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61.
This paper investigates the effect of the introduction of an irrigation technique on the technical efficiency of olive production in a sample of olive-growing farms in Tunisia, estimating the Cobb-Douglas form of stochastic frontier production function. Results indicate that estimated technical efficiency scores vary, ranging from a minimum of 3.0% to a maximum of 91.2% with a mean value of 61.2%. This suggests that olive-growing farms in Tunisia can increase their production on average by 38.8% through more efficient use of technology and inputs. The introduction of irrigation increased productivity, however, the estimated technical efficiency of irrigated olive farms varies across farms and they are less efficient than non-irrigated farms. This finding suggests that the introduction of irrigation to non-irrigated farms has the potential to increase production levels, however, the current production of the irrigated farms is far from the "best practice frontier" that realizes maximum possible output. Accumulation of experience and knowledge by farm owners and selection of olive cultivar significantly contribute to improving technical efficiency.  相似文献   
62.
The prevalence of footpad dermatitis (FPD) in broiler chickens in Japan was investigated. In the first examination at slaughterhouses, lesions were commonly observed on the footpads of a total of 8,985 broiler chickens from 45 flocks on 36 farms. In 3 flocks, all the birds examined had lesions. In the other 42 flocks, the incidence of FPD ranged from 31.9% (81/254) to 99.5% (1/222). The footpad lesions were classified into 4 categories according to the severity of dermatitis as follows; score 0, 1,181 birds (13.1%); score 1, 2,992 birds (33.3%); score 2, 3,000 birds (33.4%); and score 3, 1,812 birds (20.2%). The mean scores of the flocks varied widely from 0.31 to 2.69. Males had higher mean scores than females. No significant differences were found between the mean scores of birds reared in windowless houses and those in open-sided houses. On 4 farms, the investigation was carried out in different seasons, and 3 of them showed higher mean scores in winter than in summer. Next, observation of 2,255 birds from 15 flocks on 5 farms during a 4-week rearing period revealed that FPD was already produced at 7 days of age and worsened with age.  相似文献   
63.
As IgE plays a pivotal role in type I hypersensitivity-mediated allergic diseases, it is valuable to measure absolute quantity of serum antigen-specific IgE for clinical and research purposes. Here we describe a novel ELISA system that enables quantification of antigen-specific IgE in ng/ml in dogs. A newly developed monoclonal antibody (CRE-DM) was shown to recognize canine and mouse IgE equally in a dose dependent manner, but it did not recognize canine IgG. The reactivity of CRE-DM to canine IgE was also confirmed by an inhibition ELISA using canine IgE as an inhibitor and the maximum inhibition rate was 91.3%. In order to know whether canine IgE specific to an allergen could be quantitatively measured with an ELISA using CRE-DM, we established a quantitative ELISA that could measure canine IgE recognizing Cry j 1, one of the major allergens of Japanese cedar pollen. In this ELISA, a standard curve was created by using concentration-predetermined Cry j 1-specific monoclonal mouse IgE. According to the standard curve, the concentration of Cry j 1-specific IgE in dogs that were experimentally sensitized to Japanese cedar pollen could be calculated and determined in ng/ml. The specificity of the Cry j 1-specific IgE ELISA using CRE-DM was also confirmed by inhibition ELISA using canine IgE as an inhibitor and the inhibition rate was 97.0%. Reproducibility of the ELISA in three independent assays was determined using groups of pooled canine sera whose Cry j 1-IgE titers ranged from 155.9 to 888.2 ng/ml. Intra- and inter-assay reproducibility was determined with coefficient of variation ranging between 3.1-5.2% and 2.2-8.0%, respectively. These results demonstrated that the ELISA utilizing CRE-DM was a specific, reliable and robust new laboratory test that could quantify absolute amount of antigen-specific IgE in canine serum. The ELISA will serve as a useful tool in the clinics to evaluate the change of serum IgE titers during anti-allergic treatments as well as during seasonal fluctuation of allergen exposure.  相似文献   
64.
Background: Bearded dragons are one of the most popular pet lizard species, and biochemical reference values are useful for health management of these reptiles. Objectives: The objectives of this study were to measure plasma biochemical values in healthy captive bearded dragons, determine reference values, and evaluate the effects of sex and season on the results. Methods: Blood samples were collected from 100 captive healthy bearded dragons in Tokyo during the summer and winter. Plasma biochemical measurements were performed using a dry‐slide automated biochemical analyzer. The data were then compared based on sex and season using 2‐way ANOVA. Results: Globulin, cholesterol, and calcium concentrations of females were higher in both summer and winter compared with the values obtained for males. Both males and females had higher uric acid concentrations in winter than in summer. When compared with males, females had a higher chloride concentration in summer and a higher total protein concentration and aspartate aminotransferase activity in winter. Potassium concentration in males was lower in winter than in summer, whereas in females cholesterol concentration was lower in winter than in summer. Conclusions: Biochemical values that differed based on sex and season in bearded dragons were similar to those in other lizards. These differences reflect physiologic differences in reproductive status in females and seasonal changes in temperature and hydration status. Plasma biochemical values established for bearded dragons in this study will be useful in the diagnostic assessment of captive animals.  相似文献   
65.
Paddy and Water Environment - The Mekong Delta produces 55% of Vietnam’s rice (Oryza sativa L.) through double or triple cropping each year. It accounts for a large proportion of...  相似文献   
66.
The Freundlich isotherm was used to estimate the adsorption of the herbicide linuron on 39 Japanese soils to confirm the suitability of the prediction technique used in atrazine adsorption. Linuron was adsorbed on the soils according to the Freundlich isotherm. In conjunction with the log K F prediction equation derived from the soil characteristics, it was possible to predict the linuron adsorption. Comparison of the equations for linuron with those for atrazine, indicated that the difference in the intercept of the 1 / n regression line against log K F reflected the adsorptive characteristics of the herbicides.  相似文献   
67.
To understand the organic sulfur (S) stabilization in volcanic soils, we investigated organic S transformation rates and their relationships to soil properties in incubation experiments using forest soils from the Nikko volcanic region, central Japan. We hypothesized that carbon (C)-bonded S would first be transformed into ester sulfate-S and then into inorganic sulfate-S. We separately calculated the rates of decrease of C-bonded S (velocity 1, v 1) and ester sulfate-S (velocity 2, v 2) concentrations. During incubation, the ester sulfate-S concentration increased in two soils characterized by a high concentration of both ammonium oxalate-extractable aluminum (Alo) and pyrophosphate-extractable Al (Alp), whereas the C-bonded S concentration decreased in all soils. A large proportion of the S that was lost in the incubation experiments consisted of C-bonded S rather than ester sulfate-S. Velocity 2 was negatively correlated with both of Alo and Alp contents when soils were incubated at 20 °C. These results suggest that when C-bonded S is transformed into ester sulfate-S, complete mineralization to inorganic sulfate is inhibited, because ester sulfate-S is stabilized due to organo–mineral association. Incubation temperatures significantly affected v 2. Thus, production of inorganic sulfate by mineralization of ester sulfate-S appeared to be regulated by soil Al contents and temperatures. Velocity 1 was proportional to soil pH ranging from 4.5 to 5.5, indicating that the degradation of C-bonded S is pH dependent.  相似文献   
68.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   
69.
The extracellular matrix surrounding the oocyte before ovulation is called the perivitelline membrane (PL) in avian species. The PL is constructed with two major glycoproteins, ZPC and ZP1, which are synthesized in the ovarian granulosa cells and the liver, respectively. Although the properties of the major components in the PL have been examined, knowledge about the nature of its minor constituents is lacking. In this study we focused on PL protein, which migrates at 46‐kDa in the gel of SDS‐PAGE. N‐terminal sequence analysis demonstrated that the 46‐kDa protein is the C‐terminal fragment of ZP1. Analysis of lysylendopeptidase digests or cyanogens bromide‐degraded fragments of ZP1 confirmed this postulate. Western blot analysis using antiserum against 46‐kDa protein indicated the absence of 46‐kDa protein in the serum. Moreover, small immunoreactive bands, thought to be cleaved fragments of ZP1, were detected in the PL lysate by western blot analysis using antiserum against the N‐terminal peptide of ZP1. These results indicated that the N‐terminal proteolytic processing of ZP1 might take place after the arrival of ZP1 at the ovary, and the resulting product, 46‐kDa protein, is incorporated into the PL.  相似文献   
70.

Abstracts from the Journal of Japanese Forestry Society

The original papers appeared in the Journal of Japanese Forestry Society vol. 86, no. 3 in Japanese with English abstracts  相似文献   
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