Evaluation of eco-toxicological effects of the parasiticide moxidectin in comparison to ivermectin in 11 species of dung flies

A standardized bioassay previously developed with ivermectin for the yellow dung fly (Scathophagidae) and the face fly (Muscidae) was applied to test the response of 11 dung fly species to the presumably less toxic parasiticide moxidectin. The results were compared to existing data for the same species tested with ivermectin, albeit two new species (Scathophaga suilla and Musca domestica) were tested here with both the substances. Estimated lethal effect concentrations LC50 at which 50% of the flies died ranged more than tenfold from 0.012 mg moxidectin/kg fresh dung for Sepsis neocynipsea (Sepsidae) to 0.140 mg moxidectin/kg fresh dung for the house fly Musca domestica (Muscidae). In most of the species, we additionally revealed sub-lethal effects at lower moxidectin concentrations in terms of retarded growth and development and reduced body size. Mortality thresholds were about ten times higher for moxidectin than for ivermectin, hence moxidectin is indeed less toxic than ivermectin in absolute terms. Crucially, we obtained strong correlations among the 11 tested fly species in both lethal and sub-lethal responses to the two substances, such that species relatively sensitive to ivermectin were also relatively sensitive to moxidectin. Such correlations are expected if the two substances are structurally related and function in the same manner by disturbing ion channel transport. Methodologically speaking, all species used proved suitable for toxicological testing of parasiticides

Draft Genome of Streptomyces zinciresistens K42, a Novel Metal-Resistant Species Isolated from Copper-Zinc Mine Tailings

A draft genome sequence of Streptomyces zinciresistens K42, a novel Streptomyces species displaying a high level of resistance to zinc and cadmium, is presented here. The genome contains a large number of genes encoding proteins predicted to be involved in conferring metal resistance. Many of these genes appear to have been acquired through horizontal gene transfer

Environmental risk assessment of ivermectin – A case study

Liebig M, Fernandez A, Blübaum-Gronau E, et al. Environmental risk assessment of ivermectin – A case study. Integrated Environmental Assessment and Mangagement. 2010;6(S1):567-587