Hliwa P.,University of Warmia and Mazury |
Dietrich G.J.,Polish Academy of Sciences |
Dietrich M.,Polish Academy of Sciences |
Nynca J.,Polish Academy of Sciences |
And 4 more authors.
Fundamental and Applied Limnology | Year: 2010
The structure of the testes as well as their histology and sperm motility were investigated for whitefish collected during the winter of 2007 from Lakes Lebsko and the Leba River (northern Poland) and Lake Galaduś (northeastern Poland). Two morphologically separated testes lobes, referred to as a cranial (major) and a caudal (minor) lobe, were identified and appeared to be identical to macroscopic structures which have been found in whitefish before. Surprisingly, we found these structures in all fish examined (n = 135 from four samplings). The histological structures of both cranial and caudal parts were described and found to be similar. Spermatozoa collected from both parts could be activated to a similar extent and exhibited similar parameters of swimming speed and trajectory. These results suggest that testes consisting of two separate parts are a normal morphological feature of whitefish testes from these Polish waters. © 2010 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.
Witkowski A.,Wrocław University |
Kotusz J.,Wrocław University |
Wawer K.,Polish Angling Association |
Stefaniak J.,Wrocław University |
And 2 more authors.
Annales Zoologici | Year: 2015
A hybrid Leuciscus leuciscus x Alburnus alburnus was found during the ichthyofaunistic studies in the Bystrzyca River, a left-bank tributary of the Odra River (SW Poland). The hybrid was identified on the basis of its intermediate features and characteristics of the parent species (biometrical, osteological and anatomical) such as opercular and dental bones, pharyngeal bones and teeth, shape of scales, number, form and structure of radial canals of the scales, and air bladder and a complex of meristic and morphometric characters. With respect to its characteristics, the hybrid is closer to dace than to bleak. The small abundance of the hybrid shows that the hybridisation was rather accidental. © Fundacja Natura optima dux.
Urbanska M.,University of Life Sciences in Poznań |
Lakomy A.,Polish Angling Association |
Andrzejewski W.,University of Life Sciences in Poznań |
Mazurkiewicz J.,University of Life Sciences in Poznań
Oceanological and Hydrobiological Studies | Year: 2012
The discovery of a shell of the Chinese pond mussel in 1998 and further confirmation of this species indicate that a reservoir with natural thermal conditions is the oldest species location in Poland. Growth increments of an archival shell do not fall within the ranges obtained by this species in Konin lakes. They are, however, close to population ranges from Hungary. In contrast to other specimens found, the analyzed shell has a very high H/L ratio and is thicker. The observed features might result from the founder effect or they might point to a considerable plasticity of the species. Copyright © of Institute of Oceanography, University of Gdansk, Poland.
Kowalski R.K.,University of Warmia and Mazury |
Hliwa P.,University of Warmia and Mazury |
Cejko B.I.,University of Warmia and Mazury |
Cejko B.I.,Polish Academy of Sciences |
And 3 more authors.
Reproductive Biology | Year: 2012
The effect of Ovaprim (salmon GnRH analogue and a dopamine antagonist) treatment on the quantity and quality of smelt (Osmerus eperlanus L.) sperm was studied in relation to time after hormonal stimulation. Sperm was obtained at 0, 24, 48 and 72 h after treatment (n=13/each time point). Computer Assisted Sperm Analysis (CASA) was used to evaluate sperm motility parameters and histological analysis was used to examine the testis morphology. Only a small volume of semen (1-5 μl) was collected at the beginning of the experiment (time 0) but it dramatically increased 24 h after hormonal treatment. A further increase in semen volume was recorded 48 h after hormonal stimulation. CASA parameters, such as percentage of motile cells, progressive motility, curvilinear velocity, straightlinear velocity, straightness and amplitude of lateral head displacement of stripped sperm increased 48 h after hormonal treatment, which indicates high quality of sperm. No further increase in sperm quality was recorded at 72 h. Compared to stripped semen, testicular semen was characterized by a slightly lower quality. In addition, histological analysis indicated that 24 h after hormonal treatment, a high number of spermatozoa was released from the testis. Ovaprim-stimulated smelt became clearly darker than the control fish. In conclusion, our results suggest that smelt semen should be collected 48 h after hormonal stimulation to ensure high quality of semen. This time may vary depending on maturation status of testis. © 2012 by the Society for Biology of Reproduction.