The Effects of Planting Time and Combination on the Nutrient Composition and Digestible Dry Matter Yield of Four Mixtures of Vetch Varieties Intercropped With Barley

Abstract

The aim of this study was to determine the chemical composition, digestibility, energy content, and digestible dry matter yield of 4 mixtures of different vetch varieties intercropped with the same barley at 3 different planting times under Eastern Anatolian conditions. Four different vetch species, i.e. common (Farukbey-2001), Hungarian (Tarim Beyazi-98), hairy (Selcuklu-2002), and wooly pod (Segmen-2002), intercropped with barley (Tokak-157) were utilized. The mixtures of vetches intercropped with barley were planted on 7 October 2003 (I), 7 November 2003 (II), and 10 April 2004 (III), and each variety/planting time was randomly assigned to 3 replications. The mixtures of vetches intercropped with barley were harvested by hand using clippers when the barley started spiking and vetches were at 1/4 flowering. All samples were analyzed for dry matter (DM), ash, crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) content. In vitro dry matter digestibility (IVDMD) of the samples was also determined. While DM and organic matter (OM) content did not differ, CP, NDF, and AIDE content were significantly different among the different mixtures of vetch intercropped with barley (P < 0.05). IVDMD, metabolizable energy (ME), and net energy lactation (NEL) values were also significantly different among the mixtures of vetch intercropped with barley (P < 0.05). Digestible DM and ME yield of the mixtures were significantly affected by planting time (P < 0.05), but not variety. However, CP yield of the vetch-barley mixtures was significantly affected by both planting time and variety (P < 0.05). It can be concluded that all of the mixtures of vetch intercropped with barley had significantly higher digestible DM and CP yield when planted on 7 October 2003. Thus, October should be preferred for planting of the mixtures of vetch intercropped with barley in Eastern Anatolia. If a greater CP yield in addition to digestible DM yield is desired from vetch-barley hay, then common vetch should not be the choice.