Silver nanoparticles (Ag-NPs) are emerging as natural antimicrobial growth promoters in poultry, known for enhancing gut health, immunity, and productivity. This study assessed the effects of Ag-NPs and silver nitrate (AgNO₃) on sexual behavior, productivity, and silver bioaccumulation in the reproductive tissues of Japanese quails (Coturnix japonica). A total of 600 quails (8 weeks old) were randomly assigned to five groups (120 birds/group), each with six replicates (sex ratio 5 male: 15 females). Group 1 (control) received a basal diet, while Groups 2 and 3 were supplemented with Ag-NPs at 10 mg/kg and 20 mg/kg, respectively. Groups 4 and 5 received AgNO₃ at the same doses for eight weeks. Quails receiving 10 mg/kg Ag-NPs showed significantly improved male mating behavior, increased egg weight and mass, and enhanced egg quality, resulting in the highest fertility and hatchability performance. Silver accumulation in ovaries and testes increased dose-dependently, with the highest deposition observed in the 20 mg/kg Ag-NPs group. Correlation and regression analyses revealed weak and statistically non-significant relationships between ovarian silver levels and fertility and hatchability outcomes. These findings suggested that supplementation with 10 mg/kg Ag-NPs was a safe and effective feed additive for improving both productive and reproductive performance in Japanese quails.

Comparative assessment of natural and synthetic reproductive inhibitors in Oreochromis niloticus

Micro-plastic pollution is a significant global concern that has far-reaching consequences for the environment and human activities, particularly aquatic ecosystems. Microplastics have become pervasive in all marine environments, from the surface waters to the deep ocean, even in remote regions. Their small size, lightweight nature and colorful appearance make them highly mobile and easily dispersed by wind and water currents. They enter the ocean through rivers, runoff, and atmospheric deposition. They are easily ingested by various species, from zooplankton to large fish and marine mammals. Consequently, the production of these compound pollutants may also find its way into the food chains of aquatic life and, after an extended period of enrichment, into the human body. Furthermore, cumulative harmful effects of compound pollution on human health and the natural environment are a result. The accumulation of microplastics in their organs can disrupt physiological functions, cause behavioral changes, and impair growth and reproduction. Addressing this problem requires global cooperation and a multifaceted approach to reduce plastic production and better manage plastic waste.

The present study was designed to evaluate the effect of supplementation with papaya seeds (PSM), fish testes powder (FTP), and 17α-methyltestosterone (MT) on the reproductive parameters, growth performance, digestive enzymes, and histology of Cyprinus carpio. In the present study, fries (2–3 days old) were acclimatized for 2 days and then equally distributed into one control and six treatment groups and fed with one control and six experimental diets for 30 days, followed by a control diet for 60 days in each group with triplicates. These diets included control (T0), different levels of 17α-methyltestosterone (T1: 60 mg/kg; T2: 70 mg/kg), papaya seed powder (T3: 6 g/kg; T4: 7 g/kg), and fish (tilapia) testes powder (T5: 70%; T6: 80%). The treatment groups receiving papaya seed meal (PSM) showed significant improvements in growth performance, with a significant increase in final body weight. The best zootechnical performances (PER, SGR, and CF) were observed in fish fed with papaya seed compared to the control group. Reproductive analysis showed significant variations between treatment groups, with a large number of female C. carpio observed in the control group. Fish treated with T4 increased the sex percentage in favor of male fish by achieving 90% male phenotype followed by T6 with 88% male. Diets based on papaya seeds and fish testes powder significantly reduced the reproductive performance by reducing GSI, which affected the gonadal histology. The results revealed a visible effect of 17 α-MT and PSM feeding on the gonad structure. There were significant elevations in protease enzyme activity in T6 compared to the control (p < 0.05), and the highest amylase activity was observed in T3. Natural resources are not only more cost-effective but also environmentally friendly and readily available; they are a superior choice over synthetic alternatives for controlling the prolific breeding of C. carpio.