Transforming forage nutrition: Advances in silage additives for enhanced preservation and feed quality

Global demand for livestock products increases the need for high-quality fodder. However, urbanization resulted in the depletion of agricultural lands expanding the demand for food, feed and fodder. To overcome this issue, the available fodder and agricultural wastes are preserved anaerobically to feed animals. This efficient process of preserving the fodder anaerobically throughout the year is known as ensiling and the preserved fodder is known as silage. To improve the quality and longevity of silage, various additives such as microbial inoculants (bacterial inoculants, yeast), enzymes, chemical additives (organic and mineral acids), nutrients (urea, ammonia, sodium chloride, sodium di acetate) and fermentation accelerators (molasses, starchy substance, grains) are added. Addition of these additives reduces pH to below 4.2, proteolysis up to 40 %, ammonia volatilization, population of yeasts, molds and enhances fermentation, improves the aerobic stability by 2-5 days, optimizes nutrient retention and quality of silage. By supporting better livestock nutrition, silage additives increase 5 to 20% milk production, lactation period and promote beneficial microbial populations in the rumen of cattle. This review describes the usage and effectiveness of various additives that are used to enhance the silage quality in terms of storage and nutritional content.