Determination of chemical composition and gross energy of cereal straw (Wheat & Barley)in Kermanshah province

In order to prepare standard tables of chemical composition of feedstuffs in Iran, this reseach was carried out on Wheat straw and Barley straw in Kermanshah provine. In order to determine their chemical composition and gross energy, 68 samples of Wheat straw(1 th year,30, 2th year.l8 and 3th year.20) and 66 samples of Barley straw(lth year.30, 2th year.16 and 3th year.20) were collected according to the probability stratified random sampling method.The samples of 1375(1996) were determind based on standard deviation and 5% error of mean of crude fibre content in samples of 1372(1993).1n this way sample size of 1376(1997) were determined based on results of samples of 1375(1996) also. The collected samples each village consist of 3 fanners which were chosen incidentlly and then the samples were tkaen from their farms. Ultimately 134 samples were taken for chemical analysis, include crude protein, crude fibre, ether extract, ash, groos energy, N.F.E, macro elements (Ca, P,.K, Na & Mg) and micro elements (Fe, Mn, Cu & Zn). The mean, standard deviation, rang and coefficient of variation (c.V) of nutrients and mineral contents and also the correlation coefficient between the nutrients in each of feedstuffs were calculated. The average crude protein, crude fibre, ether extract, ash and N.F.E contents for Wheat Straw were 3.32, 38.96, 0.84, 9.19 and 47.70 percent respectively and for Barley Straw were 3.84, 37.11, 1.10, 10.90 and 47.36 percent respectively. The average gross energy content for Wheat and Barley Straw were 4105.10 and 4083.19 KcaJ/kcal/Kgr/DM respectively.The average Calcium, Phosporous, Potassium, sodium and Magnesium cotents for Wheat Straw were 0.44, 0.09, 1.35, 0.06 and 0.17% and for Barley Straw were 0.76, 0.10, 1.49, 0.12 and 0.23 percent respectively. The average content of Iron, Manganese, Copper and Zinc were 649.74, 57.80, 5.19 and 21.79 PPM/DM for Wheat Straw and for Barley Straw were 1023.35, 57.57. 5.91 and 29.20 PPM/DM respectively.