Effects of Different Inclusion Rates of Pre-Treated Rubber Seed Meal (RSM) on Physicochemical Properties of Juvenile Macrobrachium rosenbergii Feed

Abstract

The present study investigated the potential of rubber seed as an alternative ingredient partial inclusion with improved nutritional value and inexpensive freshwater prawn feed. Rubber seeds are proven to have a nutritional composition such as protein suitable in animal feed. In this study, Rubber Seed Meals (RSM) were formulated using different inclusion rates of 10%, 20%, 30% and 40% Sodium Bicarbonate Treated Rubber seed (SBRS) as a partial replacement to fish meal in prawn diets, while feed without SBRS as control. The study’s objectives were to evaluate the chemical composition and sensory acceptability of the newly formulated RSM through proximate analysis, physical properties analysis and Textural Profile Analysis (TPA). Each of the analyses was performed in triplicates. The preliminary proximate analysis revealed that raw rubber seed powder contained a higher amount of crude protein (19.63%), crude fat (40.00%), crude fibre (7.20%) and metabolisable energy (4961 Kcal/kg) as compared to the SBRS powder. Among all treatments, a diet with 40% inclusion of SBRS showed the highest value of crude fat of 40.80% while with 0% SBRS has the lowest value of 27.22%. In conclusion, RSM with 20% inclusion of SBRS was found to be the most suitable diet that satisfies the nutritional needs of juvenile M. rosenbergii; due to its acceptable content of crude protein (32.70%), crude fat (31.88%), crude fibre (5.33%) and ash content (4.50%). In addition, diet with 20% inclusion of SBRS as the potential alternative prawn feed by having suitable physical properties with bulk density (0.57 g/mL) and sinking velocity (0.09 s/cm). In addition, values for hardness of the pellet were 1073 g and for cohesiveness and springiness were 1.15 and 8.46, respectively.