Dietary Effects of Azanza Garckeana Seed Powder on the Egg Quality of Clarias Gariepinus Broodstocks

The impact of incorporating Azanza garckeana seed meal into the diet on the egg quality of Clarias gariepinus broodstock was examined in a 56-day study. Five isonitrogenous diets with 40% crude protein, were formulated with different levels of Azanza garckeana seed powder: the control diet (AG0) had no inclusion, while AG1, AG2, AG3, and AG4 included 0.5g, 1.0g, 1.5g, and 2.0g of seed powder per 100g of feed, respectively. A total of 45 female Clarias gariepinus broodstock (weighing between 450–470g) were randomly allocated to 15 concrete tanks (2 × 2 × 1.25 m³) at a stocking rate of three fish per tank, with three replicates per treatment. The fish were fed at 3% of their body weight, twice daily (between 8:00–9:00 and 16:00–17:00) throughout the 56-day period. The findings revealed that Azanza garckeana seed powder in the diet had a significant (P≥0.05) effect on the growth performance and egg quality of Clarias gariepinus broodstock, leading to increased fecundity in fish fed AG1 (0.5g) and AG4 (2.0g) diets. Among the treatment groups, broodstock fed 2.0g of Azanza garckeana seed meal (AG4) produced the highest number of eggs (99,292.3). The lowest fertilization rate (95.6%) was recorded in AG2. Interestingly, AG2 also exhibited the highest hatching rate (74.7%), followed by AG1 (66.7%), AG3 (64.5%), AG4 (63%), and the control group AG0 with the lowest (56.9%). After two weeks, hatchling survival was highest in AG1 and AG3 (both 93.3%), followed by AG4 (91.1%), AG0 (88.9%), and AG2 (86.7%). No deformities were observed in hatchlings from any of the treatment groups (AG0–AG4). Histological examination of the ovaries was investigated at the end of the experiment. AG0 (control) displayed normal ovary histology. The smaller, closely packed circular structures represent primordial follicles or early stage developing follicles. In AG1, shows that the ovary of Clarias gariepinus fed AG1 (0.5g/100g Azanza garckeana seed powder) showing larger, more developed follicles that have accumulated more layers of granulosa cells, and an antrum (a fluid-filled cavity) which shows abundant yolks with dispersed nucleolus. Likewise AG2, shows that the ovary of Clarias gariepinus fed AG2 (1.0g/100g Azanza garckeana seed powder) are predominantly larger spaces between the structures, which suggest antral follicles or early stages of the corpus luteum formation post-ovulation with fewer nucleolus and populated yolks. Furthermore, AG3 shows that the ovary of Clarias gariepinus fed AG3 (1.5g/100g Azanza garckeana seed powder) are more compact in appearance with smaller structures which suggest pre-antral follicles or follicles that are transitioning from primary to secondary stages..Lastly, AG4 shows that the ovary of Clarias gariepinus fed AG4 (2.0g/100g Azanza garckeana seed powder) are normal ovary histology with vitellogenic (VS) and perinuclear stages (PS). The study concludes that the addition of Azanza garckeana seed powder to the diet of Clarias gariepinus progressively improves follicular development, from primary stages in the control to advanced vitellogenic and post- ovulatory stages at higher concentrations.