78 Vidad et. al./Hasanuddin J. Anim. Sci.3(2): 78-84 Apparent Metabolizable Energy of Corn and Rice Bran for Philippine Mallard Duck Sean R. Vidad 1,3* , Danilda Hufana Duran 2,3 , Joice V. San Andres 3 , Antonio J. Barroga 3 1 Department of Agricultural Sciences, Faculty of Animal Science, Mariano Marcos State University and PhD Student, Central Luzon State University City of Batac, Ilocos Norte and Science City of Munoz, Nueva Ecija, Philippines 2 Reproduction and Physiology Section, Scientist I, Philippine Carabao Center, Science City of Munoz, Nueva Ecija, Philippines 3 Department of Animal Science, Faculty of Animal Science, Central Luzon State University, Science City of Munoz, Nueva Ecija, Philippines *Corresponding author: E-mail: vidadsean@yahoo.com/vidad.sean@clsu2.edu.ph Abstract The metabolizable energy (ME) value of common feedstuffs for Philippine mallard duck (PMD) need to be established to formulate specific and balance diet for PMD. For this, the study was conducted to determine the apparent ME expressed in classical ME (AME) and nitrogen corrected ME (AMEn) of corn and rice bran for PMD. Eight PMD were used in the energy assay using the total collection method. An improvised digestibility cage was fabricated and used in the experiment modifying the basin technique in excreta collection. The homogenous wet mashes of corn and rice bran were tube-fed to the PMD twice with an interval of six hours. Excreta collection was done for 54 hours from the last scheduled tube feeding. Feed and excreta samples were sent to UPLB for protein and gross energy analyses. The experiment was carried out using the Completely Randomized Design. The calculated AME and AMEn of corn and rice bran for PMD were 3.63 and 3.61 kcal/g and 1.97 and 1.95 kcal/g, respectively. Corn tends to have a higher ME value than rice bran. The ME value of corn and rice bran for PMD is greater than the data of PHILSAN, which is the reference standard for poultry and livestock nutrient requirements in the Philippines. The result show that corn and rice bran have higher energetic value for growing PMD than book values for poultry. PMD is efficient in utilizing the energy content of corn and rice bran as manifested by the higher ME value. Keywords : Metabolizable energy, Corn, Rice bran, Mallard duck INTRODUCTION Duck production in the Philippines is considered a specialized poultry enterprise that focuses on egg production that supplies a niche market of “balut” (an embryonated egg of 16-18 days old) and salted eggs. Mallard duck or “itik” is mainly raised for thi s purpose and traditionally reared in the backyard by rural households and integrated into the existing crop Open Access Hasanuddin J. Anim. Sci. Vol. 3, No. 2:78-84 November 2021 pISSN 2621-9182 eISSN 2621-9190 DOI:10.20956/hajas.v3i2.19173