Fermentation characteristics of silage of pearl millet (Pennisetum glaucum (L.) R. Brown) cultivars combined with soybean (Glycine max (L.) Merr.) hull

This study examines the fermentation characteristics of silage of pearl millet (Pennisetum glaucum) cultivars (BRS 1501, ADR 500, ADR 8010) harvested at 65 days of vegetative growth with the inclusion of levels of soybean (Glycine max (L.) Merr.) hulls (0, 3, 6 and 10%). Millet was harvested and ensiled in small silo (mini silo) and kept for 30 days. The laid out in a completely randomized design with a 3 × 4 factorial arrangement with three replicates, where the mini silo was considered an experimental unit. Characteristics such as effluent losses, gas losses, dry matter recovery index and silage composition were evaluated. The highest soybean hull inclusion level (10%) resulted in the lowest gas and effluent losses. Silage dry matter recovery did not differ in response to the inclusion of soybean hulls or between cultivars. Silage pH values ranged from 4.07 to 4.85. Mean buffering capacity ranged from 10.82 (ADR 8010) to 30.19 (ADR 8010) mEq NaOH/100 g DM among treatments. Mean soluble carbohydrate content differed according to the soybean hull inclusion levels and cultivars. Lactic acid content was influenced by the soybean hull inclusion levels, ranging from 5.07% (ADR 8010; at 10% inclusion) to 7.10% (BRS 1501; in control treatment). The inclusion of soybean hulls in the silage of pearl millet cultivars promoted the production of good-quality silage with lower gas and effluent losses. Therefore, the maximum recommended level to include is 10%.