SGC Bretagne - Expérimenter et évaluer des systèmes de grandes cultures économes en intrants phytosanitaires (de l’intégré au biologique).

Dans le cadre du projet « SGC Bretagne », trois systèmes de culture innovants, sans culture fourragèrepluriannuelle et conçus pour répondre aux besoins des filières d’élevage, ont été conduits durant 6 anset évalués. La conception de ces trois systèmes s’est appuyée sur le cadre « ESR – Efficience,Substitution, Re-conception» : deux systèmes conventionnels s’appuyaient l’un sur la recherched’efficience dans l’utilisation des produits phytosanitaires, l’autre sur les méthodes de reconception dessystèmes de culture ; le troisième était en agriculture biologique. L’évaluation pluri-critères de cessystèmes de culture met en évidence la possibilité de diminuer le recours aux produits phytosanitairestout en maintenant la rentabilité et sans augmenter la charge de travail. Les systèmes de culture testésne pénalisent pas les marges semi-nettes par rapport à la référence utilisée : elles sont équivalentes oumeilleures. La diminution de l’IFT est proche de l’objectif fixé à -50%, avec une réduction de 44% pourles systèmes ayant recours aux produits phytosanitaires, limitée par la dépendance aux herbicides pourla maîtrise des vivaces en interculture. Un autre résultat de l’expérimentation est que la diversificationdes systèmes de culture limite les variations économiques entre années, avec des compensations quise font d’une culture à l’autre au sein de l’assolement

Persistence of fluoroquinolones and ciprofloxacin resistant Enterobacteriacae in soil after poultry manure application

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TEDInternational audienceThis study aimed to evaluate the persistence (i) of two fluoroquinolones, enrofloxacin (ENR) and ciprofloxacin (CIP), and (ii) of CIP-resistant Enterobacteriaceae in soil after poultry manure application. The amounts of ENR and CIP in soil did not significantly change over the 48 day- experimental period. CIP (≤ 30 μg kg-1) was detected in weaker concentrations than ENR (20 to 250 μg kg-1 of soil). The concentration of Enterobacteriaceae (102-103 CFU g-1) did not significantly decrease until Day 36. A total of 145 isolates were identified as belonging to E. coli and to 6 genera. The ciprofloxacin MIC of E. coli reached 32 mg L-1 whereas the other strains of Enterobacteriaceae had a MIC ≤ 0.25 mg L-1. The 71 strains of E. coli were classified in 12 ERIC-PCR genotypes. One genotype, corresponding to a resistant strain, was detected until Day 89. This study showed that enrofloxacin and CIP-resistant E. coli persisted at least 48 and 89 days, respectively, in soil. However, their presence did not increase the MIC of Enterobacteriaceae originating from soil

Persistence of fluoroquinolones and ciprofloxacin resistant Enterobacteriacae in soil after poultry manure application

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TEDInternational audienceThis study aimed to evaluate the persistence (i) of two fluoroquinolones, enrofloxacin (ENR) and ciprofloxacin (CIP), and (ii) of CIP-resistant Enterobacteriaceae in soil after poultry manure application. The amounts of ENR and CIP in soil did not significantly change over the 48 day- experimental period. CIP (≤ 30 μg kg-1) was detected in weaker concentrations than ENR (20 to 250 μg kg-1 of soil). The concentration of Enterobacteriaceae (102-103 CFU g-1) did not significantly decrease until Day 36. A total of 145 isolates were identified as belonging to E. coli and to 6 genera. The ciprofloxacin MIC of E. coli reached 32 mg L-1 whereas the other strains of Enterobacteriaceae had a MIC ≤ 0.25 mg L-1. The 71 strains of E. coli were classified in 12 ERIC-PCR genotypes. One genotype, corresponding to a resistant strain, was detected until Day 89. This study showed that enrofloxacin and CIP-resistant E. coli persisted at least 48 and 89 days, respectively, in soil. However, their presence did not increase the MIC of Enterobacteriaceae originating from soil

Effect of land application of manure from enrofloxacin-treated chickens on ciprofloxacin resistance of Enterobacteriaceae in soil

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TED [Axe_IRSTEA]TED-SAFIRInternational audienceA field plot experiment was carried out to evaluate the impact of spreading chicken manure containing enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP), on the levels of CIP-resistant Enterobacteriaceae in soil. The manures from chickens treated with ENR and from untreated control chickens were applied on six plots. Total and CIP-resistant Enterobacteriaceae were counted on Violet Red Bile Glucose medium containing 0 to 16 mg L-1 of CIP. A total of 145 isolates were genotyped by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The minimum inhibitory concentration (MIC) of CIP for the isolates of each ERIC-PCR profile was determined. The most frequently isolated Enterobacteriaceae included Escherichia coli, and to a lesser extent, Enterobacter and 5 other genera from environmental origin. The composition of the E. coli community differed between manure and manured soil suggesting that the E. coli genotypes determined by ERIC-PCR varied significantly in their ability to survive in soil. One of these genotypes, including both susceptible and resistant isolates, was detected up to 89 days after the manure was applied. Most of the E. coli isolated in soil amended with manure from treated chickens was resistant to CIP (with a MIC ranging between 2 and 32 mg L-1). In contrast, despite the presence of ENR in soil at concentrations ranging from 13-518 microg kg-1, the environmental Enterobacteriaceae isolates had a CIP MI

Effect of land application of manure from enrofloxacin-treated chickens on ciprofloxacin resistance of Enterobacteriaceae in soil

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TED [Axe_IRSTEA]TED-SAFIRInternational audienceA field plot experiment was carried out to evaluate the impact of spreading chicken manure containing enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP), on the levels of CIP-resistant Enterobacteriaceae in soil. The manures from chickens treated with ENR and from untreated control chickens were applied on six plots. Total and CIP-resistant Enterobacteriaceae were counted on Violet Red Bile Glucose medium containing 0 to 16 mg L-1 of CIP. A total of 145 isolates were genotyped by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The minimum inhibitory concentration (MIC) of CIP for the isolates of each ERIC-PCR profile was determined. The most frequently isolated Enterobacteriaceae included Escherichia coli, and to a lesser extent, Enterobacter and 5 other genera from environmental origin. The composition of the E. coli community differed between manure and manured soil suggesting that the E. coli genotypes determined by ERIC-PCR varied significantly in their ability to survive in soil. One of these genotypes, including both susceptible and resistant isolates, was detected up to 89 days after the manure was applied. Most of the E. coli isolated in soil amended with manure from treated chickens was resistant to CIP (with a MIC ranging between 2 and 32 mg L-1). In contrast, despite the presence of ENR in soil at concentrations ranging from 13-518 microg kg-1, the environmental Enterobacteriaceae isolates had a CIP MI

Persistence of fluoroquinolones and ciprofloxacin resistant Enterobacteriacae in soil after poultry manure application

International audienceThis study aimed to evaluate the persistence (i) of two fluoroquinolones, enrofloxacin (ENR) and ciprofloxacin (CIP), and (ii) of CIP-resistant Enterobacteriaceae in soil after poultry manure application. The amounts of ENR and CIP in soil did not significantly change over the 48 day- experimental period. CIP (≤ 30 μg kg-1) was detected in weaker concentrations than ENR (20 to 250 μg kg-1 of soil). The concentration of Enterobacteriaceae (102-103 CFU g-1) did not significantly decrease until Day 36. A total of 145 isolates were identified as belonging to E. coli and to 6 genera. The ciprofloxacin MIC of E. coli reached 32 mg L-1 whereas the other strains of Enterobacteriaceae had a MIC ≤ 0.25 mg L-1. The 71 strains of E. coli were classified in 12 ERIC-PCR genotypes. One genotype, corresponding to a resistant strain, was detected until Day 89. This study showed that enrofloxacin and CIP-resistant E. coli persisted at least 48 and 89 days, respectively, in soil. However, their presence did not increase the MIC of Enterobacteriaceae originating from soil

Effect of land application of manure from enrofloxacin-treated chickens on ciprofloxacin resistance of Enterobacteriaceae in soil

International audienceA field plot experiment was carried out to evaluate the impact of spreading chicken manure containing enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP), on the levels of CIP-resistant Enterobacteriaceae in soil. The manures from chickens treated with ENR and from untreated control chickens were applied on six plots. Total and CIP-resistant Enterobacteriaceae were counted on Violet Red Bile Glucose medium containing 0 to 16 mg L-1 of CIP. A total of 145 isolates were genotyped by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The minimum inhibitory concentration (MIC) of CIP for the isolates of each ERIC-PCR profile was determined. The most frequently isolated Enterobacteriaceae included Escherichia coli, and to a lesser extent, Enterobacter and 5 other genera from environmental origin. The composition of the E. coli community differed between manure and manured soil suggesting that the E. coli genotypes determined by ERIC-PCR varied significantly in their ability to survive in soil. One of these genotypes, including both susceptible and resistant isolates, was detected up to 89 days after the manure was applied. Most of the E. coli isolated in soil amended with manure from treated chickens was resistant to CIP (with a MIC ranging between 2 and 32 mg L-1). In contrast, despite the presence of ENR in soil at concentrations ranging from 13-518 microg kg-1, the environmental Enterobacteriaceae isolates had a CIP MI