PERTUMBUHAN DAN RASIO EFISIENSI PROTEIN BROILER DENGAN PEMBERIAN TEPUNG KELENJAR TIROID SAPI DALAM RANSUM PASCA PEMBATASAN PAKAN

Abstract

Cattle's thyroid-gland meal is a source of natural thyroxin hormone. The research was conducted to evaluate the responses of broiler to "cattle's thyroid-gland meal containing diet" fed post-restriction programs. The experiment used 189 days old chick broilers female. The starter and finisher diet were calculated 23% crude protein; 3,000 kcal/kg metabolizable energy and 20% crude protein; 3,000 kcal/kg metabolizable energy, respectively. The starter was fed from I to 28 days old age (DOA) and the finisher diu from 29 to 49 DOA. Split plot design with three blocks was used to arrange this experiment. The main-plot was feed restriction programs i.e. RO = ad libitum-fed, RI = 85% feed restriction and R2 = 70% feed restriction. Feed restriction programs were carried out from 8 to 14 DOA. The sub-plot was cattle's thyroid-gland meal levels in the diets i.e.TO = 0%, T2 = 0.075%, and T3 = 0.150% and fed from 15 to 28 DOA. The results showed that at first week (15-21 DOA) cattle's thyroid-gland meal increased (P<0.05) body weight gain (BW gain) and protein efficiency ratio (PER) of broilers fed ad libitum or after restricted. A second week cattle's thyroid-gland meal did not influence broiler's BW gain and PER. The cattle's thyroid-gland meal containing diet was not effective at second week (22-28 DOA), may be due to TSH fed-back mechanism. Key words: Cattle's thyroid-gland meal, feed restriction programs, broiler's performance and protein utility ABSTRAK Tepung kelenjar tiroid kering sapi (KTKS) mertipakan badan sumber hormon tiroksin, Penelitian ini bertujuan untuk mengkaji respon broiler terhadap pembatasan pakan dint dan pemberian kelenjar tiroid kering sapi (KTKS) dalam rims= pasca pembatasan pakan. Materi yang digunakan DOC broiler betina scbanyak 189 ckor. Ransum yang digunakan umur 1-28 hart adalah ransom starter (protein kasar 23% dan energi metabolis 3000 kkal/kg), sedangkan pada umur 29-49 hart diberikan ransum finisher (protein kasar 20% dan energi metabolis 3000 kkal/kg). Rancangan pereobaan yang digunakan adalah rancangan acak kelompok (RAK) dengan pola split plot. Petak utama adalah pembatasan pakan, yaitu: RO, RI. R2 masing-masing ad libitum, pembatasan pakan 85% pada umur 8-14 hart, dan pembatasan pakan 70% pada umur 8-14 hart. Anak petak adalah pemberian KTK, yaitu: TO, TI, dan T2 masing-masing 0%, 0.075%, dan 0.150% ransum diberikan pada umur 15.28 had. Basil penelitian menunjukkan seminggu pertama pemberian KTK sapi dalam ransum broiler pasca pembatasan pakan maupun pakan ad libitum akan meningkatkan (P<0,05) pertambahan bobot badan (PBS) dan ratio efisiensi protein (REP). Seminggu pemberian 0.075-0.150% KTKS dalam ransom broiler meningkatkan pertumbuhan dan penggunaan protein dengan pemberian pakan ad libitum maupun pasca pembatasan pakan 85% dan 70%. Pemberian KTK sapi dalam ransum pada minggu kedua tidak mempengaruhi PBB dan REP. Pemberian tepung KTK sapi dalam ransum broiler tidak efektif pada minggu kedua, akibat mekanisme umpan batik TSB. Kea kunci: Tepung kelenjar tiroid kering sapi, pembatasan pakan, penampilan dan penggunaan protein