Abstract
To effectively utilize crop by-product resources for ruminant feed in semi-arid West Africa, we studied the chemical composition, characteristics concerned with fermentative quality, and microbial population of ensiled pearl millet stover (PMS) and sorghum stover (SS) in Mozambique. After panicle harvest, the PMS and SS were exposed in the field for 7, 21, 35, 49, 63, 77, 91, and 120 days under natural weather conditions. The fresh stover silages were prepared and stored for 120 days. With increased exposure time, the dry matter, neutral detergent fiber, acid detergent lignin, and neutral detergent insoluble nitrogen contents increased, whereas the crude protein, ether extract, gross energy, digestible energy, metabolizable energy, and true protein contents decreased. After 120 days of field exposure, aerobic bacteria dominated both stovers, and lactic acid bacteria (LAB) decreased to below detectable levels. After 120 days of ensiling, LAB dominated the silage of both crops, while the harmful microorganisms as aerobic bacteria, coliform bacteria, yeast, and mold were reduced or below detectable levels. Both silages did not produce more lactic acid to reduce the pH value, but they preserved nutrients well during ensiling. Therefore, PMS and SS can be prepared as silage for ruminant feed in semi-arid West Africa.