The effect of supplementation of flax-seed oil on interaction of Lactobacillus plantarum--Biocenol™ LP96 and Escherichia coli O8:K88ab:H9 in the gut of germ-free piglets

We investigated the influence of administration of flax-seed oil on interaction of Lactobacillus plantarum – Biocenol? LP96 and Escherichia coli O8:K88ab:H9 in the gut of germ-free piglets. When compared to animals supplemented with L. plantarum, the counts of lactobacilli in the jejunal and ileal mucosa and in the intestinal content were significantly higher in LMK group (p < 0.0001). Inter-groups comparison of the counts of E. coli K88 adhering to the jejunal and ileal mucosa revealed a significantly decrease in LMK animals (p < 0.001; p < 0.05).     

Property of large conductance Ca(2+)-activated K+ channels from Fasciola hepatica incorporated into planar lipid bilayer

Fasciola hepatica causes biliary epithelial hyperplasia and obstructive jaundice in humans and animals. Using a planar lipid bilayer technique, we further characterized the single channel property of large conductance K(+)-permeable channels that were previously identified from F. hepatica. The single channel conductance was 254.7±17.9 pS under a symmetrical 200/200 mM (cis/trans) KCl gradient. Open state probability (P(o)) varied from channel to channel at a given membrane potential and Ca(2+) concentration, but increased with voltage (-60 to +40 mV) and cis Ca(2+) (1-200 μM). Under a near bi-ionic condition of 200 mM [K(+)](cis)/200 mM [Na(+)](trans), the permeability ratio of K(+) to Na(+) was 5.0. Charybdotoxin (1 μM) inhibited P(o), whereas tetraethylammonium reduced the conductance (K(D)=67.8mM). Taken together, the results show that the single channel properties of the large conductance K(+)-permeable channels in F. hepatica are similar to those of large conductance Ca(2+)-activated K(+) (BK) channels in general, but distinct from typical BK channels in the extent of voltage- and Ca(2+)-dependence, as well as permeability to Na(+). This study further reveals a variant BK channel in F. hepatica that could serve as a new drug target to treat fascioliasis.     

SRY-positive 78, XY ovotesticular disorder of sex development in a wolf cloned by nuclear transfer

Recently, we reported the three wolves cloning with normal karyotype from somatic cells of endangered male gray wolves (Canis lupus), but one wolf had female external genitalia. In this study, we conducted further clinical, histological, and genetic analyses. This cloned wolf had a normal uterus but developed ovotestis. Through molecular analysis of the SRY gene, a mutation in the coding sequence of SRY gene could be excluded as a cause of intersexuality. This is the first report of a cloned wolf with a 78, XY ovotesticular disorder affecting sexual development characterized by bilateral ovotestes.     

长期不同施肥条件下土壤微生物量及 土壤酶活性的季节变化特征

研究长期不同施肥条件下褐潮土微生物量碳（SMBC）、微生物量氮（SMBN）和土壤酶活性随季节的变化特征。结果表明,长期施肥条件下土壤SMBC、SMBN含量及土壤酶活性均表现出一定的季节变化。SMBC、SMBN含量在各施肥处理中的顺序为:化肥与猪厩肥配施处理（NPKM）化肥配施玉米秸秆处理（NPKS）单施化肥处理（NPK）不施肥处理（CK）,各处理之间差异显著(P0.05);施肥还显著提高了土壤脲酶、转化酶、碱性磷酸酶活性,有机无机配施的高于单施化肥的。除过氧化氢酶活性随季节变化显著下降外,SMBC、SMBN、酶活性的值一般在夏季（6月到8月）较高。通过双因素单变量方差分析表明,不同施肥制度与季节变化对SMBC、SMBN与酶活性的影响分别达极显著水平（P0.01）,不同施肥制度的SMBC、SMBN与酶活性的季节波动有极显著不同（P0.01）。     

Changes in the physicochemical and microbiological properties of dried anchovy <Emphasis Type="Italic">Engraulis japonicus</Emphasis> during storage

This study investigated the changes in the pH, thiobarbituric acid (TBA) value, volatile basic nitrogen (VBN), color L*, a*, b*, shear force, and microbial content (total plate count; TPC) of dried anchovy Engraulis japonicus in a home refrigerator and freezer at 2, ??1, ??5, and ??20 °C. The TBA value and shear force significantly decreased with increasing storage duration at all of the tested temperatures (p?<?0.05), whereas the VBN and TPC values increased (VBN significantly so) with increasing storage duration (p?<?0.05). The anchovy L* values decreased, whereas the a* (redness) and b* (yellowness) values increased as the storage period was lengthened. The pH decreased after 9 months. The results suggest that the optimum storage period of the dried anchovy is within 6 months. It can be stored below 2 °C for 3 months, but for storage exceeding 3 months, it should be frozen at ??5 °C.     

Evaluation of vaccine-induced maternal immunity against classical swine fever

The vaccine-induced maternal immunity against classical swine fever (CSF) was investigated in this study. Eight sows were vaccinated with the Chinese strain of classical swine fever virus (CSFV). The length of time between vaccination and farrowing was 167-217 days. Milk samples from the front, middle and back udder sections and blood samples were taken from the sows on days 3 and 14 after farrowing. Blood samples were obtained from the piglets at the age of 3, 6 and 10 weeks. The antibody level of the milk was examined by ELISA, and that of blood samples by the virus neutralization (VN) test as well. In all 3-week-old piglets and in 80% of the 6-week-old animals the neutralizing antibody level reached the titre of 1:40. In none of the 10-week-old piglets did the titre exceed the value of 1:20, but in about 25% of the piglets it reached 1:20; the half of these piglets came from two litters. In none of the piglets did the antibody level reach the negative threshold in the ELISA test during the study. No significant differences were found between the udder sections in milk antibody level by ELISA.     

Positive identification of Newcastle disease virus vaccine strains and detection of contamination in vaccine batches by restriction site analysis of the matrix protein gene

Twelve vaccine batches prepared from avirulent vaccine strains of Newcastle disease virus produced by seven manufacturers were identified by analysis of the matrix (M) protein gene with restriction enzymes MboI and HinfI. The analyses have revealed the presence of the strain indicated by the manufacturers (namely B-1, LaSota or Ulster 2C), except in one case when the vaccine contained strain V4 Queensland instead of VGGA as indicated. In addition, several batches of both monovalent and combined vaccines containing strain LaSota of the same company consistently disclosed contamination with strain B-1. The mixed nature of the preparations was verified not only by the dual patterns of restriction fragments but also by separating the two components and identifying them individually. Restriction analysis of the M gene, by allowing positive identification of each of the lentogenic vaccine strains, should provide an improvement in controlling vaccine batches by revealing homologous contaminants or exchange of the vaccine strain.     

Influence of pollination methods on fruit development and sugar contents of oriental melon (Cucumis melo L. cv. Sagyejeol-Ggul)

This study was conducted at the Seongju Fruit Vegetable Experiment Station for 2 years, 2002–2003 to investigate the effect of pollination methods on development and sugar content of oriental melon fruits. Oriental melon fruit was pollinated by honeybees (Apis indica) and bumblebees (Bombus ignitus) and fruit setting growth regulators was used as a control treatment. Fruits pollinated by honeybees and bumblebees has lesser length and width of fruit compared to the control. Pollinated by bumblebees increased hardness and soluble solids of fruits by 27% and 4–5% and that of honeybees increased hardness and soluble solids of fruits by 12% and 5–10% compared to the control, respectively. Fermented fruit ratio (%) of oriental melon fruit pollinated by honeybees, bumblebees, and growth regulator was 6.7%, 9.1%, and 28.1%, respectively. Glucose, fructose and sucrose contents of fruits by HPLC (high performance liquid chromatography) were very low throughout the ripening stage, but abruptly increased at harvesting stage. In fructose content of fruits, pollination of bumblebees and honeybees was higher by 9% and by 13% than those of control, respectively. The amount of total sugar content in fully ripen fruits of oriental melon was not different between the treatments (P > 0.05). Total sugar content (%) of fruits pollinated by bumblebees was slowly decreased until 15 days after storage compared to that of other treatment. For the low fermented fruit ratio (%) and slowly reduced total sugar content at storage of fruits, the pollination of bees was more useful than fruit setting growth regulators in early cultivation of oriental melon under plastic houses. The economic analysis according to the pollination method will be needed in the near future.     

Organotypic slice culture of the hypothalamic paraventricular nucleus of rat

Organotypic slice cultures have been developed as an alternative to acute brain slices because the neuronal viability and synaptic connectivity in these cultures can be preserved well for a prolonged period of time. This study evaluated a stationary organotypic slice culture developed for the hypothalamic paraventricular nucleus (PVN) of rat. The results showed that the slice cultures maintain the typical shape of the nucleus, the immunocytochemical signals for oxytocin, vasopressin, and corticotropin-releasing hormone, and the electrophysiological properties of PVN neurons for up to 3 weeks in vitro. The PVN neurons in the culture expressed the green fluorescent protein gene that had been delivered by the adenoviral vectors. The results indicate that the cultured slices preserve the properties of the PVN neurons, and can be used in longterm studies on these neurons in vitro.