No abstract

Sturgeon aquaculture production has increased worldwide, particularly in Italy, yet there is little information about diseases that affect sturgeons. With this study we describe the results of screening for bacterial infections during monitoring campaigns carried out from 2014 to 2017. A total of 402 sturgeons from six sturgeon farms with one or more reared sturgeon species among five species and two hybrids were analysed. Bacteriological exam was positive in 93 individuals (23%) and negative in the remaining 309 (77%). Generally, no external or internal macroscopic lesions were present, though some specimens showed skin lesions, liver anaemia or splenomegaly, which are non‐pathognomonic signs of bacterial infection. The majority of the isolated bacteria were opportunistic. This knowledge base is important to help create a bacterial profile of sturgeons reared in Italy.

Perfluoroalkylated substances (PFASs) are highly fluorinated aliphatic compounds with high thermal and chemical stability, used in a range of industrial applications. Extensive screening analyses in biota samples from all over the world have shown the bioaccumulation of PFAS into higher trophic levels in the food chain. Perfluorooctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. Ingestion of fish and other seafood is considered the main source of exposure of these contaminants. Here, we quantified PFOS and PFOA by LC-MS/MS in muscle samples of European perch from Lake Varese, Italy. PFOS was detected in all samples with concentrations of up to 17.2 ng g(-1). Although the reported values were lower than the recommended total daily intake (TDI) proposed by the European Food Safety Authority (EFSA), fish from Lake Varese may be a significant source of dietary PFOS exposure.

No abstract

Currently, land abandonment constitutes a serious threat for many species tied to semi-natural grasslands. In southern Europe, the conservation of many grassland bird communities largely depends on low-intensity mountain farming. In this study, we analysed the effects of the main farming practices promoting grassland maintenance, i.e. grazing and mowing, on species richness of a Prealpine grassland bird community and on the breeding densities of the two commonest grassland species, the skylark (Alauda arvensis Linnaeus, 1758) and the tree pipit (Anthus trivialis Linnaeus, 1758). The two study sites were located between 1100 and 2000 m above sea level in the Italian central Prealps. Grassland species richness was positively affected by grazing, and increased with increasing distance from the nearest woodland. Skylark density was positively influenced by mowing, grassland cover extent and distance from woodland, with the latter effect occurring only at a single study site. Finally, tree pipit density was positively affected by grazing. Our findings suggest that, in order to maintain open grasslands below the natural treeline and enhance the biodiversity of grassland bird communities, grazing should be preferred over mowing. Moreover, woodland edge effects may have a negative impact on mountain grassland bird communities. Advancing woodlands and abandonment of low-intensity farming and grazing practices may therefore constitute a serious threat for open-habitat specialist bird species of the Alpine region.