NE US Academic Publishers Advances in Animal and Veterinary Sciences September 2020 | Volume 8 | Issue 8 | Page 813 INTRODUCTION I n the non-tidal swamp of South Sumatra, the forage supply mainly depends on aquatic vegetations, one of them is Kumpai grass (Hymenachne amplexicaulis (Rudge) Nees). However, the utilization of Kumpai grass is limited by the high fber fraction that may reduce intake and digestibility when fed alone in the diet (Ali et al., 2013; Rostini et al., 2014). Te high price of concentrate was the main reason for the low frequency of cattle supplementation by smallholder farmers (Hernaman et al., 2018; Mumba et al., 2018). Concerning the price of commercial concentrate, the locally-available concentrate may increase cattle performances and farmer income. Palm oil sludge (POS) is one of the agro-industrial by-products from palm oil processing at a low price and available for small scale farming. Te supplementation of POS has a potency for increasing intake and cattle performance due to a higher content of water-soluble carbohydrates and a source of unsaturated fatty acids (Hayyan et al., 2010) that might reduce methane gas production (Machmüller et al., 2000; Vlaeminck et al., 2006). An often-used approach for boosting cattle production in humid tropical areas was cassava leaves since a higher crude protein (CP) content, especially branched amino acids. Furthermore, Te addition of branched amino acids in the ration was able to increase Research Article Abstract | Utilization of potential swamp forages, by-product of the palm oil industry, and cassava is a strategy in the improvement of cattle feed. Te purpose of this study was to evaluate the efect of cassava leaves, palm oil sludge, and yeast supplementation on a ration based on Kumpai grass (Hymenachne amplexicaulis (Rudge) Nees) on the performance of Bali heifers. Twelve Bali heifers were allocated into two groups. First group was fed with control diet consisting of 70% Kumpai grass + 30% concentrate (R0) while second group (R1) was fed a diet consisting of 55% Kumpai grass + 15% concentrate + 15% palm oil sludge (POS) + 15% cassava leaves + 5 g yeast (Saccharomyces cerevisiae)/head/d. Te variables measured in this study were intake, digestibility of dry matter, organic matter, crude protein, neutral detergent fber, acid detergent fber, average daily gain, feed conversion ratio, and farmer income. Data were analyzed by independent t-test. Te results showed that the supplemented diet had a signifcant performance by improving the intake of dry matter, organic matter, and crude protein. Moreover, it also followed by increasing the digestibility of dry matter, organic matter, crude protein, neutral detergent fber, and acid detergent fber, average daily gain, feed conversion ratio, and farmer income. Supplementation of palm oil sludge, cassava leaves, and yeast in the Kumpai grass-based ration signifcantly increased the performance of Bali heifers. Heifers fed the supplements gave a higher income than those without supplements. Keywords | Bali heifers, Digestibility, Daily gain, Non-tidal swamp, Performance RISWANDI*, BASUNI HAMZAH, AGUS WIJAYA, ARFAN ABRAR Bali Heifers Performance on Cassava Leaves, Palm Oil Sludge and Yeast Supplementation in a Ration Based on Kumpai Grass (Hymenachne amplexicaulis (Rudge) Nees) Received | February 24, 2020; Accepted | June 28, 2020; Published | July 15, 2020 *Correspondence | Riswandi, Sriwijaya University, Indonesia; Email: riswandi_dya@yahoo.com Citation | Riswandi, Hamzah B, Wijaya A, Abrar A (2020). Bali heifers performance on cassava leaves, palm oil sludge and yeast supplementation in a ration based on kumpai grass (Hymenachne amplexicaulis (Rudge) Nees). Adv. Anim. Vet. Sci. 8(8): 813-818. DOI | http://dx.doi.org/10.17582/journal.aavs/2020/8.8.813.818 ISSN (Online) | 2307-8316; ISSN (Print) | 2309-3331 Copyright © 2020 Riswandi et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Sriwijaya University, Indonesia.