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Christian Schlechtriem Ulfert Focken Klaus Becker 《Journal of the World Aquaculture Society》2005,36(1):24-31
The free-living nematode Panagrellus redivivus is a potential source of live food for first feeding fish. The digestion and assimilation of nematodes by larval fish were investigated with the aid of a histological and stable isotope approach. Larvae of whitefish Coregonus lavaretus were reared for 8 d with nematodes and compared with an unfed control. Nematodes were readily ingested by 3-d-old larvae. Different stages of nematode digestion could be observed in transverse sections of fish larvae sampled on Day 6 at regular intervals after feeding. Nematodes were produced on corn medium. In this way nematodes with a stable carbon isotope signature clearly different from the isotopic pattern of the fish larvae could be obtained. Stable carbon isotope signatures for lipids and lipid-free matter of fish larvae sampled on Days 2 and 8 after first feeding were clearly influenced by the stable isotopic pattern of the nematodes. The high acceptance of the nematodes by Coregonus lavaretus larvae and the early onset of digestion and nutrient retention positively confirm the potential of PanagreUus redivivus as a live food for first feeding fish larvae. 相似文献
87.
Arnhold SJ Goletz I Klein H Stumpf G Beluche LA Rohde C Addicks K Litzke LF 《American journal of veterinary research》2007,68(10):1095-1105
OBJECTIVE: To isolate and characterize bone marrow-derived equine mesenchymal stem cells (MSCs) for possible future therapeutic applications in horses. SAMPLE POPULATION: Equine MSCs were isolated from bone marrow aspirates obtained from the sternum of 30 donor horses. PROCEDURES: Cells were cultured in medium (alpha-minimum essential medium) with a fetal calf serum content of 20%. Equine MSC features were analyzed to determine selfrenewing and differentiation capacity. For potential therapeutic applications, the migratory potential of equine MSCs was determined. An adenoviral vector was used to determine the transduction rate of equine MSCs. RESULTS: Equine MSCs can be culture-expanded. Equine MSCs undergo cryopreservation in liquid nitrogen without altering morphologic characteristics. Furthermore, equine MSCs maintain their ability to proliferate and differentiate after thawing. Immunocytochemically, the expression of the stem cell marker CD90 can be detected on equine MSCs. The multilineage differentiation potential of equine MSCs was revealed by their ability to undergo adipogenic, osteogenic, and chondrogenic differentiation. CONCLUSIONS AND CLINICAL RELEVANCE: Our data indicate that bone marrow-derived stromal cells of horses can be characterized as MSCs. Equine MSCs have a high transduction rate and migratory potential and adapt to scaffold material in culture. As an autologous cell population, equine MSCs can be regarded as a promising cell population for tissue engineering in lesions of the musculoskeletal system in horses. 相似文献
88.
Mixed modelling for QTL × environment interaction analysis 总被引:2,自引:0,他引:2
Phenotypic data for quantitative trait loci (QTL) mapping studies are typically generated at multiple environments in order
to broaden the inference space. Many aspects of the usually complex design call for a mixed modelling approach taking into
account various sources of variation, e.g., incomplete blocks, a spatial error structure, genetic correlations due to the
pedigree, and random environmental effects, including QTL × E interaction. Perhaps the most important source of random variation
is the genetic correlation across environment, which arises when the same set of lines is tested in each environment. This
correlation is likely to be positive, and ignoring it will lead to an increased rate of false positives. In this paper, we
present a mixed modelling framework for QTL mapping based on complex data from multiple environments. Our main focus is on
an appropriate modelling for the non-QTL part. The methodology will be illustrated using a barley data set from a BC2F2:5 advanced backcross trial.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Nehemia Anthony Mashiringwani Kingstone Mashingaidze Josephine Kangai Klaus Olsen 《Euphytica》1994,76(1-2):33-44
Summary Grain filling rate in wheat (Triticum aestivum L. emend. Thell.) positively influences grain yield under a wide range of conditions. The effective utilization of this trait in breeding depends on an understanding of its genetic control. A study was, therefore, conducted to determine the genetic basis of grain filling rate in six crosses of wheat. Higher order genic interactions and/or linkage were important in the genetic regulation of grain filling rate (GFR) in the majority of crosses. Additive ([d]) and dominance ([h]) gene effects were important in the control of GFR in main ears (ME) and whole plant ears (WPE). Additive and additive × additive epistatic effects were the most important in the genetic control of GFR in last ears (LE). Location effects on genetic effects for GFR were significant (P < 0.05) in all ear types of some crosses except in ME. Genotype × environment interaction effects were important (P < 0.001) in LE and WPE.It was concluded that the inheritance of GFR is complex and is dependent on ear type. Breeding procedures that facilitate the exploitation of non-additive and additive gene effects were recommended for the genetic improvement of grain filling rate of wheat. 相似文献