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The aim of this work was to develop methods of artificial European catfish reproduction outside of its natural spawning season using thermal and hormonal stimulation. Ovulation was induced with combined hormonal stimulation using a priming dose of Ovopel (0.3 granules in one dose or 0.2 and 0.3 granules in two doses per kg of female body weight) and a resolving dose of carp pituitary extract (CPE) (3 mg per kg of female body weight). The latency period between the doses was 24 hours. The males were stimulated with one dose of Ovopel (1 granule per kg of body weight). The results obtained indicated that the application of the appropriate thermal and hormonal stimulation, without light stimulation, can induce artificial spawning in the European catfish between January and August. It was revealed that the time between the injection of the resolving dose and egg collection decreased over this period. Thus, ovulation could be stimulated faster than in winter and spring. The number of eggs obtained in pre-season spawning was greater when the thermal treatment was longer. The results obtained indicate that the application of Ovopel in two stimulation doses instead of one was advantageous for the effectiveness of European catfish pre-season spawning, the number of eggs obtained as well as its survival. The results obtained during artificial European catfish reproduction conducted before, during, and after its natural spawning period were comparable.
The aim of the study was to compare the effectiveness of hormonal stimulation of the female ide (Leuciscus idus L.), following the application of two commercial preparations concerning different GnRHa combined with dopamine inhibitors: Ovopel and Ovaprim. Ide spawners were bred under controlled conditions. The examined parameters included the percentage of ovulating females, time of ovulation and the rate of embryo survival to the eyed-egg stage. The growth and survival rates for larvae produced by farm and wild fish were compared. Stimulation with Ovopel resulted in a shorter latency time (36), whereas stimulation with Ovaprim resulted in a higher percentage of live embryos at the eyed-egg stage (79.7 %). Eggs was obtained from 20% of females in the control group, whereas in treated groups it was at level 90–100%. No differences were found between the growth rate of the ide larvae produced by the farm fish and that obtained from wild fish.
The aim of the experiment was to identify the possibilities of stimulating pikeperch spawning with human chorionic gonadotropin (hCG) and Ovopel, a mammalian GnRH analogue (D-Ala⁶ Pro⁹ NEt-mGnRH) with a dopamine inhibitor (metoclopramide). Pikeperch spawners were caught with trap gear (fyke-nets) during the pre-spawning season from the Tałty and Tałtowisko lakes (Masurian Lakeland, northern Poland). After transport that lasted an hour, the fish were placed in tanks in a recirculating system and then segregated by sex. The females were divided into five experimental groups, each containing six specimens. The fish were injected twice at 24 hour intervals with hCG (group I - 200 and 200IU kg⁻¹ body weight (BW); group II - 200 and 500IU kg⁻¹ BW), Ovopel (group III - 0.25 and 0.50 pellets kg⁻¹ BW; group IV - 0.25 and 1.0 pellets kg⁻¹ BW) or 0.7% NaCl solution (group V, control - 0.2 and 0.5 cm³ kg⁻¹ BW). The effects of the hormonal stimulation expressed as the percentage of ovulating females, the degree of spawning synchronicity, and survival of the embryos to the eyed-egg stage were highly differentiated. The highest percentages of spent fish were obtained in the group stimulated with hCG - 83.3% (group I) and 100% (group II) of the females ovulated. The development of the oocytes in this group was rapid and synchronous, which was reflected in the shortened and relatively similar latency period (47 - 57 hours following the first injection; mean ≈ 51 hours) in individual females. No impact was noted with regard to hCG dose (400 vs. 700 IU kg⁻¹ BW) on the latency time or on egg quality. Ovopel did not positively affect either oocyte maturation or pikeperch ovulation. None of the fish from group III ovulated, and in group IV, as in the control group, eggs were obtained only from three (50%) females. In contrast to group V, the eggs of females stimulated with Ovopel were of low biological quality and survival to the eyed-egg stage ranged from 0 to 8%. Higher mortality among the females was also noted, especially in group III. The experiment indicated that hormonal stimulation with hCG is effective, while that with Ovopel was surprisingly ineffective.
The aim of the study was to determine the basic quality parameters and selected biochemical markers of asp, Aspius aspius (L.), semen after spermiation was stimulated with Ovaprim and Ovopel. Sperm motility and concentration, osmotic pressure, total protein content, and activities of acid phosphatase (AcP), lactate dehydrogenase (LDH), and b-N-acetylglucosaminidase (b-NAG) were determined. It was revealed that higher sperm motility and concentration and higher seminal plasma protein content were obtained after stimulation with Ovaprim. The osmotic pressure of the seminal plasma estimated for males following the administration of Ovopel was higher than after they had been treated with Ovaprim. It was determined that enzyme activity in the seminal plasma of the fish stimulated with Ovaprim was higher in comparison with results obtained after they had been treated with Ovopel. Significant, positive dependencies were confirmed between the concentration of sperm and the total protein content in the seminal plasma (r2 = 0.492) and the activity of b-NAG (r2 = 0.779); among the total protein content in the seminal plasma and the activities of AcP (r2 = 0.476), LDH (r2 = 0.564), and b-NAG (r2 = 0.738); and between the activities of AcP and LDH (r2 = 0.483) and between the activities of LDH and b-NAG (r2 = 0.844).
Background. Obtaining the appropriate quantity of milt and spermatozoa of biologically good quality depends on a number of environmental factors. Additional factors may be involved while using a hormonal stimulation. The aim of this study was to analyse the effect of time, after stimulation with Ovopel [(D-Ala6, Pro9-NEt)-mGnRH+metoclopramide] (1 granule∙kg-1 body weight) on semen quality indicators of common carp, Cyprinus carpio L., over the period of 72 h post injection. Materials and methods. The total volume of milt (TVM, mL), volume of milt per 1 kg of the male body weight (VOM, mL∙kg-1 b.w.), total sperm production (TSP, ×109), and their concentration (×109 mL-1) in milt were determined. Additionally, the motility of spermatozoa (%) by means of the subjective method and the osmotic pressure of seminal plasma (mOsm∙kg-1) were determined. The milt was collected 24 h (group I, n = 10), 48 h (group II, n = 10), and 72 h (group III, n = 10) after stimulation with Ovopel. Results. No significant differences (P > 0.05) in the main parameters of milt i.e., the motility and concentration of spermatozoa in the milt, as well as in the osmotic pressure of seminal plasma were found between the experimental groups of the fish. Higher TSP and VOM values were recorded 24 h after Ovopel injection compared to samples obtained after 72 h (P <0.01 and P < 0.05, respectively) and 48 h (P > 0.05). TVM values were also higher at 24 h after the injection than those noted at 48 and 72 h (P < 0.01). Conclusion. The lack of significant differences in the motility and concentration of spermatozoa in milt at 24, 48, and 72 h after injection indicate that time after Ovopel administration does not have an influence on the main indicators of common carp milt quality. However, we noted significant differences in TSP, TVM, and VOM between samples obtaining 24 h and 72 h after hormonal stimulation. The highest quantity indicators i.e., the number of spermatozoa in milt and volume of obtained milt noted for samples obtained after 24 h suggest that this time is better for milt sampling than time after 48 and 72 h.
The objective of this study was to evaluate the economic effectiveness of various hormonal products for stimulating the reproduction of the cultured and wild forms of the common barbel Barbus barbus (L.). Three hormonal products were analyzed: Ovopel, Ovaprim (cultured and wild fish) and hCG (cultured fish). The economic effectiveness of hormonal stimulants was analyzed in view of ovulation rates, the price of hormonal products and spawner mortality rates. The cost of hormonal injection per 1000 eggs and 1000 hatchlings was adopted as an indicator of economic effectiveness. The best results were reported for hormonal stimulation using synthetic GnRH analogues during induced spawning of the barbel in a group of cultured fish. The above product’s effectiveness in the controlled spawning of cyprinids is demonstrated by high ovulation rates and high embryo survival rates.
This study determined the effect of hormonal stimulation of the wild female nase, Chondrostoma nasus (L.), on its basic reproduction indices (percentage of ovulations, latency time, embryo survival) and the economic profitability of its use. Two commercial preparations were used in the experiment: Ovopel and Ovaprim. They were used separately (group 1 and 2 for Ovopel and Ovaprim, respectively) and in combination (group 3), where Ovopel was given in initial and Ovaprim in resolving injection. The study found a high effectiveness of all the hormonal treatments applied (ovulation rate 90–100%, latency time 36 h, embryo survival rate 78.6–81.2%) (P>0.05), which may be evidence of the greater susceptibility of the nase to stimulation with the less active mammalian analogue of GnRH as compared to other species of rheophilic cyprinids. In consequence, the lowest cost of hormonal stimulation (0.59 EUR per 10,000 viable embryos) was achieved with Ovopel. Using the hormonal agents in combination (in group 3) reduced the cost of stimulation by 0.17 EUR as compared to Ovaprim (group 2), where the cost was the highest (1.57 EUR per 10,000 viable embryos). The results presented in this study are providing useful information for fish breeders who manage wild populations of the nase and other species of rheophilic cyprinids.
Assessment of the economic effectiveness of hormonal stimulation application in reophile cyprinid fish reproduction based on the example of asp Aspius aspius (L.) and ide Leuciscus idus (L.) was the goal of the studies presented in this paper. Three hormonal preparations: Ovopel, Ovaprim and carp pituitary were tested during this study. Economic effectiveness of application of those hormonal preparations for asp and ide reproduction stimulation considering the relative working fertility of asp and ide, effectiveness of the selected hormonal preparations and their price were assessed. The cost of hormonal injection per 1000 spawn grains and per 1000 spawn grains in eyed stage was assumed for the measure of economic effectiveness. In case of both studied species injections with Ovaprim and Ovopel were more economic than stimulation with carp pituitary. This is linked to the high application effectiveness of GnRH analogues with dopamine inhibitors found in controlled reproduction of asp and ide. The effectiveness of those hormonal preparations is confirmed by a high percentage of ovulations as well as the high survival rate of the embryos to the eyed stage.
The aim of the study was to compare the female dace Leuciscus leuciscus (L.) and ide Leuciscus idus (L.) hormonal stimulation effectiveness with two preparations (Ovopel and Ovaprim) separately and in combination. The experiment was conducted under controlled conditions. During the experiment the percentage of ovulating females, ovulation time and survival of embryos to the eyed stage were recorded. Stimulation with Ovopel resulted in shorter ovulation appearance time in females of both species (48–50 h for dace and 36–38 h for ide) while stimulation with Ovaprim in a higher percentage of live embryos in the eyed stage (almost 80 and 60% for dace and ide respectively). The highest hormonal stimulation effectiveness was recorded in the group where a combination of those two hormonal substances was applied as shortening of the time for achievement of spawning readiness (48 and 36 hours for dace and ide respectively), a significant ovulation synchronization and the highest embryos survival rates (almost 80 and 70% for dace and ide respectively) were recorded.
Badania przeprowadzono na 45 matkach rasy merynos polski, które po regulacji funkcji układu rozrodczego we wczesnym okresie poporodowym, metodą Chrono-Gest, wydały potomstwo. Tą samą metodą 28-29 dnia po wykocie matki powtórnie poddano regulacji hormonalnej. Jagnięta w każdym cyklu pozostawały przy matkach do czasu odsadzenia w wieku 100 dni. W drugim sterowanym cyklu rozpłodowym uzyskano 22.2% płodności, 130% plenności oraz 69.2% odchowu jagniąt (plenność gospodarcza 20%). W porównaniu z grupą kontrolną (35 matek) nie stwierdzono ujemnego wpływu zwiększenia częstotliwości wykotów na kondycję matek i ich mleczność oraz wzrost i rozwój pozyskiwanych jagniąt
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