In vitro fermentation and chemical constituents of urea-molasses feed - blocks made with different binders for ruminants.

Résumé

This study was carried out to assess the chemical contents, in vitro break down, volatile fatty acids, NH3¬-N and methane concentration of urea- molasses feed - block (UMFB) using different binders. Four feed - blocks were formulated as: UMFB A (Cement only), UMFB B (cement + clay), UMFB C (cement + cassava starch), and UMFB D (cassava starch + clay). The feed - blocks were incubated in vitro for 48 hours to assess gas production and other in vitro- ecology parameters. Results of chemical analysis revealed that UMFB C (21.70%), and B (21.65%) had highest (p< 0.05) crude protein content while UMFB D (18.62%) had lowest value. Intermediate crude protein content was recorded for UMFB A (19.58%). However, highest (p<0.05) values of ADF (16.8%) and ADL (15.5%) were recorded for UMFB D. Similar value of ADF (16.70%) and ADL (15.3%) were recorded also for UMFB B. The NDF value of feed - block A (34.6%) was highest (p<0.05) while lowest value of NDF was recorded for UMFB D (32.1%). Production of volatile fatty acids indicated that propionic acid (30.5%), oleic acid (11.3%,) and lactic acid (36.5%) were highest (p<0.05) for UMFB D. Concentration of NH3-N was highest in UMFB B while significant difference (p>0.05) was not observed in the pH and methane values for various UMFB. Highest in vitro digestibility of organic matter was observed in UMFB D. The study showed that the various feed - blocks could serve as a sustainable supplement during dry season and period of scarcity for the ruminants.