Comparative Nutritional Composition of Azolla pinnata at Different Harvest Stages for Low-Cost Animal Feed Development

Abstract

This study aimed to evaluate the yield and nutritional composition of Azolla pinnata harvested at different growth stages (7, 14, and 21 days) to determine the optimal harvest age for use as a cost-effective livestock feed. A completely randomized design (CRD) with three treatments and three replications was applied. Fresh weight, dry weight, and dry matter content were measured, and chemical composition—including crude protein, ether extract, ash, organic matter, neutral detergent fiber (NDF), and acid detergent fiber (ADF)—was analyzed using standard AOAC International (2016); Van Soest et al. (1991) methods. Results showed no significant differences in yield parametersacross treatments (p > 0.05); however, significant changes in nutritional quality were observed (p < 0.05). Crude protein decreased with increasing harvest age (19.78% at 7 days to 14.90% at 21 days), while ADF increased significantly (10.93 % to 54.85 %). Ash content declined, whereas organic matter increased over time. The highest lipid content was recorded at 14 days (1.66 %). This study confirms that Azolla pinnata harvested at 7–14 days provides a superior nutritional profile with higher protein and lower fiber content compared to 21-day-old plants, without compromising biomass yield. This suggests a more precise harvest window for optimizing both feed quality and production efficiency. These findings support the use of early-harvested azolla as a viable alternative protein-rich feed resource for livestock, particularly in smallholder farming systems seeking low-cost, sustainable solutions.