Comparison of the effects of alfalfa meal and sorghum distillery residue supplementation on the methane emissions in black-feathered Taiwan native chicken.

ABSTRACT

The issue of global warming, primarily fueled by anthropogenic greenhouse gas emissions, necessitates effective strategies to address methane (CH4) emissions from both ruminants and nonruminants. Drawing inspiration from successful approaches employed in ruminants, this study evaluates the impact of supplementing the diets of Taiwan's native black-feathered chickens with alfalfa meal and sorghum distillery residues (SDRs) on CH4 emissions. Using a respiration chamber the results reveal a significant reduction in CH4 emissions when incorporating either 30% alfalfa meal or 30% SDRs into the chicken diet, demonstrating a 59% and 49% decrease, respectively, compared to the control group (P < 0.05). Considering that alfalfa meal contains saponins and SDRs contain tannins, the study delves into the mechanism through which these components mitigate CH4 production in chickens. Incorporating saponins or tannins shows that groups supplemented with these components exhibit significantly lower CH4 emissions compared to the control group (P < 0.05), with a consistent linear decrease as the concentration of the feed additive increases. Further in vitro analysis of chicken cecal contents indicates a proportional reduction in CH4 production with increasing levels of added saponins or tannins (P < 0.05). These findings suggest that the CH4-reducing effects of alfalfa meal and SDRs can be attributed to their saponins and tannin content. However, caution is warranted as excessive alfalfa meal supplementation may adversely impact poultry growth. Consequently, sorghum distillery residue emerges as a more suitable feed ingredient for mitigating CH4 emissions in Taiwan's native black-feathered chickens compared to alfalfa. Additionally, substituting SDRs for conventional commercial chicken feed not only reduces CH4 emissions but also enhances the utilization of byproducts.

In this study, researchers focused on addressing the crucial issue of global warming by tackling methane (CH4) emissions from chickens, an important source of greenhouse gases. We investigated the impact of adding alfalfa meal and sorghum distillery residues (SDRs) to the diets of Taiwan's native black-feathered chickens. The results showed a reduction in CH4 emissions when incorporating either 30% alfalfa meal or 30% SDRs into the chicken diet. This led to a 59% and 49% decrease, respectively, compared to the control group. The study explored the mechanism behind this reduction, pointing to the presence of saponins in alfalfa meal and tannins in SDRs as key components influencing CH4 production. However, the study also highlighted a potential concern regarding excessive alfalfa meal supplementation, which could negatively impact poultry growth. On the other hand, SDRs were found to have no detrimental effects, making them a more suitable feed ingredient for mitigating CH4 emissions in Taiwan's native black-feathered chickens compared to alfalfa. Moreover, substituting SDRs for conventional commercial chicken feed not only reduces CH4 emissions but also contributes to the enhanced utilization of byproducts, promoting a more sustainable approach to poultry farming.