Limited data are available regarding the effects of Brachiaria decumbens on sheep's growth performance at different times. Therefore, this current study focused on sheep's nutrient apparent digestibility, feed efficiency, body index, and growth hormone when they are fed with low and high levels of B. decumbens diets. A total of 30 six-month-old male Dorper cross sheep were divided randomly into three treatment groups with 10 sheep per treatment. Treatment 1 (control) sheep were fed with Pennisetum purpureum and pellets as the basal diet, whereas Treatment 2 and 3 sheep were fed with feed mixed with low (10%) and high (60%) levels of B. decumbens, respectively. The study was conducted in two phases consisting of short-term feeding (seven days) and long-term feeding (90 days). Throughout the experiment, daily fecal voided were collected in the morning for seven days continuous before the end of each feeding phases for the determination of nutrient apparent digestibility. The amount of feed offered and refusals plus body weight gain were recorded daily to determine the feed efficiency (FE). Besides, the body measurements of each sheep from every treatment were measured weekly and blood samples were collected for the analysis of growth hormone (GH) concentration. There were significant differences (p < 0.05) in the nutrient apparent digestibility, growth performance, body measurement, and GH concentration among treatment sheep throughout the study period. Treatment 3 sheep fed with 60% of B. decumbens diet revealed the lowest dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility during the long-term feeding. Likewise, Treatment 3 (T3) sheep had the lowest total bodyweight gain, average daily gain, total feed intake, and daily feed intake among treatment sheep. The heart girth index (HGI) of T3 sheep was also significantly lower during the short-term feeding. Moreover, the GH concentration of T3 sheep was significantly lower as compared to the control that decreases steadily throughout the study period. In conclusion, high levels of B. decumbens showed the most significant results out of all three treatments indicating the presence of saponins, which produce negative effects on the sheep's overall performance.
Data tersedia mengenai kesan jumlah Brachiaria decumbens yang berbeza terhadap prestasi pertumbuhan biri-biri pada tempoh masa yang berbeza adalah terhad. Oleh itu, kajian semasa ini memberi tumpuan kepada kebolehcernaan ketara nutrien, kecekapan makanan, indeks badan, dan hormon pertumbuhan bebiri yang diberi makan dengan diet B. decumbens pada tahap rendah dan tinggi. Sebanyak 30 ekor bebiri Dorper jantan berumur 6 bulan dibahagikan secara rawak kepada 3 kumpulan rawatan dengan 10 ekor bebiri setiap kumpulan. Rawatan 1 (kawalan) bebiri diberi makan dengan Pennisetum purpureum dan pelet sebagai diet asas, manakala bebiri Rawatan 2 dan 3 masing-masing diberi makan dengan campuran B. decumbens pada tahap rendah (10%) dan tinggi (60%). Kajian ini dijalankan dalam dua fasa yang terdiri daripada pemakanan jangka pendek (7 hari) dan panjang (90 hari). Sepanjang eksperimen, najis harian yang dibuang dikumpulkan pada waktu pagi selama 7 hari berterusan sebelum tamat setiap fasa pemakanan untuk menentukan kebolehcernaan ketara nutrien. Jumlah makanan yang diberi, sisa makanan, dan penambahan berat badan direkodkan setiap hari untuk menentukan kecekapan makanan (FE). Selain itu, ukuran badan setiap bebiri daripada setiap rawatan diukur setiap minggu serta sampel darah diambil untuk analisis kepekatan hormon pertumbuhan (GH). Terdapat perbezaan yang signifikan (p < 0.05) dalam kebolehcernaan ketara nutrien, prestasi pertumbuhan, ukuran badan, dan kepekatan GH di kalangan bebiri rawatan sepanjang tempoh kajian. Bebiri rawatan 3 (T3) yang diberi makan dengan 60% diet B. decumbens menunjukkan kebolehcernaan bahan kering (DM), protein kasar (CP), gentian detergen neutral (NDF), dan gentian detergen asid (ADF) yang paling rendah semasa pemberian makanan jangka panjang. Bebiri T3 mempunyai jumlah penambahan berat badan, purata kenaikan harian, jumlah pengambilan makanan, dan pengambilan makanan harian yang paling rendah di kalangan bebiri rawatan. Indeks lilitan jantung (HGI) bebiri T3 juga jauh lebih rendah semasa pemberian makanan jangka pendek. Selain itu, kepekatan GH bebiri T3 adalah jauh lebih rendah berbanding dengan bebiri kawalan yang menurun secara berterusan sepanjang tempoh kajian. Kesimpulannya, tahap B. decumbens yang tinggi menunjukkan keputusan yang paling ketara daripada ketiga rawatan yang menunjukkan kehadiran saponins boleh menghasilkan kesan negatif terhadap prestasi keseluruhan bebiri.
Keywords: Body Index; Dorper; Feed Efficiency; Growth Hormone; Hormon Pertumbuhan; Indeks Badan; Kebolehcernaan Ketara Nutrien; Kecekapan Makanan; Nutrient Apparent Digestibility; Saponin; Saponins.
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