The rapid proliferation of water lettuce, Pistia stratiotes, poses significant ecological challenges. This study investigates the use of Pistia stratiotes as a substrate for producing black soldier fly larvae. The experiment used 40 g of black soldier fly larvae (BSFL) pupae for all five substrates (T0, T25, T50, T75, and T100). Each treatment had three replicates. The physicochemical parameters, such as the temperature and pH, ranged from 27.30 °C to 27.40 °C and from 7.03 to 7.60, respectively. The survival rates ranged from 90.13% to 94.73%. The biochemical parameters showed significant differences, including dry matter, organic matter, ash, crude protein, crude lipid, crude fiber, carbohydrate, and energy (p < 0.05). Regarding the larvae’s growth and substrate use, the BSFL production varied depending on the rearing substrate. The highest growth was observed in substrates without water lettuce leaf (WLL) (T0), followed by those in treatment at 25% (T25) and 50% (T50) inclusion of WLL and then the substrate made solely of WLL (T100). The substrates degradation rate in this study varied significantly, ranging from 46.40% to 67.38%. The physicochemical characteristics of the substrates are associated with the growth performance of the BSFL, and the inclusion of WLL influenced the nutritional composition of the larvae.

Poultry eggs are considered an affordable and economical source of protein and energy available even in rural areas. The goal of this study was to assess and compare the effects of four different egg yolks on the growth performance and economic profitability of Clarias gariepinus larvae after vitelline resorption (3 days post hatch (DPH). Five experimental diets were tested. The control treatment (T0) consisted of Artemia cysts (zooplankton), while the other treatments included chicken egg yolk (T1), quail egg yolk (T2), guinea fowl egg yolk (T3), and turkey egg yolk (T4). The experimental design was a completely randomized design of 5 treatments with 3 replicates. The experiment lasted for 12 days. The larvae were fed five times a day. Interval sampling was conducted every four days. Growth parameters showed that treatment T0 (Artemia-fed larvae) achieved the highest biomass increase, rising significantly from 1006.66 ± 3.33 mg to 3533.33 ± 145.29 mg over the 12-day experimental period. Treatments T2 (quail egg yolk) and T4 (turkey egg yolk) demonstrated intermediate growth performance, while T1 (chicken egg yolk) and T3 (guinea fowl egg yolk) exhibited the lowest biomass gains, ranging from 1006.66 ± 6.66 to 1433.33 ± 33.33 mg and 1010.00 ± 2.88 to 1866.66 ± 66.66 mg, respectively. Survival rates showed no significant differences among T0, T2, and T4 (P > 0.05). Although T0 exhibited superior growth performance, it incurred a significantly higher economic conversion ratio, indicating increased feed cost per unit of biomass produced (P < 0.05). These findings suggest that while Artemia supplementation promotes rapid growth, its higher cost may affect overall economic efficiency compared to alternative egg yolk-based diets. Given the results on growth and survival performances as well as economic profitability, freeze-dried quail egg yolk and turkey egg yolk can be recommended for better optimization of C. gariepinus larval breeding mainly in rural conditions.

The Special Wildlife Reserve of Gueumbeul (RSFG) consists of a water reservoir (the basin) frequented by a diversity of fish and migratory birds. The most represented in terms of abundance is the species Sarotherodon melanotheron. The objective of this study was to determine the relations weight-length and to characterize the condition factor of S. melanotheron, in the basin of Gueumbeul. A total of 628 fish were sampled including 364 males, 178 females and 86 immature individuals from March 2019 to February 2020. The total length (TL) of S. melanotheron specimens sampled in the Gueumbeul reserve ranged from 6.1 cm to 17.6 cm with an average of 11.08 ± 1.82 cm and the weight (W) from 4.8 g to 103 g with an average of 27.25 ± 12.09 g. The results of the weight-length analyses gave values of 2.69 and 2.77 for the regression coefficient (b) for males and females respectively, and 2.72 and 2.76 for the dry and wet seasons. This reflects negative allometric growth in both sexes (male and female) and by season (dry and wet season). No statistically significant difference was noted for dry and wet season b values for S. melanotheron in the Gueumbeul basin, unlike condition factors between males and females and between dry and wet season where significant differences in K values were noted.

The velvet bean (Mucuna pruriens) is an important source of protein in animal feed. This study investigates the potential substitution of soybean (Glycine