Feed shortages are an acute problem for livestock farming in developing countries. Currently, ruminants are fed only with rice straw, which is of very poor quality. The nutritional value of rice straw can be improved by supplementing it with aquatic plants, with water hyacinth (Eichhornia crassipes) being the most prominent. Water hyacinth contains as much protein and minerals as many conventional feed sources. This plant has high resilience with a high production rate and requires no production costs. However, water hyacinth has a very high water content, resulting in a low nutrient density. This issue can be overcome by removing some moisture through partial sun drying, allowing it to be used as livestock feed. Therefore, this book offers a new technology to enhance the quality of low-grade roughage-based diets and to alleviate the chronic feed shortages faced by poor farmers who can raise large ruminants only due to feed costs. The use of water hyacinth in cattle nutrition alongside rice straw would help address the feed crisis, improve animal health, and gradually increase farmers' incomes. This process will enhance animal protein (meat and milk) production and mitigate the protein deficiency needs of humans.