The Study Of Feed Associative Effects Based On GI And CBI Theories In Ruminants

This paper determined the general nutrient components and CNCPS (Cornell NetCarbohydrate and Protein System for Cattle) indicators of ruminant commonly feed which werecollected from9regions in Heilongjiang province. These feed samples include four types of12forage and six types of18concentrate. The nutritional value of these feed samples wereevaluated by CNCPS. And used GI (forage grading index) evaluated the quality of12forages inthe four types. Used artificial rumen continuous fermentation method evaluated thefermentation indices of4forages and4GI optimization forage mixed diets in vitro, andselected the optimal forage mixed diet. Used the nylon bag method and three-step method invitro studied the influence of GI optimization forage and concentrate mixed diet with differentCBIR(carbohydrates balance index) level for rumen nutrients degradation and the smallintestine digestibility. The results of this paper has five aspects:(1) Determined the general nutrient components and CNCPS indicators of four typesforage and six types concentrate ruminant commonly feed in Heilongjiang province, and usedCNCPS evaluated theirs nutritional value.(2) Determined the GI of12forages in the four types which were collected from differentregions of Heilongjiang province. And used the GI evaluated theirs quality. According GI theorder from high to low were: Qiqihaer alfalfa>8511farm alfalfa>Zhaodong alfalfa; Zhaodongcorn silage>Jianshan corn silage>Qiqihaer corn silage; Qiqihaer Chinese wildrye>ZhaodongChinese wildrye>Jianshan Chinese wildrye; for sheep,8510farm corn stalk>8511farm cornstalk>Ning’an corn stalk; for dairy cattle,8510farm dairy cattle>Ning’an dairy cattle>8511farm dairy cattle.(3) The results of four forages fermentation indices were evaluated by artificial rumencontinuous fermentation method in vitro（the order from high to low）: a) the pH at each timepoint: Zhaodong Chinese wildrye>8511farm alfalfa>8511farm corn stalk>Jianshan corn silage;b) the cumulation gas production, NH3-N concentration, DM and NDF disappear rate at eachtime point:8511farm alfalfa>8511farm corn stalk>Zhaodong Chinese wildrye>Jianshan cornsilage; c) the change rule of VFA concentration for4forages at each time point were differents.Integrated the rumen fermentation indicators, the nutritional value of four forages from high to low order was:8511alfalfa silage>jianshan corn silage>zhaodong Chinese wildrye>8511farmcorn stalk. The results was consistent with the results through GI evaluation.(4) According GI to preliminary screen the forage mixed formula, selected fouroptimization formula: formula1, corn silage+Chinese wildrye (90:10); formula2, cornsilage+alfalfa (85:15); formula3, corn silage+Chinese wildrye+alfalfa (70:5:25); formula4,corn silage+Chinese wildrye+alfalfa+corn stalk (80:5:10:5). The results of4formulasincubated individually were evaluated by artificial rumen continuous fermentation method in48hours in vitro: a) the pH: formula4and formula3are higher than formula1and formula2; b)the cumulative gas production: formula4> formula3> formula2> formula1; c) the DMdisappearance rate: formula4> formula2> formula3> formula1; d) the NDF and ADFdisappearance rates: formula4> formula3> formula2> formula1; the change rule of NH3-Nand VFA concentration have not obviously difference between four formula. Integrated theserumen fermentation indicators in vitro, formula4and formula3were better than formula1andformula2, and formula4was the optimal formula in the four GI optimization forage mixedformulas.(5) With the same concentrate and formula4mixed in different proportions to get3CBIRlevels forage and concentrate mixed diet, namely formula A (CBIR=2.74), formula B(CBIR=2.04) and formula C (CBIR=1.48). Used the nylon bag method and three-step in vitro methodevaluated the rumen nutrients (include DM, NDF, ADF and CP) degradation and the smallintestine digestibility of the three formulas. The results showed that: formula C> formula B>formula A. This experiment suggested that the rumen degradation rate and the small intestinenutrient digestibility of diet were negatively correlatied with the CBIRlevel of diet when theCBIRlevel of diet in the range of1.48~2.74. The diet CBIRlevel was negatively correlatedwith their concentrate content, and positively related to the content of forage.The purpose of this experiment was to use GI and CNCPS to evaluate the nutritional valueof ruminant commonly feed in Heilongjiang province. The innovation of this paper was tocombine GI with CBI theory to scientifically collocating and optimal screening ruminant mixeddiets.