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51.
Data from 19 Japanese Black multiparous cows were collected to clarify the relationships among immunoglobulin (Ig) G, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of cows in order to evaluate the role of fat‐soluble vitamins on colostral IgG and IgA production. Mean colostral IgG was 141 mg/mL, ranging from 65 to 208 mg/mL, whereas mean colostral IgA was 8.7 mg/mL, ranging from 1.0 to 34.6 mg/mL. Colostral IgG increased with aging in multiparous cows. There were positive correlations between colostral IgG and colostral vitamin A or colostral α‐tocopherol in cows, and the higher adjusted R2 was obtained in the prediction model of colostral IgG from age and colostral vitamin A. Colostral vitamin A was positively correlated with colostral β‐carotene or colostral α‐tocopherol in cows, but there were no relationships between colostral IgA and colostral IgG or colostral fat‐soluble vitamins. These results indicate that fat‐soluble vitamin contents in colostrum of cows may change in similar patterns and high colostral vitamin A is related with high colostral IgG.  相似文献   
52.
A comparison was made of the minimum inhibitory concentrations (MICs) of polyoxin B and iprodione against Alternaria mali, A. kikuchiana and Botrytis spp. isolalated from diseased plants from various regions of Japan. Several of these fungal isolates differ markedly in their sensitivity to iprodione and polyoxin B. A study was made of the relationship between the MIC values of polyoxin B and iprodione against several isolates and disease control obtained when these materials were applied to plants infected with the same isolates.  相似文献   
53.
A molecular survey of hemoplasma (Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum') in Yamaguchi Prefecture and surrounding areas was performed by using molecular methods. PCR-RFLP with HindIII revealed that 2 cats were infected with M. haemofelis, and 16 with 'C. Mycoplasma haemominutum' among 102 randomly selected cats. Partial 16S rRNA gene sequences of M. haemofelis and 'C. Mycoplasma haemominutum' determined in this study showed percent similarities of 98.3-99.8% and 96.4-100%, respectively, with those from other countries. Hemoplasma infections were more frequently detected in free-roaming cats than inside cats. Also, the status of FeLV infection was another significant risk factor for hemoplasma infection.  相似文献   
54.
Pestiviruses can be distinguished as two biotypes, cytopathogenic (cp) and noncytopathogenic (noncp), by the morphological changes that they induce during growth in cultured cells. In this study, the cp phenotype of several classical swine fever viruses (CSFV) was evaluated by the detections of the nonstructural proteins NS2-3 and NS3 using immunoprecipitation and Western blotting in different porcine cell lines. Most CSFVs that showed the exaltation of Newcastle disease virus (END) phenomenon (END(+) viruses) did not induce cytopathic effect (CPE) in any cell line, and detections of NS2-3 and NS3 showed a strong signal for NS2-3 in the END(+) virus-infected cells. However, clear CPE was observed in serum-free cultured cells (FS-L3 and CPK-NS) infected with viruses that induce intrinsic interference but did not show the END phenomenon (END(-) viruses), and signal of NS3 was strongly detected than that of NS2-3 in these cells at 72 hr after infection. As the results of the analysis of FS-L3 cells infected with ALD (END(+) virus) and ALD-END(-) virus (END(-) virus) at several incubations, the signal of NS3 detected was strengthened with CPE that become evident progressively. These results suggest that CPE is associated with the accumulation of NS3, which is promoted in serum-free cell lines infected with END(-) viruses. Thus, indicating there is a close relationship between CPE and the quantity of NS3 produced in END(-) CSFV infection.  相似文献   
55.
To assess possible adverse effects of residual chlorines from hypochlorite-treated seawater to non-target marine organisms, bioassays were carried out on marine amphipod Hyale barbicornis and estuarine fish Oryzias javanicus. Acute toxicity tests were first conducted using various concentrations of sodium hypochlorite (NaOCl) followed by a long-term exposure to residual chlorines from a test water treated with 1 mg L?1 NaOCl. Results showed that NaOCl was acutely toxic to both organisms. However, long-term exposure to residual chlorines from NaOCl-treated waters caused no major adverse effects to both organisms under laboratory conditions since free chlorines in the treated water was reduced to about 10% by 23-h holding and 1-h aeration. No H. barbicornis died but residual chlorine-exposed juveniles had significantly shorter body lengths at the end of exposure. Residual chlorine-exposed O. javanicus also showed no significant differences to that of the control in all measured endpoints except for hatching time. The results suggest that using 1 mg L?1 NaOCl for disinfection of ballast waters will produce residual chlorines that is far below the LC50 and EC50 of H. barbicornis and O. javanicus even on a long-term basis.  相似文献   
56.
Conversion of natural forests to other land use results not only in a decrease of forest area but also in the degradation of remnant forests as a habitat for forest animals. Although such degradation due to an increase of forest edges has been studied most intensively, other factors such as forest shape may also contribute to the degradation. In this study, we compared bird abundance and species richness between irregular-shaped and relatively continuous forests in the breeding and migratory seasons. Since the forests were surrounded by tree plantations rather than open lands, the edge effect may have been weak at the study site. Our results suggested that the irregular forest shape negatively affected forest bird abundance and species richness in the breeding season, but not in the migratory season. The response of birds varied with bird traits: migrants avoided the irregular-shaped forest, but residents did not. Among the residents, small ones preferred or tolerate the irregular-shaped forest whereas large ones avoided it. This study indicates that careful consideration of various factors such as seasonality and bird traits is needed to understand the consequences of land use changes on forest birds.  相似文献   
57.
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58.
The pathogenicity of Erysipelothrix tonsillarum was evaluated in pigs immunosuppressed with cyclophosphamide (CY) or dexamethasone (DM). Animals were treated with 15 mg/kg CY (n = 8, five injections), 1 mg/kg DM (n = 8, nine injections) or left untreated (n = 8). On the fifth day after the beginning of drug treatments, swine were inoculated with one of two E. tonsillarum serovar 7 strains (approximately 106 CFU per pig). In the CY-treated group, both circulating neutrophil and lymphocyte counts decreased, whereas in the DM-treated group, lymphocyte counts decreased but neutrophil counts increased. During the observation period, none of the CY- or DM-treated pigs developed clinical signs or gross lesions, as well as non-treated pigs. Growth agglutination antibody titres in all pigs remained unchanged. Our findings indicate that E. tonsillarum strains are avirulent for swine, regardless of immune status.  相似文献   
59.
The objective of the present study is to examine whether colostrum whey can have an effect on immune function in goats digestive tract. Two milliliters of colostrum whey (colostrum group) or water (control group) were administrated orally to goats every day for 3 weeks. Blood was collected twice a week for 3 weeks to measure immunoglobulin A (IgA), interleukin 8 (IL‐8), and IL‐10. At the end of the experimental period, the parotid glands, oral mucosa, lingua, esophagus, jejunum, and ileum were collected for immunohistochemical detection of IgA, cathelicidin‐7, and S100A8. The ratio of the length of IgA‐positive mucosal surface in the esophagus to the total esophageal length was significantly greater in the colostrum group than in the control group. The number of IgA‐positive cells in the labial gland and ileum in the colostrum group was significantly higher than that in the control group. There were no significant differences between the colostrum and control groups in the number of cathelicidin‐7‐positive cells in the jejunum and ileum and in the number of S100A8‐positive cells in the lingua, jejunum, and ileum. These results suggest that colostrum stimulates the recruitment of plasma cells into the labial gland, which then secrete more IgA into the saliva.  相似文献   
60.

Background

Plant roots release a variety of organic compounds into the soil which alter the physical, chemical and biological properties of the rhizosphere. Root exudates are technically challenging to measure in soil because roots are difficult to access and exudates can be bound by minerals or consumed by microorganisms. Exudates are easier to measure with hydroponically-grown plants but, even here, simple compounds such as sugars and organic acids can be rapidly assimilated by microorganisms. Sterile hydroponic systems avoid this shortcoming but it is very difficult to maintain sterility for long periods especially for larger crop species. As a consequence, studies often use small model species such as Arabidopsis to measure exudates or use seedlings of crop plants which only have immature roots systems.

Results

We developed a simple hydroponic system for cultivating large crop plants in sterile conditions for more than 30 days. Using this system wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) plants were grown in sterile conditions for 30 days by which time they had reached the six-leaf stage and developed mature root systems with seminal, nodal and lateral roots. To demonstrate the utility of this system we characterized the aluminium-activated exudation of malate from the major types of wheat roots for the first time. We found that all root types measured released malate but the amounts were two-fold greater from the seminal and nodal axile roots compared with the lateral roots. Additionally, we showed that this sterile growth system could be used to collect exudates from intact whole root systems of barley.

Conclusions

We developed a simple hydroponic system that enables cereal plants to be grown in sterile conditions for longer periods than previously recorded. Using this system we measured, for the first time, the aluminium-activated efflux of malate from the major types of wheat roots. We showed the system can also be used for collecting exudates from intact root systems of 30-day-old barley plants. This hydroponic system can be modified for various purposes. Importantly it enables the study of exudates from crop species with mature root systems.
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