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31.
    
Strategies of Newcastle disease (ND) vaccination were demonstrated in a commercial ostrich farm in Japan. Three of 13 seven-month-old ostriches kept in a pen were vaccinated with a live ND vaccine by eye dropping for the 1st and 2nd vaccinations and spraying for the 3rd to 5th vaccinations. Antibodies against ND virus (NDV) were detected in all of the unvaccinated ostriches by virus neutralization test. At 2.5 months post final vaccination, 2 ostriches introduced into the pen raised antibodies against NDV. These data indicate that NDV may be transmitted from vaccinated to unvaccinated ostriches in the flock and that the virus may be sustained for a certain period in the flock. These data may be helpful for ND vaccination management in ostrich farms.  相似文献   
32.
The pharmacokinetics of oxolinic acid and oxytetracycline were examined in kuruma shrimp (Penaeus japonicus) after intra-sinus (10 and 25 mg/kg, respectively) and oral (50 mg/kg) administration. The shrimp were kept in tanks with recirculated artificial seawater at a salinity of 22–23 ppt. The water temperature was maintained at 25±0.6 °C. The hemolymph concentrations of both drugs after intra-sinus dosing were best described by a two-compartment open model. The distribution and elimination half-lives (t1/2 and t1/2β) were found to be 0.59 and 33.2 h for oxolinic acid and 0.45 and 24.7 h for oxytetracycline, respectively. The apparent volume of distribution at a steady state (Vss) and total body clearance (CLb) were estimated to be 1309 ml/kg and 28.8 ml/kg/h for oxolinic acid and 748 ml/kg and 22.7 ml/kg/h, respectively. The hemolymph concentration–time curves after oral administration did not fit by the nonlinear least squares method using one- and two-compartment model with first-order absorption in either of the drugs. The peak hemolymph concentration (Cmax), the time to peak hemolymph concentration (tmax) and the elimination half-life were found to be 17.8 μg/ml, 7 h and 34.3 h for oxolinic acid and 24.3 μg/ml, 10 h and 33.6 h for oxytetracycline, respectively. The bioavailability (F) after oral administration was 32.9% for oxolinic acid and 43.2% for oxytetracycline. The hemolymph protein binding in vivo was determined to be 36.7±8.5% for oxolinic acid and 22.9±4.8% for oxytetracycline.  相似文献   
33.
Although color Doppler ultrasonography has been used to evaluate testicular blood flow in many species, very little has been done in goat. Eight male Shiba goats were exposed to a single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1 µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW). Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr) and at different intervals post injection by radioimmunoassay. Testis volume (TV) and Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the supratesticular artery, were measured by B-mode and color Doppler ultrasonography, respectively. The results indicated an increase in testicular blood flow in both groups, as RI and PI decreased significantly (P<0.05), but this increase was significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant (P<0.05) correlation was found between E2 and both RI (r= −0.610) and PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG and GnRH may improve testicular blood flow and TV in Shiba goats.  相似文献   
34.
    
After improvement of hygiene protocols on boots in a bovine operation (farm A) in Ibaraki, Japan in September 2017, mortality of calves and the detection of 4 viral pathogen indicators, including bovine rotavirus A (RVA), became significantly low for one year. Subsequently, in the present study, these indicators and mortality were monitored and confirmed all were still low, except for the detection rate of bovine RVA in calves less than 3 weeks old. The present study aimed to investigate G and P genotypic profiles of RVAs in farm A from 2018 to 2020. Molecular analysis using semi-nested multiplex RT-PCR of positive RVAs (n=122) and sequencing of selected samples revealed the presence of G6, G8, G10, P[1], P[5] and P[11] genotypes and the prevalence of G and/or P combination and mixed infections. The most common combination of G and P types was G10P[11] (41.8%), followed by mixed infection with G6+G10P[5] (11.5%). Phylogenetic analysis of RVAs showed clustering with bovine and other animal-derived RVA strains, suggesting the possibility of multiple reassortant events with strains of bovine and others animal origins. Noteworthy as well is that vaccinated cattle might fail to provide their offspring with maternal immunity against RVA infections, due to insufficient colostrum feeding. Our findings further highlight the importance of RVA surveillance in bovine populations, which may be useful to improving effective routine vaccination and hygiene practices on bovine farms.  相似文献   
35.
大型灌区管理信息系统的建立   总被引:3,自引:0,他引:3  
介绍了大型灌区管理信息系统。该系统有 6大功能模块 ,除对数据库有维护基本功能外 ,还具有对灌区信息动态查询排序、统计分析功能 ,并以多种形式输出信息。该系统的建立为有关部门及时了解大型灌区工程及管理现状 ,制定宏观决策提供了有效的工具  相似文献   
36.
    
The abundance of Picea jezoensis, a major conifer tree species in Hokkaido, northern Japan, is currently decreasing due to the lack of suitable conditions for recruitment and intensive harvests. To contribute to the development of sustainable forest management in Hokkaido, suitable substrates for natural regeneration of P. jezoensis were evaluated during a 4-year experimental study using seed additions in a natural coniferous forest. The environmental conditions (moss height, log hardness, extent of the humus layer, and light conditions) of fallen logs were measured. Moss height was categorized into three groups: 0 mm, Bark; 0–20 mm, Mthin; and ≥20 mm, Mthick. The germination rates of P. jezoensis were highest on Mthin, intermediate on Bark, and lowest on Mthick. Survival rates were low on Mthick, did not differ between Bark and Mthin, and increased with enhanced light. Growth increased with light, but the root allocation of seedlings was not affected by any environmental conditions. From these results, we determined that fallen logs with no or thin moss cover under bright conditions were most suitable for P. jezoensis regeneration. We discuss the generality of our results in relation to a co-occurring tree species in Hokkaido and the results of other regions.  相似文献   
37.
Fuzzy linear regression (FLR) has been applied in many areas, including several areas of engineering. For instance, it has been successfully applied in conceptual rainfall runoff modeling to identify the parameters of the storage function (SF) model. In the FLR, each model parameter is not a crisp value as found in traditional procedures but the model parameters have a fuzziness value characterized by the center () and the width (c) values. The width value could be further analyzed in terms of its contribution in the prediction accuracy. In this case, the vagueness ratio, defined as a ratio between the width value and its center value for the model parameters, is presented here as a surrogate for analyzing any possible relation to the prediction accuracy. Application of the vagueness ratio to a number of flood hydrographs at Ochohzu basin in Fukuoka, Japan, shows that the ratio is useful for assessing the accuracy of the hydrograph prediction; i.e., the higher the value of the ratio indicates the less accuracy in the prediction.  相似文献   
38.
We describe here the detection by fluorescence of a new photosensitizer, PAD-S31, in tumours in dogs and cats and the effect of photodynamic therapy (PDT) by using PAD-S31 for skin tumours in two dogs and one cat. PAD-S31 is a hydrophilic photosensitizer that has two peaks at absorption wavelengths 406 and 665 nm in distilled water. In a preliminary experiment in mice transplanted with SCCVII and colon 26, PAD-S31 was retained in tumour tissues rather than in other organs. The tumours resected from dogs and cats after intravenous administration of PAD-S31 at a dose of 15 mg/kg emitted strong red fluorescence under light illumination of 402 nm wavelength. Animals given PAD-S31 showed no cutaneous photosensitivity under room light illumination. Irradiation at laser light 670 nm wavelength (fluence rate 150 mW/cm2 and total light dosage 150 J/cm2) on cutaneous mast cell tumours in dogs ( n=2 ) and a cutaneous basal cell tumour in a cat induced complete remission. These results suggest PAD-S31 could be a promising photosensitizer for use in a small animal veterinary practice.  相似文献   
39.
    
The mithun (Bos frontalis), synonymous with mithan and gayal, is considered to be a domesticated form of gaur (B. gaurus). However, there has been a controversy concerning its origin. In an effort to address this issue, the mitochondrial cytochrome b (cytb) genes of 20 mithun from Myanmar and 13 from Bhutan were sequenced to trace its maternal origin. Seven cytb haplotypes were found in the 33 mithun, and the phylogenetic tree for these haplotypes clearly showed three embranchments involving five gaur types, a B. indicus type, and a B. taurus type. Sixteen Myanmar and 12 Bhutan mithun had gaur haplotypes, while a B. indicus haplotype was found in three Myanmar and one Bhutan mithun. The B. taurus haplotype was detected in a single Myanmar animal. These results demonstrated that the principal maternal origin of mithun was gaur and suggested that it was directly domesticated from gaur. However, some introgression of domestic cattle existed in current mithun populations. The presence of cattle mtDNA raised the question of how many cattle nuclear genes might have been integrated into the gene pool of mithun.  相似文献   
40.
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