Chemical composition and digestibility of urea-calcium hydroxide treated barley straw, date palm frond and corn cobs with and without molasses

Abstract

The objective of this work was to study the effect of supplementation molasses to urea-calcium hydroxide treated barley straw, date palm frond and corn cobs, using urea (0, 2, 4 and 6%) plus calcium hydroxide (0, 2, 4 and 6%). within an ambient temperature range from 30 - 37Co with a storage time of 3 week (4 treatments) then supplement with 10% molasses on dry matter basis. Treated barley straw with urea and calcium hydroxide affected significantly (P<0.01) the nitrogen content from 5.43 to 11.28 g/ kg DM, Dry matter In vitro digestibility (IVDMD) from 39.110 to 43.646% and Organic matter In Vitro digestibility (IVOMD) increased from 40.055 to 42.305%, the metabolizable energy (ME) was increased from 6.01 to 6.05 MJ/kg DM and total digestible nutrient (TDN) improved from 43.43 to 50.98%, the lignin content was decreased significantly (P<0.01) from 88.710 to 66.343 g/ kg DM. Furthermore the best treatment which gave better improvement in nitrogen content, IVDMD, IVOMD, TDN and ME was associated with combination of 6% urea and 6% calcium hydroxide. It was found that date palm frond treated with urea and calcium hydroxide brought about increased significantly (P<0.01) nitrogen content from 1.50 to 11.58 g/ kg DM, IVDMD from 30.661 to 43.480%, IVOMD from 36.495 to 42.210% and ME from 5.48 to 6.33 MJ/ kg DM, the lignin content was lower (P<0.01) from 107.500 to 98.591 g/ kg DM. 4% urea plus 4% calcium hydroxide treated date palm frond were effective in increasing (P<0.01) IVDMD, IVOMD and ME. Treatment corn cobs with urea and calcium hydroxide improved (P<0.01) the nitrogen content (from 0.57 to 10.43 g/ kg DM), IVDMD (from 28.091 to 36.591%), TDN (from 45.26 to 46.97%), IVOMD and ME increased (P<0.05) from 35.207 to 38.669% and 5.28 to 5.80 MJ/ kg DM respectively, while lignin content was lower (P<0.05) from 54.211 to 50.868 g/ kg DM. A level of 6% urea and 6% calcium hydroxide treated corn cobs significantly increased the nitrogen content, IVDMD, IVOMD and ME. The result indicated that the effect of supplementing 10% molasses to barley straw, date palm frond and corn cobs with level 4 and 6% of the best urea and calcium hydroxide treatment respectively improved nitrogen content, IVDMD, IVOMD and ME.