Astaxanthin Normalizes Epigenetic Modifications of Bovine Somatic Cell Cloned Embryos and Decreases the Generation of Lipid Peroxidation          下载免费PDF全文

R Li  H Wu  WW Zhuo  QF Mao  H Lan  Y Zhang  S Hua 《Reproduction in domestic animals》2015,50(5):793-799

Astaxanthin is an extremely common antioxidant scavenging reactive oxygen species (ROS) and blocking lipid peroxidation. This study was conducted to investigate the effects of astaxanthin supplementation on oocyte maturation, and development of bovine somatic cell nuclear transfer (SCNT) embryos. Cumulus–oocyte complexes were cultured in maturation medium with astaxanthin (0, 0.5, 1.0, or 1.5 mg/l), respectively. We found that 0.5 mg/l astaxanthin supplementation significantly increased the proportion of oocyte maturation. Oocytes cultured in 0.5 mg/l astaxanthin supplementation were used to construct SCNT embryos and further cultured with 0, 0.5, 1.0 or 1.5 mg/l astaxanthin. The results showed that the supplementation of 0.5 mg/l astaxanthin significantly improved the proportions of cleavage and blastulation, as well as the total cell number in blastocysts compared with the control group, yet this influence was not concentration dependent. Chromosomal analyses revealed that more blastomeres showed a normal chromosomal complement in 0.5 mg/l astaxanthin treatment group, which was similar to that in IVF embryos. The methylation levels located on the exon 1 of the imprinted gene H19 and IGF2, pluripotent gene OCT4 were normalized, and global DNA methylation, H3K9 and H4K12 acetylation were also improved significantly, which was comparable to that in vitro fertilization (IVF) embryos. Moreover, we also found that astaxanthin supplementation significantly decreased the level of lipid peroxidation. Our findings showed that the supplementation of 0.5 mg/l astaxanthin to oocyte maturation medium and embryo culture medium improved oocyte maturation, SCNT embryo development, increased chromosomal stability and normalized the epigenetic modifications, as well as inhibited overproduction of lipid peroxidation.  相似文献   

PROGRESS ON IMPROVING AGRICULTURAL NITROGEN USE EFFICIENCY: UK-CHINA VIRTUAL JOINT CENTERS ON NITROGEN AGRONOM     

Tom MISSELBROOK  Zhaohai BAI  Zejiang CAI  Weidong CAO  Alison CARSWELL  Nicholas COWAN  Zhenling CUI  David CHADWICK  Bridget EMMETT  Keith GOULDING  Rui JIANG  Davey JONES  Xiaotang JU  Hongbin LIU  Yuelai LU  Lin MA  David POWLSON  Robert M. REES  Ute SKIBA  Pete SMITH  Roger SYLVESTER-BRADLEY  John WILLIAMS  Lianhai WU  Minggang XU  Wen XU  Fusuo ZHANG  Junling ZHANG  Jianbin ZHOU  Xuejun LIU 《农业科学与工程前沿(英文版)》2022,9(3):475

● Virtual joint centers on N agronomy were established between UK and China. ● Key themes were improving NUE for fertilizers, utilizing livestock manures, and soil health. ● Improved management practices and technologies were identified and assessed. ● Fertilizer emissions and improved manure management are key targets for mitigation. Two virtual joint centers for nitrogen agronomy were established between the UK and China to facilitate collaborative research aimed at improving nitrogen use efficiency (NUE) in agricultural production systems and reducing losses of reactive N to the environment. Major focus areas were improving fertilizer NUE, use of livestock manures, soil health, and policy development and knowledge exchange. Improvements to fertilizer NUE included attention to application rate in the context of yield potential and economic considerations and the potential of improved practices including enhanced efficiency fertilizers, plastic film mulching and cropping design. Improved utilization of livestock manures requires knowledge of the available nutrient content, appropriate manure processing technologies and integrated nutrient management practices. Soil carbon, acidification and biodiversity were considered as important aspects of soil health. Both centers identified a range of potential actions that could be taken to improve N management, and the research conducted has highlighted the importance of developing a systems-level approach to assessing improvement in the overall efficiency of N management and avoiding unintended secondary effects from individual interventions. Within this context, the management of fertilizer emissions and livestock manure at the farm and regional scales appear to be particularly important targets for mitigation.  相似文献   

Polka-dot grouper, Cromileptes altivelis, can utilize dietary fat efficiently     

I. WILLIAMS  K.C. WILLIAMS  D.M. SMITH  & M. JONES 《Aquaculture Nutrition》2006,12(5):379-387

Polka‐dot grouper, Cromileptes altivelis, a highly‐prized fish in Asian live fish markets, is a slow‐growing species. Long‐chain (LCF) or medium‐chain fatty acids (MCF) were fed to polka‐dot grouper (14 g initial weight) for 8 weeks to see if growth could be stimulated. Five dietary treatments were compared: a control diet with low fat (56 g kg^?1) or diets that contained either moderate (150 g kg^?1) or high (300 g kg^?1) supplements of fat that were added either as olive oil for the LCF or coconut oil for the MCF. Control fish performed well; they grew at 2.2 g week^?1, had a dry matter feed conversion ratio of 1.0 and deposited dietary protein and energy at efficiencies of 25 and 26%. Fish fed LCF at moderate levels performed better than controls but, when fed LCF at high levels or MCF at any level, their performance was inferior to controls. We conclude that dietary supplementation with 150 g kg^?1 of LCF stimulates growth and improves protein retention of polka‐dot grouper whereas higher levels, or the same or higher levels of MCF, depress performance.  相似文献   

Hepatocellular carcinoma and fatty infiltration in the Atlantic tomcod, Microgadus tomcod (Walbaum)     

S. M. CORMIER  R. N. RACINE  C. E. SMITH  W. P. DEY  T. H. PECK 《Journal of fish diseases》1989,12(2):105-116

Abstract. The livers of Atlantic tomcod, Microgadus tomcod (Walbaum), from the Hudson and Pawcatuck Rivers were evaluated histologically and described using paraffin and plastic sections. Fatty infiltration, basophilic foci, areas of cellular alteration and hepatocellular carcinoma were widespread in Hudson River samples. In fact, no truly normal tissues were found. Pawcatuck samples had variable levels of lipid and a low prevalence of other alterations. Evaluation of the histological evidence suggests that hepatocellular carcinoma in Hudson River tomcod results from multiple DNA lesions and that areas of cellular alteration give rise to the larger, more invasive form of hepatocellular carcinoma. Glutaraldehyde and OsO₄ fixed livers were used to determine differences in cell types and lipid levels. Pawcatuck samples possessed hepatocytes and dark cells forming the parenchymal tissue, whereas Hudson samples lacked dark cells. Hepatic lipid levels were significantly higher in Hudson River fish than in Pawcatuck fish, 36·3 and 11·0% respectively. The elevated hepatic lipid levels in Hudson River tomcod may represent a metabolic response to detoxification.  相似文献   

Characterization of a host response to the myxosporean parasite, Ceratomyxa shasta (Noble), by histology, scanning electron microscopy and immunological techniques   总被引：2，自引：0，他引：2  

J. L. BARTHOLOMEW  C. E. SMITH  J. S. ROHOVEC  J. L. FRYER 《Journal of fish diseases》1989,12(5):509-522

Abstract. The tissue response of Salmo gairdneri Richardson, against the myxosporean parasite. Ceratomyxa shasta (Noble), was investigated using histological techniques, scanning electron microscopy and immunological methods. The progress of infection in C. shasta -susceptible and resistant steelhead and rainbow trout was examined by standard histological techniques and by indirect fluorescent antibody methods using monoclonal antibodies directed against C. shasta antigens. Trophozoite stages were first observed in the posterior intestine and there was indication that resistance was due to the inability of the parasite to penetrate this tissue rather than to an inflammatory response. Examination of a severely infected intestine by scanning electron microscopy showed extensive destruction of the mucosal folds of the posterior intestine. Western blotting and indirect fluorescent antibody techniques were used to investigate the immunological component of the host response. No antibodies specific for C. shasta were detected by either method.  相似文献   

The isolation of a rickettsia-like organism causing disease and mortality in Chilean salmonids and its confirmation by Koch's postulate   总被引：5，自引：0，他引：5  

J. D. CVITANICH  O. GARATE N.  C. E. SMITH 《Journal of fish diseases》1991,14(2):121-145

Abstract. A rickettsia-like organism (RLO) was isolated from infected coho salmon, Oncorhynchus kisutch (Walbaum), in cultures from six fish cell lines, but could not be cultured on 41 artificial media. The organism was confirmed by Koch's postulates as the aetiological agent of a systemic disease causing signifieant mortality among coho in Chile. The organism was a Gram-negative, obligate intracellular pathogen frequently observed within intracyto-plasmic vacuoles or inclusions of host cells, and appears to belong to the order Rickettsiales, family Rickettsiaceae and possibly the tribe Ehrlichiae. The organism, as well as the clinical signs and pathology it produces, is described. The disease, originally observed only in coho raised in seawater net pens, was reproduced experimentally in fish in both freshwater and seawater aquaria. Horizontal transmission without parasite vectors was observed in fish in both aquaria. The organism was shown, for the first time, to cause disease and mortality in Atlantic, Salmo salar L., and Chinook, O. tshawytscha (Walbaum), salmon and rainbow trout, O. mykiss (Walbaum). Because of the systemic nature of the disease, it is proposed that it be called 'salmonid rickettsial septicaemia'.  相似文献   

Ocular metacercarial infection of the oyster toadfish, Opsanus tau (L.)     

R. C. RIIS  M. E. GEORGI  L. LEIBOVITZ  J. S. SMITH 《Journal of fish diseases》1981,4(5):433-435

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A Survey of Aquatic Fly-life on the River Tweed*     

DEREK MILLS  BARBARA SMITH 《Aquaculture Research》1974,5(3):72-84

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The relationship between stock and catch and the effect of bait on catch as determined for a UK recreational catch and release fishery     

P. A. SMITH 《Fisheries Management and Ecology》2002,9(5):261-266

Abstract Twelve anglers fishing in a UK navigation canal for a total of 42 h caught 567 fish, mainly gudgeon, Gobio gobio (L.) ( n =306) and roach, Rutilus rutilus (L.) ( n =253) at an average catch rate of 13.4 fish angler-h⁻¹ or 128.5 g angler-h⁻¹. The species and size of fish caught were compared with the numbers determined by depletion estimates at six sections of canal using micromesh seine netting. Fifty four percent of fish caught in the net were < 60 mm FL. Gudgeon (60–99 mm) were over-represented in the anglers' catches whilst roach (60–99 mm) were under-represented. The size distribution of roach and gudgeon caught by anglers using two types of bait (small maggots and chironomid larvae) was examined and smaller fish were found to be caught using the latter.  相似文献   

Is salmon angling success gender biased? An analysis of catch records     

G. W. SMITH  R. LAUGHTON  and S. DORA 《Fisheries Management and Ecology》1994,1(2):139-141

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