Kajian dan validasi faktor-faktor yang mempengaruhi efikasi penggunaan feses kerbau sebagai pengganti cairan rumen dalam penetapan kecernaan in vitro pakan di daerah tropik

SUDIRMAN, Promotor Prof.Dr.Ir. Ristianto Utomo, SU

2007 | Disertasi | S3 Ilmu Pertanian (Ilmu Peternakan)

Tujuan umum disertasi ini adalah untuk mengkaji dan memvalidasi efikasi penggunaan feses sebagai pengganti cairan rumen sebagai sumber mikrobia dalam penetapan kecernaan in vitro pakan di daerah tropik. Tujuan khusus adalah penentuan: jenis pakan dan spesies ternak, level feses ideal untuk inokulum, waktu dan lokasi koleksi serta lama simpan feses, jenis pengencer, dan rasio inokulum feses/buffer. Sapi peranakan ongole dan kerbau lumpur betina dewasa berfistula rumen (masing-masing dua ekor) diberikan secara berseri tiga jenis ransum: 40 % jerami padi + 60 % konsentrat, 55 % hijauan jagung + 45 % konsentrat, dan 70 % rumput gajah + 30 % konsentrat. Penelitian selanjutnya menggunakan kerbau lumpur dengan ransum rumput gajah dan konsentrat (rekomendasi penelitian 1). Parameter yang diukur: konsumsi dan kecernaan in vivo ransum, kondisi biologis dan konsentrasi cairan rumen, kecernaan in vitro bahan pakan dengan inokulum feses grab dan defekasi yang dikoleksi sebelum dan sesudah makan pagi dan disimpan 0, 2, dan 4 jam, efikasi inokulum feses yang diencerkan dengan aquades, NaCl-fisiologis, dan saliva buatan (buffer), serta rasio inokulum/buffer. Preparasi inokulum diaduk dengan blender dapur (30 detik), disaring dengan kain kasa 4 lapis, disentrifugasi (15 menit), dan dicampur dengan buffer sesuai kebutuhan pada setiap tahapan penelitian. Hasil penelitian disertasi ini menunjukkan bahwa konsumsi dan kecernaan ransum tidak berbeda; demikian halnya terhadap parameter kondisi biologis cairan rumen (pH, konsentrasi ammonia, total koloni, dan aktivitas carboxy methyl cellulase). Konsentrasi cairan rumen lebih tinggi setelah makan konsentrat. Nilai maksimal kecernaan in vitro pakan tropik menggunakan inokulum feses defekasi kerbau lumpur diperoleh pada dosis 350 - 423 g/L aquades dan rasio inokulum feses/buffer 1 : 2 cukup efikatif dan masih layak dimanfaatkan walaupun disimpan 2 jam dengan nilai efikasi 64,24 % terhadap cairan rumen.

The main purpose of this experiment is to study and validate efficacy of using faeces as a replacement of rumen fluid in determining in vitro feed digestibility in the tropics. Six stages of experiment were carried out to accomplish specific objectives i.e.: type of feeds and animal species, optimum level of faeces in the inoculums, time of collection, location and length of storage of faeces, type of extender and ratio of faeces to buffer. Two fistulated cows and buffaloes were consecutively fed 3 diets consisting of either 40% rice straw and 60% concentrate, 55% corn stover and 45% concentrate, or 70% elephant grass and 30% concentrate. In the following experiments, buffalo was used and fed elephant grass and concentrate according to recommendation from previous experiment. Variables measured were feed intake and in vivo digestibility of the feeds, biological conditions and concentration of the rumen fluid, in vitro digestibility of feeds using grab and defecated faecal inoculums collected before and after feeding and stored for 0, 2, and 4 hours, efficacy of faecal inoculums extended with 3 diluters (distilled water, NaCl and artificial saliva) and various ratio of inoculums to buffer. Results of the study show that the intake and digestibility of feeds and biological condition of the rumen fluid (pH, ammonia concentration, total microbial colony, and carboxy methyl cellulase activity) did not differ significantly both in cattle and buffalo. The rumen fluid concentration significantly higher after concentrated feeding. Concentrations started to decline after the second hour or after feeding concentrate, and the decline was significant after 4 hours. The efficacy of faecal inoculums defecated in the morning and stored for 2 hours at room temperature was 64.24 % or similar to the value using grab faecal of buffalo as inoculums. No significant difference were detected in efficacy of faeces diluted with distilled water, NaCl and artificial saliva. The level of faeces of 350 – 423 g/L of distilled water and inoculums to buffer ratio of 1 : 2 can be used as a medium for in vitro digestibility. This ratio has similar efficacy to the standard inoculums of feses/artificial saliva, so a modified faecal in vitro model is established.

Kata Kunci : Pakan Ternak,Kecernaan Pakan,Cairan Rumen,Feses Kerbau, In Vitro, Faeces, Rumen Fluid, Efficacy, Diluter, Tropical Feed