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1.
Xiaohua Xia Jie Zhao Qiyan Du Jinhua Zhi Zhongjie Chang 《Fish physiology and biochemistry》2011,37(1):53-59
Paramisgurnus dabryanus (Cypriniformes; Cobitidae), has been an emerging aquaculture species in China since the 1990s. In this study, random amplified
polymorphic DNA fingerprinting with 220 primers was used to identify a sex-specific DNA marker in pooled DNA and individual
DNA samples from male and female P. dabryanus. One primer, S2115, produced a novel sex-specific DNA fragment found only in tested females. This female-specific fragment
was 917 bp with 36% GC content, and was named Pdff1. To further validate the authenticity of this female-specific marker for
sexing, two PCR primers (pdff1-F and -R) were designed according to the cloned female-specific sequence. Amplification showed
bands specific for females. Dot blot and Southern blot hybridization experiments both displayed female specificity using this
marker as the probe. Two other P. dabryanus populations were tested by dot blot hybridization with the Pdff1 probe. The hybridization signals were seen in 33 or 43%
of males in addition to all females in the Jinan and Xichuan populations, respectively. We propose to use this sex-specific
marker to rapidly and specifically identify the gender of P. dabryanus from the ancient Yellow River Wetland in Yanjin, Henan Province. Our results could assist in cloning sex-specific chromosomal
regions. 相似文献
2.
Xiaoyun Zhou Khalid Abbas Mingyun Li Libao Fang Su Li Weimin Wang 《Aquaculture International》2010,18(3):349-359
To determine the cytotype with better traits for the aquaculture practices of the dojo loach Misgurnus anguillicaudatus from the viewpoint of fish farming improvement, factorial crosses (2n♀ × 2n♂, 2n♀ × 4n♂, 4n♀ × 2n♂, 4n♀ × 4n♂) were conducted
between natural diploids (D) and tetraploids (T), producing DD, DT, TD, and TT groups (female listed first). The potential
benefits of the different cytotypes in culture were evaluated by comparing growth performance and survival rate for a 15-month
rearing trial under the same production conditions. The average fertilization rate in DT and TT was significantly lower than
in the DD and TD groups, possibly indicating the poor fertilizing capacity of the tetraploid sires. Survival rate in DT and
TD was slightly lower than in DD but significantly higher than in the TT groups. Tetraploid females produced obviously larger
eggs than diploids and, subsequently, significantly longer initial body length of TT and TD than DD and DT fry. However, from
the second month of the growth trial, TT suffered higher mortality than other cytotypes, which significantly influenced morphometric
growth parameters. The TD group exhibited superior growth performance throughout the experiment. The mean body length of DT
was comparable with that of DD fish during the first 7 months but began to outgrow DD from the 9th month. This study suggests
that the relatively better growth of tetraploid and higher survival rate of diploid can be integrated via inter-ploidy hybridization
to get TD triploids with better culture traits. 相似文献
3.
Haematological and serum biochemistry parameters were studied and compared between cultured and wild ecotypes of Dojo loach
Misgurnus anguillicaudatus during the prime fishing season, i.e. May–August. Data were analysed for the impact of feeding regime and other ecological
conditions on the physiology of fish. The results revealed that haemoglobin, cholesterol, total protein, creatinine and uric
acid levels in the two ecotypes were significantly different (n = 56, df = 54, P < 0.05). In addition, red blood cell, glucose, triglyceride and urea nitrogen levels were significantly higher in cultured
individuals (n = 56, df = 54, P < 0.01) than in their wild counterparts. In contrast, the white blood cell level in cultured fish was significantly (n = 56, df = 54, P < 0.01) lower than that in the wild ones. These differences can be attributed to the physiological acclimatization of the
fish to their living conditions and feeding regime, which influences the energy metabolism and, consequently, the health of
the fish. 相似文献
4.
Huayu Song Mengxun Wang Zhongkai Wang Haiyang Yu Zhigang Wang Quanqi Zhang 《Fish physiology and biochemistry》2016,42(4):1073-1092
5.
The immediate-early gene (egr-1) expression was used to examine the neuron’s response in telencephalon of goldfish during spatial learning in small space.
Fishes were pre-exposed in the experimental apparatus and trained to pick food from the tray in a rectangular-shaped arena.
The apparatus was divided into identical compartments comprising three gates to provide different spatial tasks. After the
fish learned to pass through the gate one, two more gates were introduced one by one. Fish made more number of attempts and
took longer time (P < 0.05) to pass through the first gate than the gate two or three. This active learning induces the expression of egr-1 in telencephalon as established by western blot analysis. Subsequently, the fish learn quickly to cross the similar type
of second and third gate and make fewer errors with a corresponding decline in the level of egr-1 expression. As the fish learned to pass through all the three gates, third gate was replaced by modified gate three. Interestingly,
the level of egr-1 expression increased again, when the fish exhibit a high exploratory behavior to cross the modified gate three. The present
study shows that egr-1 expression is induced in the telencephalon of goldfish while intensively acquiring geometric spatial information to pass
through the gates. 相似文献
6.
Jian-He Xu Feng You Wei Sun Bin-Lun Yan Pei-Jun Zhang Bi-Xiang Jing 《Aquaculture International》2008,16(6):623-634
Turbot Scophthalmus maximus exhibits sexually dimorphic growth, with females growing faster and reaching larger adult sizes than males. Thus, development
of techniques for preferentially producing females is necessary to optimize production of these species. In this paper, gynogenetic
diploids of turbot were induced by activating egg development with ultraviolet (UV)-irradiated left-eyed flounder Paralichthys olivaceus sperm combined with cold shock to prevent extrusion of the second polar body. The results of UV irradiation experiments showed
that survival, motility, and duration of activity of P. olivaceus sperm generally decreased with increase in UV dose. The typical Hertwig’s effect was observed after fertilized turbot eggs
with UV-irradiated P. olivaceus sperm and the optimal UV dose for gynogenetic haploid production was 36,000 erg mm−2. At 15°C, appropriate timing of cold shock for retention of the second polar body in turbot eggs was at 6 min after fertilization.
Results of different combinations of two shock temperatures (1 or 3°C) and four shock durations (15, 25, 35 or 45 min) at
6 min after fertilization demonstrated that shock of 25 min at 1°C gave the highest production of diploid gynogens (39.58%
relative to its diploid control). The results of this study reveal that the use of UV-irradiated P. olivaceus sperm for activation of turbot eggs and cold shock for polar body retention is an effective method to produce gynogenetic
offspring. 相似文献
7.
8.
The ability of an algicidal bacterium Marinobacter salsuginis strain BS2, isolated from shrimp pond water, to reduce shrimp mortality was investigated under laboratory conditions. When
two species of shrimp (Penaeus monodon and Litopenaeus vannamei) (body length 1.5–1.8 cm) were cultured together with the dinoflagellate Noctiluca scintillans, nearly 80 % of the shrimps died within 7 days. However, when bacterial strain BS2 was also added to the culture, N. scintillans was killed within 48 h, and shrimp survival rates on the 7th day improved from 23 to 87 % for both P. monodon and L. vannamei. The bacterium BS2 alone had no effect on shrimp condition. Under conditions of increased dissolved oxygen, the effect of
using BS2 was greater, and shrimp survival rates improved even more dramatically, from 26 to 98 %. These studies provide the
first evidence that the use of killing bacteria, isolated from shrimp culture water, can suppress harmful algal blooms (HABs)
and thus restore the efficiency of shrimp production. The control of HABs in this way in shrimp culture farms would be a major
benefit for shrimp production. 相似文献
9.
Youji Wang Menghong Hu Weimin Wang S. G. Cheung P. K. S. Shin Ling Cao 《Aquaculture International》2010,18(2):135-148
The effects of delayed first feeding on growth and survival and starvation on the point-of-no-return of loach Misgurnus anguillicaudatus larvae were studied by evaluating morphometric characteristics under controlled conditions. Larvae began to feed exogenously
at 3 days after hatching (DAH) and the PNR occurred between 9 and 10 DAH at 23 ± 1.0°C. The experimental design included a
conventional feeding regime with initial feeding from 3 DAH as a control, delayed first feeding for 4, 5 and 6 DAH. Morphometric
characteristics (head depth, body depth, eye diameter, mouth diameter, musculature height, total length and yolk sac volume)
were evaluated under different initial feeding time (3, 4, 5 and 6 days after hatching). Loach larvae initiated first feeding
at 4, 5 and 6 days after hatching achieved comparatively lesser growth performance in all morphometric characteristics than
that of 3 days at the end of the experiment. By day 6, significant differences were observed between 3 and 6 days initial
feeding larvae for all morphometric characteristics except eye diameter and mouth diameter. Similarly, significant differences
were noticed between 3 and 5 days initial feeding. However, there were no significant differences in head depth, body depth,
eye diameter, mouth diameter, and total length between 3 and 4 days initial feeding until 12 DAH. After 15 days rearing, significant
differences in all morphometric characteristics appeared between 3 and 4 days initial feeding and followed to the end of the
experiment. It was also observed that the yolk absorption in loach larvae was completed by 6 days irrespective of the differences
in the initial feeding. The yolk volume of 4 and 5 DAH larvae initiated first feeding at 3 days (0.0125 ± 0.0015; 0.0077 ± 0.0009 mm3) had significant differences compared with yolk volume of larvae initiated first feeding at 4 days (0.0081 ± 0.0011; 0.0039 ± 0.0004 mm3), 5 days (0.0079 ± 0.0010; 0.0017 ± 0.0002 mm3) and 6 days (0.0082 ± 0.0011; 0.0016 ± 0.0001 mm3). Survival rates of four treatments were estimated daily for 30 days and significant differences were observed between the
treatments at the end of the experiment. The final survival rate was higher when the loach larvae initiated feeding at 3 days
(75.9%) when compared with 4 days (31.8%), 5 days (14.5%) and 6 days (6.4%). The present study suggests that the first feeding
of loach larvae should be initiated at 3 DAH for achieving better growth and survival or else bad growth performance will
engender if the first feeding is delayed. 相似文献
10.
Takafumi Fujimoto Aya Yamada Yukihiro Kodo Kohei Nakaya Michiko Okubo-Murata Taiju Saito Kazuto Ninomiya Michiko Inaba Masamichi Kuroda Katsutoshi Arai Masaru Murakami 《Fisheries Science》2017,83(5):743-756
Repetitive DNA sequences, ManDra and ManBgl, were isolated from the DraI and BglII digests of the genomic DNA of Misgurnus anguillicaudatus, respectively. A primer set of ManDra distinguished two genetically different groups (A and B) of M. anguillicaudatus by specific electrophoretograms. A primer set of ManBgl amplified the DNA of M. anguillicaudatus and M. mizolepis. The individuals of M. anguillicaudatus were divided into two groups depending on the fragment sizes, in which the groups A and B (B-1 and B-2) showed 400 and 460 bp, respectively. M. mizolepis was distinguished by a different pattern (400-, 460-, and 510-bp fragments). PCR–RFLP analyses of recombination activating gene 1 gave a clear difference between A or B-2 (443-bp fragment) and B-1 groups (296- and 147-bp fragments). Clonal lineages and hybrids between B-1 and B-2 groups could be identified by appearance of three fragments (443, 296, and 147 bp). The combined analyses using the above three nuclear markers discriminated among nuclear genomes of genetic groups (A, B-1 and B-2) of M. anguillicaudatus and M. mizolepis. In several localities, natural hybridizations between the group B-1 and B-2 loaches and introgressions of clonal mitochondrial genomes into the group B-1 loaches were detected. 相似文献
11.
Youji Wang Menghong Hu Weimin Wang Ling Cao Yi Yang Biping Lü Rongrong Yao 《Aquaculture International》2008,16(6):539-549
The diel feeding rhythm and ontogenesis during early life stage of loach Misgurnus anguillicaudatus were investigated under experimental conditions (light: L 06:00–18:00, D 18:00–06:00 h). Morphological and behavioral developments
of loach from newly hatched to 40 days after hatching were observed. Larvae were able to prey on daphnia 3–4 days after hatching
at 23 ± 0.5°C. As the larvae grew, they showed an increasing feeding capacity and a distinct feeding rhythm. Feeding intensity
and incidence for day-4 larvae were highest at 10:00 and 16:00 h. The highest levels of feeding intensity for day-12 larvae
occurred at 08:00, 12:00, and 18:00 h as did feeding incidence. By day 20, when the larvae metamorphosed, the highest levels
of feeding intensity occurred at 06:00, 18:00, and 24:00 h and were concurrent with the highest feeding incidence. After metamorphosis,
feeding capacity had again increased considerably and, in contrast to the earlier stages before day 20, feeding intensity
for day-30 juveniles peaked at 05:00 and 20:00 h, about 1–2 h after the maximum feeding incidence. The feeding rhythm of loach
juveniles at day 40 was almost the same as the day-30 juveniles. The estimated maximum daily feeding rates were 43.1%, 33.4%,
19.0%, 12.8%, and 5.8% of body weight on days 4, 12, 20, 30, and 40, respectively. Thus, loach was found to have different
feeding rhythms in the pre- and post-metamorphosis stages, with the highest feeding activity in daytime during the larval
planktonic stage before metamorphosis, and intensely nocturnal feeding behavior during the juvenile benthic stage after metamorphosis. 相似文献
12.
13.
Marianna Vaz Rodrigues Claire Juliana Francisco Gianmarco S. David Reinaldo José da Silva Maria Fernanda Falcone-Dias João Pessoa Araújo Júnior 《Aquaculture International》2018,26(1):127-138
Francisella noatunensis orientalis is a bacterium that causes emerging bacteriosis in Nile tilapia (Oreochromis niloticus) in many parts of the world, including Brazil. It is a non-motile, Gram-negative, strictly aerobic, facultative intracellular coccobacillus. This species of bacteria is responsible for low to high mortality in fish farms, causing economic losses for fish farmers. This study aimed to detect the presence of F. noatunensis orientalis using qPCR (real-time polymerase chain reaction) and to describe lesions caused by the bacterium in O. niloticus in Brazilian aquaculture. For this purpose, 360 fish from six fish farms (30 per farm) were sampled at two time points (n = 180 per sampling). Necropsies and histopathology were performed for lesion observation, in addition to qPCR and sequencing for detection and identification of Francisella species. Environmental data were collected using a multiparameter sonde YSI EXO2. All measured limnological variables were within the optimum range for cultivation of Nile tilapia. The major lesions present were melanization of the skin, splenomegaly, granulomas, and inflammatory cell responses. The prevalence of francisellosis varied from 0 to 86.66% between time periods and fish farms analyzed, and an outbreak was observed during the second sampling period. This study describes the prevalence of francisellosis in O. niloticus and reports that the lesions found are not exclusively associated with this bacterial disease. 相似文献
14.
Huayu Song Mengxun Wang Zhongkai Wang Jinxiang Liu Jie Qi Quanqi Zhang 《Fish physiology and biochemistry》2017,43(3):731-753
Reproduction allows organisms to produce offspring. Animals shift from immature juveniles into mature adults and become capable of sexual reproduction during puberty, which culminates in the first spermiation and sperm hydration or ovulation. Reproduction is closely related to the precise control of the hypothalamic–pituitary–gonadal (HPG) axis. Kisspeptin peptides are considered as the important regulator of HPG axis in mammalian. However, the current understanding of kisspeptin in flatfish is not comprehensive. In this study, we cloned and analyzed the kiss2 and kissr2 genes in Cynoglossus semilaevis. Interesting alternative splicing in the 5′-untranslated regions (UTR) of the Cskissr2 gene was found. The expression profiles of Cskiss2 and Cskissr2 showed relative high messenger RNA (mRNA) levels at the late gastrula stage during embryonic development, at total length = 40 mm during early gonadal differentiation, and in the brains and gonads of all investigated tissues. These results suggested that the kisspeptin system participated in embryogenesis and in the regulation of gonadal differentiation and development. Considering that the control and regulatory mechanisms of kisspeptin in the central reproductive axis are still unclear, we documented that the intramuscular injection of kisspeptin caused different sGnRH and cGnRH mRNA levels in a dose- and tissue-dependent manner. The mRNA expressions of FSH and LH were stimulated in the ovary and were inhibited in the testis under the kisspeptin treatments. These results provided foundations for understanding the roles of kisspeptin in the neuroendocrine system in fish. The manipulation of the kisspeptin system may provide new opportunities to control the gonadal development and even reproduction in fish. 相似文献
15.
The effect of aqueous extract of Cratoxylum formosum on innate immune response and disease resistance in tilapia Oreochromis niloticus was investigated. The fish were fed diets containing 0% (control), 0.5% (diet 1), 1% (diet 2), and 1.5% (diet 3) of C. formosum aqueous extract for 30 days. At the end of the experimental period, parameters of innate immune response including phagocytosis
of blood leukocytes, lysozyme activity in plasma, and respiratory bust activity were examined. Feeding the fish with diet
2 and diet 3 for 20 days enhanced phagocytic activity and for 30 days stimulated lysozyme and respiratory burst activities.
Diet 1 increased the phagocytic activity at 30 days, but did not affect the other measured parameters. All parameters were
not significantly changed (P > 0.05) in the control group throughout the experiment. Following 30 days of feeding, fish were infected with S. agalactiae. The cumulative mortalities of bacterial-infected tilapia that were fed diet 1, diet 2, and diet 3 were 56, 12, and 10%,
respectively, compared with 85% in the control group. These results indicate that the aqueous extract of C. formosum may elevate the innate immune response and enhance disease resistance in tilapia. 相似文献
16.
Arabinda Mahanty Sasmita Mohanty Bimal P. Mohanty 《Fish physiology and biochemistry》2017,43(4):1131-1141
Heat stress is one of the major environmental concerns in global warming regime and rising temperature has resulted in mass mortalities of animals including fishes. Therefore, strategies for high temperature stress tolerance and ameliorating the effects of heat stress are being looked for. In an earlier study, we reported that Nrf-2 (nuclear factor E2-related factor 2) mediated upregulation of antioxidative enzymes and heat shock proteins (Hsps) provide survivability to fish under heat stress. In this study, we have evaluated the ameliorative potential of dietary curcumin, a potential Nrf-2 inducer in heat stressed cyprinid Puntius sophore. Fishes were fed with diet supplemented with 0.5, 1.0, and 1.5% curcumin at the rate 2% of body weight daily in three separate groups (n = 40 in each group) for 60 days. Fishes fed with basal diet (without curcumin) served as the control (n = 40). Critical thermal maxima (CTmax) was determined for all the groups (n = 10, in duplicates) after the feeding trial. Significant increase in the CTmax was observed in the group fed with 1.5% curcumin- supplemented fishes whereas it remained similar in groups fed with 0.5%, and 1% curcumin-supplemented diet, as compared to control. To understand the molecular mechanism of elevated thermotolerance in the 1.5% curcumin supplemented group, fishes were given a sub-lethal heat shock treatment (36 °C) for 6 h and expression analysis of nrf-2, keap-1, sod, catalase, gpx, and hsp27, hsp60, hsp70, hsp90, and hsp110 was carried out using RT-PCR. In the gill, expression of nrf-2, sod, catalase, gpx, and hsp60, hsp70, hsp90, and hsp110 was found to be elevated in the 1.5% curcumin-fed heat-shocked group compared to control and the basal diet-fed, heat-shocked fishes. Similarly, in the liver, upregulation in expression of nrf-2, sod, catalase, and hsp70 and hsp110 was observed in 1.5% curcumin supplemented and heat shocked group. Thus, this study showed that supplementation of curcumin augments tolerance to high temperature stress in P. sophore that could be attributed to nrf-2-induced upregulation of antioxidative enzymes sod, catalase, gpx, and the hsps. 相似文献
17.
Ofelia S. Reyes Marietta N. Duray Corazon B. Santiago Manuele Ricci 《Aquaculture International》2011,19(1):155-164
The free-living nematode, Panagrellus redivivus, was tested as live food for grouper Epinephelus coioides larvae during the first feeding stage. A series of experiments were conducted to determine the acceptability of the free-living
nematodes in grouper larvae at first feeding, the optimum nematode density and the response of the larvae to nutritionally
enriched nematode. All experiments were conducted in 200-L conical tanks filled with 150-L filtered seawater and stocked at
15 larvae L−1. Duration of feeding experiments was up to day 21 (experiment 1) and 14 days (experiment 2 and 3). Brachionus plicatilis and Artemia (experiment 1) and Brachionus plicatilis alone (experiment 2 & 3) was used as the control treatment. Observations indicated that the grouper larvae readily fed on
free-living nematodes as early as 3 days posthatching, the start of exogenous feeding. Optimum feeding density for the larvae
was 75 nematodes ml−1. The enrichment of cod liver oil or sunflower oil influenced the total lipids and n-3 highly unsaturated fatty acids of P. redivivus, which in turn influenced those of the grouper larvae, however, growth and survival of the larvae were not affected (P > 0.05). The results from this investigation showed that the nematode, P. redivivus, can be used as first live food for grouper larvae from the onset of exogenous feeding until they could feed on Artemia nauplii. 相似文献
18.
We analysed the genetic diversity of Melicertus kerathurus (Penaeidae), a commercially valuable penaeid shrimp that is distributed in the Mediterranean Sea and eastern Atlantic Ocean.
We examined the polymorphism of a 494 bp DNA segment of the mitochondrial COI region in 173 individuals, sampled in nine Mediterranean
and two Atlantic samples, covering the whole range of the species from the tropical waters of the Gulf of Guinea to the eastern
part of the Mediterranean Sea. The mean nucleotide and haplotype diversities were π = 0.00275 and h = 0.718, respectively, for the global data set, with the highest values occurring in the African samples and the lowest in
the Adriatic Sea. A clear sample differentiation was found (F
st = 0.194), but this did not reflect a geographical pattern and there were only faint traces of an Atlantic–Mediterranean subdivision.
Mismatch analysis and a high significant negative value of Tajima’s D suggested that M. kerathurus is not at mutation drift-equilibrium, but underwent a recent expansion after a period of low effective sample size. A postglacial
recolonisation of the Mediterranean from an Atlantic refuge could be hypothesised based on these data. 相似文献
19.
Uriel Arreguin Rebolledo S. Nandini S. S. S. Sarma José Cristóbal Román Reyes Gustavo Alejandro Rodríguez Montes de Oca 《Aquaculture International》2018,26(2):629-644
We isolated the rotifers Brachionus ibericus and Proales similis from the sediment of shrimp tanks and studied their individual demographic characters and competition between them at two food levels (0.25?×?106, 1.00?×?106 cells ml?1 of Nannochloropsis oculata at 25 °C) and salinities ranging from 10 to 30‰. Our hypothesis was that growth rates would be higher with increasing food levels and salinities. Observations were taken twice a day for life table studies and daily once for population growth experiments. Using survivorship and fecundity data, we derived various life history variables. Although the average life span (7.6?±?0.4 days) and gross reproductive rate (33.8?±?2.9 neonate female?1 day?1) of B. ibericus were higher than those of P. similis (average life span 5.4?±?0.6 days and gross reproductive rate 13.0?±?0.6 neonate female?1 day?1), the population growth experiments showed that P. similis had higher r values (0.32?±?0.005 day?1) than B. ibericus (0.23?±?0.002 day?1) at 1.0?×?106 cells ml?1 of N. oculata. The rotifer P. similis was more adversely affected due to the presence of B. ibericus than vice versa. The data are important for developing techniques for a large-scale culture of these rotifers as food in aquaculture. 相似文献
20.
In this study, four essential oils—cinnamon oil, leech lime oil, lemongrass oil, and turmeric oil—were examined for their
antimicrobial activities against Streptococcus iniae, a bacterium that is pathogenic in fish, in which it causes streptococcosis. Cinnamon oil was the most potent antimicrobial
agent among these oils, with a minimal inhibitory concentration (MIC) of 40 μg/ml. By using gas chromatography–mass spectrometry
(GC–MS), it was found that the major components of cinnamon oil were cinnamaldehyde (90.24), limonene (2.42%), cinnamyl acetate
(2.03%), linalool (1.16%), and α-terpineol (0.87%). Of these compounds, only cinnamaldehyde exhibited antimicrobial activity
against S. iniae, with an MIC of 20 μg/ml. In an in vivo trial, no mortality was apparent in fish fed on fish diets supplemented with 0.4%
(w/w) of cinnamon oil and with 0.1% (w/w) of oxytetracycline 5 days prior to infection with S. iniae. These results indicate that cinnamon oil had a protective effect on experimental S. iniae infection in tilapia, and thus has the potential to replace the antibiotics used to control this disease. 相似文献