Department of Animal Nutrition, College of Veterinary Science, Tirupati-517 502, India.
Online published on 5 January, 2012.
Eight conventional and seven unconventional energy sources were screened in terms of their rumen degradable nitrogen by Incubating them for 3, 6, 9, 15 and 24 h in the rumenof 5 steers fitted with rumen cannulae and maintained on a ration having roughage to concentrate ratio of 67:33. Variation in CP content reflected on the average N disappearance values throughout the rumen Incubation. Soluble fraction was ‘0’ for coffee seed husk andjnango seed kernel proteins while it was highest (45%) for Jowar grain and citrus fruit waste. Insoluble but degradable fraction along with the rate of degradation also varied widely among the various feeds. The rumen outflow rates were 0.042 and 0.052/h when the steers were fed rations containing roughage to concentrate ratios (R:C) at 67:33 and 50:50, respectively. Average effective protein degradability (EPD) values were higher by 2.28 % units when fed ration with R:C at 67:33 ratio as compared to a ratio of 50 :50. Citrus fruit waste, Jowar grain, tamarind seeds, wheat bran, DORB and oat grains with EPD of 79, 77, 71, 63, 56, and 53%, respectively appeared to be potential sources of RDN among the 15 energy sources compared. Proteins fkom salseed meal, mango seed kernel, variga, bajra and rice bran were less degradable. These results may help in formulating rations based on RDN and UDN.
