Biokonversi serat sawit dengan Aspergillus niger Pensintesa Cr-Organik sebagai komponen ransum komplit domba

Abstract

Palm press fiber (PPF) as cattle feed has not yet optimally utilized; one constraint is its low content of crude protein (3.93%) and its high content of crude fiber (48.96%), which can inhibit growth and decrease the feed digestibility. To overcome such condition, palm press fiber can be processed to improve its nutrition through physical, chemical and biological treatments. The objectives of this research were to improve the utility of PPF as animal feed and examine the nutritional level of PPF treated with NaOH and then fermented with A. niger as a synthesizer of organic Cr to replace a component of sheep feed. The study consisted of three stages. The first stage was the immersion of PPF with NaOH. In the second stage, the best result of the first stage was used for the fermentation of PPF with A.niger as the synthesizer of organic Cr to produce fermented PPF . The second stage was also to produce the right level of inoculums of A. niger and CrCl3 to obtain PPF with the highest digestibility and content of nutrients as well as Cr-yeast. The first experiment with factor A = Level of NaOH (A1=2,5%, A2=5%, A3=7,5%) and factor B = immersion length in NaOH (B1=6 hours B2=12 hours, B3 = 24 hours). The second experiment consisted of factor A, the yeast levels of A. niger i.e (1) 5.0% Dry Matter (DM), (2) 7.5% DM, (3) 10% DM, of substrate and in factor B the levels of CrCl3 added to the substrate were (1) 2 mg/kg substrate, (2) 4 mg/kg substrate, (3) 6 mg/kg substrate, with the addition of tryptophan of 600 ppm for each treatment. The parameters observed in the experiments were protein, crude fiber organic Cr, ADF and NDF. The second stage of the research was an in-vitro experiment to assess the digestibility of fermented PPF in the rumen with the observed variables of total VFA, NH3, DM digestibility and OM digestibility. The target of this experiment was to produce fermented PPF with the best contents of nutrients and organic Cr as well as the highest digestibility. The third stage was an in-vivo experiment in sheep to produce a complete formula of feed made of fermented palm press fiber which could promote an optimum growth of sheep. The best result of fermented PPF in stage two was used to formulate 4 types of complete feed with TDN 64% and Protein 12.5%. The levels of fermented PPF in the feed were: A = 0% PPF + 60% native grass (NG) + 40% concentrate, B = 15% PPF+ 45% NG + 40% concentrate, C= 30% PPF + 30% NG + 40% concentrate, D= 45% PPF + 15% NG + 40% concentrate. The research results showed that the best level of NaOH and immersion periode to increase the nutritional content of PPF were 2.5% NaOH and immersion for 24 hours, A. niger could synthesize organic Cr by using CrCl3 and tryptophan as the precursors, the treatment with 10% inoculum of A. niger and 6 mg CrCl3/kg could produce the highest digestibility of dry and organic matter. Fermented PPF could be used as substitute for 45% native grass without reducing the quality of sheep meat In contrast, the use of 45% fermented PPF in the ration could reduce fat and cholesterol content and increase organic Cr in meat.

Sebagai pakan ternak, serat sawit yang ada belum dapat dimanfaatkan secara maksimal, salah satu kendala serat sawit adalah rendahnya protein kasar yaitu 3.5% dan tingginya kandungan serat kasar yaitu 48% yang dapat menghambat pertumbuhan dan menurunkan tingkat kecernaan pakan. Menyadari kondisi tersebut untuk menanggulanginya dari segi nutrisi adalah dengan cara pengolahan secara fisik, kimia dan mikrobiologi. Biokonversi menggunakan fungi pensintesa kromium organik (Cr-yeast) sangat tepat diterapkan untuk pengolahan serat sawit yang telah diperlakukan alkali dengan NaOH, karena selain akan meningkatkan nilai nutrisi, juga memperkaya kandungan mineral Cr yang dibutuhkan untuk memacu pertumbuhan dan meningkatkan kualitas daging. Tujuan dari penelitian ini adalah untuk meningkatkan daya guna serat sawit sebagai pakan ternak. Mengkaji kemampuan nutrisi serat sawit yang diperlakukan dengan NaOH kemudian difermentasi dengan A. niger pensintesa Cr-organik dalam mengganti sebagian ransum ternak domba. Penelitian terdiri dari tiga tahap. Tahap pertama, pemeraman serat sawit dengan NaOH. Tahap kedua, hasil terbaik dari tahap pertama, fermentasi serat sawit dengan A.niger pensintesa Cr-organik pembuatan serat sawit fermentasi. Penelitian ini untuk mendapatkan level inokulum A. niger, level CrCl3 yang tepat untuk menghasilkan serat sawit dengan kecernaan dan kandungan nutrisi serta Cr-yeast tertinggi. Penelitian ini meliputi pembiakan kapang, pembuatan inokulum, penyediaan media fermentasi, fermentasi serat sawit dengan A. niger. Rangkaian pengerjaan fermentasi serat sawit dilakukan setelah dimodifikasi sesuai dengan keperluan. Penelitian tahap I, dilakukan dengan rancangan acak lengkap (RAL) pola faktorial dengan 2 faktor (3x3) dan 2 ulangan (Steel & Torrie 1993). Faktor perlakuan A adalah level konsentrasi NaOH yaitu 2,5%,5%, dan 7,5% dan faktor perlakuan B adalah lama pemeraman serat sawit dalam NaOH yaitu 6 jam, 12 jam, dan 24 jam. Peubah yang diamati dalam penelitian ini adalah: (1) kandungan nutrisi meliputi bahan kering, protein kasar. (2) Kandungan fraksi serat NDF, ADF, selulosa, hemiselulosa, dan lignin ditentukan dengan analisis Van Soest; (3) struktur dinding sel (scanning electron microscope).