Rainbow trout (Oncorhynchus mykiss, Walbaum 1792) adenocarcinoma investigation with various diagnostic imaging techniques.

Diagnostic imaging techniques provide a new aspect of the ante-mortem and post-mortem diagnostics in fish medicine. Ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) can provide more information about the internal organs and pathognomic lesions. The authors used diagnostic imaging techniques to evaluate and describe the neoplastic malformation in a 3-year-old female rainbow trout (Oncorhynchus mykiss). The fish was examined with Siemens Somatom Definition AS + CT scanner and Siemens Biograph mMR scanner. The animal was lethargic and showed anorectic signs and muscular dystrophy. During the post-mortem investigation, histopathology and immunohistochemistry were also performed allowing us to identify the neoplasms. The results showed a large soft tissue mass in the first mid-intestine segment, which proved to be an adenocarcinoma. This subsequently led to digestion problems and absorption disorders. Immunohistochemically, neoplastic cells of carcinoma revealed E-cadherin and pancytokeratin positivity. This is the first study to report the use of MRI and CT for studying gastrointestinal adenocarcinoma in rainbow trout.

Investigation of the Guinea fowl and domestic fowl hybrids as potential surrogate hosts for avian cryopreservation programmes.

In the last decade, avian gene preservation research has focused on the use of the early precursors of the reproductive cells, the primordial germ cells (PGCs). This is because avian PGCs have a unique migration route through the vascular system which offers easy accessibility. Furthermore, culturing of the cells in vitro, freezing/thawing, reintegration into a recipient embryo and the development of the germ cells can be carried out in well-defined laboratory circumstances. The efficient recovery of the donor genotype and the frequency of germline transmission from the surrogate host animals are still areas which need further development. Thus, the aim of the present study was to investigate an infertile interspecific hybrid (recipient) as an appropriate host for primordial germ cells from native poultry breeds. Guinea fowl × chicken hybrids were produced, the crossing was repeated inversely. The phenotype, the hatching time, the hatching rate, the sex ratio, the presence of own germ cells, the fertility and the phenotype of viable hybrids and the incidence of chromosomal abnormalities of dead hybrid embryos were described. 6.65% viable offspring was obtained with crossing of Guinea fowl females with domestic fowl males. Crossing of domestic fowl hens with Guinea fowl male resulted in lower fertility, 0.14% viable offspring. Based on the investigations, the observed offspring from the successful crossing were sterile male hybrids, thus an extreme form of Haldane's rule was manifested. The sterile hybrid male embryos were tested by injecting fluorescently labeled chicken PGCs. The integration rate of labeled PGCs was measured in 7.5-day, 14.5-day and 18.5-day old embryonic gonads. 50%, 5.3% and 2.4% of the injected hybrid embryos survived and 40%, 5.3% and 2.4% of the examined gonads contained fluorescent labeled donor PGCs. Therefore, these sterile hybrid males may be suitable recipients for male PGCs and possibly for female PGCs although with lower efficiency. This research work shows that the sterility of hybrids can be used in gene conservation to be a universal host for PGCs of different avian species.

Toxic heavy metals in the muscle of roe deer (Capreolus capreolus)--food toxicological significance.

The study was performed on 20 (10 males, 10 females) roe deer (Capreolus capreolus) to investigate the concentration of cadmium, lead, mercury, and arsenic in the muscle tissue. They reside in forest and meadow, about 50 km distance from industrial activities and traffic. Samples were taken from the musculus biceps femoris of each deer without external contamination after shooting during the regular hunting season on a hunting area close to Eger in Hungary. The determination of heavy metal contents was carried out by inductively coupled plasma optical emission spectrometry (ICP-OES). The statistical analysis was performed by statistical package for the social sciences (SPSS) version 11.0. The measured residue concentration of cadmium was below the limit of detection in the roe deer meat indicating no health risk for the consumers. The average lead concentration (0.48 ± 0.21 mg/kg wet weight) exceeded the regulated maximum limit, but its calculated weekly intake was below the provisional tolerable weekly intake (PTWI). The residue level of mercury is not regulated and the average mercury content of roe deer meat (0.87 ± 0.40 mg/kg wet weight) was about half of PTWI, but the consumption of meat with the highest detected concentrations results in higher PTWI than recommended. The measured concentration of arsenic (0.27 ± 0.20 mg/kg wet weight) in the roe deer meat may not pose any health risk for the human consumers according to the PTWI set by the World Health Organization.

Novel mastadenovirus infection and clinical disease in a pygmy marmoset (Callithrix [Cebuella] pygmaea).

We describe the detection and successful isolation of a novel mastadenovirus from a pygmy marmoset (Callithrix [Cebuella] pygmaea) that died following an episode of severe respiratory signs. Pathologic/histopathologic examination revealed hydrothorax and catarrhal bronchopneumonia with pronounced desquamation of the bronchiolar epithelial cells, while in other airways a marked hyperplasia of the epithelial lining and numerous giant cells could be observed. We obtained partial sequence data from the adenoviral DNA-dependent DNA-polymerase gene of the isolated strain and analyses of this region showed the highest level of identity to the recently described bat adenoviruses (strains PPV1 and TJM) and the type 2 canine adenovirus. Similar results were gained by phylogenetic calculations indicating that this novel marmoset adenovirus is only distantly related to reference Old and New World primate adenoviruses and formed a monophyletic group with bat and canine adenoviruses and the equine adenovirus 1. Even though the source of the infection remained unknown, our results could imply the possibility of a cross-species transmission of the virus from an anonymous host to the pygmy marmoset.

Evaluation of mercury and lead content in the liver of the cormorant (Phalacrocorax carbo sinensis) population of Kis-Balaton, Hungary.

Mercury and lead concentrations were measured in the livers of cormorant (Phalacrocorax carbo sinensis), an aquatic bird species living and nesting in the special, highly protected nature conservation area of Kis-Balaton, Hungary. The measurements of metal concentrations were performed by atomic absorption spectrometry using the cold vapour method for mercury and the electrothermal method for lead. Mercury concentrations in the livers were significantly higher in the adult population (4.479 ± 3.336 mg/kg dry matter, DM) than in the juvenile birds (2.682 ± 2.087 mg/kg DM), indicating an increase of bioaccumulation with age. A similar pattern was not observed for lead. There were no statistical differences between males and females either in mercury or in lead concentrations. The average levels of mercury (3.580 ± 2.906 mg/kg DM) and lead (0.746 ± 0.499 mg/kg DM) were statistically different in the liver. No correlation was found between the concentrations of the two heavy metals. Recently, the wild birds have been chronically exposed to subtoxic amounts of metals which have a tendency to accumulate especially in the soft tissues.

Solitary adenoma in the proventriculus of a budgerigar (Melopsittacus undulatus) diagnosed by immunochemistry - short communication.

The authors describe a solitary adenoma in a 5.5-year-old female Budgerigar (Melopsittacus undulatus). The tumour was partially blocking the lumen of the proventriculus and filled it almost completely. Decreased passage of food towards the gizzard and the intestines developed in the bird as result of the obstruction, which periodically hindered the passage, leading to slow emaciation. An epithelial tumour composed of irregular glandular acini was diagnosed by histological examination. Immunohistochemical reaction with pancytokeratin showed a positive cytoplasmic reaction both in the neoplastic and the normal glandular structures.

Claudin-7-positive synchronous spontaneous intrahepatic cholangiocarcinoma, adenocarcinoma and adenomas of the gallbladder in a Bearded dragon (Pogona vitticeps).

In this study, synchronous spontaneous, independent liver and gallbladder tumours were detected in a Bearded dragon (Pogona vitticeps). The multiple tumours consisted of intrahepatic cholangiocarcinoma as well as in situ adenocarcinoma and two adenomas of the gallbladder. The biliary epithelial cells and the cholangiocarcinoma showed membranous cross-immunoreactivity for claudin-7. The gallbladder epithelial cells, its adenoma and adenocarcinoma showed basolateral cross-reactivity for claudin-7. We think that the humanised anti-claudin-7 antibody is a good marker for the detection of different primary cholangiocellular and gallbladder tumours in Bearded dragons. The cholangiocytes, the cholangiocarcinoma, the endothelial cells of the liver and the epithelial cells and gallbladder tumours all showed claudin-5 cross-reactivity. The humanised anti-cytokeratin AE1-AE3 antibody showed cross-reactivity in the biliary epithelial cells, cholangiocarcinoma cells, epithelial cells and tumour cells of the gallbladder. It seems that this humanised antibody is a useful epithelial marker for the different neoplastic lesions of epithelial cells in reptiles. The humanised anti-α-smooth muscle actin (α-SMA) antibody showed intense cross-reactivity in the smooth muscle cells of the hepatic vessels and in the muscle layer of the gallbladder. The portal myofibroblasts, the endothelial cells of the sinusoids and the stromal cells of the cholangiocarcinoma and gallbladder tumours were positive for α-SMA. The antibovine anti-vimentin and humanised anti-Ki-67 antibodies did not show crossreactivity in the different samples from the Bearded dragon.

Development to the blastocyst stage of parthenogenetically activated in vitro matured porcine oocytes after solid surface vitrification (SSV).

The effects of solid surface vitrification (SSV) on viability and parthenogenetic development of in vitro matured (IVM) porcine oocytes was investigated in the present study. Cumulus-free IVM porcine oocytes were subjected either to SSV or SSV combined with a cytochalasin B (CB) pre-treatment (SSV+CB) or all steps of SSV but without cooling (toxicity control=TC; toxicity control with CB pre-treatment=TC+CB). Oocyte viability was evaluated by plasma membrane integrity and esterase activity measured by a combined staining with fluorescein diacetate, propidium iodide and Hoechst 33342. Surviving oocytes were parthenogenetically activated then cultured in vitro (IVC) for 6 days. The proportion of live oocytes after vitrification was significantly lower than that of the TC, TC+CB and the control groups, regardless of the CB pre-treatment. Treatment of oocytes with cryoprotectants did not decrease the rates of surviving oocytes. After activation of oocytes, the proportion of cleaved embryos was significantly higher in the SSV+CB (P<0.05) than that of the SSV group. Nevertheless, significantly more oocytes cleaved (P<0.05) in the TC, TC+CB and the control groups. On Day 6, the rate of blastocysts in the SSV and SSV+CB groups did not differ significantly. The number of oocytes developing to blastocyst and the mean number of blastomeres per embryo were significantly higher (P<0.05) in the TC, TC+CB and the control compared with that of the SSV and SSV+CB groups. To our knowledge, this is the first report on parthenogenetic development to blastocysts of porcine oocytes vitrified at the metaphase-II stage. Results indicate that the high concentrations of cryoprotectants were not harmful for in vitro development, and that CB pre-treatment may increase survival and development of SSV vitrified porcine oocytes.