Effect of feeding complete ration based on urea treated wheat straw on nutrient utilization and rumen fermentation pattern in crossbred cattle

摘要

In order to study the comparative effects of feeding systems with and without green fodder on nutrient utilization and rumen fermentation, 3 rumen fistulated male crossbred cattle (2.5 to 3 years age and average body weight of 350 kg) were fed 4 dietary treatments, viz. treatment I (conventional feeding system with green fodder), treatment 2 (complete feed with green fodder), treatment 3 (conventional feeding system without green fodder) and treatment 4 (complete feed without green fodder) in a switch over experiment for 4 periods. The total dry matter intake in cattle fed ration containing green fodder was more than those fed ration without green fodder. The daily digestible crude protein (DCP) intake (0.96 kg) was significantly higher while TDN intake (4.44 kg) was significantly lower in animals fed complete feed with green fodder (treatment 2) than other treatment groups. The digestibility of dry matter, organic matter, crude protein and crude fibre did not differ significantly among different treatments. However, the digestibilities of crude protein and crude fibre were slightly higher in crossbred cattle fed complete ration with green fodder (treatment 2) than other treatments. The total nitrogen, TCA-precipitable protein nitrogen and total volatile fatty acids (TVFA) concentration in strained rumen liquor (SRL) was significantly higher in animals fed complete feed either with green fodder or without green fodder compared to corresponding conventional feeding system. Whereas, the ammonia nitrogen concentration (mg/100 ml) was significantly higher in treatments 3 (36.89) and 4 (35.17) compared to treatments 1 (28.00) and 2 (31.20) which might be due to higher level of feeding ammoniated wheat straw. The average pH value in the SRL was significantly higher in treatment 4 compared to other treatments. The activity of ruminal enzymes, viz. (alpha-amylase, carboxymethyl cellulase, xylanase, (x-glucosidase and P-glucosidase was maximum in particulate material followed by extra cellular and cellular fraction of rumen contents and were significantly higher in animals fed complete ration with or without green fodder (treatments 2 and 4) compared to the animals fed similar conventional ration (treatments 1 and 3). The results revealed that feeding of ration as complete feed is advantageous over conventional feeding system in better utilization of different nutrients coupled with increased concentration of total nitrogen, TCA-precipitable protein nitrogen, TVFA and all the ruminal enzymes activities. Supplementation of green fodder in the ration irrespective of feeding systems further improved activities of all the ruminal enzymes. It seems that complete feed system combined with green fodder supplementation provides better condition for rumen fermentation and nutrient digestion.