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Vliv teploty na udržení schopnosti oplození a líhnivosti při přechovávání neoplozených jiker u keříčkovce červenolemého
BORŮVKA, Vít
When hormonally induced artificial spawning of african catfish (Clarias gariepinus), was several female injected intraperitoneally in one dose preparation Ovopel at doses of 1.5 pellet × kg-1. Females were kept separately in the tanks at a temperature of 21.5 °C. All females were spawned at the same time latency 19.2 hours. Eggs from three spawned females were mixed and divided into 6 doses. Each batch was placed into thermoboxes at temperature 5 °C, 10 °C, 15 °C, 20 °C, 25 °C and 30 °C. These eggs were stored in thermoboxes and after times of storage 0.5 h, 1 h, 1.5 h, 2 h, 3 h, 4 h, 6 h, 8 h, 10h, part of the eggs (approximately 50 to 100 pieces) were taken out from each thermoboxes in three replications and was placed into individuals cups and fertilized by adding 5 drops of sperm and 20 ml of water. In these samples were subsequently observed fertilization, hatching rate and survival rate. When watching fertilization was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 2 hrs. (61.6 +- 5.81 % - 47.7 +- 1.48 %), at 10 °C in times 0.5 - 1.5 hrs. (70 +- 6.7 % - 62.1 +- 8.9 %), at 15 °C in times 0.5 - 3 hrs. (59.6 +- 9.4 % - 59.6 +- 2.9 %), at 20 °C in times 0.5 - 3 hrs. (61.4 +- 3.6 % - 56.1 +- 2.5 %), at 25 °C in times 0.5 - 4 hrs. (55.5 +- 7.2 % - 49.7 +- 9.3 %) and at 30 °C in times 0,5 - 3 hrs. (61.6 +- 10.3 % - 51.8 +- 17.8 %). When watching hatching rate was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 - 1 hrs. (28.4 +- 2.9 % - 21.1 +- 9.5 %), at 10 °C in times 0.5 - 1 hrs. (36.6 +- 17.3 % - 22.1 +- 7 %), at 15 °C in times 0.5 - 2 hrs. (34.1 +- 5.5 % - 26.9 +- 5.1 %), at 20 °C in times 0.5 - 2 hrs. (33 +- 8.2 % - 28.8 +- 1.6 %), at 25 °C in times 0.5 - 4 hrs. (31.4 +- 6.2 % - 15.3 +- 13.5 %) and at 30 °C in times 0.5 - 2 hrs. (33.1 +- 9.2 % - 21.2 +- 8 %). When watching survival rate was in individual temperature the highest values and also statistically non-significant difference ( = 0.05) achieved: at 5 °C in times of fertilization 0.5 - 1 hrs. (20.1 +- 6 % - 13 +- 3.3 %), at 10 °C in times 0.5 - 3 hrs. (19.8 +- 15.31 % - 3.1 +- 3 %), at 15 °C in times 0.5 - 6 hrs. (23.3 +- 9 % - 5 +- 2.8 %), at 20 °C in times 0.5 - 2 hrs. (22.4 +- 1.9 % - 15.1 +- 5.2 %), at 25 °C in times 0.5 - 4 hrs. (18.7 +- 4.4 % - 4.1 +- 1.9 %) and at 30 °C in times 0.5 - 1.5 hrs. (26.2 +- 5.5 % - 21.4 +- 6.8 %). Suitable temperatures for the storage of unfertilized eggs after spawning are two hours before fertilization at temperatures from 15 to 30 °C. Other suitable temperatures which are useful for storage are temperatures 15 to 25 °C, for preservation after 3 hrs. and longer after fertilization.
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Assessment of effect of different methods of hormonal induction ovulation in females of common carp
BORŮVKA, Vít
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).
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