the field of the aquaculture industry, tilapia stands out as one of the most widely farmed species globally due to its rapid growth, adaptability, and resilience. However, the intensification of farming systems has increased its susceptibility to stress and diseases, highlighting the importance of optimal nutrition to ensure efficient fry production.
A recent study published in Aquaculture Reports by researchers from King Faisal University, Suez Canal University, Zagazig University, the National Institute of Oceanography and Fisheries (NIOF), Princess Nourah bint Abdulrahman University, and Arish University explores the potential of date palm pollen (DPP) as a dietary supplement to enhance the reproductive capacity of hybrid red tilapia (Oreochromis niloticus × O. mossambicus).
The challenge: optimizing tilapia reproduction
Reproduction is a fundamental physiological process in the aquaculture value chain, as it directly contributes to the production of juveniles required for aquaculture activities. Optimizing red tilapia reproduction involves providing suitable dietary supplements to improve health and immunity, particularly during prolonged reproductive cycles.
To address reproductive challenges in tilapia aquaculture, researchers have been exploring natural feed additives that can enhance reproductive performance, immune function, and overall fish health.
One such additive is date palm pollen (DPP), derived from the male flowers of the date palm (Phoenix dactylifera).
What is Date Palm Pollen (DPP)?
Date palm pollen (DPP), obtained from the male flowers of the date palm (Phoenix dactylifera L.), is a nutrient-rich natural resource with potential as a valuable dietary supplement. This plant is native to tropical and subtropical regions of Africa and South Asia, and DPP has been traditionally used in the Middle East, particularly in Egypt and Saudi Arabia.
DPP is considered a functional and naturally active dietary supplement due to its remarkable content of bioactive compounds such as flavonoids, phenolics, and volatile unsaturated fatty acids. These compounds serve vital functions as antimicrobials, anti-inflammatories, antioxidants, and antitumor agents. DPP has been used for its health benefits and is widely employed as a dietary supplement in mammals.
GC-MS analysis of DPP revealed the presence of several bioactive compounds, including butan-1-one, tetradecanoic acid, cholestan-3-one, octasiloxane, and heptasiloxane. Various studies have reported that these compounds exhibit promising antimicrobial, antioxidant, and immunomodulatory properties.
The Study: How DPP enhances tilapia reproduction
The study evaluated the effects of dietary DPP administration on blood biochemistry, reproductive hormone levels, digestive enzyme activity, gonadal histology, reproductive performance, and the expression of reproduction-related genes in broodstock hybrid red tilapia (Oreochromis niloticus × O. mossambicus).
In the experiment, a group of red tilapia broodstock was fed a basal isonitrogenous and isocaloric diet (DPP0) or diets supplemented with 10 g (DPP10), 20 g (DPP20), and 40 g (DPP40) of DPP per kilogram of feed for a period of two months.
Key results: A comprehensive boost for reproduction
Blood metabolites and digestive enzymes
Fish fed diets supplemented with 20 g or 40 g of DPP/kg showed significantly higher levels of total protein, albumin, and globulin compared to the control group (P < 0.01). All DPP-supplemented groups exhibited a significant decrease in aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) levels compared to the control group (P < 0.01), with the lowest values observed in the DPP40 group.
Lipase activity significantly improved with DPP inclusion in the diet, while amylase activity remained unaffected (P > 0.05). These findings suggest improved liver function and lipid metabolism.
Reproductive hormones
Fish fed 40 g of DPP/kg diet exhibited significantly higher testosterone levels (P = 0.019). Estradiol (E2) and progesterone (PROG) levels significantly increased with higher dietary DPP levels, with the highest values observed in the DPP40 group (P < 0.001). Dietary supplementation with 20 or 40 g of DPP/kg significantly enhanced serum concentrations of FSH and LH compared to the DPP10 and control groups (P < 0.001).
Overall, dietary inclusion of 40 g of DPP/kg significantly increased testosterone, E2, and PROG levels, while both 20 and 40 g DPP/kg significantly increased FSH and LH levels (P < 0.01).
Organosomatic indices and reproductive rerformance
DPP dietary inclusion did not significantly affect viscerosomatic index (VSI) values (P = 0.221). However, significant improvements were observed in egg diameter (P = 0.007) and hepatosomatic index (HIS) (P < 0.001) in fish fed DPP-supplemented diets compared to the control group.
The mean number and weight of fry per fish were highest in fish fed 40 g of DPP/kg diet, although all DPP-supplemented groups showed higher values than the control group (P < 0.05). Fish fed 20 or 40 g of DPP/kg diets exhibited a significant increase in gonadosomatic index (GSI) compared to fish fed 10 g of DPP/kg and the control group (P < 0.001).
Reproductive gene levels, including CYP1A, FSHR, FOXL2A, ESR1, and ESR2A, significantly increased with higher dietary DPP levels, with the highest values observed in the DPP40 group (P < 0.001). All supplemented groups exhibited higher levels of these genes compared to the control group (P < 0.05).
Gonadal histology
Histological analysis demonstrated that DPP enhanced gonadal maturation in both males and females. In males, improved spermatogenic cell populations and increased testicular tubule diameter were observed, particularly in the DPP20 and DPP40 groups. In females, an increase in the number of growing oocytes and greater vitellogenic yolk deposition were noted in DPP-supplemented groups.
Implications for tilapia aquaculture
By incorporating DPP into red tilapia broodstock diets, fish farmers can potentially enhance reproductive performance, improve offspring quality, and increase overall productivity. This is particularly important in the context of sustainable aquaculture, where optimizing broodstock nutrition can lead to more efficient and environmentally friendly farming practices.
Additionally, DPP is a natural and eco-friendly supplement, making it an attractive alternative to synthetic additives. Its use could help reduce reliance on chemical treatments and antibiotics, which are often associated with negative environmental and health impacts.
Conclusion
Based on the experimental results, researchers suggest that dietary DPP administration (20 or 40 g/kg) significantly promoted gonadal maturation, improved blood biochemistry, and enhanced overall reproductive performance in hybrid red tilapia broodstock. These improvements were accompanied by significant increases in reproduction-related gene expression, better gonadal histology, and elevated reproductive hormone levels. Therefore, this study recommends using DPP (20 or 40 g/kg diet) as a dietary supplement for red tilapia broodstock to maintain reproductive health and contribute to the overall well-being of fish populations in the aquaculture sector.
Future research should explore the long-term effects of DPP supplementation and its potential applications in other fish species. For now, the evidence is clear: DPP is a promising tool for enhancing reproductive performance in red tilapia and supporting the growth of sustainable aquaculture.
Reference (open access)
Alqahtani, N. K., Ghazzawy, H. S., Mathew, R. T., Alkhamis, Y. A., Alngada, R. S., Eissa, M. E., Abdelnour, S. A., Ghanem, S. F., Almutairi, L. A., & Eissa, E. H. (2025). Enhancing reproductive capacity in hybrid Red Tilapia (Oreochromis niloticus × O. Mossambicus) via dietary administration of date palm pollen (Phoenix dactylifera L.). Aquaculture Reports, 41, 102670. https://doi.org/10.1016/j.aqrep.2025.102670
