Study On The Bioassay Method Of Metabolisable Energy Of Feedstuffs For Geese

Two metabolisable experiments were taken on Yangzhou geese to study the duration of starvation priors and excreta collection periods and feed input level for true metabolisable energy measurement. Then the metabolisable regularity of different nutrition ingredients and the metabolisable values of 6 feedstuffs(Corn, Soybean, Wheatbran, Paddy, Cotton-seed, Alfalfa)were detected with condign fasting priors and correct fecal collection periods and feed intake level. The results showed that:1 .The amount of dry matter(DM) excretion was reduced and the feed metabolic ratio and Apparent Metabolisable Energy(AME),True Metabolisable Energy(TME) values was increased with the progressing of fasting time. Among them the Metabolisable Energy(ME) values of fasted 40h group were highest. The results of analysis showed that: there were no significant difference of the AME and TME values of 24, 32, 40h fasted treatment.2.The amount of dry matter excretion increasing and the digestibility of dry matter and the AME,TME values decreasing with the prolonging of the excreta collection time. Except the AME values of 24h fecal collection time were significant higher than that of 48h, there were no obvious difference between 24, 32, 40, 48h clearance time. The TME values of 16, 24, 32, 40, 48h collection time showed no apparent difference.3.The dry matter excretion and excreta energy of Corn-Soybean meal diet(dietl) and Corn-Soybean-Wheat bran meal diet (diet3) decreasing with the increasing of feed input level, the 100g forced feed group were lowest. However, the ME values extending with the- increasing of feed input level. Except the AME values of 60g gavage group were significant lower than that of 100g gavage group, there were no clear distinction between 60g and 80g and 100g gavage group. There were not significant difference ofTME among all gavage group.The digestibility of energy of Corn-Soybean-Alfalfa meal diet(diet2) decreased at first and then increased varied with input level. The 100g gavage group higher than that of 80g gavage group. The ME values demonstrate a opposite trend, The AME and TME values of 80g gavage group was highest, and significantly higher than that of 60g gavage group, but close to 100g gavage group. The AME and N-corrected apperant metabolisable energy(AMEn) of 80g gavage group were obvious higher than that of 60g gavage group, But there no evident difference between 100g and 80g,100g and 60g gavage groups. The TME and N-corrected true metabolisable energy(TMEn) values change with the feed input level, but there were no significant difference among 100g, 80g, 60g gavage groups.4.The availability efficiency of nutrition in feedstuffs different with the feedstuffs and diet's composition different, the metabolic ratio of dry matter, gross energy(GE), crude protein(CP), Acid detergent fibre(ADF), Ash in Corn, Paddy, Wheat-bran were higher than that of Soybean, cottonseed. So was the ME values. Alfalfa had the lowest ME values as we had predicted.5.The ME values had a negative correlation with feedstuffs' other determinate components, the strong negative correlation exists between ME values and DM, ADF, ash. Except had a negative correlation with neutral detergent fibre(NDF), GE and CP showed a positive correlation with feedstuffs' other ingredients. GE had a strong correlation with CP, but weak correlation with other nutrition.6.The regression analysis indicted that: Ash was the most important factor to AME and TME when stepwise technique was used to choose estimate factor for regression equation. The most efficiency 1-factor linear regression equation were AME=12.81-0.70Ash; TME=13.48-0.67 Ash.According to the results of the experiments, the proper duration of starvation and excreta collection period of bioassay of TME in geese is 24+24h. The optimal feed input was80~100g.