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101.
Partho Pratim Debnath Nguyen Dinh-Hung Suwimon Taengphu Vuong Viet Nguyen Jerome Delamare-Deboutteville Saengchan Senapin Chadag Vishnumurthy Mohan Ha Thanh Dong Channarong Rodkhum 《Journal of fish diseases》2022,45(1):77-87
Sixteen countries, including Bangladesh, have reported the presence of tilapia lake virus (TiLV), an emerging tilapia pathogen. Fish polyculture is a common farming practice in Bangladesh. Some unusual mortalities reported in species co-cultivated with TiLV-infected tilapia led us to investigate whether any of the co-cultivated species would also test positive for TiLV and whether they were susceptible to TiLV infection under controlled laboratory experiments. Using 183 samples obtained from 15 farms in six districts across Bangladesh, we determined that 20% of the farms tested positive for TiLV in tilapia, while 15 co-cultivated fish species and seven other invertebrates (e.g. insects and crustaceans) considered potential carriers all tested negative. Of the six representative fish species experimentally infected with TiLV, only Nile tilapia showed the typical clinical signs of the disease, with 70% mortality within 12 days. By contrast, four carp species and one catfish species challenged with TiLV showed no signs of TiLV infection. Challenged tilapia were confirmed as TiLV-positive by RT-qPCR, while challenged carp and walking catfish all tested negative. Overall, our field and laboratory findings indicate that species used in polycultures are not susceptible to TiLV. Although current evidence suggests that TiLV is likely host-specific to tilapia, targeted surveillance for TiLV in other fish species in polyculture systems should continue, in order to prepare for a possible future scenario where TiLV mutates and/or adapts to new host(s). 相似文献
102.
From mid-2004 to mid-2005, several grass carp, Ctenophayngodon idella (Valenciennes), showing evidence of spinal deformity were presented to the Aquatic Animal Health Program, Cornell University. The carp were from three separate locations in New York State. The first case involved several fish from a natural body of water in the Catskill Mountain region of south-eastern New York State. The second was a single affected individual from a private pond in the Fingerlakes region of Central New York State. The third was a single individual from the Cold Springs Harbor Fish Hatchery, Cold Springs Harbor, Long Island. All fish were at least 7 years of age. Radiographs and computed tomography (CT) scans revealed the deformities to be of bony origin. The spinal deformities were characterized by variable amounts of kyphosis, scoliosis and rotation. While it is not possible to determine the specific cause(s) of the lesions, we consider a genetic component as a likely contributor to the observed pathology. 相似文献
103.
104.
约10000余尾注射牛和羊生长激素基因的鲤鱼已被生产出来,并从中筛选出生长速度快且整合了外源基因的个体143尾,也证明外源基因可传递给子代同时子代也具有快速生长的特征。建立了把外源基因直接注入受精卵的方法,确定了注入外源基因的最佳时期。 相似文献
105.
106.
Microsatellites have become the preferred molecular markers for strain selection and genetic breeding in fish. In this study
a total of 105 microsatellites were isolated and identified in gibel carp (Carassius auratus gibelio) by microsatellite sequence searches in GenBank and other databases and by screening and sequencing of positive clones from
the genomic library enriched for AG and GATA repeats. Moreover, nineteen microsatellites were randomly selected to design
locus-specific primer pairs, and these were successfully used to identify and discriminate different cultured strains of gibel
carp including strains A, D, L, and F. Three different types of microsatellite pattern were distinguished by the number and
length of fragments amplified from the 19 primer pairs, and some microsatellite primer pairs were found to produce different
microsatellite patterns among strains and strain-specific fragments. In addition, some duplicated alleles were also detected
in two microsatellite patterns. Therefore, the current study provides direct molecular markers to discriminate among different
cultured strains for selective breeding and aquaculture practice of gibel carp. 相似文献
107.
The objective of this study was to evaluate of the growth performance, serum biochemical indices, liver antioxidant parameters and ability of anti-infection with Aeromonas hydrophila by adding the fermented Chinese medicine by Bacillus Subtilis to the carp fish feed, and to find out the appropriate supplemental level of fermented Chinese medicine in diets. Carp fingerling with an initial body weight of (35±0.5) g were set up to 6 experimental diets supplemented with 0 (control group), 0.1‰, 0.5‰, 1‰, 2‰ and 3‰ fermented Chinese medicine for 56 days, respectively. Each group had 30 fish and set up 3 repetitions. After the feeding trail,the fish were challenged with Aeromonas hydrophila to calculate the relative percentage survival (RPS).The results showed as follows:Supplementing fermented traditional Chinese medicine by Bacillus subtilis, the weight gain rate (WGR), specific growth rate (SGR), condition factor (CF), the activities of lysozyme (LSZ), complement 3 (C3),total protein (TP),total anti-oxidation capacity (T-AOC),total superoxide dismutase (T-SOD) and catalase (CAT) in serum of common carp were enhanced at different degrees, while the feed coefficient (FCR)and malondialdehyde (MDA) in serum were declined at different degrees.When the fermented Chinese medicine supplemental levels were 2‰ and 3‰,the effects were significant (P<0.05)(except for C3, ALP and Cr).The experimental results of the virulence of common carp infected with pathogen Aeromonas hydrophila showed that,the fermented herbal could obviously improve the ability of anti-infection, the immune protective rate of the group with 2‰, 3‰ doses of the fermented Chinese medicine could reach 77.23% and 74.63%, respectively. From what had been discussed above, the group with 2‰ and 3‰ doses of the fermented Chinese medicine had significant effect on the growth performance, serum biochemical indices, liver antioxidant parameters and Aeromonas hydrophila anti-infection ability. Considering the cost of adding fermented Chinese medicine, the recommendations for the best additive quantity was 2‰. 相似文献
108.
鳙小卫星DNA的克隆 总被引:6,自引:2,他引:4
鳙基因组DNA 经内切酶Sau3AⅠ完全酶切后,与Bam HⅠ- pUC18 质粒连接,转化DH5α后,获得933 个重组体。用人源小卫星探针33 .15 对重组体进行原位杂交筛选,获得14 个阳性克隆,取其中的1 个阳性克隆( 即小卫星pBC174) 作探针,与5 尾鳙和4 尾鲢基因组DNA 杂交,能产生具有高度变异性的、个体特异性的DNA 指纹图,表明克隆的鳙小卫星pBC174 可用于鱼类DNA 指纹分析。 相似文献
109.
ABSTRACT: The present study, one in a series to clarify the phosphorus (P) and nitrogen (N) loading from carp culture, evaluated four commercial diets. The total and available P in these diets varied from 1.57 to 1.86% and from 0.38 to 0.87%, respectively. The control diet, selected based on an earlier experiment, contained 1.40% total P and 0.68% available P. The 7-week feeding trial was performed with juvenile carp. Superior feed gain ratio was obtained for the control diet (1.00) and it varied from 1.19 to 1.56 among the commercial diet groups. Similarly, the control diet showed higher rates of P absorption (43.8%) and retention (33.1%) than the rest (absorption: 18.1–40.9%; retention: 10.7–18.7%). Total P loading (kg/t production) was 10.0 for the control group but ranged from 19.1 to 25.0 among the commercial diet groups. Nitrogen absorption was not markedly different; however, fluctuations in retention resulted in N loading (kg/t production) that ranged between 47.1 and 66.3 among the commercial diets, higher than the 34.8 obtained for the control diet. The available P in the commercial diets rarely matched the requirement level, thereby negatively affecting the waste loading. The superior performance of the control diet underscores the fact that effective formulations help in keeping emission levels low. 相似文献
110.
饲料中不同脂肪酸对草鱼组织脂质含量和脂肪酸构成的影响 总被引:17,自引:1,他引:16
实验选用初始作重约1.4g的草鱼,在60天的饲养期中分别投喂1种不含脂肪的饲料和8种含3%不同脂质的饲料,观察了饲料中添加油酸(18:1n-9)、亚油酸(18:2n-6)、亚麻酸(18:3n-3)和n-3系列高度不饱和脂肪酸(n-3HUFA;20:5n-3+22:6n-3)对草鱼肝胰脏、肌肉、头部和去肝胰脏内脏脂质含量和脂肪酸构成的影响。实验结果表明,与摄食单纯含油酸饲料的草鱼相比,含1%18:2n-6和1%18:3n-3或1%18:2n-6和0.5%n-3HUFA饲料组草鱼的肝胰脏脂质含量显著降低,但内脏脂质含量升高。向饲料中添加18:2n-6、18:3n-3和n-3HUFA能明显影响草鱼肝胰脏、肌肉和头部脂质多不饱和脂肪酸的相对含量;组织中n-6系列和n-3系列高度不饱和脂肪酸含量分别与饲料中添加18:2n-6和18:3n-3有相关关系,表明草鱼具有生物转化18:2n-6和18:3n-3为高度不饱和脂肪酸的能力。 相似文献