Optimization Of The A Part Of Operating Parameters Of Novel Dual-flow Rumen Simulation System

At present,the research methods of ruminant nutrition are gradually shifted from in vivo studies to in vitro simulation.The dual-flow continuous culture of rumen simulation system is a artificial rumen technology which is close to in vivo fermentation.This experiment uses the newly designed dual-flow continuous culture system,through the stability test,different mesh size effects on fermentation parameters,and nylon bag method test compared with in vitro,to determine the set of dual-flow continuous culture stable period,rumen simulation system operating parameters and a set of sampling period and in vivo fermentation results the closest.Using the same operating parameters,stability test results show that this device is running 9D,and 1~3d to test,4~9d to experiment,the sampling period of 5~7d;this set of equipment in the fermentation process with the number of days to extend the fermentation tank pH increased gradually,basically stable in the range of 6.5~6.6;the number of protozoa in the first 3D die quickly.After gradually stabilized at 1 * 104/mL;number of exhaust and total dry matter disappearance rate had little influence days(P > 0.05);during the whole experiment six fermentation tank with parallel good,strong repeatability.Experiment 2 by using single factor test design of 40 mesh and 30 mesh on the fermentation parameters;results showed that in the test period by 40 mesh sieve aperture change to 30 mesh size,number of days and their interaction on pH,the number of protozoa,exhaust times,total dry matter disappearance rate had no significant effect(P > 0.05);the total volatile fatty acid and ammonia,acetic acid,propionic acid,butyric acid,valeric acid yield no significant effect(P > 0.05);the degradation of dry matter,crude protein,neutral detergent fiber rate had no significant effect(P > 0.05),but the 30 group degradation rate slightly more than 40 mesh group;and organic matter degradation rate in positive test days period will have a significant impact on the(0.01 < p < 0.05),screen aperture and interaction with the number of days the results have no significant effect(P > 0.05).Measuring animal by nylon bag method(0,3,6,12,24,48,72)nutrient h degradation of the seven time points,compared with the part two test results,found consistent parameters for in vitro and in vivo,the rumen 48 h time point closest to the test in vitro.