Determination of the metabolizable energy (ME) and net energy lactation (NEL) contents of some feeds in the Marmara Region by in vitro gas technique

Abstract

In this study, chemical composition and energy values of some forages, raw materials and commercial feeds commonly used in the Marmara Region for ruminants were determined. Samples of sunflower meal, barley, wheat, oat, corn, wheat bran, grass hay, vetch hay, alfalfa hay and compound feeds were collected for evaluation.The samples of feed were analyzed for their chemical composition. Gas production capacity, in vitro organic matter digestibility and energy values of feeds were studied by Hohenheim Gas Test. The feed samples were incubated with rumen liquor for 24 hours and net gas production was computed. Digestibility values of organic matter and energy content were calculated.Variation in the chemical compositions was observed among forages at 3.23% to 20.89% for crude protein, 21.75% to 50.16% for crude fiber, 0.15% to 4.61% for ether extracts. In grains, crude protein ranged from 9.26% to 12.3%, crude fiber from 4.11% to 11.66%, and ether extract from 1.72% to 4.49%. The values of crude protein, crude fiber and ether extract in commercial dairy cows and beef cattle feed varied between 13.66% and 21.91%, 3.48% and 13.18%, and 2.09% and 6.60%, respectively. Net gas production value of forages was found between 12.38 and 52.54 ml/200 mg DM. ME and NEL contents of forages ranged from 3.07 to 10.22 MJ/kg DM and from 1.08 to 6.24 MJ/kg DM, respectively. The average gas production of oat, barley, wheat and corn was 59.20, 63.59, 68.00 and 67.94 ml/200 mg DM. Calculated ME and NEL values of corn, wheat, barley and oat by in vitro gas production were 13.08, 12.99, 12.45 and 12.10 MJ/kg DM and 8.30, 8.25, 7.84 and 7.55 MJ/kg DM, respectively. Net gas production of beef cattle feed and dairy feed was 51.48 ml/200 mg DM and 51.59 ml/200 mg DM. ME and NEL values of these feeds were 9.23-12.99 and 5.43-8.20 MJ/kg DM for beef cattle and 9.74-12.67 and 5.76-7.89 MJ/kg DM for dairy cattle feed.In this study, the nutrient composition and energy values of feedstuffs commonly grown or produced in the Marmara Region were tabulated. The results should help us better understand the nutrition potential of such feedstuffs and provide basic information in ruminant feeding.