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1.
Enzyme treatment to eliminate egg stickiness in tench, European catfish and common carp was compared with standard methodology in an attempt to decrease time consuming under hatchery conditions. Eggs of tench and E. catfish were exposed to an alcalase enzyme MERCK EC 3.4.21.14 (0.6 AU g?1) solution 3 min after egg fertilization for 2 min. The best enzyme concentration in tench and E. catfish was 10 and 20 ml l?1 of enzyme, respectively. The eggs of c. carp were successfully destickiness with ALCALASE DX (2.5 AU g?1) using two concentration of enzyme (2 ml l?1 and 20 ml l?1) from 8 to 20 min after fertilization.  相似文献   
2.
This study tested KUROKURA solution (Kurokura et al., 1984, Aquaculture 37, 267–274) and its modifications (by increasing NaCl content to 160, 180 and 200 mM) on immobilizing properties for sampling and short-term preservation of potential motility of tench spermatozoa. The immobilizing solution is used because, when collected, the sperm of most samples is contaminated by urine, causing spermatozoa to be of poor quality, with low motilities and velocities (almost 0), thus resulting in a worsened fertilization and hatching rate. Sperm was sampled with a syringe containing an immobilizing solution (IS), allowing an IS:sperm ratio of 2:1, under aerobic conditions at 0–4°C. This sperm solution was stored for 10 h and untreated sperm was collected prior to fertilization as a control. Spermatozoa quality was evaluated for the cell motility and velocity parameters and also for fertilization ability and hatching rate. Results obtained for tench sperm motility, velocity, fertilization and hatching rate showed that only sperm collected in the various immobilizing solutions can be successfully used for artificial insemination and preservation after 10 h at 0–4°C. The best immobilizing solution was found to be KUROKURA 180 (180 mM NaCl, 2.68 mM KCl, 1.36 mM CaCl2· 2H2O and 2.38 mM NaHCO3), giving a fertility and hatching rate of 41%, with no change in rates after 10 h storage of sperm. Control sperm without immobilizing solution showed a fertilization and hatching rate of only 6–7%.  相似文献   
3.
Changes in ionic composition as Na+,K+, Ca2+ and Mg2+, osmolality inseminal fluid, percentage of motile spermatozoaand velocity were investigated in response toCPP and different dosage of LHRHa. The lowestvelocity of sperm was observed after use CPPtreatment. The velocity of spermatozoa,significant main effect of the treatment(P < 0.0001) and the time of sperm collection(P < 0.0104) were evaluated. The osmolality ofseminal fluid was different betweenexperimental groups of LHRHa (48.0–62.7mOsmol.kg–1) and CPP (33.0–46.3mOsmol.kg–1) treatments. The osmolalitywas significantly higher on the first day andone-half, then declined on day three, rangingfrom 33.0 to 62.7 mOsmol.kg–1. Analysisof variance showed significant main effects ofthe treatment (P < 0.0001) and the time ofsperm collection (P < 0.0002) on the osmolalityof seminal fluid. The level of Na+ andK+ ion was different between experimentalgroups of LHRHa and CPP treatment. The highestconcentration of 11.11 mmol.l–1 wasobserved at Na+ ion. Then theconcentrations declined on the level 1.56, 0.52and 0.36 mmol.l–1 for K+, Ca2+and Mg2+ ions, respectively. There werehighly positive correlations between osmolalityof seminal fluid and dosage of LHRHa treatment(r = 0.84), velocity of spermatozoa andosmolality of seminal fluid (r = 0.57) andosmolality of seminal fluid and Na+concentration at seminal fluid (r = 0.70).Injection with LHRHa increased quality of spermas velocity of sperm, level of Na+,K+ and osmolality at seminal fluidcompared to CPP treatments.  相似文献   
4.
Exogenous steroids alter sex differentiation in fish substantially. In the present study we have evaluated the effects of 17α-methyltestosterone (MT) and oestrogen receptor antagonist Tamoxifen (TA) on gonadal development and skewness of the sex ratio in all-female tench juveniles. In the first two experiments, sexually undifferentiated juveniles were orally treated with three doses of MT and TA (50, 100 and 150 mg kg−1). Both the treatments resulted in a moderate dose-dependent masculinization, with neomale production ranging from 17% (50 mg kg−1) to 26% (150 mg kg−1) for the MT only treatment, and from 0% (50 mg kg−1) to 27% (100 mg kg−1) only for the TA treatment respectively. In the third experiment treatment of sexually differentiated tench females with single steroid treatments or combinations of the two resulted in populations composed of females and intersex individuals. The significantly highest occurrence of intersex individuals (45.5%) was found in the group subjected to combine treatment of MT+TA (150+200 mg kg−1). No masculinization effect of the single or the combined treatment occurred. It can be concluded that oral treatment with MT or TA only slightly modifies the normal process of sex differentiation in gynogenetic tench juvenile, but treatment with the above-mentioned combinations has a highly significant potential to skew the sex ratio in sexually differentiated tench females. However, from an applied point of view, the treatment procedure will need optimization before use at a commercial level.  相似文献   
5.
Sperm quality of Barbus barbus L. was compared among the three following dietary regimes: Group A, fed 100% commercial diet (Karpico™ containing 33% crude protein and 6% fat), Group B, fed 78% commercial diet and 22% frozen chironomid (Chironomus plumosus) larvae, and Group C, fed 56% commercial diet and 44% frozen chironomid larvae. Concentrations of polyunsaturated fatty acids (PUFAs) in Group A, B, and C were 39.1, 42.0, and 44.6, respectively, as a percentage of total fatty acids. Sperm morphology, volume, concentration and motility, total number of spermatozoa, and osmolality of the seminal plasma were compared during the spawning season. Dietary regime did not influence sperm volume, concentration, or total number of spermatozoa, osmolality of seminal plasma, or the percentage of motile sperm, but significantly affected sperm morphology (except for anterior and posterior parts of the midpiece) and sperm velocity (P < 0.05). Groups B and C showed similar sperm characteristics during the spawning season compared to Group A. Almost all parameters changed either among or within groups during the spawning season, suggesting differences in terms of the optimal time for sperm collection. The best time for sperm collection was March for Group A, but April for Groups B and C, when the osmolality of the seminal plasma measured 289 mOsmol kg−1 and sperm motility was maximal. Spermatogenesis, hydration, and cell decomposition were confirmed as the three major parameters controlling sperm characteristics during the spawning season. The possible correlation between sperm morphology and motility requires further study.  相似文献   
6.
Fisheries Science - The cleavage pattern of a vertebrate’s embryo is either holoblastic (complete) or meroblastic (partial). Sturgeon and other basal bony fishes represent a transition of the...  相似文献   
7.
Oxidative stress is a possible source of spermatozoa function deterioration. Seminal fluid (SF) protects spermatozoa against reactive oxygen species (ROS) attack during development in testes and transit through the reproductive tract. Spermatozoa curvilinear velocity and percent of motile cells as well as changes in thiobarbituric acid-reactive substance (TBARS) content, superoxide dismutase, and catalase activity, and uric acid concentration in SF were evaluated in sterlet sperm collected from testes 24 h after hormone induction of spermiation and from Wolffian ducts at 12, 24, 36, and 60 h after hormone injection (HI). While testicular spermatozoa motility was not initiated in activating medium, Wolffian duct sperm showed low motility at 12 h, significant increase at 24 and 36 h, and decrease at 60 h. Testicular SF was characterized by the highest level of TBARS and activity of studied enzymes compared with SF from Wolffian duct sperm at 24 h post-HI. In fluid from Wolffian duct sperm, a significant increase in TBARS content was shown at 36–60 h post-HI. In contrast to testicular SF, in SF from Wolffian duct sperm, this increase was not counterbalanced by changes in the studied variables of antioxidant system. This may be the source of the observed decrease in spermatozoa motility parameters 60 h post-HI. The results may confirm a dual role of ROS in fish sperm physiology. The data with respect to decrease in sturgeon spermatozoa motility parameters at 60 h post-HI should be taken into account in artificial sturgeon propagation.  相似文献   
8.
The great diversity of optimal UV irradiation doses are used for DNA inactivation in fish sperm forcing authors to repeat optimization of irradiation treatment every time. Analysis of sperm UV irradiation protocol for induction of gynogenesis showed the importance of sperm UV light absorption estimations. The UV absorption investigation in Siberian sturgeon sperm showed average extinction coefficient 7.69 × 10?8 ± 1.04 × 10?8 cm2. It is resulted in high heterogeneity of UV irradiation of undiluted sperm samples. Therefore, it is strongly suggested to specify doses only with defined concentration of spermatozoa; otherwise, the difference in absorbance level between samples can bring a significant error to optimal UV dose estimation. This was confirmed by UV-irradiated sperm motility investigation. Results of motility investigation of UV-irradiated sperm revealed high sensitivity of Siberian sturgeon spermatozoa motion mechanisms to UV irradiation, with complete loss of motility after homogeneous UV irradiation at doses above 2,000 J/m2. Partial gynogenesis was conducted using diluted and undiluted sperm. Ploidy level of hatched larvae was estimated by flow cytometry. Percentage of haploid hatched larvae revealed sperm DNA inactivation efficiency. The highest percentage of haploid putative gynogenotes 19.67 ± 4.19 % was obtained at UV irradiation dose 200 J/m2 with sperm diluted to 1:4.  相似文献   
9.
Comparative studies of ionic composition, osmolality, protein concentration and pH of seminal plasma along with spermatozoa concentrations were carried out in stellate sturgeon, Acipenser stellatus, and Russian sturgeon, Acipenser gueldenstaedtii. Analysis of A. gueldenstaedtii sperm showed significantly higher concentrations of Na+ (34.58 ± 4.61 mm ), Ca2+ (0.35 ± 0.12 mm ), Mg2+ (0.70 ± 0.25 mm ), Cl? (13.50 ± 4.04 mm ) and proteins (0.60 ± 0.29 mg/ml) in the seminal plasma than did seminal plasma of A. stellatus: Na+ (20.08 ± 10.75 mm ), Ca2+ (0.28 ± 0.06 mm ), Mg2+ (0.29 ± 0.05 mm ), Cl? (7.50 ± 3.00 mm ) and 0.30 ± 0.11 mg/ml proteins. Significantly higher concentration of K+ (5.42 ± 1.06 mm ) was observed in A. stellatus compared to A. gueldenstaedtii K+ (2.29 ± 0.50 mm ). Concentration of Na+ was positively correlated with osmolality (r = 0.819), levels of Cl? (r = 0.922) and Mg2+ (r = 0.727) and pH (r = 0.848). The concentration of Mg2+ was positively correlated with protein concentration (r = 0.774), Na+ (r = 0.727), Cl? (r = 0.872) and Ca2+ (r = 0.801). A positive relationship was also found between concentration of K+ and spermatozoa concentration (r = 0.709). Results revealed strong inter‐species differences in several parameters. The data should be useful for artificial fertilization and for cryopreservation of sturgeon sperm.  相似文献   
10.
The results of a 4-yr study focused on comparing growth performance in all-female and mixed-sex populations of common carp are presented. All-female and mixed-sex populations of purebred Northern mirror carp (M72) and scaly crossbreds of female Ropsha (ROP) and male/neomale M72 carp (ROP × M72) were used for this experiment. Average weight and survival after each growing season and slaughtering value after the third and fourth year of the study were measured. While after 8 wk of rearing no differences between all-female and mixed-sex populations were found, the 1-yr-old all-female mirror carp population (M72) gained 29.7% more weight ( P < 0.0001) than the mixed-sex (68.5:± 15.8 g against 52.8:± 13.9 g; meant S.D.) population. After the second, third and fourth year of rearing, live weight was 9.5% ( P = 0.0062) and 6.8% ( P = 0.0229) and insignificantly 5.1 % higher, respectively, in the all-female population. There was no significant difference, even after the fourth growing season, in live weight between all-females and bisexual scaly crossbreds (2,192 g± 478.3 and 2,206 g± 484.5, respectively). The percentage of the main edible parts (processed body, filleting yield) was significantly higher in both mirror and scaly, all-female populations at 3 yr of age but not significantly different in 4-yr-old fish. No distinct differences in survival and body shape of all-female and bisexual populations were found. The potential of all-female populations for commercial production is discussed.  相似文献   
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