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Odběr spermatu pomocí katetru a jeho využití při výtěru štiky obecné (Esox lucius L.)
PLAŇANSKÝ, Tomáš
The aim of this diploma thesis is to compare quality of northern pike sperm collected by different methods. First method is collection of stripped sperm by abdominal massage of the belly. Second method is collection of stripped sperm with special catheter to eliminate sperm contamination by urine. The last method is collection of testicular sperm. Differently collected sperm was evaluated and compared its quality. The main observed parameters were sperm volume, spermatozoa concentration, spermatozoa motility and velocity and osmolality of seminal fluid. Sperm samples were used for eggs fertilization. In fertilized eggs, the fertility of eggs and larvae hatching rate were observed.
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Hormonal stimulation of ovulation of grass carp (Ctenopharyngodon idella)
MUSIL, Martin
Hormonal stimulation of ovulation in grass carp (Ctenopharyngodon idella) In 2015, an experiment with hormonal stimulation of ovulation in grass carpwas performed using dopamine inhibition of secretion luteinizing hormone (LH) by mGnRHa ([D-Tle6, Pro9, NEt] -mGnRH), with or without metoclopramide. Three experimental groups of females were injected with the following hormonal preparations: group A - mGnRHa (12.5 mikrog.kg-1) + metoclopramide (20 mg.kg-1), group B - mGnRHa (12.5 mikrog.kg- 1) Group C - 0.9% NaCl. For group A injected mGnRHa with metoclopramide, ovulation only achieved one of the females (14.28%), the fecundity index was 5.66% and the fertility was only 0.1%. The luteinizing hormone concentration peaked after application of the hormonal preparation and, unlike group B, declined with imminent ovulation. In Group B, the application of pure synthetic mGnRH induced ovulation in 57.14% of injected females. Fecundity index was 11.25 +- 4.77% and average fertility reached 60.25 +- 11.22%. The level of luteinizing hormone reached its peak only at the time just before ovulation itself. The results of the experiment did not demonstrate the use of mGnRHa with metoclopramide as the most effective. However, LH levels have shown a strong dopamine inhibition of LH secretion in this species.
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The Short-Term Storage of Unfertilized Roe of the African Catfish (Clarias gariepinus).
FLOKOVIČ, Michal
The Short-Term Storage of Unfertilized Roe of the African Catfish (Clarias gariepinus). For my Bachelor's Thesis, I address the issue of preserving and incubating the roe of the African Catfish (Clarias gariepinus). This species can be bred very well at high stock concentrations in recirculation systems. The optimal breeding temperature is 25-28°C. Pellets with a concentration of over 40% protein are used as food. The advantages are very rapid growth and high-quality lean meat with a small amount of bones. This species is bred in the Czech Republic on a very limited basis, the reason for this is a conservative approach of both fish breeders and customers. The intensive breeding of the African Catfish is developed mostly in Holland and Hungary, and it is extensively produced in ponds and in certain African countries such as Egypt, Nigeria, Ghana, etc. Reproduction is usually carried out by artificial smearing using hormone-induced ovulation. The possibility of preserving unfertilized roe is known at certain other species of fish bred in aquaculture systems, as there is an effect of water on the unfertilized roe. There is no information available in literature in this respect concerning the African Catfish. There were two objectives of the experiments I carried out. The first objective was to ascertain the possibility of preserving the roe at various temperatures before insemination. The second objective was to ascertain the influence of the contact duration of the uninseminated roe with water on their ability to fertilize. In both cases, the percentage of fertilized roe and the percentage of hatched larvae from the seeded roe were valuable parameters. The roe originated from an artificial smear using a hormonal stimulation of female fish with the Hungarian product Ovopel. The product contains a synthetic analogue releasing hormone luteinizing hormone and a dopaminergic inhibitor supplement. It is used for the artificial propagation of other species of fish in addition to the African Catfish. The experiments began in June 2010 and continued until March 2011. The experiments were first carried out in Vodňany, then in České Budějovice. The first experiment took place in temperatures ranging from 10-30°C. The unfertilized roe were preserved at these temperatures for periods of 0, ?, ?, 1, 2, 4 and 6 hours. Afterwards the fertilization was done using collected sperm and egg samples incubated at 25°C. For the second experiment which took place at a temperature of 25°C, the samples of freshly smeared roe were seeded into dry dishes, poured with water at time intervals from 0 to 10 minutes (at 30 second intervals), then the previously collected sperm was added. Both experiments were done repeatedly for roe that originated from a total of 8 female fish. In both cases, the seeded pieces were counted for the egg samples in the dishes following washing. Their fertilization was evaluated (%) as well as their hatching (%).
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