AIMS: This study was performed in a well-established in vitro model to investigate whether the application of a glyphosate-containing herbicide might affect the bacterial communities and some biochemical parameters in a cow's rumen. METHODS AND RESULTS: The test item was applied in two concentrations (high and low) for 5 days. In a second trial, fermentation vessels were inoculated with Clostridium sporogenes before the high dose was applied. Effluents were analysed by biochemical, microbiological and genetic methods. A marginal increase in short-chain fatty acid production and a reduction in NH3 -N were observed. There were minor and rather equivocal changes in the composition of ruminal bacteria but no indications of a shift towards a more frequent abundance of pathogenic Clostridia species. Clostridium sporogenes counts declined consistently. CONCLUSIONS: No adverse effects of the herbicide on ruminal metabolism or composition of the bacterial communities could be detected. In particular, there was no evidence of a suspected stimulation of Clostridia growth. SIGNIFICANCE AND IMPACT OF THE STUDY: Antibiotic activity of glyphosate resulting in microbial imbalances has been postulated. In this exploratory study, however, intraruminal application of concentrations reflecting potential exposure of dairy cows or beef cattle did not exhibit significant effects on bacterial communities in a complex in vitro system. The low number of replicates (n = 3/dose) may leave some uncertainty.
AIMS: This study was performed in a well-established in vitro model to investigate whether the application of a glyphosate-containing herbicide might affect the bacterial communities and some biochemical parameters in a cow's rumen. METHODS AND RESULTS: The test item was applied in two concentrations (high and low) for 5 days. In a second trial, fermentation vessels were inoculated with Clostridium sporogenes before the high dose was applied. Effluents were analysed by biochemical, microbiological and genetic methods. A marginal increase in short-chain fatty acid production and a reduction in NH3 -N were observed. There were minor and rather equivocal changes in the composition of ruminal bacteria but no indications of a shift towards a more frequent abundance of pathogenic Clostridia species. Clostridium sporogenes counts declined consistently. CONCLUSIONS: No adverse effects of the herbicide on ruminal metabolism or composition of the bacterial communities could be detected. In particular, there was no evidence of a suspected stimulation of Clostridia growth. SIGNIFICANCE AND IMPACT OF THE STUDY: Antibiotic activity of glyphosate resulting in microbial imbalances has been postulated. In this exploratory study, however, intraruminal application of concentrations reflecting potential exposure of dairy cows or beef cattle did not exhibit significant effects on bacterial communities in a complex in vitro system. The low number of replicates (n = 3/dose) may leave some uncertainty.
Authors: Melissa A Morgan; Corey M Griffith; Meredith M Dinges; Yana A Lyon; Ryan R Julian; Cynthia K Larive Journal: Aquat Toxicol Date: 2019-05-01 Impact factor: 4.964
Authors: Robin Mesnage; Maxime Teixeira; Daniele Mandrioli; Laura Falcioni; Quinten Raymond Ducarmon; Romy Daniëlle Zwittink; Francesca Mazzacuva; Anna Caldwell; John Halket; Caroline Amiel; Jean-Michel Panoff; Fiorella Belpoggi; Michael Nicolas Antoniou Journal: Environ Health Perspect Date: 2021-01-27 Impact factor: 9.031
Authors: Erick V S Motta; Myra Mak; Tyler K De Jong; J Elijah Powell; Angela O'Donnell; Kristin J Suhr; Ian M Riddington; Nancy A Moran Journal: Appl Environ Microbiol Date: 2020-09-01 Impact factor: 4.792