Study On Application Of Fermented Cassava Residues In Huanjiang Mini-pigs Production

In this paper,three kinds of microbial starters(A:Bacillus≥2.00×10~9cfu/g+Lactobacillus≥3×10~9 cfu/g+Saccharomyces cerevisiae 5×10~9 cfu/g),B:Pediococcus pentosaceus 6×10~8 cfu/g+Saccharomyces cerevisiae≥4×10~9 cfu/g,C:Lactobacillus plantarum 1×10~8 cfu/g+Bacillus subtilis 0.2×10~8cfu/g+Saccharomyces cerevisiae 0.2×10~8 cfu/g)were mixed with fresh cassava dregs in a ratio of 1:1000,and the change of conventional nutrients after fermentation at different time was measured,so as to screen out microbial starters with good fermentation effect and fermentation time;the selected microbial starters was used to ferment cassava residues;and then the growth performance,plasma biochemical parameters and amino acids,carcass quality,and meat quality of Huanjiang mini-pigs were determined after dietary supplementation with the cassava residues(CR)or fermented cassava residues(FCR),to provide a theoretical basis for the resource utilization of CR in Huanjiang.The main results are the following:1.The crude protein content of FCR in fermentation group C increased(P<0.05)by 73.03%on day 14 of fermentation compared with that before fermentation.The neutral detergent fiber content of FCR in fermentation groups A,B,and C decreased(P<0.05)by 23.13%(Day 3),28.61%(Day 56),and 13.44%(Day 28);the crude fat content increased(P<0.05)by 28.89%(Day 28),10.38%(Day 56),and 45.84%(Day 14);the crude ash content increased(P<0.05)by 16.27%,8.26%,and 0.85%on day 56 of fermentation,respectively.The total energy level of FCR in fermentation groups B and C reached the maximum.2.In Stage 1,compared with the control group,the average backfat thickness,average daily feed intake,and slaughter rate decreased(P<0.05);skin rate increased(P<0.05);muscle brightness value decreased;redness value increased(P<0.05);and muscle My HC-Ⅱx expression increased(P<0.05);the heart index of the FCR group increased(P<0.05);there were no significant changes in other indicators.In Stage 2,the live body weight,carcass weight,and muscle redness increased(P<0.05)in the FCR group;the average daily feed intake and cooked meat rate increased(P<0.05)in the CR group and FCR group;there were no significant changes(P>0.05)in other indicators.3.In stage 1,the serum concentrations of low-density lipoprotein-cholesterol and arginine increased(P<0.05)in the CR group,serum concentrations of total cholesterol and low-density lipoprotein-cholesterol increased significantly(P<0.05),while cholinesterase activity and concentrations of aspartate,proline,and phenylalanine decreased(P<0.05)in the FCR group.Compared with the CR group,serum cholinesterase activity and concentrations of arginine,aspartate,glutamate,and lysine were reduced(P<0.05)in the FCR group.In stage 2,the serum phosphorus concentration increased(P<0.05)and concentrations of tryptophan and proline decreased(P<0.05)in the FCR group.Compared with the CR group,serum concentrations of total cholesterol,phosphorus,low-density lipoprotein-cholesterol,and valine were increased(P<0.05)while threonine concentration was decreased(P<0.05)in the FCR group;there were no significant changes(P>0.05)in other indicators.Conclusions:Microbial fermentation agents can effectively improve the nutritional value of cassava residues.The fermentation value of fermentation agent C for 14 days has the most obvious increase in the nutritional value,especially crude protein and crude fat content.It can be used for short-term fermentation of cassava residues.Dietary supplementing 5-10%FCR can improve the growth performance,organ index,carcass traits,and meat quality of Huanjiang mini-pigs.Long-term feeding does not affect their nutrient metabolism.