AGRICULTURAL RESEARCH COMMUNICATION CENTRE www.arccjournals.com/www.ijaronline.in *Corresponding author’s e-mail: gerardo.pamanes@gmail.com 1 Facultad de Medicina Veterinaria y Zootecnia, Universidad Juarez del Estado de Durango. Carr Durango – Mezquital km 11.5, 34307. Durango, Mexico. 2 Facultad de Zootecnia y Ecologia, Universidad Autonoma de Chihuahua. Periferico Francisco R Almada km 1, 33820. Chihuahua, Mexico. Indian J. Anim. Res., 52(9) 2018: 1298-1303 Print ISSN:0367-6722 / Online ISSN:0976-0555 Effect of inclusion of graded level of water hyacinth on in vitro gas production kinetics and chemical composition of alfalfa hay based beef cattle diets Manuel Murillo-Ortiz 1 , Esperanza Herrera-Torres 1 , Agustin Corral-Luna 2 and Gerardo Pamanes-Carrasco 1 * Facultad de Medicina Veterinaria y Zootecnia, Universidad Juarez del Estado de Durango. Carr Durango – Mezquital km 11.5, 34307. Durango, Mexico. Received: 08-01-2016 Accepted: 13-06-2016 DOI: 10.18805/ijar.11417 ABSTRACT The aim of this study was to evaluate the inclusion of water hyacinth (WH) as a possible substitution of alfalfa hay (AH) in diets of beef cattle on in vitro methane production, gas kinetics and chemical composition. AH in the diets was substituted by WH at 0% (T1, as a control), 25% (T2), 50% (T3), 75% (T4) and 100% (T5). Methane, CO 2 and gas production parameters were recorded after 24 and 48h of incubation. NDF, condensed tannins and total phenolic compounds increased when AH was substituted. Likewise, the net gas production decreased linearly when AH was substituted. However, gas production rate among treatments were similar. Methane and CO 2 production decreased linearly with inclusion of WH. These results indicate that WH arises as a promising alternative for mitigating methane production in ruminants. Key words: Condensed tannins, Gas production, Methane, Ruminants, Water hyacinth. INTRODUCTION Gases, like methane and carbon dioxide (CO 2 ) are mainly responsible for greenhouse effect and climate variations (IPCC, 2007). Methane released from livestock production and associated activities are estimated to account approximately 30% of anthropogenic emissions of methane (Steinfield et al., 2006). On the other hand, methane burning potential is 25 times more than CO 2 . Methane, as an end product in ruminal enteric fermentation, represents a loss in feed energy for the animal estimated about 10%, which can be used by the animal for production (Johnson and Johnson, 1995). Different strategies adopted to improve ruminal fermentation are dietary manipulation in animals, decreasing methane emissions by inhibiting methanogenic microorganisms and increasing energy use from feed (Beauchemin et al., 2008; Hristov et al., 2013). Condensed tannins (CT) are secondary metabolites which are synthetized in cell walls and several parts of plants (Leinmuller et al., 1991). These metabolites are often used as supplements in ruminants feeding to improve liveweight gain, digestive utilization of feeds, milk production and to prevent diseases like bloat (Min et al., 2003). Different sources have been used to obtain CT, often found in trees, shrubs and herbaceous leguminous plants (Perevolotsky, 1994; Frutos et al., 2002). Water hyacinth (Eichhorniia crassipes, WH) is an erect, perennial, stoloniferous and free-floating herb (Center et al., 2002), which it is regarded as a pan-tropical aquatic plant, spread all over the planet and being considered as one of the most problematic weed of the world (Parsons and Cuthbertson, 2001; OEPP/EPPO, 2008). Under appropriate conditions WH is able to double its number of plants within weeks, presenting a propagation rate of 15% of its superficial area per day (Majid, 1986). There are number of reports available in the literature about secondary metabolites present in WH which reported concentrations of CT ranging from 8 to 27 g/kg DM, making of it a good source of CT (Mako et al., 2011, 2012). We hypothesized that the inclusion of WH as a substitute of alfalfa hay may reduce the in vitro gas and methane production of diets consumed by beef cattle. Therefore, the aim of this study was to evaluate the inclusion of WH as a possible substitution of alfalfa hay in diets of beef cattle, on in vitro gas and methane production. MATERIALS AND METHODS The study was performed in the Faculty of Veterinary Medicine and Husbandry at the Durango State Juarez University, located in Durango, Mexico. WH was acquired from a river located in Durango, Mexico. Roots were removed and plants were washed and dried in a forced convection air oven set at 50°C for 48h. Alfalfa hay, grounded corn, cottonseed meal and minerals premix were purchased from a local store. The experimental diets were formulated to meet beef cattle nutritional requirements according to AFRC (1995) with 50% concentrate and 50% forage. Four substitution levels of alfalfa hay (AH) were evaluated in the experiment. The dietary treatments were evaluated only for the substitution of forage part by WH without altering