ORIGINAL ARTICLE Effects of hybrid and bacterial inoculation on fermentation quality and fatty acid profile of barley silage Dong Hyeon KIM, 1,2 Sadar M. AMANULLAH, 3 Hyuk Jun LEE, 1 Young Ho JOO, 1 Ouk Kyu HAN, 4 Adegbola T. ADESOGAN 2 and Sam Churl KIM 1,2 1 Division of Applied Life Science (BK21Plus, Institute of Agriculture and Life Science), Gyeongsang National University, Jinju, 4 National Institute of Crop Science, RDA, Suwon, South Korea; 2 Department of Animal Sciences, IFAS, University of Florida, Gainesville, FL, USA; and 3 Bangladesh Livestock Research Institute, Savar, Dhaka, Bangladesh ABSTRACT This study estimated the effects of hybrid and bacterial inoculant on fermentation quality and fatty acid profile of bar- ley silages. Yuyeon (Silkless) and Youngyang (Silking) barley hybrids were harvested at 24.9 and 27.1% dry matter, respectively, and chopped to 10 cm lengths. Each hybrid was treated with or without an inoculant (2 9 10 4 colony- forming units/g of Lactobacillus plantarum). A total of 48 silos were prepared in an experiment with a 2 9 2 (hy- brid 9 inoculant) treatment arrangement with four replications and three ensiling durations (2, 7 and 100 days). After 100 days of ensiling, Yuyeon silage had higher (P < 0.05) in vitro dry matter digestibility and C18:3n-3 than Young- yang silage. Youngyang silage had higher (P < 0.05) acetic acid and C18:2n-6 than Yuyeon silage. Inoculation reduced the C18:3n-3 concentration of both hybrids and increased (P < 0.05) the C18:2n-6 of Youngyang. However, fermenta- tion quality was not improved by the inoculant. These results indicate that Yuyeon hybrid might have better potential benefits on animal performances due to its smooth awn and silkless nature, and higher in vitro dry matter digestibility. Its higher C18:3n-3 would be better for improving fatty acid profile of meat or milk than Youngyang hybrid. Key words: barley silage, fatty acid, fermentation quality, inoculant, silkless. INTRODUCTION Barley is one of the most common winter forage and is ideal for ensiling because of its high water-soluble carbohydrates (17–32%) and low buffering capacity (Acosta et al. 1991; McAllister et al. 1995; Hargreaves et al. 2009). Consequently, the area of barley cultiva- tion is increasing in South Korea and recently new hybrid varieties were developed, Yuyeon and Young- yang, which are silkless and silking types, respec- tively. Silking varieties of barley are characterized by a rough and spiky texture, which could possibly reduce palatability. Park et al. (2008) reported that beef cattle fed Yuyeon silage instead of Olbori silage, which is a ‘rough awn’ silking hybrid, improved feed intake and daily gain by 14% and 35%, respectively. During ensiling, accumulation of lactic acid is required for inhibiting microbial metabolism and pre- serving nutrients (Zahiroddini et al. 2004; Hargreaves et al. 2009). However, ensiling is often unpredictable due to variation in epiphytic bacterial populations and chemical compositions of forages. The purpose of adding a microbial inoculant to silage is to stimu- late rapid growth of homofermentative lactic acid bacteria (LAB) to improve the fermentation and reduce variation in the ensiling process (Kung & Ranjit 2001). Lactic acid accumulation in silage reduces pH to a level that inhibits the growth of spoilage organisms and decreases dry matter (DM) and nutrient loss (Seale 1986). Experiments have shown that LAB-based inoculants can improve the fermentation of barley silage (Baah et al. 2011) and increase the digestibility, nutrient intake and average daily gain of cattle fed the inoculated silage (McAllister et al. 1995, 1999). However, the effects of inoculants on silage quality are inconsistent as no changes were observed on fermentation (Amanullah Correspondence: Sam Churl Kim, Division of Applied Life Science (BK21Plus, Insti. of Agri. & Life Sci.), Gyeongsang National University, Jinju 52828, South Korea. (Email: kimsc@gnu.ac.kr) Received 30 January 2017; accepted for publication 9 August 2017. © 2017 Japanese Society of Animal Science Animal Science Journal (2017) , – doi:10.1111/asj.12923