The fixation of nitrogen using acid, green forage and germinated barley during urea treatment of straws

Abstract

In the treatment of gram straw hydrochloric acid had a more significant ( P < 0.01) effect than sulphuric acid in lowering the loss of ammonia nitrogen from 45.88% in control to 16.28% using 7.5% urea at a 40% (F 4) fixation level as compared with 30% (F 3), 20% (F 2) and 10% (F 1). Treatment of gram straw ( Cicer arietinum) for 28 days with 7.5% urea having 44.88% moisture at F 4 could significantly ( P < 0.01) check the loss of ammonia and enhance the crude protein (CP) content to 19.37%. In Experiment 2, the loss of nitrogen was effectively reduced from 35% (T 0) to 22% (T 1) and 21% (T 2) by means of sulphuric acid (10.18 g kg −1 dry matter (DM)) and green sorghum ( Sorghum vulgaris) mixed with wheat straw in the ratio of 1:2 at the time of storage. The relative retention of nitrogen (g day −1) in male buffalo calves was significantly ( P < 0.05) superior in T 1 (53.31) and T 2 (45.58) than T 0 (35.42). The digestible CP (DCP) and total digestible nutrient (TDN) values of urea treated wheat straw were 7.10%, 8.33%, 6.49%, 57.90%, 55.64% and 62.58% in respective treatments. During Experiment 3, untreated wheat straw plus concentrate mixture, 20% CP (T 3), urea (7.5%) treated straw, US (T 4), urea treated straw plus acid (23 g kg −1 DM) (T 5), and urea treated straw plus germinated barley 24% (T 6) were fed to buffalo calves in four groups. The daily body weight gain (g day −1) was significantly ( P < 0.01) greater in T 6 (640.15) followed by T 5 (556.80), T 4 (499.99) and T 3 (458.32). Cost per kg gain in body weight (Rs.) was minimum in T 6 (12.47) followed by T 4 (14.15), T 5 (14.99) and T 3 (23.45). The loss of nitrogen was considerably lowered from 51.3% (T 4) to 19.07% (T 5) using sulphuric acid at farm scale. Urea treated straw with 24% germinated barley, containing 13.39% CP, 8.33% DCP and 58.54% TDN, may be an economical complete ration for growing buffalo calves replacing native protein completely.