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81.
Zohreh Sankian Sanaz Khosravi Yi‐Oh Kim Sang‐Min Lee 《Journal of the World Aquaculture Society》2019,50(1):34-41
An 8‐week feeding trial was conducted to investigate the dietary protein requirement of juvenile mandarin fish, Siniperca scherzeri, a demersal freshwater piscivore with high commercial value in East Asia. Five isolipidic (100 g/kg) and isoenergetic (20 MJ/kg) practical diets were formulated to contain graded levels of 450, 500, 550, 600, and 650 g/kg crude protein, using mackerel fishmeal as the sole source of protein. Each of the five test diets was fed to visual satiety to triplicate groups of fish (initial mean body weight ± SE; 20.1 ± 0.2 g) reared in a recirculating freshwater system over the experimental period. Fish growth performance in terms of weight gain tended to improve with increasing dietary protein level, and the highest values were observed in those fish fed the 600–650 g/kg diets. Feed intake significantly declined as the protein content of the diet increased. Feed efficiency and protein retention tended to increase with increasing dietary protein levels, from 450 to 600 g/kg, and then declined when dietary protein content further increased to 650 g/kg. A similar trend was also found for the protein efficiency ratio, although the observed changes did not reach statistical significance. Whole‐body composition and plasma biochemical parameters were not significantly affected by the dietary protein content. Based on these findings and a broken‐line model of growth, 614.4 g/kg seems to be the proper amount of protein in a practical diet for >20 g mandarin fish. 相似文献
82.
Kim Birnie‐Gauvin Lasse Birch Hjrup Theis Kragh Lene Jacobsen Kim Aarestrup 《Ecology of Freshwater Fish》2019,28(3):376-384
Pike (Esox lucius) occupy coastal streams and rivers of the Baltic Sea, where they attain large sizes (>5 kg). These large sizes are perhaps due to the fact that they can tolerate relatively high salinities and can thus forage in the nearby more productive brackish environments. In an attempt to quantify the extent to which pike utilise brackish environments, and to provide some insight into the underlying causes for brackish water migrations, we tagged 30 pike from a western Baltic river with acoustic transmitters and were able to track 21 individuals for 1 year. Based on experienced from local anglers, this population was assumed to be brackish in nature, where individuals underwent freshwater migrations to spawn. Our findings however suggest that the smallest and most active individuals make short exits into brackish waters and do so on rare occasions. Our results further indicate that neither sex nor size is related to activity level. We suggest that these patterns reflect two distinct behaviours—active and passive—and that large pike can be supported by the food availability in the river, without the need to venture into coastal zones, thus defying the conventional view that Baltic pike are all brackish in nature. 相似文献
83.
Haejeen Bang Gangman Yi Sunggil Kim Daniel Leskovar Bhimanagouda S. Patil 《Euphytica》2014,200(3):363-378
In the carotenoid biosynthetic pathway, lycopene β-cyclase (LCYB) catalyzes the cyclization that converts lycopene into β-carotene. Only a single copy of LCYB was identified and was suggested to encode a chromoplast-specific LCYB (CYCB type) in watermelon [Citrullus lanatus (Thunb.), Matsum & Nakai]. Splicing variants in the 5′-untranslated region were identified, but alternative splicing did not provide an explanation of the regulation of carotenoid accumulation in watermelon flesh. A quantitative assay using real time-PCR showed that differential expression was not detected between red- and canary yellow-fleshed watermelon cultivars. LCYB promoter regions were isolated and characterized, and a sequence difference was identified in the promoter region between red and canary yellow LCYB alleles. This polymorphism did not change the expression of LCYB, but does provide a reliable marker for discriminating LCYB alleles for red and canary yellow flesh. To develop a PCR-based marker to distinguish between the two LCYB alleles, we designed primers flanking the polymorphic region. The newly developed marker, designated Clcyb.600, co-segregated perfectly with flesh color phenotypes and single nucleotide polymorphism (SNP) markers developed in our previous study. Moreover, the Clcyb.600 marker offers easier discrimination of LCYB alleles than SNP or cleaved amplified polymorphic sequence markers, as it does not require restriction enzyme digestion for genotyping. Genotyping of LCYB promoter alleles in various commercial cultivars and plant introductions indicated that watermelon cultivars can be classified into two groups, those carrying a red LCYB allele or a canary yellow LCYB allele. 相似文献
84.
Hoy-Taek Kim Yutaka Hirata Yong-Uk Shin Hae-Sung Hwang Jeong-Hwan Hwang Il-Sheob Shin Dae-Il Kim Sang-Jo Kang Hyun-Jung Kim Dong-Young Shin Ill-Sup Nou 《Euphytica》2004,138(1):73-80
The pear cultivar ‘Osa-Nijisseiki’ (S2Ssm
4; sm = stylar-part mutant) has been used as a parent to breed self-compatible cultivars that produce excellent fruits. However,
determination of the self-compatibility of ‘Osa-Nijisseiki’ offspring requires a lot of time, 6 years or more, by conventional
cross breeding. We have designed a rapid reliable method for the identification of self-compatible varieties of ‘Osa-Nijisseiki’
offspring based on the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with S-allele specific
restriction endonucleases. By using this method, 8 self-compatible varieties were selected among 16 selections resulting from
a cross between the self-compatible cultivar ‘Osa-Nijisseiki’ (S2Ssm
4) and the self-incompatible cultivars ‘Niitaka’ (S3S9), ‘Whasan’ (S3S5), ‘Chuwhangbae’ (S4S6). The S-genotypes of 16 ‘Osa-Nijisseiki’ offsprings were also determined.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
85.
Isolated plant microspores, when stressed and cultured in vitro, can be diverted from their normal gametophytic pathway towards
sporophytic development, with the formation of haploid embryos and ultimately doubled-haploid plants. This process is called
androgenesis or microspore embryogenesis, and is widely used in plant breeding programmes to generate homozygous lines for
breeding purposes. Protocols for the induction of microspore embryogenesis and the subsequent regeneration of doubled haploid
(DH) plants have been successfully developed for more than 200 species. These practical advances stand in stark contrast to
our knowledge of the underlying molecular genetic mechanism controlling this process. The majority of information regarding
the genetic and molecular control of the developmental switch from gametophytic to sporophytic development has been garnered
from four intensely studied (crop) plants comprising two dicotyledonous species, rapeseed (Brassica napus) and tobacco (Nicotiana tabacum), and two monocotyledonous species, wheat (Triticum aestivum) and barley (Hordeum vulgare). In these species the efficiency of microspore embryogenesis is very high and reproducible, making them suitable models
for molecular studies. In the past, molecular studies on microspore embryogenesis have focussed mainly on the identification
of genes that are differentially expressed during this developmental transition and/or early in embryo development, and have
identified a number of genes whose expression marks or predicts the developmental fate of stressed microspores. More recently,
functional genomics approaches have been used to obtain a broad overview of the molecular processes that take place during
the establishment of microspore embryogenesis. In this review we summarise accumulated molecular data obtained in rapeseed,
tobacco, wheat and barley on embryogenic induction of microspores and define common aspects involved in the androgenic switch. 相似文献
86.
Jundae Lee Jae Bok Yoon Jung-Heon Han Won Phil Lee Sang Hoon Kim Hyo Guen Park 《Euphytica》2010,173(1):55-61
Genic male sterility (GMS) has long been used as a tool for hybrid seed production in chili pepper (Capsicum annuum L.). We developed DNA markers linked to the GMS ms
3
gene in a segregating population using bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP)
techniques. The segregating population was subjected to BSA-AFLP with 512 primer combinations. Three AFLP markers (Eagg/Mccc276, Eagc/Mctt178, and Ecag/Mtgc204) were identified as tightly linked to the ms
3
locus. Among them, we converted the AFLP marker Ecag/Mtgc204 to the cleavage amplified polymorphic sequence (CAPS) marker, named GMS3-CAPS, based on sequencing analysis of internal and
flanking regions for the markers between male-fertile and sterile plants. This marker will be useful for pepper breeding using
the GMS system. 相似文献
87.
Avian poxvirus was isolated from nodules on the heads and conjunctiva of two 3-to-4-wk-old ostrich chicks. The ostriches from which poxvirus was isolated had been placed on premises where turkeys that had shown evidence of poxvirus infection had been raised earlier. Microscopically, the nodules from the ostriches were composed of proliferating and hypertrophic epithelial cells that formed large fronds. Most of the hypertrophic epithelial cells contained large eosinophilic intracytoplasmic inclusion bodies characteristic of poxvirus. Characterization of the avian poxvirus isolated from the cutaneous lesions in ostriches was based on western blotting of virus antigen, restriction fragment length polymorphism of genomic DNA, pathogenesis, and cross-protection studies in chickens. Antigenic and genetic studies did not reveal any significant difference between the poxvirus isolated from ostriches (PVO) and fowl poxvirus (FPV). Further, susceptible chickens immunized with the PVO were protected when challenged with a virulent strain of FPV. Thus, the poxvirus isolated from ostriches had similar antigenic, genetic, and biological properties to FPV. 相似文献
88.
Mun Sup Yoon Jeongran Lee Chang Yung Kim Jung Hoon Kang Eun Gi Cho Hyung Jin Baek 《Euphytica》2009,165(1):69-77
Approximately 7,000 accessions of Korean soybean (Glycine max (L.) Merrill) landraces, largely composed of three collections, the Korea Atomic Energy Research Institute’s soybean (KAS),
the Korean Crop Experiment Station’s soybean (KLS) and the Korean Agricultural Development and Technology Center’s soybean
(KADTC) collections, have been conserved at the Rural Development Administration (RDA) genebank in Korea. The accessions within
collections were classified based on their traditional uses such as sauce soybean (SA), sprouted soybean (SP), soybean for
cooking with rice (SCR), and OTHERS. A total of 2,758 accessions of Korean soybean landraces were used to profile and to evaluate
genetic structure using six SSR loci. A total of 110 alleles were revealed by at the six SSR loci. The number of alleles per
SSR locus ranged from 9 to 39 in Satt187 and Satt_074, respectively. The number of alleles ranged from 87 in the KADTC collection
to 96 in the KLS collection, and from 63 in the SCR group to 95 in the SP group. Nei’s average genetic diversity ranged from
0.68 to 0.70 across three collections, and 0.64 to 0.69 across the usage groups. The average between-group differentiation
(G
st) was 0.9 among collections, and 4.1 among the usage groups. The similar average diversity among three collections implies
that the genetic background of the three collections was quite similar or that there were a large number of duplicate accessions
in three collections. The selection from the four groups classified based upon usage may be a useful way to select accessions
for developing a Korean soybean landrace core collection at the RDA genebank. DNA profile information of accessions will provide
indications of redundancies or omissions and aid in managing the soybean collection held at the RDA genebank. The information
on diversity analysis could help to enlarge the genetic diversity of materials in breeding programs and could be used to develop
a core collection. 相似文献
89.
Jeong CK Lee HY Kim SB Choi SJ Kim JH Kim K Han SS Lee HS 《Pest management science》2001,57(5):427-431
To investigate the hepatic metabolism of the new insecticide flupyrazofos [O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphorothioate], isolated rat liver was perfused with flupyrazofos under single-pass conditions. In outflow perfusate and bile, 1-phenyl-3-trifluoromethyl-5-hydroxyprazole (PTMHP), PTMHP-sulfate and PTMHP-glucuronide conjugates were identified as the metabolites of flupyrazofos. However, O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphate (flupyrazofos oxon) was not detected. A HPLC method with UV detection was used to investigate the hepatic disposition of flupyrazofos and its metabolite PTMHP. The concentrations of flupyrazofos, PTMHP and PTMHP conjugates in outflow perfusate reached steady-state levels within 20 min after commencing perfusion of 7.3 microM flupyrazofos. At steady state, the mean extraction ratio of flupyrazofos was 0.93 (+/- 0.01) and clearance was 26.1 (+/- 0.2) ml min-1 which nearly approached perfusate flow rate (28 ml min-1). PTMHP accounted for 55.7 (+/- 5.8)% of eliminated flupyrazofos and was recovered as unchanged PTMHP, PTMHP-sulfate and PTMHP-glucuronide in the bile as well as the outflow perfusate. 相似文献
90.
Effect of catheter size and injection rate of contrast agent on enhancement and image quality for triple‐phase helical computed tomography of the liver in small dogs 下载免费PDF全文
Sang‐Kwon Lee Dahae Lee Dongeun Kim Ahyoung Cha Jihye Choi 《Veterinary radiology & ultrasound》2017,58(6):664-670
Rapid contrast injection is recommended for triple‐phase helical computed tomography (CT) of the liver. However, a large‐gauge catheter is needed for faster contrast injection and this is not practical for small breed dogs or cats. The purpose of this crossover group study was to evaluate applicability of a lower injection rate with a small‐gauge (G) catheter for triple‐phase hepatic CT in small dogs. Triple‐phase CT images were acquired for six beagle dogs using three protocols: an injection rate of 1.5 ml/s with a 24 G catheter, 3.0 ml/s with a 22 G catheter, and 4.5 ml/s with a 20 G catheter. Enhancement of the aorta, portal vein, and hepatic parenchyma was measured in each phase (arterial, portal, and delayed) and image quality was scored subjectively by two observers. Injection duration, time to scan delay, and time to peak enhancement were also recorded. Contrast injection duration decreased with a higher injection rate (n = 6, P ≤ 0.01), but time to peak enhancement and time to scan delay were not significantly affected by injection rates and catheter sizes. Contrast injection rate did not significantly affect aortic, portal, and hepatic enhancement. In addition, separation between each phase and quality of images was subjectively scored as good regardless of injection rate. Findings from the current study supported using an injection rate of 1.5 ml/s with a catheter size of 24 G for triple‐phase hepatic CT in small dogs (weight < 12 kg). 相似文献