Effect Of Animal Manures On Corn Silage Quality And Accumulation And Degradation Of Antibiotics From Animal Manure In Silage

This experiment systematically studied the effects of different kinds of animal manures on the nutritional quality and silage fermentation quality of whole silage corn,and revealed for the first time the transfer of sulfamonomethoxine,oxytetracycline and ofloxacin from soil to the alfafla.We studied the regularity of these three antibiotics’degradaton during the silage fermentation.The specific research contents are as follows:ExperimentⅠ:China is one of the largest animal husbandry countries in the world,which produces a large amount of animal manure every year,so the organic fertilizer resource is extremely rich in China.In order to reuse animal manure,it is particularly necessary to explore the potential to use manure as fertilizer for crop cultivation.Therefore,the current study was conducted to determine the effect of animal manure on nutrients content and fermentation value of corn silage.Randomized complete block design was used in this study,there were four blocks and each block contained 4 treatments.The four treatments were control group(CK)without fertilization,cow manure group(Cow)with 500 g/m~2(dry matter based)cow manure,fowl manure group(Fowl)with 500 g/m~2(dry matter based)fowl manure,and hog manure group(Hog)with 500 g/m~2(dry matter based)hog manure and corn plants were fertilized accordingly.The corn plans were harvested at the 2/3 milk line of the corn kernels and then silage was prepared.The nutrient content of the corn plant and silage(120 days)were measured.Furthermore,fermentation parameters of corn silage were determined.The results showed that application of 500 g/m~2(dry matter based)fowl manure could increase the crude protein and NDF content of whole corn plant,but had no effect on the fermentation quality.Application of 500 g/m~2(dry matter based)hog manure or cow manure did not affect the nutrients content and fermentation quality of silage corn.ExperimentⅡ:A stable and efficient analytical method for the simultaneous determination of 30antibiotics in animal manure was developed and validated.The developed method combines solid phase extraction to enrich and purify sample,and liquid chromatography-tandem mass spectrometry(LC-MS/MS)with multiple reaction monitor model(MRM).The result show that the recovery of tetracyclines,sulfonamides and quinolones are 64.24%~84.43%,60.66%~87.71%and 37.44%~64.58%respectively.The relative standard deviation of all antibiotics less than 20%,and correlation coefficient more than 0.99.Method quantitation limits of tetracyclines and quinolones are 5 ng/g and 0.5~5 ng/g respectively.Method quantitation limits of sulfonamides are 0.1~1 ng/g.The developed method was successfully applied to analyses antibiotics in the swine manure,fowl manure and cow manure.The result show that tetracyclines,sulfonamides and quinolones are all detected in three animal manure,and the tetracyclines were 100%detected in swine manure and fowl manure.The highest concentration of antibiotics is chlortetracycline up to 100.54 mg/kg.ExperimentⅢ:It has been found that antibiotics remaining in soil and sewage can be transferred to vegetables such as radish,celery and tomatoes.However,there are few reports on the transfer of residual antibiotics to earthworms in soils where animal manure is applied.The purpose of this study was to investigate the transfer of sulfamonomethoxine,oxytetracycline and ofloxacin to different parts of sputμm,and to reveal the degradation of antibiotics in silage by silage fermentation.The experiment was designed by random block group and divided into 6 blocks according to the terrain,and each block was processed 10 times.H1,OTC1,OTC2,OFL1,OFL2,SMM1,SMM2 and SMM3 treatment groups were applied dry matter-based pig manure 500 g/m2,and H2 treatment group was applied dry matter-based pig manure 2 kg/m2.150 mg of OTC,1,500 mg of OTC,15 mg of OFL,150 mg of OFL were added to each kilogram of pig manure(dry matter)applied in the OTC1,OTC2,OFL1,OFL2,SMM1,SMM2,and SMM3 treatment groups.5 mg of SMM,50 mg of SMM and 150 mg of SMM,H0is a control group that does not apply fertilizer and does not add antibiotics.The results showed that sulfamonomethoxine was mainly distributed in the root part of earthworm;the distribution of oxytetracycline in different parts of earthworms was related to its concentration in soil,and the concentration of oxytetracycline and ofloxacin in soil and roots and stems And the concentration of oxytetracycline and ofloxacin in leaves was positively correlated;silage fermentation could degrade ofloxacin,but had no effect on oxytetracycline;cows ingested oxytetracycline and ofloxacin by feeding silage The amount of stars is relatively low.In summary,Compare to control group,application of 500 g/m~2 poultry manure increased the crude protein and neutral detergent fiber content of whole plant silage corn,but had no effect on the fermentation quality.The sulfamonomethionine in pig manure is only enriched in the roots of alfalfa,while the oxytetracycline and ofloxacin in pig manure can be transferred to the roots,stems and leaves of alfalfa,and its The concentration is proportional to its concentration in the soil.Silage fermentation can degrade ofloxacin in alfalfa,but has no effect on oxytetracycline.Dairy cows consμme silage and consμme less oxytetracycline and ofloxacin.