Impact of Endocrine Disruptors on Vitellogenin Concentrations in Wild Brown Trout (Salmo trutta trutta)

The adverse effects of endocrine disruptors (EDs) on aquatic wildlife and human health represent a current issue of high public concern. Substantial knowledge of the level of estrogenic EDs in fish has accumulated from field surveys. For this purpose, a survey of wild brown trout (Salmo trutta trutta) was carried out to assess the incidence of EDs in the feral fish population living in the Liri river (Abruzzi, Italy). The results of this study show that this aquatic environment possesses an estrogenic potency that triggered the increase of vitellogenin levels in both female and male trouts. Fish exposed to different pesticides and urban waste in downstream river showed higher vitellogenin levels in comparison to the headwater site. Furthermore, some trouts coming from the downstream reported the presence of several pesticides and fungicides, some of these banned several years ago.

Toxicological, gene expression and histopathological evaluations of environmentally realistic concentrations of polybrominated diphenyl ethers PBDE- 47, PBDE-99 and PBDE-209 on zebrafish embryos

Polybrominated diphenyl ethers (PBDEs) are brominated flame retardants. Biomonitoring studies have shown widespread presence of PBDEs in humans and their accumulation in food chain cause concern to human health, especially for foetus and infant development. The early-life stages are generally considered more sensitive to exposure to toxic compounds than juvenile or adults. For this reason the aim of this study was to evaluate the effects of the three most environmentally relevant BDE (BDE- 47, 99 and 209) on zebrafish embryos. The fish embryo toxicity (FET) OECD tests on zebrafish were performed followed by histopathogical examination to assess morphological changes. The gene expression of the thyroid stimulating hormone β (Tshβ), the transport proteins transthyretin (Ttr) and thyroxine-binding globulin (Tbg) as well as the enzyme iodothyronine deiodinase 1 (Dio1) was also assessed by Real-time PCR. BDE-47 and BDE-99 showed an increase of the severity of the effects at the lower concentrations while for the BDE-209 the effects were higher to the high concentrations. Although all compounds did not show any acute toxicity for none of the concentrations tested, they reported interesting sub-acute lesions, including yolk and pericardial edema, tail and head malformation, reduced and extremely reduced heart beat rate, blood stasis and spinal curvature, with the highest percentage recorded for BDE-209. Cardiac edema, damage of eye structure and hydrocephaly were confirmed also by histophatological examination. Furthermore, a toxic and dose-dependent liver vacuolization in BDE-209 was observed in all experimental groups. Although no statistically significant difference in gene expression was observed, BDE-209 up-regulated only Dio1 while the other congeners induced Tshβ, Ttr, Tbg and Dio1. Overall, this research highlighted that exposure to BDE-47, BDE-99 and BDE-209 at realistic concentrations caused lethal and sub-lethal alterations and impaired genes involved in thyroid hormones homeostasis leading to abnormal development of zebrafish embryos.

Occurrence of agrochemical residues in beeswax samples collected in Italy during 2013-2015

Considering the importance of honey bees for pollination activity and biodiversity preservation different studies have dealt with the impact of pesticides on honeybee health. Within the hive, beeswax is a matrix of particular interest because most of the chemicals used in agricultural and beekeeping activities can easily accumulate and persist in this matrix long after treatment has ceased, affecting honeybees survival. However, chemical analyses of pesticide residues in beeswax are not mandatory, so there are no residue limits, for beeswax. The present study was carried out with the aim of investigating the beeswax residue pattern in the Italian hives. 178 beeswax samples collected from 2013 to 2015 were analyzed for 247 pesticides. 73.6% of the analyzed samples reported the presence of one or more pesticides. On average every single sample showed a mean of three different pesticides each with a maximum of fourteen compounds, some of which were banned in Europe or not authorized in Italy. The higher frequencies were associated with three acaricides: coumaphos (60.7% of samples), tau-fluvalinate (50%) and chlorphenvinphos (35.4%), but the higher concentrations were associated to pyrethrins and piperonil butoxide.

Pharmacokinetics of marbofloxacin administered via intravenous regional limb perfusion in dairy cows: evaluation of two different tourniquets

Objectives

This study evaluated synovial and systemic plasma pharmacokinetic variables of marbofloxacin after a single intravenous regional limb perfusion (IVRLP) performed using two different tourniquets in clinically healthy, standing, non-sedated dairy cows. The authors hypothesised that the type of tourniquet used for IVRLP would influence the synovial fluid concentration of marbofloxacin in the perfused distal limb.

Design

The study had a randomised parallel-group design.

Methods

Ten adult dairy cows were included. Unilateral hindlimb IVRLP through the dorsal common digital III vein was performed in two groups of five cows (group 1: wide rubber tourniquet; group 2: manual pneumatic tourniquet) using 0.67 mg/kg of marbofloxacin. The tourniquet was applied proximal to the tarsus and maintained for 30 minutes. Samples of jugular blood and synovial fluid from the tibiotarsal joints of the perfused limb were obtained before and at intervals after IVRLP. All samples were analysed for drug concentrations using liquid chromatography tandem mass spectrometry. Pharmacokinetic parameters were determined to establish the influence of tourniquet types. Differences were considered significant at P≤0.05.

Results

No adverse effects from the procedure or marbofloxacin were observed in any animal. Significant differences in synovial concentrations and pharmacokinetic parameters were measured. The mean ± sd areas under the concentration versus time curve from time 0 to 24 hours were 178.98±58.08 µg hour/ml for group 2 and 21.11±9.93 µg hour/ml for group 1. The mean ± sd maximum marbofloxacin concentrations were 75.50±10.19 µg/ml for group 2 and 6.35±1.47 µg/ml for group 1.

Conclusions

Performing IVRLP using the dorsal common digital III vein and a manual pneumatic tourniquet set at 300 mmHg above the tarsus in standing cows resulted in significantly higher marbofloxacin concentrations in the tibiotarsal joint compared with those with the wide rubber tourniquet.

Trial registration

Local ethical committee (number 41/2012/CEISA).

Effect of cooking on total mercury content in Norway lobster and European hake and public health impact

The risk of Hg poisoning by eating seafood is considered real from the several international agencies that recommended, by fish consumption advisories, to pregnant women and young children to avoid or severely limit the consumption of the fish and shellfish with a high-range mercury levels. The analyses of two common species, European hake and Norway lobster, collected from an area of Central Adriatic Sea, reported high mercury levels in crustaceans. For Norway lobster total mercury exceeded, in six out of ten analysed pools, the recommended 0.5mg/kg wet weight European limit. Moreover the increased amount of Hg concentrations in Norway lobster cooked samples suggests the necessity to review current procedures of Hg control in food, considering also consumption habits of consumers. The Hg values found in all European hake samples are below the legal limits and, in this species, the boiling did not modify the concentrations in fish tissues.

Confirmation of crayfish plague in Italy: detection of Aphanomyces astaci in white clawed crayfish

In the summer of 2009, high levels of mortality among white clawed crayfish Austropotamobius pallipes were observed in 3 watercourses of central Italy. PCR and culture methods were used to detect the causative agent of the disease. Two strains of Aphanomyces spp. were isolated and identified by PCR and DNA sequencing as Aphanomyces astaci and A. repetans. This is the first crayfish plague outbreak in Italy to be confirmed by the isolation in culture of a pathogen from Austropotamobius pallipes.

Vaccination trials of sea bass (Dicentrarchus labrax) against pasteurellosis using oral, intraperitoneal and immersion methods

Photobacterium damsela subsp. piscicida (Phdp) is the aetiological agent of fish pasteurellosis, causing heavy losses in intensive mariculture plants. The present work compares the protective efficacy of five different vaccine formulation: oral, intraperitoneal, immersion, bivalent immersion (Vibrio anguillarum) and immersion associated with immunostimulants. Each of these vaccine formulations containing whole cells of Phdp formalin inactivated (FKC), was administered to 100 sea bass weighing approximately 2 g; 100 non-vaccinated sea bass were used as controls. Protection against pasteurellosis was tested for 40 days after vaccination by intraperitoneal challenge: each fish was inoculated with Phdp cells at a concentration of 2.75 x 10(4) cfu/ml. Mortality was recorded over the following 14 days, vaccine protection was evaluated using a relative percentage survival (RPS) index. The intraperitoneal formulation gave excellent protection (RPS 82.4%). The most effective immersion form was that followed by simple immersion (RPS 23.1%) followed by the group vaccinated with bivalent vaccine (RPS 18.7%). Protection conferred orally (RPS 28.6%) is of interest for practical purposes.