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Especially in the temperate zone, female bats are exposed to increased energy demands during gestation. In addition, abiotic factors, such as ambient temperature and pathogen load, can significantly affect reproduction success. Bats are considered natural reservoirs for a wide variety of pathogenic agents, and have developed strong immune systems to cope. Nevertheless, very little is known about the influence of these pathogenic microorganisms on bat health as most infections are asymptomatic. In this study, we monitored presence of non-tuberculous mycobacteria (NTM) in female common noctule bats Nyctalus noctula during gestation. Eight NTM species, subspecies or complexes (Risk Group 1: Mycobacterium hiberniae and M. terrae complex; Risk Group 2: M. arupense, M. avium ssp. hominissuis, M. fortuitum, M. interjectum, M. peregrinum, M. septicum) were confirmed as part of the female gut microbiome during gestation, with representation changing during foetal development. Following hibernation, most females were infected, though infection load and severity were relatively low. Just prior to parturition, however, a high proportion of females were infected with a high, often pathogenic, NTM load. Females who gave birth to twins had a higher (though non-significant) proportion of positive samples after hibernation and before parturition. Negative correlations between two consecutive measurements suggest that female N. noctula can cope with NTM loading, even during energy-demanding pregnancies. Bat faeces appear to be a source of numerous NTM species and, as such, bats can be considered as vectors for NTM spread in the environment. [ABSTRACT FROM AUTHOR]

Diclofenac is a drug commonly used in human and veterinary medicine for the treatment of diseases associated with inflammation and pain. Medicinal products enter waste and surface waters on an everyday basis and contaminate the aquatic environment. Fish are therefore permanently exposed to these chemicals dissolved in their aquatic environment. To simulate variable environmental conditions, the aim of our study was to examine adverse effects of diclofenac under different temperatures of cell incubation (18, 21, 24, 27 and 30 °C). Cytotoxic and -static effects of diclofenac in concentrations of 0.001 μg/ml, 0.01 μg/ml, 0.1 μg/ml, 1 μg/ml, 10 μg/ml and 100 μ g/ml f or t he c arp ( Cyprinus carpio) cultured leukocytes were quantified using detection of lactate dehydrogenase released from damaged cells. Overall DCF cytotoxicity was relatively low and its impact was pronounced at higher temperature and DCF concentration. Cells growth inhibition is changing more rapidly but it is high mainly at the highest concentration from low temperature. DNA fragmentation was not detected in tested leukocyte cell line. CYP450 increased diclofenac cytotoxicity only at the highest concentration but at incubation temperatures 18 and 27 °C. Leukocyte viability is essential for immune functions and any change can lead to reduction of resistance against pathogens, mainly in cold year seasons, when the immune system is naturally suppressed. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are carcinogens causing endocrine disruption. While production of PCBs is now banned, wildlife exposure still occurs due to environmental contamination. We investigated thyroid toxicity in wild ungulates using three-dimensional primary thyrocyte cultures exposed to PCB 138 for 24, 48, and 72 h at concentrations ranging within 0--3000 ng/ml. Thyrocyte viability ranged within 78.71--118.34%, 98.14--104.45%, and 84.16--106.70% in fallow deer-, mouflon-, and roe deer-derived cells, respectively. Viability decreased significantly in fallow deer (P = 0.012) and roe deer (P = 0.002) thyrocytes exposed for 48 h at 30 ng/ml. While cytotoxicity ranged within 2.36--16.37%, 3.19--9.85%, and 2.76--11.21% in fallow deer, mouflon, and roe deer, respectively, only roe deer displayed significantly higher cytotoxicity at a 3 ng/ml exposure (P < 0.05) and lower cytotoxicity at 30 ng/ml (P < 0.01). Exposure to 30 ng/ml for 24 and 48 h induced reactive oxygen species in fallow deer. Iodide uptake at 30 ng/ml exposure increased after 24 h in fallow and roe deer, but showed a significant drop after 48 and 72 h in fallow deer, mouflon, and roe deer. Thyroxine T4 release at 30 ng/ml exposure decreased significantly after 48 and 72 h; 24, 48 and 72 h; and 48 h in fallow deer, mouflon, and roe deer, respectively. Our findings indicate time- and species-dependent effects of PCB on performance and thyrocyte function. Use of cell culture models reduces the number of experimental specimens, increases test species welfare and replaces whole organisms with specific target cells. [ABSTRACT FROM AUTHOR]

Bats are presumed primary hosts of trypanosomes of the subgenus Schizotrypanum, including the human pathogen Trypanosoma cruzi. As such, research on bat trypanosomes has been focused on South America, where Chagas disease is a serious issue. While the majority of European studies have been performed in the United Kingdom, there is virtually no data available for Eastern and Central parts of Europe. To address this, the present study aims to identify and assess the prevalence and pathogenicity of trypanosomes in bats sampled in the Czech Republic, Bulgaria, and Poland. Blood collected from 381 adult bats of eight species was tested for presence of trypanosomes using nested polymerase chain reactions. To assess possible impacts of trypanosome parasites on the health status of their hosts, haematological and biochemical analyses were performed for 56 greater mouse-eared bats (Myotis myotis) emerging from hibernacula and 36 females of the same species from summer colonies. The overall prevalence of the two trypanosome species detected (T. dionisii and T. vespertilionis) was 27%, with a significantly higher prevalence in the Czech Republic compared to the other countries studied. Significant differences in bat trypanosome prevalence in different European countries appear to be connected with presence or absence of possible vectors in summer roosts. No impact of trypanosomes on haematology and blood chemistry parameters was detected in Trypanosoma-positive greater mouse-eared bats. Though T. dionisii infection in bats appears asymptomatic, long-term health consequences still need to b studied in greater detail. [ABSTRACT FROM AUTHOR]