Female Broodstock Research Articles

Vertical Transmission and Early Diagnosis of the Microsporidian Enterocytozoon hepatonaei in Whiteleg Shrimp Penaeus vannamei

Microsporidia, which are ubiquitous obligate intracellular parasites responsible for a variety of diseases and economic losses in farming, have different transmission strategies. While horizontal transmission relies on sufucient parasite numbers released into environment, vertical transmission requires host reproduction to occur leading to a lower virulence, and also induces a sex ratio distortion. The second strategy has been reported in a broad range of hosts from protists to mammals, in which insects and amphipod crustaceans as the most common. The present study shows the first evidence of vertical transmission of a microsporidia in decapod crustaceans via an experimental description of the infection by Enterocytozoon hepatopenaei (EHP) in whiteleg shrimp Penaeus vannamei. The group of healthy shrimp was infected with EHP by feeding with infected-shrimp tissue and sharing habitat. The presence of EHP in the infected shrimps was detected by using Polymerase Chain Reaction (PCR) method with specific primers EHP-510F/EHP-510R and histopathological analysis. The Nauplius, Zoae 1 and Zoae 2 stages collected from the infected female broodstocks demonstrated that EHP can infect offspring from their parental shrimp, and interestingly EHP can be detected from Nauplius stage of shrimp by the use of PCR method.

Isolation and expression analysis of Bystin 1 transcript and protein during ovarian development of the giant tiger shrimp Penaeus monodon.

The full-length cDNA of bystin isoform 1 (PmBys1) of the giant tiger shrimp Penaeus monodon was characterized. It was 1553 bp in length containing an ORF of 1365 bp corresponding to a polypeptide of 454 amino acids. The level of PmBys1 mRNA in ovaries was greater than that in other tissues of females and in testes of males in both juveniles and wild broodstock (P < .05). In non-ablated wild female broodstock, PmBys1 mRNA significantly and progressively increased in ovaries from stage I of development, peaking at stage IV (P < .05). Its level in stages I-IV of eyestalk-ablated broodstock was greater than that in non-ablated broodstock (P < .05). Injection of exogenous serotonin (50 μg/g body weight) into 18-month-old shrimp resulted in a significantly increase of ovarian PmBys1 mRNA at 6-48 h post injection (hpi) (P < .05). PmBys1 protein (52 kDa) was found in ovarian stages I-V of non-ablated wild broodstock and II-IV of ablated wild broodstock, respectively. Along with the 52 kDa band, immunoreactive bands of 50 and 43 kDa were also observed in ovarian stages II-IV of both non-ablated and ablated broodstock and in ovaries of post-spawning broodstock. The 43 KDa band was not observed in ovarian stage I of wild female broodstock or in premature juveniles. PmBys1 protein was localized in the ooplasm of previtellogenic oocytes, nucleo-cytoplasmic compartments of vitellogenic oocytes and cortical rods of mature oocytes in wild broodstock. The results implied a possible role for PmBys1 during ovarian development in P. monodon.

Using of microsatellite DNA profiling to identify hatchery-reared seed and assess potential genetic risks associated with large-scale release of swimming crab Portunus trituberculatus in Panjin, China

Many economically important species in demand in the market and with depleted populations have been artificial bred and their seed intensively released into the wild. As one of the most important fishery species in China, the swimming crab Portunus trituberculatus has been stocked in Panjin at a large scale since 2012. Nevertheless, no genetic profile considering genetic effects of these practices has been constructed. The present study traced the crab population enhancement in Panjin. In 2015, a total of 1671 crabs were captured in Panjin and among them 120 individuals were identified as being hatchery-raised, indicating that hatchery-raised seed contributed to the local resource. To address possible genetic effects from the hatchery stock, we compared the genetic characteristic among female broodstock, recaptured hatchery-raised, recaptured non-hatchery-raised and a wild control population based on six microsatellite markers. Results showed obvious reductions in gene diversity and effective population size (Ne) and increased relatedness in recaptured hatchery-raised crabs. Moreover, recaptured non-hatchery-raised – the local population in Panjin – also exhibited similar patterns of dramatic loss of Ne and increased degree of relatedness. The genetic homogeneity involving low Wright's fixation index (Fst), large percentage genetic variance among individuals and strong gene flow appeared in all sample locations distributed in the Bohai Sea and the Yellow Sea. Our data suggest that large-scale stock enhancement of P. trituberculatus presents strong potential genetic risks to the Panjin local population and even the whole waters surrounding the Liaodong Peninsula. Several approaches were proposed to gain better insight into P. trituberculatus enhancement practices in the future.

The effects of L lysine in the diet of silver catfish (Rhamdia voulezi) female broodstocks

The objective of this study was to assess the L-lysine effect in silver catfish, Rhamdia voulezi female reproduction. Four hundred fish were used distributed in a random in 16 net cages (25 fish each × 4 replicates = 100 fish per treatment). The treatments consisted in four diets, isoproteic and isoenergetic (30% crude protein and 3,500 kcal kg -1 digestible energy) with different L-lysine levels: T1: 1.30; T2: 1.40; T3: 1.60 and T4: 1.95%. After 185 days of experiment 18 females per treatment were weighed, measured, and submitted to hormonal induction (0.5 and 5.0 mg kg -1 Carp Pituitary Extract). The females were then sacrificed and had their ovaries, liver and fat removed and the respective organosomatic indices were estimated. With regard to the reproductive parameters, the released oocytes, absolute fecundity and remaining ovaries were influenced ( P 0.05). We can conclude that L-lysine affects the reproductive parameters and accumulation of visceral fat in R. voulezi .

Skin Spotting Variation Associated with Biometric and Reproductive Parameters in Naturalized Populations of Rainbow Trout, Oncorhynchus mykiss, from Southern Chile

Background:Skin pigmentation in fish is involved in various biological processes. In salmonids, the interactions of skin spottiness with biometric and reproductive parameters are mostly unknown, especially in naturalized populations influenced by different ecological factors.Objective:To associate skin spottiness variation with biometric and reproductive parameters in broodstocks of naturalized rainbow trout populations from southern Chile.Method:The number of dark spots below the lateral line was assessed in male and female broodstocks of rainbow trout from two reproductive seasons, years 2007 and 2012, and then this dataset was associated with biometric and reproductive parameters of the same individuals, using multivariate data analysis in the form of stepwise forward multiple regression.Results:Male body weight from year 2007 had a significant negative influence on the number of dark spots below the lateral line (P&lt; 0.01), while the reproductive variables egg diameter and spawning time of females from years 2007 and 2012, respectively, had a significant positive influence on this parameter (P&lt; 0.01).Conclusion:Our results indicate that there are male biometric parameters with a significant negative influence on skin spottiness. Our data also reveal that some reproductive parameters have a positive influence on skin spottiness. The identification of these reproductive parameters related to spottiness variation would reflect the reproductive quality of female broodstocks living in natural environments.

Changes in immune parameters (lysozyme, IgM, C3) in early life stages and broodstock of Siberian sturgeon, Acipenser baerii

Abstract In the present study, lysozyme, immunoglobulin M (IgM), and complement component 3 (C3) were measured in unfertilized and fertilized eggs, two week post fertilization (WPF) larvae and 1, 2, 4, 6, and 12 month post fertilization (MPF) juveniles and the female broodstock of Siberian sturgeon, Acipenser baerii Brandt. The lysozyme level was measured with the turbidimetric method and IgM and C3 levels were measured with the ELISA method. The results showed that the lysozyme level decreased significantly from the unfertilized eggs to the 2-week-old larvae, and then it increased until 2 MPF. Significant changes in lysozyme levels were not observed from the 2 MPF juveniles to the broodstock. The IgM level decreased significantly from the unfertilized eggs to the 2 WPF larvae, then it increased until the 2 MPF, and, finally, it revealed a significant decrease in 4 MPF juveniles. Significant variations of C3 were found from the unfertilized eggs to the 2 MPF juveniles. Additionally, there were no significant variations in IgM or C3 in 4 to 12 MPF juveniles or in the female broodstock. The results indicate that two weeks post fertilization can be an immunologically sensitive period in early life stages of Siberian sturgeon.

CAROTENOID-ENRICHED DIET FOR PRE-MATURATION STAGE OF POND-REARED TIGER SHRIMP, Penaeus monodon PART I. THE EFFECTS ON GROWTH, PIGMENTATION AND WHOLE BODY NUTRIENT CONTENT

Carotenoids, besides as a natural pigment, may have vital roles in the growth of crustacean. The aim of this study was to clarify the influence of combined carotenoids given since pre-maturation stage on the growth performances, pigmentation and biochemical composition of the whole body of pond-reared tiger shrimp, Penaeus monodon. Two experimental diets were supplemented with or without carotenoid mixture consisting of astaxanthin, canthaxanthin and other carotenoids contained in Spirulina. The carotenoid mixture was supplemented in the commercial diet normally used as a starter feed for tiger shrimp, re-pelleted and fed to tiger shrimp with an initial body weight of 31.7±1.3 g. Shrimp were stocked in four 1,000 m2 concrete ponds with a density of 1 shrimp/m2 and fed until the shrimp reached maturation stage (broodstock size). Variables observed were growth performances and pigmentation properties during the pre-maturation stage and total carotenoid content in several tissues of the female broodstock after being fed with the diets until maturation stage. After 16 weeks, shrimp fed with carotenoid-enriched diet (PC) diet produced significantly (P&lt;0.05) higher biomass than the diet without the enrichment (PO). The color of raw shrimp fed with PC diet was darker with greenish-brown compared to shrimp fed PO diet which was greenish blue. The visual appearances of 3-min steamed shrimp produced the color of red-orange for shrimp fed carotenoid compared to orange-yellow for control PO. The total carotenoid content in the whole body of shrimp fed PC diet were significantly (P&lt;0.05) enhanced compared to control PO diet which was 42.8 ±5.8 and 55.8± 5.1 µg/g for PO and PC diet, respectively. Supplemental carotenoid in the pre-maturation diet increased the biomass production from 23.1±1.9 kg to 30.2 ±0.1 kg and enhanced the color of the shrimp which was in line with carotenoid content in the whole body of pond-reared tiger shrimp.

Effect of different maturation diets on reproductive performance of the broodstock of purple mangrove crab, Scylla tranquebarica

The present study was aimed at evaluating the reproductive performance of the broodstock of purple mangrove crab (Scylla tranquebarica) fed natural food and formulated diets supplemented with astaxanthin and/or DHA. Formulated diets were supplemented with 500 mg kg-1 of astaxanthin (FA), 10 g kg-1 of DHA (FD) and both astaxanthin and DHA (FA+D). Diet without astaxanthin and DHA (FCon) and natural food (NF) consisted of forage fish (Valamugil sp.), shrimp (Penaeid sp.) and mangrove clam (Polymesoda sp.) to serve as control. Female broodstock of initial body weight 129.07±17.03 g were stocked in HDPE tank and cultured under recirculating water system. Broodstock maturation was monitored until spawning. Reproductive performance of female and condition of the larvae were also evaluated. After 50 weeks, broodstock fed FA+D diet showed better maturation percentage, spawning rate, gonadosomatic index, oocytes diameter, molting, molt death syndrome and survival rate than FCon group (P0.05) to the FA+D group but diet FD resulted in better performance than FA. Broodstock fed FA+D diet had the highest hatching rate, number of larvae produced and significantly higher zoea II survival compared to FCon and NF groups (P

Production of artificial diets for female broodstock of western white shrimp (Litopenaeus vannamei) and study on their singular effect

Production of artificial diets for female broodstock of western white shrimp (Litopenaeus vannamei) and study on their singular effect

Spawning performance of Clarias gariepinus (Burchell, 1822) induced with ethanol preserved and fresh catfish pituitary extract.

This study was conducted to determine the efficacy of preserved and fresh pituitary extract of Clarias gariepinus (Burchell, 1822) to induced spawning in the same species. Growth performance of fry was also monitored for 15 days to determine the possible effect of natural hormone treatment on the fry. Pituitary glands (PG) were obtained from 12 male broodstocks, six extracted PG were preserved in 96% ethanol 24 h before injection, while the other were extracted and used in their fresh state. The PG solutions (1 g ml-1 of saline water) were injected at 1 ml kg-1 of the female broodstock. Ovaprim® (a synthetic hormone) was used as the control and administered at a rate of 0.5 ml kg -1 of fish. After a uniform latency period of 9 h 30 min, fish were striped, fertilized, incubated and the performance evaluated. Results obtained revealed better hatching performance using Ovaprim® synthetic hormone (64.52%), however, preserved PG gave better hatchability (59.74%) than fresh PG extract (51.39%). After 15 days of feeding ad libitum with shell-free Artemia cysts, the growth of fry spawn with preserved PG was comparable with that of the control, while least performance was observed using the fresh PG. It was concluded that preservation of PG in ethanol 24 h before injection had a positive effect on breeding performance and could be exploited in the commercial production of C. gariepinus fingerlings.

Establishment of monosex female production of sablefish (Anoplopoma fimbria) through direct and indirect sex control

Methods are needed for monosex production of sablefish (Anoplopoma fimbria) to capitalize on superior growth of females relative to males. This study aimed to characterize the system of sex determination and establish methods for both direct and indirect feminization of sablefish. Juvenile sablefish ~40mm fork length were fed diets containing 17β-estradiol (E2), 17α-methyltestosterone (MT), or ethanol vehicle alone (control) for 2months and then divided into subgroups either shifted to the control diet (E2- and MT-short (S) duration treatments) or maintained on steroid-treated diets for an additional 2months (E2- and MT-long (L) duration treatments). Fish were subsampled for gonadal histology at the midpoint and end of the dietary treatments and all remaining fish were individually tagged to monitor subsequent growth and gonadal development for 36months (post-treatment time points of 0, 4, 16, 24, and 36months). Control fish exhibited balanced (1:1) sex ratios. E2 treatment regardless of duration induced ovarian differentiation in 100% of the genotypic males (i.e., direct feminization), while only the MT-L treatment induced testicular differentiation in 100% of the genotypic females (i.e., generating “neomales”). A high proportion (89%) of MT-S genotypic females possessed intersex gonads, indicating short-term MT exposure was insufficient to induce complete sex reversal. Significant differences in sex-specific growth were apparent by 16months post-treatment and associated with gonadal phenotype; sablefish with ovaries outgrew those with testes, regardless of genotypic sex. Fish from the E2-S and -L and MT-L treatment groups maintained their respective feminized and masculinized states after steroid withdrawal, although MT-S treated genotypic females tended to show further masculinization post-treatment. Upon reaching sexual maturity, control males and neomales were crossed with wild-caught female broodstock. Resultant embryos from control crosses were 54.6±8.9% (mean±SD) genotypic female, while those from neomale-female crosses were 100±0.0% genotypic female. Following sex differentiation, gonadal histology demonstrated that offspring from control crosses had a balanced phenotypic sex ratio, whereas all neomale offspring developed normal ovaries. This study establishes that sablefish utilize an XX/XY system of sex determination and methods for both direct and indirect monosex female production.

Experimental vertical transmission of covert mortality nodavirus in Exopalaemon carinicauda.

Viral covert mortality disease (VCMD) has caused serious losses to shrimp aquaculture in China in recent years and the ridgetail white prawn Exopalaemon carinicauda has been suspected to be one important factor in perpetuating the high prevalence of covert mortality nodavirus (CMNV) infections due to its perennial presence in shrimp farming ponds and water from natural habitats. Experiments were carried out to determine the possibility of vertical transmission of CMNV in E. carinicauda in this study. CMNV infection in gonads, fertilized eggs and larvae was investigated by using the methods of reverse transcription nested PCR (nRT-PCR), in situ hybrization (ISH) and transmission electron microscopy (TEM). The ovarian tissue and testis tissue of artificially infected parental E. carinicauda were proved to be CMNV-positive by nRT-PCR. Fertilized eggs were also found to be CMNV-positive by nRT-PCR whether the fertilized eggs originated from the CMNV-positive female broodstock mated with the CMNV-negative male broodstock, or they originated from the CMNV-negative female broodstock mated with the CMNV-positive males. The results of ISH indicated that the positive signals were evident in the oocytes within ovarian tissue and nauplii. By TEM analysis, CMNV virions were observed in oogonia, oocytes, spermatocytes, fertilized eggs and nauplii. The presence of CMNV in fertilized eggs and larvae indicates that CMNV can transmit vertically via sperm and oocytes in E. carinicauda, which highlights the high probability of vertical transmission of CMNV in the main species of cultured shrimp and prawns.

N-3 Long-chain polyunsaturated fatty acids improve the sperm, egg, and offspring quality of Siberian sturgeon (Acipenser baerii)

Two diets with the same docosahexaenoic acid:eicosapentaenoic acid ratio (1.8:1), but with different n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) contents [29.5g/kg (DH) and 17.9g/kg (DL)], were designed and fed to two groups of 46 female and 30 male Siberian sturgeon (Acipenser baerii) broodstock for 11months. Sperm and egg quality and reproductive performance indices were recorded during cross-breeding. Larval offspring resulting from cross-matings were divided into the following four groups for a 30-d feeding trial: D1 (DH♀×DH♂), D2 (DH♀×DL♂), D3 (DL♀×DH♂), and D4 (DL♀×DL♂). The results showed that egg size of the DH group was significantly larger than that of the DL group. With respect to sperm quality, there were no significant differences in wobble, amplitude of lateral head displacement, beat/cross frequency, and mean angular displacement between the two dietary groups; however, a high n-3 LC-PUFA diet increased sperm curvilinear, straight-line, and average path velocities in the DH group. The DH group had significantly lower levels of serum triglyceride, low-density lipoprotein cholesterol, and malonaldehyde, but higher superoxide dismutase level, and total antioxidant capacity compared with the DL group. At 7 and 32days post hatching, the survival of larvae in groups D1 and D2 was significantly higher than that in groups D3 and D4. The specific growth rate of larvae in group D4 was the lowest among the four groups. The results suggest that n-3 LC-PUFA can improve the reproductive performance of male and female broodstock of Siberian sturgeon and the quality of their offspring, but that n-3 LC-PUFA enrichment of the diet is more critical for female broodstock than for males.

Effects of Catfish (Clarias gariepinus) Brood-stocks Egg Combination on Hatchability and Survival of Fish Larvae

Fish seed production of catfish and tilapia has been successfully carried out in Nigeria. Despite the success, there still exist a wide gap between fish seed demand and supply, this therefore necessitate increased research for development. This project is aimed to study the effects of Clarias gariepinus brood-stocks’ egg combination on hatchability and survival of fish larvae. 2 females gravid Clarias gariepinus brood stock size (800-900 g) were injected with pituitary gland hormone at 3 mg kg-1 of body weight. Milt gotten from the selected male was mixed with collected eggs of injected females after the expiration of latency period. 1/3 of the eggs collected from T1 (first female brood stock) and T2 (second female brood stock) were combined and recorded as T3 (mixture of 1/3 of T1 and T2). Each of T1, T2 and T3 were replicated as T11, T12, T13, T21, T22, T23, T31, T32, T33. Each of the replicated fertilized egg was spread in a monolayer pattern on a 1 mm diameter net in nine 0.8 m × 0.8 m × 0.8 m aquarium tank under a recirculatory system. Water quality, fecundity, fertilization rate and survivability of fish were determined. The data collected were analyzed using analysis of variance (ANOVA) at p < 0.05 significant level. The percentage fertilization was 62.34a, 61.98a and 62.75a for T1, T2 and T3 respectively. The percentage hatchability was 52.11a, 50.32a and 51.51a for T1, T2 and T3 respectively. The survivability result shows relatively high survival rate in treatment T1 and T2, while the rate of survival in T3 was very low. Egg combination does not have effect on fertilization rate and hatchability of eggs; however, it reduces the survival of larvae. In order to increase survival of catfish fry, it is important to avoid mixture of eggs from multiple brood fish.

A comparative study on growth and gonadal development of Litopenaeus vannamei broodstock fed different formulated feeds

PDF HTML阅读 XML下载 导出引用 引用提醒 饲料中添加南极磷虾粉对凡纳滨对虾亲虾生长、性腺发育及脂肪酸积累的影响 DOI: 作者: 作者单位: 1. 中国海洋大学 海洋生命学院, 山东 青岛 266003;2. 中国水产科学研究院 黄海水产研究所 农业部海洋渔业资源可持续利用重点开放实验室, 山东 青岛 266071;3. 青岛海洋科学与技术国家实验室 海洋渔业科学与食物产出过程功能实验室, 山东 青岛 266071 作者简介: 张玉玲(1992-),女,硕士研究生,研究方向为水产动物营养及育种.E-mail:chenxiyuling@126.com 通讯作者: 中图分类号: S96 基金项目: 国家自然科学基金面上项目（31572616）；中国水产科学研究院基本科研业务费项目（20603022016006）. A comparative study on growth and gonadal development of Litopenaeus vannamei broodstock fed different formulated feeds Author: Affiliation: 1. College of Marine Life, Ocean University of China, Qingdao 266003, China;2. Key Laboratory for Sustainable Utilization of Marine Fisheries Resources, Ministry of Agriculture;Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China;3. Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为探讨人工配合饲料中添加磷虾粉对凡纳滨对虾（）亲虾性腺发育的影响，分别在饲料中添加0、10%、20%的南极磷虾粉，配制3组人工配合饲料（饲料组1、饲料组2和饲料组3）对12月龄的凡纳滨对虾进行了为期60 d的营养强化培养，并以投喂双齿围沙蚕（）为对照组。营养强化结束之后，比较分析了不同饲料组凡纳滨对虾亲虾的体重增重率、肝胰腺指数（HPI）和性腺指数（GSI）；另外，检测分析了各组饲料以及亲虾性腺和肝胰腺的脂肪酸组成。结果表明，对照组的雌雄亲虾体重增重率均高于3个饲料组；饲料组2的HPI最低，为（2.37±0.02）%，与对照组无显著差异（P<0.05）。同时，本研究还比较分析了饲料脂肪酸组成与亲虾性腺、肝胰腺脂肪酸组成的相关性以及对亲虾性腺发育的影响。结果显示，饲料中添加一定含量（10%~20%）的南极磷虾粉可在一定程度上成为凡纳滨对虾亲虾营养强化阶段的优良饲料。 Abstract:This experiment was conducted to evaluate different artificially formulated feeds on promoting gonadal development in broodstock during the nutrient enrichment stage. Three kinds of formulated feeds, numbered diets no.1 (without krill meal), no.2 (10% krill meal), and no.3 (20% krill meal) were used as the experimental groups, with two replicates, and natural polychaete worm bait was used as the control group. The purpose of the experiment was to determine the appropriate formulated feed to enhance gonadal development in broodstock. The four treatment groups were fed the four different feeds for 60 d, and whole-body, hepatopancreatic, and gonad weights were determined. In addition, the fatty acid profiles of the four feeds and those of the hepatopancreas and gonads were analyzed in the four treatment groups. Fatty acid profiles of feed are important for gonadal development and reproduction in brood stock, as they can affect the hepatopancreatic and gonadal fatty acid profiles, as well as gonadal development. Eicosapentaenoic acid (EPA) docosahexaenoic acid (DHA), and arachidonic acid (AA) are three kinds of polyunsaturated fatty acids (PUFAs) that play significant roles in gonadal development. T he results showed that female broodstock in the control group had the significantly highest weight gain rate, which was (78.10±6.38)% (<0.05), compared with that of the others. No difference in weight gain rate (>0.05) was observed between female broodstock in the three formulated feed groups. Weight gain rate of male broodstock was lower than that of females. Males in the control group had the highest weight gain rate, but no difference (>0.05) was observed between males fed diets no. 3 and no. 2. Fish fed diet no.2 had the lowest hepatopancreatic index at (2.37±0.02)%; the hepatopancreatic index was not different (>0.05) from that in the control group, but was significantly different (<0.05) from that in the other two treatment groups. Fish fed diet no. 2 had a significantly higher (<0.05) gonadosomatic index (GSI) than that in the other groups, but no difference (>0.05) in GSI was observed between fish fed diet no.3 and the control group. The fatty acid profiles differed among the four feeds. More ∑PUFA was detected in than those in the artificially formulated feeds, and EPA, DHA, and AA contents in were higher than those in the formulated feeds. Diet nos. 2 and 3 had significantly more (>0.05) ∑PUFA as well as more EPA, DHA, and AA than those in diet no.1, indicating that the fatty acid profiles in diet nos. 2 and 3 were closer to those in . These results show that the fatty acid profiles in gonads were correlated with the fatty acid profiles in the brood stock feeds. 参考文献 相似文献 引证文献

PROFILE OF GONAD DEVELOPMENT AND SPAWN MILKFISH BOODSTOCK, Chanos chanos Forskall G-1 WITH HORMONE IMPLANT IN THE CONTROLE TANK

This research was conducted in Institute for Mariculture Research and Development (IMRAD) using on concrete tanks 150 m³. The objective of this research was to know the performance and gonad maturations development and spawn activities of first generation (G-1) broodstock from individual selection. The experiment test of milkfish broodstock with weight size of 3,891.67±344.99 g were reared on tank. Fish were reared at initial density of 60 individuals fish in 150 m³ concrete tanks. The treatments were: with hormone (A) and without hormone (B) implantation. The doze of LHRH-a implant hormone was 50 µg/kg. The broodstock were reared using of standard procedure operational (SOP) for spawning and gonad maturations. The result of the experiment showed that fish with hormone implantation gave the better results in gonad development on stage of reproduction than fish without hormon implantation. The gonad maturations and development on male and female broodstock diameter of oocyte and sperm were 450 µm and positive 2 and 3, respectively. The broodstock was spawn on the continue rear culture in the tank. The frequency of spawning were 8 times (with hormone) and 4 times (without hormone implantation) with total number of egg was 1,660,000 and 500,000 pc, respectively. The quality of eggs were 55-95% for fertilities and index activity survival (SAI) after hatching larvae was 4-5 days.

Neuropeptide F stimulates ovarian development and spawning in the female giant freshwater prawn, Macrobrachium rosenbergii, and its expression in the ovary during ovarian maturation cycle

Neuropeptide F (NPF) plays important roles in the regulation of a variety of physiological processes, including stimulation of food intake. At present, there is a current lack of basic knowledge regarding the effect of NPF in the control of female crustacean reproduction. In this study, we investigated expression of NPF in ovaries of female Macrobrachium rosenbergii (Mr) during ovarian development cycle, and its effects on ovarian maturation and spawning. MrNPF-immunoreactivity (-ir) was detected in the ovaries and its levels fluctuated during the ovarian maturation cycle: MrNPF-ir was more intense in the early- and mid-stages of ovarian development, and suddenly decreased in the mature stages. By RT-PCR, MrNPF transcript levels also increased during the early- and middle stages of ovarian development, and suddenly fell at late stage. The prawns were treated with varied doses of MrNPF and the effects were investigated by assessing the ovarian maturation period, oocyte diameter (OD), gonado-somatic index (GSI), and hemolymph vitellogenin (Vg) concentration. MrNPF-treated prawns showed significantly decreased ovarian maturation periods, and increased GSI, OD, and Vg levels compared with those of control groups. MrNPF also caused significantly earlier spawning compared with the control groups, while the mean fecundity between MrNPF-treated prawns and controls did not differ significantly. However, the numbers of eggs per spawn among experimental groups were higher compared with those of the controls. This work provides a novel and useful basic knowledge of NPF on female reproduction in crustaceans, and its possible use in aquaculture for accelerating and enhancing reproduction of the female prawns. Statement of relevanceAlternative techniques to eyestalk ablation to stimulate ovarian maturation in captive prawn broodstock are needed in order to avoid cruel practice on cultured prawns. Attempts have been made in using neurohormones, including neuropeptides to prime female broodstocks to stimulate growth and reproduction to replace the eyestalk ablation. NPF is a neuropeptide known for its control of feeding; however, there is currently no report on the role of NPF in female M. rosenbergii reproduction. We are the first to report the effects of NPF on ovarian maturation and spawning, and its expression and fluctuation in ovaries during the ovarian cycle in the female decapod crustacean. Our findings are novel and the data obtained could be useful for accelerating and enhancing reproduction of the female freshwater prawns.

Vertebrate-Type Steroid Profile in Different Tissues of Wild and Endocrinologically Manipulated Female Brood Stocks of &lt;i&gt;Penaeus monodon&lt;/i&gt;

The endocrine mechanism regulating reproduction of tiger shrimp, Penaeus monodon , is a field of topical interest, which is to be addressed in detail as control of reproduction in captivity is conditional for domestication. In this study, the titres of estradiol and progesterone in hemolymph, ovary and hepatopancreas during various reproductive phases of females were quantified using ELISA. Circulating concentration of hemolymph estradiol and progesterone in the endocrinologically-induced (eyestalk ablated) females was also quantified. Additionally, the evidence for estradiol and progesterone receptors was provided using immunohistochemistry. Levels of progesterone in hemolymph and ovary were highest in the vitellogenic and ripe phases (P > 0.05). Conversely, in hepatopancreas significantly higher progesterone level was detected at immature phase (184.3 ± 2.3 pg/ml). Estradiol was highest in hemolymph (65.97 ± 0.8 pg/ml) and ovary (58.47 ± 0.7 pg/ml) at the early vitellogenic phase. In hepatopancreas, however, lowest level of estradiol was detected at the early vitellogenic phase (121 ± 0.38 pg/ml). Progesterone and estradiol receptor protein signals were predominantly found in the pre vitellogenic oocytes. These results suggest the possible involvement of vertebrate-type steroid in the reproductive maturation of P. monodon .

A study on incubation of Brown Trout (Salmo trutta sp.) eggs and feeding of fry

In this study, spawning, incubation success or survival rate of brown trout and initial feeding of fry were investigated. The wild broodstock in this study were caught in Akcay river in Sapanca. In July 2008, 7 female and 1 male fish with a body weight between 300-350 g were brought to the Istanbul University, Faculty of Fisheries Sapanca Inland Waters Research Center (Adapazari, Turkey). These fish were kept in fiberglass adaptation tanks and were fed fresh rainbow trout meat. During this period, fish were fed with 9 mm pelleted feed. In June 2009, when fish had reached an average weight of 2500-3000 g, the first biometric measurements on the fish were performed. In early March 2010, about 3000 eggs were stripped from one female broodstock and sperms from the male brown trout. After the fertilization, the eggs were placed in horizontal incubators. The eye development started on the 21st day and hatching began on the 30th day. Hatching was found to be approximately 74%. When fish run out of their yolk sac, fry were divided into three groups of 600 individuals per tank and kept under same incubation conditions. Fry were fed feeds such as Artemia sp., fresh lamb liver, microdiets (300, 500 and 700µm) and extruded pellet feed (1mm). For the first group, fry were started on Artemia for seven weeks and continued on microdiets and extruded pelleted feed. For the second group, fry were started on microdiets and continued on extruded pellet feed. For the third group, fry were started on fresh lamp liver for a month and continued as the other groups. Fry were fed multiple times a day to satiation. Water used in the experimental tanks was from the research center. Average parameters recorded included water temperature of 11.5oC, pH of 7.86 and DO of 9.6 mg/L. At the end of the experimental period, the number of dead fry were 77, 104 and 123 in the first, second and third groups respectively. In conclusion, the present study indicated that the first generation eggs incubation from wild broodstock brown trout adapted to culture conditions successfully. However, further studies on the first feeding at the fry stage are encouraged. Keywords: Brown trout, broodstock culture, egg incubation, survival, fry nutrition

Biofloc technology application in African catfish fingerling production: The effects on the reproductive performance of broodstock and the quality of eggs and larvae

The present study evaluated the effects of biofloc technology (BFT) application on African catfish (Clarias gariepinus) fingerling production with more focus given to the reproductive performance of broodstock and the quality of eggs and larvae. For broodstock experiment, two broodstock culture systems were compared, i.e. biofloc and control systems. In biofloc systems, regular additions of organic carbon source (molasses, C/N ratio of 10) were conducted to stimulate the growth of heterotrophic microbial biomass as the main constituent of biofloc, whereas no molasses was added to the control systems. Young female broodstock with a mean body weight of 657±0g were maintained in three replicate outdoor tanks (2.5×2.0×0.8m) per treatment at a density of 5fish/m2, whereas male fish were maintained in two replicate tanks per treatment at a density of 4fish/m2. The larvae produced by the broodstocks in both systems were subsequently assessed by larval starvation tolerance test and growth test. The gonadosomatic index (GSI) and fecundity of female broodstocks in both treatments were generally comparable, except on day-122 when the relative fecundity of biofloc broodstock was 26% higher than that of the control (P<0.05). Interestingly, the embryonic development rate of eggs produced by biofloc broodstocks was higher than that of the control (P<0.05). The survival in starvation tolerance test and growth tests was notably improved in the larvae produced by biofloc broodstocks. Furthermore maintaining the larvae in biofloc systems could also enhance the fish survival and final body length. Statement of relevanceThis study demonstrates a novel research on the application of biofloc technology in broodstock and larval rearing of African catfish. Housing African catfish broodstock in biofloc systems significantly affected the embryonic development rate and the larval quality. Improvements in survival and growth were observed in the larvae housed in biofloc systems.