Legume–grass intercropping systems are a sustainable option to improve nutritional quality of animal feed and decrease livestock greenhouse gas emissions. Thus, the present study evaluated yield, chemical composition and in vitro gas production of silages produced with intercropped palisade grass (Urochloa brizantha.(A.Rich.) R.D.Webster), pigeon pea (Cajanus cajan cv. Super N) and corn (Zea mays. L.). Forage was harvested and placed inside micro-silos, which were opened after 100 days and samples were collected for chemical composition and in vitro gas production analyses. Intercropped silage had higher crude protein, acid detergent fiber, and lignin content than corn silage. Moreover, intercropped silage decreased total gas and methane production. Therefore, intercropped silage showed potential to increase conserved feed nutritional quality and reduce methane emissions in livestock production systems.

The feasibility of unconventional feed for ruminants must be analyzed for appropriate use as sources of energy or protein that contribute to a sustainable production system addressing concerns about climate change, greenhouse gas emissions, and food security. The objective of this study was to evaluate the nutritive value of by-products including bean residue (BR), bean straw (BS), cassava bagasse (CB), corn straw (CS), orange bagasse (OB), peanut shell (PS), sugarcane bagasse (SB), soybean hull (SH), and sugarcane straw (SS). Chemical composition, in vitro degradability, and fermentative parameters were analyzed and subjected to multivariate and principal component analyses. Crude protein content was highly variable among by-products with BR and SH presenting the highest values (p < 0.001). These values did not differ between BR and SH, while the lowest values were observed in OB, PS, SB, SS, CS, and CB. Neutral detergent fiber content was higher in SB, PS, CS, and SS (p < 0.001), while greater in vitro degradability was found for CB, BR, OB, BS, and SH (p < 0.001). However, the in vitro gas production (p < 0.001) and total short-chain fatty acid concentration (p < 0.001) were higher in CB, BR, BS, and OB. Multivariate cluster analysis showed three distinct groups with the most degradable in group 1 followed by group 2. These results demonstrate that the by-products used in this study did not impair in vitro fermentation, and thus have the potential to be used in the diets of ruminants and to improve the sustainability of the livestock production sector.

Tithonia diversifolia (Hemsl.) A. Gray has significant potential as a forage source in silvopastoral systems, particularly in tropical conditions. However, its intensity and frequency management differ from those commonly applied to grasses. This study aims to evaluate T. diversifolia under two harvest intensities (30 and 40 cm stubble height) and four harvest frequencies (21, 28, 35 and 42 days), aligning with Brazil's traditional tropical grass management practices. Biomass production and nutritive value of forage, as well as in vitro rumen fermentation parameters, were assessed. We observed that the tested harvest intensities have a limited impact on the biomass production and nutritional value of T. diversifolia. Despite the linear increase in biomass production, lower harvest frequencies (i.e., longer regrowth period) significantly affect nutritional value, impacting the products of ruminal fermentation, as indicated by the in vitro assay. The methane production per gram of degraded organic matter (OM) and the OM allocated for microbial biomass production are affected by the harvest frequencies. Additionally, we observed that rainfall and canopy height have a stronger correlation with biomass production than harvest frequencies controlled by days. We conclude that T. diversifolia is minimally affected by harvest intensities and, for Brazilian edaphoclimatic conditions, it can be harvested with higher frequencies than those suggested for other regions.