Multidrug resistance problems targeting piglets and environmental health by Escherichia coli in intensive swine farms

Multidrug resistance(MDR)problems become critical concerns in animal production through food chains and the environment.Thus,the cross-sectional study of E.coli in swine feces,drinking water,and wastewater collected on four medium and four large swine farms in Thailand was studied.The orders of antibiotics used were AMX-COL-GM-TIL and AMX-COL-GM-CER on medium-sized and large swine farms,respectively.Hemolytic E.coli(HEC)was more frequently isolated from all samples than Non-hemolytic E.coli(NHEC).The medium-sized farms were resistant to AMP,AMX,TE,and C,while large farms were resistant to AMP,AMX,TE,and PIP.Only two sensitive antibiotics,namely AK and TE,were available on both farms,whereas,banned NT was still detected in the sludge.The MDR of E.coli isolates was 95.7%and 87.7%on medium-sized and large swine farms,while the highest resistance found was 15 drugs used for NHEC on medium-sized swine farms.The PFGE molecular typing revealed the largest cluster containing five isolations,correlated with drinking water,sow,and fattening isolates;however,the phenotypic and genotypic were not in a similar pattern.The most seriously MDR related to HEC was found in the piglets,effluent,and sludge.Thus,the AMR and MDR of E.coli existence in medium-sized and large swine farms in this study.MDR of E.coli was substantially found in the environmental,including effluent and sludge.Therefore,it inevitably operates the long-term monitoring of AMR,especially targeted piglets and its environment as the main focus of critical antibiotics use in swine farms.

Environmental risk quotient of the antibiotic,phenotypic,and genotypic profiles for antibiotic resistance of Escherichia coli collected from manure and wastewater at swine farms in Prachinburi Province,Thailand

Currently,antimicrobial drug resistance is a problem that deserves thoughtful consideration.Especially in the swine production industry,many pig farms tend to release wastewater into natural water sources,which villagers use for their livelihood.This study aimed to demonstrate the occurrence of phenotypic and genotypic resistance characteristics of E.coli,as well as antibiotic residues in manure and wastewater on swine farms in Prachinburi Province,Thailand.Samples were collected in 2020 and 2021 during the rainy and summer seasons.The results of a questionnaire showed that farmers used antibiotics for disease treatment and prevention at a ratio of 2/4(50%).The most common antibiotic used was amoxicillin(4/4,100%),followed by Enrofloxacin(75%)and colistin(25%).The analysis of antibiotic residue in wastewater by Liquid Chromatography-Mass Spectrometry(LCMS,LC-MS)during the rainy season revealed that amoxicillin(54%)was the highest,followed by florfenicol(14%)and tiamulin(13%).While oxytetracycline(59%),amoxicillin(20%),and florfenicol(11%)were the highest in the summer.The study of Risk Quotient(RQ)indicated that water resources present a risk of antibiotic contamination by sulfonamides,trimethoprim,b-lactam,quinolones,and tetracycline at high levels(SRQ>1)during both seasons.The minimal inhibitory concentrations(MICs)were determined by an antibiotic susceptibility test(AST),analyzed by microdilution technique,and VITEK®2 Compact.The test result indicated that a total of 143 isolates were found in manure(45/143),pre-treatment(51/143),and final effluent(posttreatment,47/143).ESBL-positive resistance was detected at 13%.However,an immensely high percentage of antimicrobial resistance was found for ampicillin(90%),whereas imipenem did not show any drug resistance(0%).The average MIC value towards colistin in all samples was 2.71 mg/ml,while mcr1 was not found in any samples.Furthermore,MDR was expressed in E.coli at as high as 76.22%(109/143).The highest MDR pattern detected was AMP-TETeFFCeSXT.The PCR technique detected that the diversity and abundance of AMR genes were not significantly different from animal manure and wastewater at the swine farms.The bla-TEM was found more frequently than bla-PS.While the tetracycline group(tetA,tetB)and aminoglycoside(aadA1,aadA2,aadB)represented a major proportion,respectively.The PFGE study revealed the possibility of similar genetic morphology from the different isolates found in this study.

Soils and Surface Waters as Affected by Long-Term Swine Slurry Application in Oxisols of Southern Brazil

The accelerated expansion of swine production in Brazil has increased the generation of liquid wastes, which are usually applied to agricultural soils after a simplified treatment and pose potential environmental impacts. The objective of this study was to assess the agronomic and environmental impacts of long-term application of swine slurry(SS) on soil and stream water properties in watersheds dominated by Oxisols in Quinze de Novembro of Southern Brazil. Soil samples(0–30 cm) were collected from farms with continuous application of SS since 1990 at low(40–80 m3 SS ha-1year-1) and high(120–300 m3 SS ha-1year-1) rates of SS. Surface water samples were collected from streams adjacent to the farm fields. Long-term SS application did not change total organic C and particulate organic C compared to cropland and woodland soils without SS application. The high rates of SS increased total N, P, Cu,and Zn and available P and Cu in the topsoil(0–10 cm) compared to woodland and cropland soils without SS application. Surface water analyses showed that fecal coliform bacteria and biological oxygen demand exceeded the legal limits for high quality water(Class 1). Other water parameters(such as NO-3, phosphate and total suspended solids) were within the acceptable limits. Long-term disposal of SS in cropland under no-tillage had impaired water quality in Quinze de Novembro, especially biological parameters. Some best management practices should be adopted, including more rigorous control of SS application to cropland as well as requiring edge-of-field and riparian vegetative buffers.