血管内皮生长因子对日本和牛胚胎卵裂率和4～8细胞期发育率的影响

为了探明血管内皮生长因子对IVM/IVF/IVC生产的日本和牛胚胎的卵裂率和到 4～ 8细胞期胚胎发育率的作用 ,在IVM/IVF/IVC的过程中 ,分别在SOF成熟液、BO液以及SOF培养液中添加 0、0 .1、1、10ng/ml的VEGF。通过对5 33个胚胎的检测得出 ,添加VEGF对胚胎卵裂率和 4～ 8细胞期发育率有促进作用 ,其卵裂率分别从对照的 4 7.3%提高到 5 1.4 % (0 .1ng/ml,P >0 .0 5 )、72 .6 0 % (1ng/ml,P <0 .0 5 )和 6 8.5 % (10ng/ml,P <0 .0 5 ) ;4～ 8细胞期发育率则分别从32 .0 %提高到 36 .4 %、5 9.7% (P <0 .0 5 )、5 2 .9%。结果证明 :VEGF对IVM/IVF/IVC的日本和牛胚胎发育有积极的促进作用。可以提高胚胎的卵裂率和 4～ 8细胞期胚胎发育率 ,这与作者前期从荷斯坦牛上得到的试验结果一致     

In situ ruminal degradation and in vitro fermentation characteristics,and antioxidative activities of the lotus rhizome

We evaluated the lotus rhizome as a potential ruminant feed by investigating its compositional properties, in situ degradation profile and in vitro fermentation characteristics with ruminal microbes, in comparison with cereal grains (corn, barley and wheat). The antioxidative activities in the lotus rhizome were also estimated. The soluble fraction of dry matter in lotus tuber was >70%, which was higher than those in the grains. The insoluble fraction in lotus tuber was not degraded by ruminal microbes in accord with a first‐order reaction. In an in vitro experiment, lotus tuber showed lower fermentation at 8 hr compared to the grains, but exhibited higher productions of gas and VFA at 48 hr along with a lower lactate and higher pH. The lower value of final lactate production in lotus tuber, indicating the metabolic capacity for lactate utilization retained, suggests a lower risk of ruminal acidosis compared to grains. Lotus rhizome had high antioxidant activities, with the foliar bud showing the strongest ferric reducing antioxidant power, followed in order by the apical bud, node, residual tuber, edible tuber, and nodal root. For ruminants, the lotus rhizome could thus be not only an energy feed but also the source of natural antioxidants.     

Drug resistance mechanism of the fish-pathogenic bacterium Lactococcus garvieae

The minimum inhibitory concentrations (MICs) of 15 chemotherapeutic agents were tested against 146 Lactococcus garvieae strains isolated from 1999 to 2006 in Japan. The agents used included chloramphenicol, ciprofloxacin, erythromycin (EM), enoxacin, fleroxacin, florfenicol, kanamycin, lincomycin (LCM), norfloxacin, oxolinic acid, orbifloxacin, ofloxacin, benzylpenicillin, streptomycin and tetracycline (TC). Of the tested strains, 46 showed high levels of resistance to EM, LCM and TC. Twelve of these strains were detected to be carrying transferable R-plasmids using a conjugation experiment and, using Southern hybridization, were shown to have the same structure as the R-plasmid. The remaining 34 resistant strains had a similar DNA structure to that of the R-plasmid as confirmed by polymerase chain reaction (PCR) using primers designed from sites in the transferable R-plasmid. The EM and TC resistance genes were classified into the ermB and tetS groups using PCR. We also detected gyrA and/or parC mutants that are highly resistant to old and new generation quinolones. This study revealed that transferable R-plasmids encoding EM, LCM and TC are widely distributed and are conserved regardless of the area and/or time of collection.     

何心隐的"不落意气"之论

宋明理学者不例外地认为豪杰不如圣贤.何心隐倒很拥护豪杰.他同时代人当中,王畿和其它心学者最严格地批评豪杰.他们认为因豪杰心里有意气妨碍心之本体的活动,所以学者必须得扫荡自己心里的意气.何心隐认为圣贤的意气和豪杰的意气没有道德价值上的差别.他很拥护个人有意志采取主体行动,歌颂个人行动的自由.     

Availability of genetically modified soybean meal in rainbow trout Oncorhynchus mykiss diets

The use of genetically modified defatted soybean meal (GM SBM) as rainbow trout feed was investigated, in comparison with non-GM SBM. Both SBMs were included at levels of approximately 15 and 30% in four diets (42% protein). The diets were fed to juvenile fish (48.3 g average weight) for 12 weeks. The nutrient use showed that there was no significant difference in growth and feed performance between GM and non-GM SBM groups at both inclusion levels at the end of 12th week. The cauliflower mosaic virus 35S promoter fragment (220 bp) of the GM SBM was detected in the muscle of fish receiving both levels of GM SBM diet by nested PCR, but the frequency of detection was greater at the higher inclusion level. Additionally, the promoter fragment was not detected by the fifth day after changing the diet to non-GM. Conversely, the promoter fragment was not detected from fish fed with the non-GM SBM diet. The results demonstrated that the availability of protein in GM SBM was similar to that of non-GM SBM, and the promoter fragments found in the muscle of fish were not detectable after changing the diet to non-GM, verifying the availability of the GM SBM in rainbow trout feed.     

Quality evaluation of different types of non-fish meal diets for yellowtail

SUMMARY: Two feeding experiments were conducted to evaluate the feed quality of non-fish meal diets having the same protein ingredient composition but prepared as different types, and to determine the supplemental effect of crystalline essential amino acids (EAA) on feed utilization by young yellowtail, Seriola quinqueradiata . Non-fish meal diets formulated with soy protein concentrate, defatted soybean meal, corn gluten meal, meat meal, and krill meal were prepared as either soft dry pellets (SDP) or extruded pellets (EP) by using a large- or a small-sized twin screw extruder under different preparation conditions; or as a single moist pellet (SMP), each with and without EAA mixtures. Commercial yellowtail SDP was used as the control diet. Fish weighing 134 g and 237 g on average were reared with the experimental diets, for 93 (net cages) and 44 (aquariums) days, respectively. The fish fed both the control and test diets were found to have a good appetite. Growth rate and feed gain ratio were highest in the control diet group. The physiological condition of fish fed the control diet was evaluated as superior compared to those on the non-fish meal diets. Among the non-fish meal diet groups, the best performances were obtained for fish fed the SDP type diet with EAA supplement, and performance parameters excelled in the order of SDP, EP and SMP both among the diets with and without supplemental EAA. This suggests that the nutritional quality of non-fish meal diet was affected by the diet preparation method. It also indicates that supplementation of EAA could improve the quality of non-fish meal diets, irrespective of the diet type, probably as a result from the enhancement of feed protein utilization.     

Various species of Pyricularia constitute a robust clade distinct from Magnaporthe salvinii and its relatives in Magnaporthaceae

In a phylogenetic analysis of species of Magnaporthaceae based on nucleotide sequences of rDNA-ITS and the RPB1 gene, isolates of the tested species were divided into two clusters with high bootstrap support. One group was composed of Pyricularia spp.; the other was composed of Magnaporthe salvinii, M. rhizophila, M. poae, Gaeumannomyces graminis, and G. incrustans. On the basis of this result, we concluded that Pyricularia spp. constitute a large but distinct phylogenetic species group that is not congeneric with Magnaporthe salvinii, the type species of Magnaporthe.     

Effect of inorganic ions on bud cell formation by <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> in potato dextrose broth

Potato dextrose broth (PDB), a well-known medium for cultivation of fungi, can be made from potato extract and glucose (handmade PDB) or bought as a commercial powder (commercial PDB). Previously, we reported that bud cell formation and fungal biomass of Fusarium oxysporum in handmade PDB are higher than in commercial PDB, and the presence of high molecular weight (>20 MDa) carbohydrates in PDB promoted bud cell formation by most strains of F. oxysporum. In this study, we report the effects of inorganic ions in PDB on bud cell formation and fungal biomass production by F. oxysporum. Concentrations of Mg, K, Fe, PO₄ ³⁻ and SO₄ ²⁻ were higher and of Na and Cl⁻ were lower in handmade PDB than in commercial PDB. Adding each inorganic ion alone to commercial PDB showed that Mg is critical for enhancement of bud cell formation by some strains of F. oxysporum. The addition of Mg²⁺ with raw potato starch to commercial PDB promoted bud cell formation by some, but not all, of the seven F. oxysporum strains tested in this study.