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101.
The present study examined the effects of feeding order of grain and protein supplements on ruminal nitrogen (N) loss through the diurnal variation of ruminal ammonia N and urea N in the blood and milk of dairy cows. Three ruminally fistulated cows were used in a 3 × 3 Latin square arrangement of treatments; that is, grain supplement fed at the first feed and then the protein supplement at the second (GS‐1st), protein supplement fed first and then the grain supplement (PS‐1st), and the grain and protein supplements mixed and divided into equal portions fed at each supplement feeding time (GP‐mix). No differences in the lactation parameters were observed among the treatments. In GS‐1st treatment, the increase in the concentration of ruminal ammonia N was inhibited after feeding, and the concentration was lower (P < 0.05) than with the other treatments 1–2 h after basal feeding. The concentrations of urea N in the blood and milk with the GS‐1st treatment were the lowest of all treatments throughout the sampling times, and were lower (P < 0.05) than with the GP‐mix treatment except for blood levels 1 h after basal feeding. The results suggest that grain feeding before protein feeding can reduce ruminal N loss.  相似文献   
102.
Silicone tubes filled with estradiol‐17β (E2) or the xenestrogen, bisphenol A (BPA) were covered with a polyethylene tube and implanted into mice subcutaneously. The releasing patterns from the tube in vivo were obtained from the volume of estrogen remaining in the tube by measurement with high performance lipid chromatography. E2 in glycerol was released in a few days from a silicone tube, which was not covered with a polyethylene tube (Type A). However, E2 in sesame oil was released very slowly from the silicone tube covered with a polyethylene tube (Type B) and approximately 10% of E2 remained in the tube at 56 days after implantation into the mice. The mean linear regression equation for E2 was Y = 70.967 ? 1.2271X (R2 = 0.9268) and the quadratic regression equation was Y = 77.97 ? 2.2773X + 0.0194 × 2 (R2 = 0.9864). The remainder rate curves of E2 and BPA were not significantly different throughout the experimental period of 56 days. The Type B tube in the present experiment might be useful for long‐term administration of estrogens.  相似文献   
103.
Expression of 150 kda oxygen-regulated protein, ORP150, was examined in the atheromatous lesions on aortic valves in high-fat diet fed mice. Immunohistochemical staining revealed that ORP150 was expressed on the surface of plaque and was co-localized with phagocytes bearing Mac-3, a mouse macrophage differentiation antigen. These findings suggest that ORP150 is involved in the development of the atheromatous plaque. Titer of autoantibody against ORP150 was gradually elevated in parallel with the length of period of high-fat diet feeding. These results suggest that the deposition of immunocomplex toward ORP150 antigen is involved in atheromatous plaque progression.  相似文献   
104.
In 1996 and 1997, the seroprevalence against Leptospira in parturient sows with premature birth or stillbirth from two herds was investigated. In three out of four sow serum samples obtained in Gunma Prefecture, the antibody titers to Leptospira interrogans serovar copenhageni (M20) were higher than 10,000 (the reciprocal of the serum dilution). Furthermore, the antibody titers to L. interrogans serovar canicola (Hond Utrecht IV) were significantly high in the three sows and the titers ranged from 1,000 to 3,000. In sows obtained in Chiba Prefecture, significantly high antibody titers to serovar copenhageni (M20) were confirmed in eight out of 40 sows, and antibody titers greater than 10,000 in six of them. Significantly high antibody titers to L. interrogans serovar icterohaemorrhagiae (RGA) and L. canicola (Hond Utrecht IV) were confirmed in four and 18 out of the 40 sows, respectively, compared with the titers to the other serovars. These findings may indicate the prevalence of leptospirosis in pig herds in both Gunma and Chiba Prefectures.  相似文献   
105.
106.
The major causes of deforestation and degradation of natural resources in the Belete-Gera Forest of Ethiopia are coffee production activities and encroachment into forestland to expand farmland and pasture. Population growth, and the government’s land-reform and re-settlement programs have caused local residents to lose harmony with the land. Forest management in this area hasn’t yet been fully developed. The objectives of this study are to identify the extent of deforestation and natural resource degradation, in preparation for a sound management plan. Encroachment of farmland and pasture into natural forest during the past four years has been identified through interviews and aerial photo interpretation. The encroachment rate is 1.45% per year. Encroachment occurred mostly on areas with gentle slopes adjacent to populated villages and along roads and footpaths. The extent and impact of coffee production activities were examined through agency documents, forest survey data and vegetation survey. It is estimated that up to 49% of the accessible natural forest is under the influence of coffee production activities, among which collecting of naturally grown coffee beans has the least and the coffee plantations has the most impact on the natural forest. Coffee plantations in natural forest have reduced the forest density and species diversity. Age structure of the trees is limited to mature and old classes only, which eventually endangers their function as shade for coffee plantations. This project was funded by the Japan International Cooperation Agency.  相似文献   
107.
Trypsin from the pyloric ceca of masu salmon (Oncorhynchus masou) cultured in fresh water was purified by a series of chromatographies including Sephacryl S-200, Sephadex G-50 and diethylaminoethyl cellulose to obtain a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS–PAGE) and native PAGE. The molecular mass of the purified trypsin was estimated to be approximately 24,000 Da by SDS–PAGE. The enzyme activity was strongly inhibited by phenylmethylsulfonyl fluoride, soybean trypsin inhibitor, and N α -p-tosyl-l-lysine chloromethyl ketone. Masu salmon trypsin was stabilized by calcium ion. The optimum pH of the masu salmon trypsin was around pH 8.5, and the trypsin was unstable below pH 5.0. The optimum temperature of the masu salmon trypsin was around 60°C, and the trypsin was stable below 50°C, like temperate-zone and tropical-zone fish trypsins. The N-terminal 20 amino acid sequence of the masu salmon trypsin was IVGGYECKAYSQPHQVSLNS, and its charged amino acid content was lower than those of trypsins from frigid-zone fish and similar to those of trypsins from temperate-zone and tropical-zone fish. In the phylogenetic tree, the masu salmon trypsin was classified into the group of the temperate-zone fish trypsin.  相似文献   
108.
Morphological variation of the skull was examined in the northern treeshrew (Tupaia belangeri) from various localities across Southeast Asia. Through a multivariate analysis, the treeshrews from South Vietnam exhibited distinct morphological characteristics compared to other populations from Thailand and Laos, and Malaysia. The plots of the specimens of North Vietnam are not randomly mixed with Thailand plots segregation in the scatteregrams of canonical discriminant analysis. Since the skulls of the population from North Vietnam were morphologically similar to those form central Laos and northern and northeastern Thailand, the zoogeographical barrier effect of Mekong River was not clearly confirmed. The population of the Kanchanaburi in western Thailand is clearly smaller in size compared to the other populations. The southern border of the distribution of this species is determined by the Isthmus of Kra or Kangar-Pattani Line. In the northern treeshrew, which is distributed from southern China to Bangladesh and southern Thailand, we have detected osteometrical geographical variation driven by geography. These results indicate that the skull morphology in the Tupaia glis-belangeri complex distinctively differs in South Vietnam, western Thailand, and southern Thailand. The zoogeographical barrier and factor separating these districts are expected to clarify in the future.  相似文献   
109.
The occurrence of morphological deformities under different rearing water temperatures (18, 20, 22, 24, 26, 28, and 30 C) was examined in Japanese eel larvae. The rates of hatching and survival until yolk resorption at 22–26 C were higher than those at other water temperatures. Fertilized eggs never hatched at 18 and 30 C. The rates of occurrence of abnormal larvae reared at the water temperatures 24–28 C were lower than those at 20 or 22 C. Pericardial edema and lower jaw deformities occurred most frequently at lower temperatures (20 and 22 C). In contrast, the incubation temperature did not significantly affect the relative frequency of some neurocranial deformities and of spinal curvature. These results imply that the optimal temperatures for rearing Japanese eel eggs and embryos are 24–26 C from the viewpoints of survival and deformity.  相似文献   
110.
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