Work

Regulation of serum reproductive hormones, gap junction proteins, and cytokine profiles in laying hens fed varying levels of expanded black soldier fly meal

Year: 2025

Type: article

Abstract: This study examined the impact of expanded black soldier fly (EP-BSF) meal on laying hens' reproductive hormones, gap junction proteins, cytokines, and performance. Over the 12 weeks trail period, 400 Hy-Line brown hens procured at 24 weeks of age underwent a completely randomized design with 5 treatments, 8 replicates, and 10 birds per replicate. The hens received a control diet (CON) or diets with 3 %, 6 %, 9 %, or 12 % EP-BSF. Results demonstrated that lower EP-BSF levels showed a linearly higher (p < 0.05) hen day egg production (HDEP) from 30 to 33 weeks and a linearly higher (p < 0.05) egg mass (EM) in the cumulative weeks comparable to CON. Tendencies towards a linearly higher average egg weight (AEW) was observed when EP-BSF was incorporated at lower levels comparable to CON during 34-37 weeks (p = 0.079), as well as in the cumulative weeks (p = 0.056). Yolk color was quadratically higher (p < 0.024) during 30-33 weeks, with higher tendency (p = 0.050) in the cumulative weeks as the EP-BSF level increases. Albumin weight was linearly higher (p < 0.05) at lower EP-BSF supplementation level comparable to CON at 26-29 weeks and at the cumulative weeks, with linearly higher tendency (p = 0.062) at 34-37 weeks. Eggshell thickness was quadratically increased (p < 0.05) at 30-33 weeks, with a quadratically higher tendency (p = 0.050) during the cumulative weeks as the level of EP-BSF increased. Serum estradiol (E2) levels were linearly increased (p < 0.05) in the lower EP-BSF groups, correlating with increased expression of connexins GJA1 and GJA4 in oviductal tissues and lower tumor necrosis factor-alpha (TNF-α). In conclusion, the incorporation of lower levels of EP-BSF had similar HDEP, AEW, EM, and albumin weight as CON. We attributed this to the increased E2 levels resulting in lower TNF-α, and higher expression of GJA and GJA4 in the chicken oviduct. Our findings also strongly indicate estrogen plays a role in modulating the expression of connexins. These findings suggest that lower EP-BSF in layer diet may serve as an alternative protein source for poultry feed.

Source: Poultry Science

DOI: 10.1016/j.psj.2025.105045