EFFECT OF ENERGY AND PROTEIN RICH FEED ON IN VITRO METHANE PRODUCTION OF BLACK BENGAL GOAT

Abstract

This research was conducted to investigate in vitro methane production of feed ingredients in goat and relationship between proximate components and methane production. Feed ingredients were collected from local market of sylhet. Broken rice, rice polish and wheat bran were grouped as energy rich concentrate and red lentil (Lens culinaris), grass pea (Lathyrus sativus), mung bean (Vigna radiate) and mustard oil cake (Brassica juncea) were grouped as protein rich concentrate and chemical analysis of each sample was performed for determination of DM%,OM%,CP%,CF%,ASH%,EE% and NFE% of the samples. Rumen fluid from Black Bengal goat was collected immediately after slaughtering from slaughter house of sylhet during the experiment. Grinded 0.3 g of each feed sample was separately weighted by electric balance and taken into syringes .They were placed on a stand and put into the water bath by maintaining the temperature (39±.5)°C. According to the change in the piston position gas production was measured at 24 and 48 h of incubation. After incubation, the content of the syringe was transferred into a centrifuge tube and centrifuged at 3000 rpm for 10 min and after that IVDMD% was estimated. Within the group of energy rich concentrate, gas (151.67 ml/g DM) and methane (66.80 ml/g DM) production from broken rice and was the highest, followed by 139.96 ml/g DM gas and 54.65 ml/g DM methane by wheat bran and 49.95 ml/g DM gas and 14.42 ml/g DM methane by rice polish. Within the protein rich concentrate group, grass pea produced the highest amount of gas (142.78 ml/g DM) and methane (59.96 ml/g DM) followed by 137.10 ml/g DM gas and 51.68 ml/g DM methane by mung bean, 136.55 ml/g DM gas and 50.38 ml/g DM methane by red lentil and 130.12 ml/g DM gas and 43.42 ml/g DM methane by mustard oil cake. Methane production from each feed ingredient was decreased with increasing amount of crude fiber (CF) and ether extract (EE), whereas positive relationship was noted with the concentrations of N-free extract (NFE) and crude protein (CP). It seems possible to predict methane production potential from nutritional composition of the ingredients for their effective application on formulating less methane emitting rations. Feed stuffs which have higher gas production and IVDMD% tend to have higher CH4 production per gram DM incubated.