Abstract:

To provide a scientific basis for the preparation of dairy diet, the dried distillers grains with soluble (DDGS) samples collected were used to evaluate the ruminal degradation rate in cow. Four ruminally cannulated Chinese Holstein dairy cows in dry period were used to determine the ruminal degradation rate of DDGS of various sources with nylon bag technique. Results showed that dry matter (DM) was about 90% for most of the DDGS samples, crude protein (CP) differed from different plants (26.4% to 32.5% CP).Ruminal degradation parameter of DM of DDGS differed between different pants. The water-soluble fraction of DM was greatest for HB2 and HLJ2, lowest for HN and TJ and mid for other samples. The degradable fraction of DM was lower for HLJ1, HLJ2, HB1 and HB2 with about 60%, and higher for TJ, AH and HN with about 75%.〖HT〗〖ST〗〖WT〗〖HJ〗

〖WT5”BZ〗The degradation rate of degradable fraction ranged from 0.025% to 0.044 h-1.Effective degradation rate of DM ranged from 41.0% to 58.2%. Water-soluble fraction of CP was about 17%, except TJ with 3.3%. Degradable fraction of CP was the least for HB1 and HLJ1 with 58.7%, and greatest for HB2 and HLJ2 with 82.2% and 82.1%. The degradation rate of degradable fraction of CP ranged from 0.013 to 0.035 h-1. The effective degradation rate of CP ranged from 22.5% to 53.4%. In concern with the nutritional characteristic and ruminal degradation parameter of DDGS differed largely in various plants, it would be effective to develop a quick and easy test technique to determine the feed value of the DDGS that could be used by the farmer. Then a more efficient use of nitrogen was to reduce wastage of feed resources.

Key words: dairy cow; DDGS; ruminal degradation rate