<![CDATA[This study was to evaluate the effect of different levels of Carica seed as a substitute for soybean meal in a total mixed ration in vitro. Parameters observed included physical characteristics of diet, nutrient digestibility (dry matter and organic matter), and rumen fermentation (pH, NH₃, and partial VFA). A completely randomized design with four treatments and five replications was applied. The treatments were T1 (85%complete feed+15% soybean meal + 0% Carica seed), T2 (85% complete feed + 10% soybean meal, 5% Carica seed), T3 (85%complete feed + 5% soybean meal + 10% Carica seed), and T4 (85%complete feed+ 0% soybean meal+ 15% Carica seed). This study showed that bulk density of T4 was highest among treatments and T1 was the lowest one (p<0.05). Moisture content and hardness in this study was similar among treatments (p>0.05). An average of moisture and hardness was 6.8% and 3.6 kgforce, respectively. The study showed that dry matter digestibility (DMD) of T1 (65.32%) was similar to T2 (64.00%) and higher than that of T3 (57.40%) and T4 (53.90%). Organic matter digestibility (OMD) of T1 (77.41%) and T2 (76.74%) was also similar and higher than that of T3 (69.85%) and T4 (66.79%). Rumen fluid profiles also were not significantly different (p>0.05). An average of pH, NH₃, acetic acid, propionic acid, and A/P ratio was 6.58, 5.5 mM, 10.8 mM and 1.5, respectively. However, butyric acid of T3 and T4 was similar and lower than that of T2 and T1 (p<0.05). Butyric acid of T1 was the highest among treatments (p<0.05). In conclusion, the use of Carica seed as the substitution of soybean meal decreased the bulk density without altering water content and hardness. Carica seed also reduced the digestibility of feed. The substitution of Carica seed did not alter rumen fluid profiles but butyric acid. Carica seed could be used as substitution for soybean meal up to 15% without altering nutrient utilization.]]>
