Physical parameters of complete feed blocks based on wheat straw and sugarcane bagasse

Wheat straw (WS) in complete feed (CF₁, Roughage: Concentrate 60:40) was replaced with 40% (w/w) dried sugarcane bagasse (SB) (CF₂) and mustard cake of CF₂ was replaced with formaldehyde treated mustard cake in complete feed CF₃. The complete feeds in mash form, were densified in to blocks of 14 kg each (53x42x13 cm.) by the application of pressure of 204 ton/m² (3000 psi) for a dwell time of 30 sec. Modulus of uniformity and modulus of fineness of sugarcane bagasse (SB) was 2: 4: 4 and 3.78, respectively. Bulk density (kg/m³) of SB (81.27) was higher (P<0.05) than that of WS (68.32). Bulk density of complete feed blocks CF₂ and CF₃ was higher (P<0.01) than that of CF₁. However, variation between CF₂ and CF₃ was not significant showing that incorporation of formaldehyde treated mustard cake did not influence bulk density of complete feed. The bulk density of complete feeds increased 4.5 folds following their densification in block form. Post compression expansion (PCE) of feed blocks CF₁, (WS based) after 30 days of storage at ambient conditions was higher (P<0.05) than those based on SB (CF₂ and CF₃). Durability of CF₁ blocks was lower (P<0.01) than CF₂ and CF₃ blocks. Equilibrium moisture content (EMC) of blocks increased with the increase in RH and decreased on increasing the temperature. The cost of 14 kg CF₁, CF₂ and CF₃ block excluding the cost of processing, packing and transportation was Rs. 53.90, 49.56 and 50.82, respectively. It was concluded that 40% replacement of WS with dried SB in feed blocks improved their physical attributes such as bulk density, PCE, and durability besides decreasing the feed cost, however, replacement of mustard cake with that treated with formaldehyde in feed block did not affect its physical attributes.