STUDI TENTANG PENAMBAHAN PROBIOTIK TERHADAP PENAMPILAN AYAM KEDU YANG MENDAPAT RANSUM BERBEDA LEVEL PROTEIN DAN SERAT KASAR

Abstract

Probiotic called starbio is a microbial colony which is able to decompose the dietary tissues structure within the digestive tract, and produce active enzymes to hydrolize protein into amino acids. Therefore, this substance is able to accelerate reactions in the decomposition of polypeptide bound into peptides and free amino acids. The present study was aimed to evaluate the effect of feeding probiotic starbio as an additive substance on performance of growing Kedu chicken. One hundred forty four (144) birds of male (initial body weight 416.35 ± 19.30 g) and female (initial body weight 353.83 ± 19.96 g) Kedu chickens were used, respectively, with a separate observation between sex. Experimental diets, that were composed iso-energy, were fed ad libitum from 1 month old to 3.5 months of age. The experiment was arranged in a factorial scheme of 2 x 2 x 3 within a completely randomized design (CRD) with 4 replication (3 birds each) for respective sex. First factor (A) 2 levels of protein, namely 15 % (Ai) and 13 % (A2), second factor (B), 2 levels of crude fiber, namely 10 % (B1) and 12 % (82), and third factor (C), 3 levels of starbio, namely 0 % (C1), 0.25 % (C2) and 0.50 % (C3). Feed consumption, protease enzyme activity protein digestibility, Nitrogen retention and body weight gain were the parameters measured in the present study. The results indicated that feeding 0.25 % as well as 0.50 % of probiotic-starbio decreased feed consumption in male chicken (P<0.05). An interaction among protein (A), crude fiber (B) and probiotic-starbio (C) was obvious on protease enzyme activity at pH level of digestive tract (pH = 6.0). The higest enzyme activity was observed in male chicken and it was significant due to the combined effect of 15 % protein (AI), 10 % crude fiber (B1) and 0.25 % starbio (CI), but that found in female chicken was produced by the combined effect of 15 % protein (Al), 12 % crude fiber (B2) and 0 % starbio (CI). Control diet (without starbio) produced the highest protein digestibility and Nitrogen retention both in male and female chickens. The interaction effect of B factor (crude fiber) and C factor (starbio) was significant on body weight gain in male (P<0.05) with the highest value (688.91 g) was achieved by the combination of B1 (10 % crude fiber) and CI (without starbio). Diet containing highes level of protein (15 %) seems to require supplementation of 0.25 % starbio, on the other hand, diet with lower protein level (12 %) is more suitable when 0.50 starbio is added in order to achieve better respons. Probiotik dengan nama starbio merupakan koloni mikroba yang dapat membantu penguraian struktur jaringan pakan, didalam saluran pencemaan dapat menghasilkan enzim yang aktif memecah protein menjadi asam amino. Oleh sebab itu substansi ini dapat mempercepat reaksi dalam penguraian ikatan polipeptida menjadi peptida dan menghasilkan asam amino bebas. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian probiotik starbio sebagai zat additif terhadap penampilan ayam Kedu periode pertumbuhan. Penelitian menggunakan ayam Kedu jantan dengan bobot badan awal 416,35 ± 19,30 g dan ayam Kedu betina dengan bobot awal 353,83 + 19,96 g masing-masing sebanyak 144 ekor, dengan pengamatan yang terpisah. Ransum perlakuan mulai diberi kan pada saat ayam berumur 1 bulan sampai umur 3,5 bulan. Ransum perlakuan disusun berdasarkan iso energi. Penelitian disusun dalam rancangan acak lengkap (RAI.) berpo¬la faktorial 2 x 2 x 3 dengan 4 ulangan (tiap ulangan terdiri dari 3 ekor) untuk masing¬masing jenis kelamin. Perlakuan yang diterapkan merupakan perbedaan level protein (faktor A) yaitu 15% (A1) dan 13% (A2); level serat kasar (fak for B) yaitu 10% (B1) dan 12% (B2) serta level starbio (faktor C) yaitu 0% (CI); 0,25% (C2) dan 0,50% (C3). Parameter yang diamati meliputi konsumsi ransum, aktivitas spesifik enzim protease, kecemaan protein, retensi nitrogen dan pertambahan bobot badan. Hasil penelitian menunjukkan bahwa pemberian probiotik starbio sebesar 0,25 % dan 0,50 % menurunkan konsumsi ransum pada ayam jantan (P<0,05). Penga¬ruh interaksi antara protein (A), serat kasar (B) dan probiotik starbio (C) tampak terha¬dap aktivitas enzim protease pada kondisi pH sal uran pencemaan (p1I = 6,0). Aktivitas enzim paling tinggi pada ayam jantan secara nyata (Pc 0,05) terjadi pada kombinasi fak for protein 15 % (A1), serat kasar 10 % (B1) dan probiotik starbio 0,25 % (CI), tetapi pa da ayam betina aktivitas enzim tertinggi dihasilkan olch kombinasi faktor protein 15 % (Al), serat kasar 12 % (B2) dan tanpa probiotik starbio (CI). Kecernaan protein dan re tensi N tertinggi dicapai oleh perlakuan kontrol (tanpa starbio) baik pada jantan maupun betina. Interaksi antara faktor B (serat kasar) dan faktor C (starbio) terhadap pertambah¬an bobot badan tampak nyata pada jantan (P<0,05) tetapi tidak nyata pada betina de ngan nilai tertinggi (688,91 g) dicapai oleh kombinasi B1 (SK 10 %) dan Ci(tanpa star¬bio). Ransum dengan kadar protein yang lebih tinggi (15 %) memerlukan penambah¬an probiotik starbio sebesar 0,25 % dan ransum dengan kadar protein yang lebih rendah (13 %) memerlukan penambahan probiotik starbio sebanyak 0,50 % untuk memberikan