OBJECTIVES: Here we tested the hypothesis that multiple toxic and infectious stressors combine in their adverse effects to produce higher tissue responses of metallothioneins (MTs) in birds. METHODS: We used Japanese quails as a model avian species. The study is based on data obtained from single and combined exposures of Japanese quails to cyanobacterial biomass containing microcystins, lead and a live Newcastle disease vaccination virus. Eight groups of 5 birds were exposed to single, double and triple combinations of these stressors and compared with controls. Birds were euthanized after the 30-day exposure to collect brain, liver, kidney, and pectoral muscle for MTs measurement. RESULTS: Baseline levels of MTs differed in avian tissues. The gradient of MTs in control quails was pectoral muscle < liver < brain < kidney. Double and triple exposures induced higher levels of MTs. While increases of MTs were driven mainly by dietary exposure to cyanobacterial biomass and/or lead, Newcastle disease vaccination induced the least response. Induction of brain MTs was dominated by exposure to lead. Patterns of MTs responses were similar in the liver and pectoral muscle as well as in the kidney and brain. CONCLUSIONS: Understanding better responses of birds to oxidative stress induced by toxic and infectious stressors may have implications for avian conservation issues and disease risk assessment.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: While commercial poultry and captive birds are exposed to antimicrobials through direct medication, environmental pollution may result in contamination of wild birds. Fluoroquinolones are commonly used medications to treat severe avian bacterial infections; however, their adverse effects on birds remain understudied. Here, we examine toxicity of enrofloxacin and marbofloxacin during the egg incubation period using the chicken (Gallus Gallus domesticus) as a model avian species. Laboratory tests were based on eggs injected with 1, 10 and 100 μg of fluoroquinolones per 1 g of egg weight prior to the start of incubation and monitoring of chick blood biochemistry, reproductive parameters and heart rate during incubation. RESULTS: Eggs treated with fluoroquinolones displayed reduced hatchability due to embryonic mortality, particularly on day 13 of incubation. Total hatching success showed a similar pattern, with a significantly reduced hatchability in low and high exposure groups treated with both enrofloxacin and marbofloxacin. From 15 to 67% of chicks hatching in these groups exhibited joint deformities. Hatching one-day pre-term occurred with a prevalence of 31 to 70% in all groups treated with fluoroquinolones. Embryonic heart rate, measured on days 13 and 19 of incubation, increased in all enrofloxacin-treated groups and medium and high dose groups of marbofloxacin-treated eggs. Blood biochemistry of chicks sampled at hatch from medium dose groups showed hypoproteinaemia, decreased uric acid and increased triglycerides. Chicks from the enrofloxacin-treated group displayed mild hyperglycaemia and a two-fold rise in the blood urea nitrogen to uric acid ratio. Principal components analysis based on blood biochemistry clearly separated the control bird cluster from both enrofloxacin- and marbofloxacin-treated birds. CONCLUSIONS: Fluoroquinolones induce complex adverse effects on avian embryonic development, considerably reducing the performance of incubated eggs and hatching chicks. Cardiotoxicity, which quickens embryonic heart rate, meant that the total number of heart beats required for embryogenesis was achieved earlier than in the standard incubation period, resulting in pre-term hatching. Our data suggest that enrofloxacin has a higher potential for adverse effects than marbofloxacin. To conclude, care should be taken to prevent exposure of reproducing birds and their eggs to fluoroquinolones.
- MeSH
- antiinfekční látky toxicita MeSH
- enrofloxacin toxicita MeSH
- fluorochinolony toxicita MeSH
- hypoproteinemie chemicky indukované veterinární MeSH
- kur domácí * krev MeSH
- kuřecí embryo účinky léků MeSH
- nemoci drůbeže chemicky indukované MeSH
- rozmnožování účinky léků MeSH
- srdeční frekvence účinky léků MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo účinky léků MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: Chemical restraint of wild animals is practiced to accomplish intended procedures such as capture, clinical examination, collection of diagnostic samples, treatment and/or transport. Extra-label use of animal medicinal drugs is often necessary in wildlife because most approved therapeutics do not list wild species on the labelling. Here, we used cellular in vitro models, a cutting-edge tool of biomedical research, to examine cytotoxicity of anaesthetic agents in fallow deer and extrapolate these data for anaesthetic risks in wildlife. METHODS: We examined the cytotoxic effects of ketamine, xylazine, and ketamine-xylazine, i.e. the Hellabrunn mixture, on liver-, heart- and kidney-derived cell cultures prepared from a fallow deer (Dama dama) specimen. In line with preliminary studies we exposed cells to 10 µM, 50 µM, 100 µM, 1 mM, and 10 mM ketamine or xylazine. The combination of ketamine-xylazine was dosed at 0.025+0.02 mg/ml, 0.05+0.04 mg/ml, 0.75+0.06 mg/ml, 0.1+0.08 mg/ml, and 0.125+0.1 mg/ml per one well containing 10 000 cells. The quantification of cytotoxicity was based on lactate dehydrogenase activity released from damaged cells. RESULTS: Liver-derived cells show higher sensitivity to the cytotoxic effects of both ketamine and xylazine administered as single drugs when compared with cells cultured from the heart and kidney. The Hellabrunn mixture induced significantly higher cytotoxicity for kidney-derived cells ranging from 16.78% to 35.6%. Single and combined exposures to ketamine and xylazine resulted only in high-dose cytotoxicity in the heart-derived cells. CONCLUSIONS: Our results indicate that immobilization drugs significantly differ in their cytotoxic effects on cells derived from various organs of the fallow deer.
- MeSH
- analgetika toxicita MeSH
- cytotoxiny toxicita MeSH
- játra cytologie metabolismus MeSH
- ketamin analogy a deriváty toxicita MeSH
- ledviny cytologie metabolismus MeSH
- srdce účinky léků MeSH
- testy toxicity metody MeSH
- vysoká zvěř * MeSH
- xylazin analogy a deriváty toxicita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
