Laboratory Studies on Ammonia (Urea) Treatment of Baled Paddy Straw for Utilization as Livestock Feed

Abstract

Ammoniation of loose straw using urea as a source of ammonia has been found to increase its nutritive value and digestibility as livestock feed. Application of this technique on baled straw would mitigate the problems associated with loose straw treatment.An experimental set-up was, therefore, developed for laboratory studies on ammonia (urea) treatment of baled straw in batches. The effects of specific amount of liquid application (725 to 1325 cc/kg DM), discharge rate of liquid applicator (500 and 1000 cc/min) and bed depth (upto 1.08 m i.e. 3 bales) were studied to establish the best application parameters for baled paddy straw. A stack of about 0.4 T of baled paddy straw having the initial moisture content 0f 8% (w.b.) and bale density of 110 kg/m³was treated with 5% ( wt:wt) urea solution at the discharge rate of 1000 cc/min, specific amount of liquid application of 1125 cc/kg DM and bed depth of 1.08 m to raise its moisture content to around 40% (w.b.) and cured for 21 days by covering it with plastic sheets to form an airtight enclosure by adopting 'Norwegian Method'. The evaluation of treated baled paddy straw showed significant (P&lt0.05) increase in in-situ dry matter digestibility coefficient by 12.52% units, crude protein content by 9.97% units and ammonical nitrogen content by 0.8% units over untreated straw which were in the normal range reported for ammonia (urea) treatment of loose straw.