The Study On The Nutrient Composition And Rumen Degradation Characteristics Of Different Source Of Energy Feeds

Two experiments were conducted to study the compositions and the rumen degradation characteristics of the different energy feedstuffs in Xuanhan beef cattle. Firstly, nutrients composition of feed ingredients were determinated by proximate analysis method and the Cornell net carbohydrate and protein system (CNCPS).Then, nylon bag method was used to study rumen degradation characteristics of different energy feeds, and studied the difference of rumen degradation efficiency in four energy feeds. After that, the correlation between rumen degradation parameters and components of different energy feeds, and equations were established.In experiment1, Four commonly used energy feeds in Sichuan province were analyzed by feeds proximate analysis and CNCPS system. The results show that:1. The content of organic matter (OM) and starch in cereal grains energy feeds were significantly higher than bran class feed, and content of NDF lower (P<0.05) than the bran feed.2. Cereal grains energy feeds had higher (P<0.05) levels of carbohydrate (CHO), non-structural carbohydrates (NSC), sugar (CA) and starch and pectin (CB1) compared with the bran feed.3. In cereal grains energy feed, compared with the rice, corn had higher contents of CA, PA plus PB1(10.54%,9.69%), but lower contents of unavailable fiber (CC) and bound protein (PC)(P<0.05).4. CA and CB1of carbohydrate in wheat bran (12.07%,40.58%) were significantly higher than rice bran (8.91%,31.05%), CC and PC content in rice bran significantly higher (P <0.05) than wheat bran.In experiment2, the nylon bag technique was used to comparative study the rumen degradation characteristics of the different energy feeds. In this study three healthy and similar weight cattles fitted with permanent ruminal cannulae were used as test animals. Then the correlation between rumen degradation parameters and components of different energy feeds, and equations were established. The results show that:1. In the four energy feeds, the effective degradability (ED) of dry matter (DM) in corn was highest than others, and the ED of DM (62.36%) were significantly higher than those of rice (56.45%), the effective degradability (ED) of wheat bran (61.09%) were significantly higher than those of rice bran (35.06%)(P<0.05).2, In these energy feeds, cereal grain feeds had higher levels of slow degradable fraction (b) and potential degradation (a+b) of crude protein (CP) than bran feeds (P<0.05). The effective degradability of CP in corn, rice, rice bran and wheat bran were51.49%、61.73%、52.64%、72.81%.3. The fermentable organic matter of the corn was780.03g/kg, that was higher than rice (12.57%),rice bran (44.34%)and wheat bran(28.88%). The digestible energy(DE) and metabolizable energy(ME)of cereal grain feeds were significantly higher than bran feeds(P<0.05), the digestible energy of corn and rice were14.79MJ/kg and13.28MJ/kg, the metabolizable energy of corn was higher than rice(1.37MJ/kg), the digestible energy and metabolizable energy of rice bran were the lowest.4. The ruminal undegradation protein(RUP), digestible crude protein(DCP), intestine digestible protein(IDP) of corn of the cereal grain feeds (37.08%,63.08%,48.66%) were significantly higher than the bran feeds (26.28%,57.08%,42.28%)(P<0.05). The ruminal degradation protein(RDP), RUP, DCP and IDP of wheat bran (112.45%,45.14%,141.79%,100.18%) were the highest in the four energy feeds.5. The effective degradability of the DM and OM of the energy feed were a significant positive correlation with NSC and CBl,and were a significant negative correlation with CC except wheat bran(P<0.05).6. The rapid degradation part of CP was a significant positive correlation with the PA puls PB1in the CNCPS (P <0.05).Conclusions:The nutrition value of the energy feeds primarily related to the content of CA, CB1, CB2, and true protein (PB), the nutrition value of the corn was the highest in the four energy feeds, followed by the rice, wheat bran and rice bran. The degradation characteristics was different in the four energy feeds. The DM degradation rate of the corn in rumen was the highest, while the CP degradation of the wheat bran was the highest. The DE and ME of corn were the highest, while the RDP、RUP、DCP�'�IDP of wheat bran were the highest. The correlation existed between the effective degradability of common energy feeds in rumen and the NSC、CB1and CC of energy feeds.