Course "Fluorescence microscopy - FluoMicro@ICGEB"

Ilija participated at the Course "Fluorescence microscopy - FluoMicro@ICGEB" organized by International Centre for Genetic Engineering and Biotechnology - ICGEB in Trieste, Italy, in the period 2-4 October 2018. During the course, following topics we covered:
  • Confocal Imaging
  • High-throughput imaging
  • Time-lapse microscopy
  • Image processing and quantitative analysis


New paper in Theriogenology

A new paper in collaboration with our colleagues from Kaposvár University (Hungary) has been accepted for publication in Theriogenology.

Müller T., Szabó T., Kollár T., Csorbai B., Marinović Z., Horváth L., Kucska B., Bodnár Á., Urbányi B., Horváth Á. 2018. Artificial insemination of African catfish (Clarias gariepinus) using cryopreserved sperm. Theriogenology. In press. DOI: 10.1016/j.theriogenology.2018.09.034

 A B S T R A C T
In this study, we aimed to develop a practical protocol for using cryopreserved sperm for induced/wild/tank spawning of fish species with external fertilization. Experiments were carried out on African catfish (Clarias gariepinus) as a model species. Sperm was collected for cryopreservation and diluted with the cryomedium (266mM fructose, 20% methanol) at a ratio of 1:1 with a final methanol concentration of 2.47M pH7.73. Diluted sperm was loaded into 0.5-ml straws and cryopreserved by conventional protocol. Samples were prepared for insemination 24 h later, by thawing for 13 s in a 40°C water bath, and centrifuged at 500×g for 10minat 20°C. The seminal plasma, extender and external cryoprotectant were removed from the concentrated spermatozoa. The pellet was then resuspended in common carp (Cyprinus carpio) seminal plasma to reconstitute the lost volume. Sperm samples were then injected by a catheter into the ovarian cavity through the oviduct of the experimental females by the so-called ovarian lavage method in parallel with the intramuscular hormonal administration (5mg carp pituitary/kg bw). Inseminated females (n=9) were monitored for 10h and ovulated eggs and spermatozoa stored in in the ovary were stripped. Stripped gamete samples were divided into two batches: (1) the first batch contained only the previously injected spermatozoa and was activated by aerated water (WA) immediately after stripping; (2) in case of the second batch additional, freshly stripped sperm was added as positive control to the stripped eggs before water activation (PC). Furthermore, five females were propagated by using the dry fertilization method (in vitro fertilization) as negative control (NC). All sperm and hormone injected females produced fertilised eggs with a hatching rate of 17.7±13.2%, 12.5±9.3%, and 61±11.5% for WA, PC and NC respectively. These results indicate that artificial insemination based on using cryopreserved sperm with ovarian lavage can be a viable alternative to in vitro fertilization in a catfish species. Thus, we describe a proof of principle for a practical protocol for the induced/wild/tank spawning of an externally fertilising fish species with economical importance and propose that the protocol could be also applied to endangered marine or fresh fish species.


The second meeting of biologists in Serbia

Jelena, Ilija and Zoran have participated at The second meeting of biologists in Serbia organized in Kladovo, Serbia (25th – 30th September). During the meeting, they gave two oral and two poster presentations of papers done in collaboration with our colleagues from Japan, Slovenia and Serbia.

Lujić J., Marinović Z., Sušnik Bajec S., Kása E., Urbányi B., Horváth Á. 2018. Cryopreservation and transplantation of germ cells as a method for ichthyofauna conservation. [in Serbian]. Abstract book. The second Congress of Biologist in Serbia; 25-30 Sepember, 2018, Kladovo, Serbia.pp.92.

Šćekić I., Marinović Z., Lujić J., Kása E., Kollár T., Urbányi B., Horváth Á. 2018. Identification of sperm subpopulations of carp sperm [in Serbian]. Abstract book. The second Congress of Biologist in Serbia; 25-30 Sepember, 2018, Kladovo, Serbia.pp.292.

Marinović Z., Lujić J., Yoshizaki G., Li Q., Garai E., Csenki Zs., Urbányi B., Horváth Á. 2018. Conservation of different zebrafish lines by spermatogonia transplantation. [in Serbian]. Abstract book. The second Congress of Biologist in Serbia; 25-30 Sepember, 2018, Kladovo, Serbia.pp.315.

Marinović Z., Kostić D., Marković G., Bolić-Trivunović V., Miljanović B., Lujić J. 2018. Growth of gibel carp Carassius gibelio (Bloch, 1782): adventages of multimodel inference. [in Serbian]. Abstract book. The second Congress of Biologist in Serbia; 25-30 Sepember, 2018, Kladovo, Serbia. pp.120.    
Biologists and friends
Ilija presenting
Poster session
Chairman and chairwoman :)
Jelena presenting
Beautiful Kladovo
Danube in the National park Djerdap


New paper in Toxicon

New paper in collaboration with our colleagues from University of Novi Sad (Serbia) has been accepted for publication in Toxicon. It is the fourth paper that came out from our collaboration and we are looking forward to the next.

Eighty cultures from the Novi Sad Cyanobacterial Culture Collection (NSCCC) were screened for toxicity with Artemia salina bioassay and for common cyanobacterial toxins, microcystins/nodularin (MCs/NOD) and saxitoxin (STX), with ELISA assays. The results show that 22.5% (11) of the investigated cyanobacterial cultures in exponential phase exhibited toxicity in the A. salina bioassay and 38.7% (31) produced MCs/NOD and/or STX. However, the findings in the two methods applied were contradictory. Therefore, A. salina bioassay was repeated on 28 cultures in stationary growth phase, which were positive in ELISA assays but not in the initial A. salina bioassay. Seven more cultures exhibited cell-bound toxicity, and only one extracellular toxicity. The observed difference in the toxicity indicates that cyanobacterial growth phase could affect the screening results. The findings also varied depending on the environment from which the cultures originated. In the initial screening via bioassay, 11.8% (6 cultures out of 51) from terrestrial and 17.2% (5 out of 29) from aquatic environment showed cell-bound toxicity. Furthermore, based on the ELISA assay, 31.4% (16) of the cultures from terrestrial ecosystems were positive for the presence of the investigated cyanotoxins, and 51.7% (15) from aquatic ecosystems. Based on all results, more frequent toxin production was observed in cultures originating from aquatic environments. Furthermore, the group of terrestrial cultures that originated from biological loess crusts were basically non-toxic.
The discrepancies in the results by two different methods indicates that the use of several complementary
methods would help to improve the assessment of cyanobacterial toxicity and cyanotoxin analyses.