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1.
Induced spawning in bream, Abramis brama (L), was studied using acetone-dried common carp pituitary (CP) and bream pituitary (BP) with or without the addition of human chorionic gonadotrophin (hCG). The total dose administered to fish was of 5.0 mg kg?1 BP or 4.0 mg kg?1 CP with or without 2000-2200 IU hCG kg?1 for females and 2.5 mg kg?1 BP or 2.0 mg kg?1 CP with or without 1000–1100 IU HCG kg?1 for males. In all male treated groups 100% of spermiation was observed: in females the most effective method was a triple injection with hCG and carp pituitary, resulting in 79% of females ovulated (over 68% of eyed eggs). Biological quality of eggs, expressed as a percentage of eyed eggs, was negatively correlated with time elapsing between resolving (final) injection and ovulation. Spawning success, expressed as a value of Se (spawning effectiveness coefficient), was higher in fish treated with triple injection.  相似文献   

2.
For the first time was characterized the semen of Pimelodus britskii, hormonally induced and non‐induced induced, during the reproductive period. The experiment 1 was conducted with 12 fish per month, divided into: (i) induced with Carp Pituitary Extract (CPE), and (ii) without hormonal induction (testes macerated). The experiment 2 was conducted, with 30 fish, divided into groups for comparison of different doses of CPE and human Chorionic Gonadotrophin (hCG; T1: control; T2: 3.0 mg kg?1 CPE; T3: 0.5 mg kg + 3.0 mg kg?1 CPE; T4: 0.5 mg kg?1 + 7.0 mg kg?1 CPE; T5: 200 UI kg?1 hCG), the same fish were used every month, and the semen was collected by abdominal massage. In both, experiments were assessed the sperm motility and velocity by means of the CASA software. In experiment 1, the concentration of spermatozoids was significantly increase by application of CPE compared untreated males. The volume and motility decreased gradually until the end of the experiment, the highest values were recorded for treatment induced (0.49 ± 0.25 mL and 62.18, respectively). The same occurred to Gonadosomatic Index, showing the smallest value at the end of the reproductive period. The fish from experiment 2 released reduced volume of watery semen (0.1 mL). The values of sperm concentration, motility velocity decreased gradually throughout the months. For P. britskii, the reproductive period influenced the production and sperm quality. Despite small seminal volume released the dose of 7.5 mg kg?1 of CPE proved effective.  相似文献   

3.
The aim of the present study was to study spawning stimulation in artificial reproduction of females pikeperch (Sander lucioperca L.) using “Chorulon” containing the human chorionic gonadotropin (hCG) and compare with “Supergestran” containing a mammalian GnRH ([D-Ala6]GnRHProNhet) analogue. The females were divided into eleven experimental groups and injected with hCG at 250, 500, 750, and 1 000 IU kg?1 body weight (BW) and mGnRHa at 1, 2.5, 5, 10, 25, and 50 μg kg?1 BW. In all treatments, a single intramuscular injection of hormone was performed. Control group was injected with 0.9 % NaCl, 0.9 cm3 kg?1 BW. The average percentages of ovulating females were 88.5 ± 12.3 and 80.8 ± 10.9 % in hCG- and mGnRHa-treated groups, respectively. The average diameter of eggs was 0.95 ± 0.06 and 0.98 ± 0.06 mm in hCG- and mGnRHa-treated groups, respectively. Neither ovulation rate nor diameter of egg was statistically differed among hormonally treated groups. Statistical difference was observed only in hatching rate, where the average were 73.6 ± 14.4 and 50.6 ± 17.7 % in hCG and mGnRHa-treated groups, respectively. Among hormonally treated groups, the best results were observed in groups treated with hCG at 500 and 750 IU kg?1 and in groups treated with mGnRHa at 25 μg kg?1. No ovulation was observed in the control group. This study indicated successful ovulation in pikeperch using a single intramuscular injection of hCG or mGnRHa analogue.  相似文献   

4.
Black sea bass Centropristis striata L. are protogynous hermaphrodites that develop and spawn as females before changing sex to male. Since all fish eventually become males, determining the relationship between sperm production, sperm quality and seasonal changes in plasma levels of testosterone (T) and 11‐ketotestosterone (11‐KT) could be useful for identifying appropriate males to maintain as broodstock. Milt and blood samples were collected three times during an 8‐week spawning season. Milt volume (3.5±0.76 mL kg?1), sperm density (3.2 × 108± 0.31 cells mL?1), sperm production [11 × 108±3.4 cells kg?1 body weight (BW)] and sperm motility (80±0.6%) were at their highest during the first sampling interval and coincided with the highest 11‐KT levels (1.0± 0.11 ng mL?1). All of the sperm indices decreased to their lowest levels during the final 3 weeks of the study. Sperm viability was highly correlated (adjusted R2=0.84) with sperm motility. Sperm cryopreserved in modified Mounib's extender (MME) had the highest post‐thaw motility compared with two other extenders. Post‐thaw motility of sperm cryopreserved in MME was not different from fresh after 90 days of storage. There was no difference in fertilization rates between fresh (69±2.4%) and post‐thaw (67±4.1%) sperm samples taken from the same male or among males. These results demonstrate that the quality of black sea bass spermatozoa is higher earlier in the spawning season and that acceptable post‐thaw fertilization rates can be obtained from cryopreserved sperm.  相似文献   

5.
A reliable breeding technique was developed for the mangrove red snapper, Lutjanus argentimaculatus (Forsskal 1775), to help sustain the aquaculture of this immensely popular species in Southeast Asia. Using standardized indices of female maturity (based on mean oocyte diameter of ≥0.40 mm), time of injection (1000–1130) and sex ratio (one female to two males), a single injection of 100 μg kg?1 luteinizing hormone‐releasing hormone analogue (LHRHa) (n=16 fish), but not 50 μg kg?1 (n=five fish), successfully induced egg (62.5% success rate) and larval (43.8%) production. Human chorionic gonadotropin (hCG) at 500 IU kg?1 (n=five fish) also failed to induce spawning, but doses of 1000 (n=22 fish) and 1500 IU kg?1 (n=15 fish) gave spawning (77.3% and 80.0% respectively) and hatching success rates (72.7% and 60.0% respectively) that were not significantly different from those of 100 μg kg?1 LHRHa. No spawning was observed in saline‐injected controls (n=seven fish). While mean spawning latency, egg diameter, egg production per spawn, percent egg viability, hatching rate, percent of normal larvae and cumulative survival of eggs to normal larvae did not differ significantly among the effective hormones and doses, 1000 IU kg?1 hCG had a higher percentage (76.5%) of total spawns with egg production per spawn in excess of one million than those of 1500 IU kg?1 hCG (50.0%) and 100 μg kg?1 LHRHa (40.0%). Mangrove red snapper spontaneously spawned from March–April to November–December with a peak of egg collection and spawning in May–June. Egg collection per spawn ranged from 0.05 to 6.35 million. Spontaneous spawning of mangrove red snapper exhibited lunar periodicity with spawns mostly occurring 3 days before or after the last quarter and new moon phases and occurred consistently between 02:00 and 04:00 hours. High fecundity and good egg quality, coupled with the ability to respond to induce spawning or natural spawning in captivity, provide a sound basis for improving the sustainability of red snapper aquaculture in Southeast Asia.  相似文献   

6.
Jundiá (Rhamdia quelen) is an important species for aquaculture in temperate and subtropical climates. In the present study, the results of different forms of GnRH analogue treatments on ovulation in jundiá have been compared with those from treatment with carp pituitary. Seven out of eight females ovulated in groups treated with carp pituitary (4.0 mg kg?1 BW) and Ovaprim (0.5 mL kg?1 BW). Injection with sGnRHa (10 μg kg?1 BW) combined with metoclopramide (20 mg kg?1 BW) caused a significantly lower rate of ovulation with three out of eight females responding. None of the fish injected with sGnRHa (10 μg kg?1 BW) alone ovulated. Mean PGSI [(weight of stripped egg mass/BW of the female before stripping) × 100] and mean fertilization rate values were high and similar between treatment groups. The obtained results indicate that in jundiá, there is a strong dopamine inhibitory tone on gonadotropin secretion. The gonadotropin releasing activity of sGnRHa can be potentiated by dopamine receptor antagonists and the combined treatment is effective in inducing ovulation. In this regard, domperidone proved to be more potent than metoclopramide.  相似文献   

7.
Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75?μg?kg?1 b.w. and compared with those males treated with 4?mg?kg?1 b.w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg?1 b.w., which contains dAla6-Pro9NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72?h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7?days after treatments in all hormonally treated groups. Spermiation rates were 100?% in the CPE and Ovopel groups and 25–50?% in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72?h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75?μg) groups compared to the CPE and GnRHa (25?μg) groups and decreased 72?h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75?μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75?μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor.  相似文献   

8.
This study determined the digestibility of protein in partially dehulled sunflower meal (SFM) and then, as the main goal, the nutritive value of high‐temperature extruded (≤149°C) partially dehulled SFM (SFMEX) for post‐smolt Atlantic salmon Salmo salar in sea water. The digestibility study was conducted using the settling column approach (‘Guelph system’) for faeces collection as described by Hajen, Higgs, Beames and Dosanjh. In the nutritive value study, triplicate groups of 50 salmon (mean weight ～116 g) in 4000‐L outdoor fibreglass tanks supplied with 25–40 L min?1, filtered, oxygenated (dissolved oxygen, 7.0–8.5 mg L?1), 11–12°C sea water (salinity, 29–31 g L?1), were fed twice daily to satiation one of five steam‐pelleted dry diets that contained 422 g of digestible protein (DP) kg?1 and ～16.4 MJ of digestible energy (DE) kg?1 on a dry weight basis for 84 days. Low‐temperature‐dried anchovy meal (LT‐AM) comprised 68.2% of the basal diet protein whereas in four test diets, SFMEX progressively replaced up to 33.0% of the DP provided by LT‐AM in the basal diet (SFMEX≤271 g kg?1 of dry matter). Sunflower meal had 87.9% DP. Diet treatment did not significantly affect specific growth rate (1.39–1.45% day?1), feed efficiency (1.19–1.26), percentage of dietary protein retained (45.8–47.5), gross energy utilization (46.5–49.4%), per cent survival (96.0–99.3) or terminal whole body and muscle proximate compositions. We conclude that SFMEX can comprise ≥271 g kg?1 of the dry diet or ≥22.7% of the digestible dietary protein of post‐smolt Atlantic salmon in seawater without any adverse effects on their performance.  相似文献   

9.
The experiment was designed to investigate the dietary factors that might enhance or interfere with astaxanthin (Ax) absorption in salmon including potentially interfering factors such as certain carotenoids (zeaxanthin and lutein), plant sterols, fibre and enhancing compounds such as cholesterol and vitamin E. Two hundred and eighty‐eight salmon (778 ± 78 g) were reared in sea water under controlled conditions and fed practical experimental diets. The experimental diets were supplemented with 40 mg Ax kg?1, in addition to various dietary factors, including cholesterol (2%), vitamin E (450 IU kg?1), wheat bran (5%), lutein (40 mg kg?1), zeaxanthin (40 mg kg?1) and phytosterol (2%). After 26 days of feeding, blood was collected and plasma was separated to determine the plasma Ax concentration. Ax was not detected in the plasma of fish fed the non‐pigmented diet. Fish fed diet containing 2% cholesterol significantly improved Ax absorption, which was reflected in the higher Ax concentration in plasma of Atlantic salmon. Other supplements including vitamin E, wheat bran, lutein, zeaxanthin and phytosterols in diet had no significant effect on plasma Ax concentration . Fish fed diet containing 2% cholesterol significantly increased cholesterol concentration in fish plasma. Phytosterol had no benefit to lower cholesterol plasma level in fish fed 2% phytosterol‐supplemented diet.  相似文献   

10.
The effects of a single injection of mammalian superactive analogue [d ‐Ser(tBu)6,Pro9‐NEt]‐LHRHa (20 μg/ kg?1) combined with the dopamine antagonist, haloperidol (HAL, 0.5 mg kg?1), for induction of ovulation in the koi carp broodstocks were determined under routine hatchery conditions. The results were compared with classic carp pituitary extract (CPE, double injection) application (water temperature 22 °C). Physiological saline (0.7% NaCl)‐injected fish were used as a control group and no ovulation occurred in this group. The spawning ratio was high in the LHRHa+HAL treatment group and in the CPE treatment group (6/7 and 5/7 respectively). The latency period was 14–16 h in the LHRHa+HAL treatment group and 12–14 h in the CPE treatment group (after the second injection). There was no difference between the two ovulating groups with respect to the spawning index (the weight of eggs as a percentage of female body weight) and fertilization rate of eggs (P>0.05). As a result, ovulation can be induced successfully in koi carp broodstocks with 20 μg kg?1 [d ‐Ser(tBu)6,Pro9‐NEt]‐LHRHa+0.5 mg kg?1 HAL treatment in a single injection without decreasing the egg quality. Application of this combination can be useful for hatchery and broodstock management in koi carp culture.  相似文献   

11.
This study assessed the suitability and cost efficacy of an equal blend of canola oil (CO) and poultry fat (PF) as a supplemental dietary lipid source for juvenile Atlantic salmon. Quadruplicate groups of Atlantic salmon (～400 g) held in 4000 L outdoor fibreglass tanks supplied with running (35–40 L min?1), aerated (dissolved oxygen, 7.88–10.4 mg L?1), ambient temperature (8.6–10.9°C) sea water (salinity, 26–35 g L?1) were fed twice daily to satiation one of three extruded dry pelleted diets of equivalent protein (488–493 g kg?1 dry matter) and lipid (267–274 g kg?1 dry matter) content for 84 days. The diets were identical in composition except for the supplemental lipid (234.7 g kg?1) source viz., 100% anchovy oil (AO; diet COPF‐0), 70.2% AO and 29.8% CO and PF (diet COPF‐30), and 40.3% AO and 59.7% CO and PF (diet COPF‐60). Atlantic salmon growth rate, feed intake, feed efficiency, protein and gross energy utilization, percent survival and whole body and fillet proximate compositions were not affected by diet treatment. Cost per kilogram weight gain was about 10% less for fish fed diet COPF‐60 than for diet COPF‐0. Percentages of saturated fatty acids in dietary and fillet lipids varied narrowly. Moreover, percentages of 18:1n‐9, monounsaturated fatty acids, 18:2n‐6, n‐6 fatty acids, 18:3n‐3, and ratios of n‐6 to n‐3 fatty acids in the flesh lipids were directly related to the dietary level of CO and PF whereas 22:6n‐3, the total of 20:5n‐3 (eicosapentaenoic acid; EPA) and 22:6n‐3 (docosahexaenoic acid; DHA), and n‐3 fatty acids revealed the opposite trend. Percentages of 22:6n‐3, EPA and DHA, and n‐3 fatty acids were significantly depressed in fish fed diet COPF‐60 versus diet COPF‐0. We conclude that a 1:1 blend of CO and PF is an excellent cost‐effective dietary source of supplemental lipid for Atlantic salmon in sea water.  相似文献   

12.
The brain of the pejerrey (Odontesthes bonariensis) has recently been shown to contain three forms of gonadotropin-releasing hormone (GnRH): salmon GnRH (sGnRH), chicken GnRH-II (cGnRH-II) and pejerrey GnRH (pjGnRH), nevertheless neuroanatomical studies on the distribution of these peptides are lacking. In this study we investigated the distribution of immunoreactive GnRH in the brain of adult pejerrey. Four different policlonal antisera and a monoclonal antibody against different GnRH variants were applied on cryosections and visualized using the ABC method. Three antisera (PBL#49, sGnRH#2 and cII741) revealed three different immunoreactive areas: the terminal nerve ganglion (at the junction between the olfactory bulbs and the anterior telencephalon), the preoptic area just anterior to the hypothalamus and the midbrain tegmentum. Fibers immunoreactive to GnRH were detected in different brain areas: the olfactory bulbs, the ventral thelencephalon, the hypothalamus, the mesencephalic area and an important innervation entering into the pituitary gland. Two other antibodies (LRH13 and s1668) labeled the two nuclei corresponding to the forebrain but not the midbrain tegmentum. As both antibodies have low crossreactivity to cGnRH-II, the data suggest that this group of cells express cGnRH-II. In summary, three different areas with immunoreactivity to GnRH were detected in the pejerrey brain. The distribution of sGnRH, pjGnRH and cGnRH-II expressing neurons, is discussed.  相似文献   

13.
Induced spawning in Eurasian perch, Perca fluviatilis L., was studied using human chorionic gonadotrophs (hCG) or acetone-dried common carp pituitary with or without hCG. The dose administered to fish was 5700 IU hCG kg-1 or 4.0 mg kg-1 carp pituitary with or without 500-700 IU hCG kg-1 for females and 2850 IU hCG kg-1 or 2.0 mg kg-1 carp pituitary with or without 250-350 IU hCG kg-1 for males. There were no statistically significant differences in quantity of milt in treated and control groups, although the best result was observed when males were treated with a triple injection of hCG and carp pituitary extract. Male spermiating success, expressed as a quantity of milt, was negatively correlated with fish weight. All females treated in this experiment had oocytes at the same division, so time of ovulation was highly synchronous. Spawning success, expressed as a spawning effectivity coefficient (Sc), was highest in fish treated with the triple injection. Spawning methods described in this paper were successful, even though hormones from another order of fish were used.  相似文献   

14.
Atlantic salmon were fed extruded diets based on either 100% fish oil (FO) or 100% vegetable oil blend (VO) substitution for 22 months. A total of seven distinct feeding periods were studied that incorporated higher levels of dietary oil inclusion, and larger pellet size as fish size increased. Whole fish levels of polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/F) and dioxin‐like PCBs (DLPCB) were analysed at the beginning and end of each of the seven feeding periods. The PCDD/F and DLPCB concentrations in the FO diets increased from 2.43 to 4.74 ng WHO‐TEQ kg?1 (TEQ, toxic equivalents), while VO diets decreased from 1.07 to 0.33 WHO‐TEQ kg?1 as oil inclusion increased. Partial least square regression analyses identified feed concentration, growth rate and feed utilization, but not variations in lipid content, as factors significantly affecting fish PCDD/F and DLPCB levels. Accumulation efficiencies for DLPCB (740 ± 90 g kg?1) were significantly (P < 0.01) higher than for PCDD/F (430 ± 60 g kg?1), explaining the increasing dominance of DLPCB levels over PCDD/F levels in whole fish (DLPCB : PCDD/F ratio of 2.4 ± 0.1 for both VO and FO fed fish) compared with feed (DLPCB : PCDD/F ratio of 1.5 and 0.34 for FO and VO feed respectively). Vegetable oil substitution significantly reduced the level of PCDD/F and DLPCB (eightfold and twelve‐fold, respectively) in the fillet of a 2 kg salmon, but, also negatively affected beneficial health components such as fillet n‐3/n‐6 fatty acid ratio.  相似文献   

15.
Camelina meal (Camelina sativa) (CM) is a potential protein source for aquaculture feeds, on account of its crude protein level (380 g kg?1) and inclusion of most indispensable amino acids. Two experiments were conducted with rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Rainbow trout (44.9 g fish?1) were fed diets with CM at 0 g kg?1 (0% CM), 70 g kg?1 (7% CM), 140 g kg?1 (14% CM) or 210 g kg?1 (21% CM) for 12 weeks at 14 °C in freshwater, and salmon (241.8 g fish?1) were fed diets with CM at 0 g kg?1 (0% CM), 80 g kg?1 (8% CM), 160 g kg?1 (16% CM) or 240 g kg?1 (24% CM) for 16 weeks at 14 °C in sea water. Growth, lipid and amino acid tissue compositions were compared between species. Trout could tolerate up to 14% CM diets without affecting the growth compared to the control, while salmon fed ≥8% CM gained less weight than the control (P = 0.008). The feed conversion ratio in trout fed 21% CM was higher than the control (P = 0.002), and feed intake in salmon fed ≥8% CM was lower than the control (P = 0.006). Trout fatty acid and amino acid composition showed minimal differences between CM‐fed and control‐fed fish, while salmon showed significant alterations after feeding CM diets. Multivariate analyses emphasized differences in tissue composition between species fed CM diets.  相似文献   

16.
Ovulation stimulation was carried out in carp (Cyprinus carpio L.) females of Lithuanian line B, using carp pituitary (0.3 + 2.7 mg kg?1), Aquaspawn (0.5 mL kg?1) and Aquaspawn + carp pituitary (0.3 mL kg?1 + 2.7 mg kg?1). The poorest results of reproduction (the lowest percentage of ovulating females, the lowest weight of eggs and their poorest quality) were obtained after double hypophysation. The best results were induced by the application of Aquaspawn alone. The effect of the applied stimulators was statistically non‐significant with respect to the weight of eggs, being highly significant (P ≤ 0.01) with respect to the percentage of fertilized eggs and that of living embryos after 24‐ and 36‐h incubation. The multiple‐regression equations were calculated for the three groups separately. The percentage of living embryos after 36‐h incubation constituted a dependent variable while the mass of females, the mass of eggs, the fertilization percentage and the percentage of living embryos after 24‐h incubation were independent variables. The regression was only significant (P ≤ 0.01) for the group of fish treated with Aquaspawn.  相似文献   

17.
Four distinct forms of native gonadotropin‐releasing hormone (GnRH) and two newly designed analogues were tested for their in vivo activity to induce ovulation in African catfish. The effects of these peptides on ovulatory parameters were compared with those of carp pituitary and [d ‐Ala6, Pro9‐NEt]‐mammalian GnRH analogue (mGnRHa), two tested ovulation‐inducing agents in African catfish. Assessment of ovulation was carried out by determining the ovulation ratio and the relative quantity of egg produced. From the results of the experiments, the order of potency of the native GnRH peptides is summarized as chicken GnRH‐II (cGnRH‐II) >salmon GnRH (sGnRH) >mammalian GnRH >chicken GnRH‐I (cGnRH‐I). Chicken GnRH‐II was as potent as mGnRHa while cGnRH‐I was totally ineffective. The new d ‐Orn6‐cGnRH‐II and d ‐Orn6‐sGnRH with a substitution at position 6 with d ‐isomer residue were as potent as the most extensively used mGnRHa, indicating that the position 6 modification might be more crucial than the substitution at the C‐terminal. On the basis of our results, the potential use and incorporation of cGnRH‐II and sGnRH for the development of more generic spawning induction therapies are suggested.  相似文献   

18.
A 75‐day experiment was conducted with juvenile gibel carp (Carassius auratus gibelio) (4.80 ± 0.01 g) to evaluate effects of dietary chitosan on fish growth performance, haematology, intestine morphology and immune response. Six isonitrogenous (crude protein: 383 g kg?1), isolipid (97.5 g kg?1) and isocaloric (gross energy: 16.7 kJ g?1) diets were formulated to contain 0, 1800, 4000, 7500, 10 000, 20 000 mg kg?1 chitosan, respectively. The results showed that the growth was depressed when the fish fed with 10 000 mg kg?1 chitosan. Serum cholesterol, triglyceride and low‐density lipoprotein decreased in 10 000 and 20 000 mg kg?1 chitosan. On day 75, blood leucocyte phagocytic activity respiratory burst and alternative pathway of complement haemolytic activity were enhanced in 4000 mg kg?1 chitosan. The number of goblet cell, intraepithelial lymphocyte of mid‐intestine and microvilli height of distal intestine increased at 4000 mg kg?1 dietary chitosan. Dietary chitosan modulated intestine microbiota, depressed pathogen bacteria Aeromonas veronii‐like and improved Cellulomonas hominis‐like, Bacillus oceanisediminis‐like and two uncultured bacterium‐like species on day 75. Dietary 7500 and 10 000 mg kg?1 chitosan enhanced the protection against Aeromonas hydrophila infection. In conclusion, oral administration of dietary 7500 mg kg?1 chitosan for 75 days is recommended for the survival of gibel carp.  相似文献   

19.
The effect of two commercial preparations containing different GnRH analogues with dopamine antagonists on quantitative and qualitative parameters of semen from chub Leuciscus cephalus L. collected in artificial conditions were examined. Semen was collected after the application of [(D‐Ala6, Pro9 NEt)‐mGnRH + metoclopramide] (Ovopel, n = 9), [(D‐Arg6, Pro9 Net)‐sGnR + domperidone] (Ovaprim, n = 9) and from the control group (0.9% NaCl, n = 9). Afterwards, semen volume, sperm concentration, total sperm production and semen pH were determined. Osmolality and pH of seminal plasma were also determined. Using the Computer‐assisted sperm analysis system (CASA), selected sperm parameters such as sperm motility (MOT %), progressively motile sperm (PRG, %), curvilinear velocity (VCL, μm s?1), straight‐line velocity (VSL, μm s?1), movement linearity (LIN, %), wobbling index (WOB, %), amplitude of lateral head displacement (ALH, μm) and beat cross frequency (BCF, Hz) were analysed. While Ovopel can also be used to stimulate chub spermation, the application of Ovaprim was much more effective for obtaining higher amounts of semen.  相似文献   

20.
The results of reproduction of females from Lithuanian strain B carp after ovulation stimulation with carp pituitary homogenate (CPH; 0.3+2.7 mg kg?1; group I), Ovopel (1/5+1 pellet kg?1; group II) or [d ‐Tle6, ProNHEt9] GnRH‐a (Lecirelin) with metoclopramide (15 μg kg?1+10 mg kg?1 respectively; group III) were investigated. The lowest percentage of spawning females (71%) was recorded in the group treated with CPH. In case of Ovopel or Lecirelin induced ovulation, 86% of females spawned. No statistically significant effect of the ovulation stimulator (group) on the weight of eggs was found; however, the highest mean weight of eggs (expressed both in grams and in the percentage of female body weight) was recorded for the group treated with Ovopel (1400 g and 13%). After the treatment with CPH or Lecirelin, the weight of eggs was 1140 g (11%) and 1100 g (10%) respectively. The ovulation stimulator significantly affected the percentage of live embryos after 36 and 48 h incubation of eggs (P≤0.05; P≤0.01). After treatment with [d ‐Tle6, ProNHEt9] GnRH‐a, eggs of the best quality were obtained and after 36 and 48 h incubation the mean percentages of live embryos were significantly higher than the means calculated for the remaining two groups. No statistically significant differences were found between the percentage of living embryos after 36 and 48 h incubation of groups I and II.  相似文献   

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