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Umělý výtěr karase obecného
The thesis briefly summarizes the available information in the field of crucian carp biology. The experimental part includes, firstly, monitoring the effect of water temperature during the latency period in reproductive females affects the success of artificial spawning, the survival of eggs to the eyespot stage, the length of the latency interval in hours and in clock degrees, the relative fecundity of reproductive females and the pGSI. In the second part of the experiment, secondly, the effect of the method of unstickness eggs on the survival of eggs to the eyespot stage. To test the effect of temperature during the latency interval, the females (mean weight 329 +- 60 g) were divided into 7 groups (n = 5). The individual groups of reproductive females were placed in separate tanks with average water temperatures of 15.4, 17.2, 18.9, 21, 23.2, 25.2 and 27.2 °C. Females and males were injected with the hormone Ovopel (1 pellet per 1 kg of fish). Before injection and artificial spawning, the reproductive fish were anaesthetized with clove oil (0.03 ml.l-1). The each group of females were artificially spawned, the eggs were seeded with a mixture of sperm from three males, activated with hatchery water and unsticked with cow's milk diluted with water (1:9). Incubation of eggs was carried out in small experimental Zug bottles (0.45 l) at an average temperature of 21 °C. The highest number of ovulated and artificially spawned females was found at temperatures of 21 - 25 °C (80 %). At lower and higher temperatures the success of spawning was lower. A close positive linear dependence of the latency interval length (in hours) on water temperature was found in the monitored range of 15.5 - 27.2 °C (y =-1.5062 x + 50.663; R2 = 0.924). The length of the latency interval at 21 and 23 °C was 18,4 +- 0,9 and 12,4 +- 0,2 h, respectively 387 +- 18 and 289 +- 5 h°. The eggs have a yellow-brown to green-brown colouration, the average weight of one unswollen eggs is 1,10 +- 0,07 mg (corresponding to 911 +- 51 thousand eggs in 1 kg of eggs). In contact with water, the eggs are very sticky. The highest relative working fecundity was achieved at 21 and 23 °C (71,9 +- 10 and 75,9 +- 34 thousand eggs per 1 kg of female). The average survival rate of eggs to the eyespot, originating from artificially spawned females kept during the latency interval at temperatures between 18,9 - 23,2 °C, ranged from 92.9 +- 0.5 to 99.6 +- 2.2 %, and was lower at 17.2 and 27.2 °C (86.2 +- 0.6 respectively 74.2 +- 3 %), differences between groups were statistically significant. In evaluating the effect of unsticking preparations on the survival of eggs to the eyespots, the highest survival was achieved with milk (71.9 +- 7.3 %). Statistically conclusively lower survival was found with tannin (47.4 +- 0.4 %) and acetylcysteine (48.4 +- 8.6 %). The achieved results can be used in artificial spawning of crucian carp as part of rescue breeding.
Vliv teploty na schopnost oplození a líhnivosti při krátkodobém skladování neoplozených jiker síha peledě (Coregonus peled)
The northern whitefish Coregonus peled (Gmelin, 1788), originally from Russia, was introduced to the Czech Republic in 1970 for its tasty meat and good growth ability. Breeding of this species has been very popular in the past. Currently, thanks to the fish-eating predators, traditional breeding of this species is on decline. The aim of this M. Sc. Thesis was to sumarize the avaible information in the field of peled biology, artificial propagation and also information about effect of temperature on the ability of fertilization and hatching for short-term of unfertilized eggs in other salmonid species. In the practical part, the influence of temperature and length of storage of stripped, unfertilized eggs of peled on fertilization, survival to eyed eggs and hatching were observed. Unfertilized eggs were divided into five bowls and deposited in thermo boxes, which were tempered to 2.5, 5, 7.5, 10 and 12.5 °C. After time intervals of 1, 4, 12, 24, 36, 48, 60 and 72 hours, approximately 100 - 200 eggs were taken from each thermobox, which were fertilized with fresh sperm (collected from several males) and water from the hatchery. The fertilized and purified eggs were moved to the incubators with continuously inflow of fresh water. Dead eggs were removed and recorded. Subsequently, fertilization, eyed eggs and hatching eggs were determined. The resulting values of these parameters were expressed as a percentage of the total number of used eggs. High levels of fertilization and survival to eyed eggs were achieved when stored within 1 day from eggs stripping at all temperatures except the highest temperature of 12.5 ° C. As the interval gradually lengthened, the fertilization and survival parameters also decreased, most notably at 7.5 and 10 ° C. To obtain the largest possible amount of fry in fishing practice, it is recommended to store eggs at 2.5 and 5 ° C, up to 48 hours after ova stripping. At higher temperatures, the effective storage time is reduced to 12 hours. Storing eggs for longer than 48 hours, in practical terms has no meaning. At the same time, it was found that at the above-mentioned optimal temperatures for storing eggs (2.5 and 5 ° C), the best hatching results were obtained when storing stripped eggs for 12 hours. Not only for longer, but also for shorter storage lengths, the values of this parameter were lower.
The Tench Fertility and Condition Changes in Fishery HLuboká
The main present effort in the controlled fish reproduction is the finding universal preparation which are suitable for the ovulation induction of large fish species spectra. The preparation should not cause hight after-spawn mortality of generation fish and it is wantable to repeat inorganic spawn in following seasons too. The experiment which reviewed the tench fertility and condition with using several hormonal preparation was realized in working condition of Fishery Hluboká (hatchery Mydlovary) in 2006 {--} 2007. The gained generation material was separated in several intervals by weight and it was detected the working fertility in percent and semination in percent for individual weight categories. The experiment was realized by using following preparation: Ovopel, Dagin, Supergestran, Kobalerin.
Využití hormonálních přípravků při výtěru podoustve říční(Vimba vimba)
DUDA, Pavel
The aim of this bachelor thesis was to find out which of the three used hormonal products was the most effective for a hormonal induction during spawning of a vimba bream. The three mentioned hormonal products were Chorulon, Supergestran and Ovoplel, which are commonly used in fishing practice. The experiment was implemented in 2015 and the fish which were used for the experiment came from an experimental pond breeding VÚRH FROV JU in Vodnany. The hormonal products were injected to the fish in a single dose. We were examining how the fish would respond to the injected hormone and whether the maturing of the fish eggs and subsequent ovulation would proceed. The experiment clearly showed that Supergestran was the most suitable product for the hormonal induction of the vimba bream.
The influence of hormonal treatment on succes of induced controlled spawning of Weather loach (Misgurnus fossilis)
ŽÁK, Jakub
The Weather loach (Misgurnus fossilis) is one of the fastest disappearing species in Europe. This is the reason for finding a solution for support of natural populations. The possible solution is artificial stripping under controlled conditions and stocking of offspring into appropriate habitats. Carp pituitary extract (CPE) has been used for controlled stimulation of oocyte maturation until now. The usage of CPE in fishery is decreasing because of health risks. The aim of this thesis was the comparison of different hormonal stimulants on selected aspects of artificial spawning of Weather loach. Stimulants were injected intramusculatury in two doses. Females were taken from experimental pond in Vodňany FROV (individual body weight 31 - 59 g). Temperature was kept at 17.9 +/- 0.13 °C. The lowest percentage of ovulating females (80 %) was achieved after stimulation by Dagin (dose: one ampula per 40 kg). With use of the other stimulants, all females were ovulating. The highest relative amount of stripped eggs in relation to pre-stripping weight of female was reached after application of Ovaprim in dose 1 ml×kg-1 (170 +/- 19 ks×g-1). The smallest amount of stripped eggs was obtained after application of Pregnyl in dose 1500 IU×kg-1 (85 +/- 38 ks×g-1), Pregnyl in dose 3000 IU (97 +/- 24 ks×g-1) Chorulon 1500 IU (86 +/- 32 ks×g-1) respectively. The shortest latency interval was observed after stimulation by CPE (18 hours) and by Ovaprim in dose 2 ml×kg-1 (23 hours) respectively. Interval of latency was longer than 31 hours in females stimulated with lower doses (1500 IU) of a stimulant without dopaminergic inhibitor. The best synchronization of ovulation was observed after stimulation by CPE (1 hour) and Chorulon in dose 3000 IU and 1500 IU (2 hours) respectively. The egg of weather loach contained 53 % of carbon, 21 % of oxygen, 12 % of nitrogen, 8 % of hydrogen and 0.3 % of sulfur. Chemical composition was significantly different only in oxygen concentration between females stimulated by CPE and 2 ml×kg-1 Ovaprim. In general, worse results of artifficial spawning aspects were observed after stimulation by stimulants without dopaminergic inhibitor. The results in this thesis show which accessible commercial hormonal stimulants used in stimulation of other fish species are useable for controlled reproduction of weather loach. Ovopel and Ovaprim can be recommended for stimuation of ovulation or spermiation of weather loach.
Assessment of effect of different methods of hormonal induction ovulation in females of common carp
By hormonally induced artificial propagation of general carp (Cyprinus carpio), originally from pond breeding, were 3 groups of stripped eggs to broodstock weighted 3829 +- 729 kg intramuscularly injected in interval of 12 hours. They were intramuscularly injected in two different doses by diffrent preparations: 1.extract of carp hypophysis (CPE) in dose 0.5 + 2,5 mg×kg-1, 2. Ovopel containing GnRHa and dopamine antagonist (DA) in doses 0.5 + 2 mg×kg-1, 3. Dagin containing GnRHa and DA in doses 5 + 20 mg×kg-1. Single groups of stripped eggs (n = 17 to 19 pcs) were placed into separated ponds. The avarage temperature of flowing water was 20.9 +- 0.9 °C. The highest ratio of stripped eggs to broodstock was observed following injection of Dagin (89.5 %) and by Ovopel (82.4 %). The highest mortality of stripped eggs to broodstock was observed by using CPE (76.5 %). The highest values of gonadosomatic index (pGSi) propagated stripped eggs were observed in groups injected by Dagin (18.4 +- 5.2 %) and Ovopel (17.6 +- 5.9 %), the lowest values were observed by using CPE (16.3 +- 6.5 %). The relative labour fertility of stripped eggs was very stable ( Ovopel 117000 +- 39000 pcs×pcs-1, Dagin 116000 +- 32000 pcs×pcs-1, CPE 115000 +- 45000 pcs×pcs-1). The highest average wet weight of one egg was 1.42 mg (CPE) and 1.59 mg (Dagin), only this variation was statically provable ( = 0.05). The period of latence from the second hormonally injection to the artificial propagation (after ovulation) was 15.5 +- 1.2 h (resp. 324 +- 25 h°) with Ovopel, with CPE 16.4 +- 1.0 h (so 341 +- 22 h°) and with Dagin 16.5 +- 0.4 h (so 345 +- 7.6 h°). The statistically important difference ( = 0.05) was observed only in period of latence between groups of fish injected by Ovopel and Dagin. The highest propagation of stripped eggs in incubation bottles was observed by using extract of Ovopel (80.9 +- 14.9 %), then by using CPE (75.0 +- 17.1 %) and Dagin (74.8 +- 9.6%). By comparing cumulate parameter,which is given by number of fertilized eggs in one kilo after hormonally injection and after 24 hours of incubation in incubation bottles (including all followed aspects: % of stripped eggs, the relative labour fertility of stripped eggs and number of fertilized eggs), were observed synthetic preparations GnRHa like more effective than CPE, which contains natural carp gonadotropin. The highest values of this parameter were found out in Ovopel groups (78000 pcs×kg-1) and Dagin groups (77000 pcs×kg-1). The lowest value was observed in CPE group (66000 pcs×kg-1).
The use of artificial and semi-artificial spawning in the present breeding of common carp
This thesis is focused on the use of artificial and semi-artificial spawning substrates in the current breeding of common carp (Cyprinus carpio, L.) a literature review of this species was processed in relation to reproduction, as well as of the spawning methods (natural, semi-artificial, artificial). Results are drawn from the experimental part (2 spawns: a semi-artificial spawn in the institution for experiments at the Fishery School in Vodňany and an artificial spawn in the fish hatchery at the Research Institute of Fish Culture and Hydrobiology in Vodňany). In both spawns, hormonal stimulation of brood stock was carried out. In the artificial spawning the amount of obtained sex products of individual breeds was assessed. At the same time, a questionnaire survey was conducted at 11 fish-breeding companies engaged in their own production of yolk sac fry. The responses obtained from the survey and findings from the experimental part of spawnings were compared with bibliographic sources which the following conclusions were reached from. It was confirmed that at present a massive carp fingerling production from artificial spawn ensuring optimized conditions dominates over the Dubravius method of semi-artificial spawning which is used only rarely. The production of mirror carp is currently higher than the production of scaly carp. Among the bred mirror breeds the Hungarian mirror carp (M2) prevails, nonetheless it depends on the individual fishery company which form of carp they choose to satisfy the market demand.
Hormonal induction of ovulation in whitebarred catfish (Agamyxis pectinifrons)
KNOWLES, Jindřiška
The aims of presented work are reviewing of current knowledge about biology and artifical reproduction, evaluation of dopamine inhibition of LH secretion and identification of optimal hormonal treatment of ovulation in tropical whitebarred catfish. Two trials were conducted in years 2012 and 2013. The experiments differed from each other only in the water temperature 29,5 °C (Experiment No.1) and 26 °C (Experiment No.2). In each experiment, the fish were divided into 4 groups. Group A was injected only with mGnRHa, group B was injected with dopamine inhibitor metoclopramide, group C was injected with mGnRHa plus metoclopramide and group D was injected only with physiological saline (0,9 % NaCl). Ovulation occurred only in the groups injected with the combination of GnRHa and dopamine inhibitor, however in both experiments. In Experiment No.1, the ovulation rate was around 60%, relative fecundity was 331,025 +- 47,508 eggs . kg-1, latency interval was at 10.3 +- 0.6 hours and the fecundity index was determined at 13, 8. In Experiment No. 2 ovulation, the level of ovulation was 50%, relative fecundity was 408,561 +- 34,934 pieces of eggs . kg-1, latency interval was 13.7 +- 0.7 hours and fecundity index was 15.35. The results clearly show a strong inhibition of dopamine on LH secretion and show that the combination of GnRHa with dopamine inhibitor can be successfully used to induce ovulation in whitebarred catfish.
Hormonal induction of artificial stripping of the female European catfish (Silurus glanis)
The optimalization way of hormonal induction ovulation females European catfish Silurus glanis was the aim of experiment with the help of hormonal preparate on the base functional of the analogue GnRH. Fish with females were fish out in the ponds early in june and injected by hormonal preparates CPE, Dagin and Ovopel. Was monitoring latency time in dependency of water temperature, percent of ovulated females, relative weight of ovulated eggs, fertilization eggs and hatching performance.
Artificial spawning and semiartificial spawning of pikeperch (Stizostedion lucoperca) in controled conditions for fish farming
BLECHA, Miroslav
Pikeperch (Stizostedion lucioperca), along with pike (Esox lucius), the main types of supplementary fish reared in pond aquaculture. For its very high quality meat and fish species used by the catering trade. To ensure supply of quality embrií hatching and fish for the needs of fish farmers need to master, and where artificial spawning semiartificiale.

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