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81.
We assessed whether rolling damage by grazing horses could be reduced by constructing areas assigned for rolling. A group of horses were enclosed in a paddock with and without rolling areas made of dry soil, sand, and straw. Their behavior was recorded for 1 week in the paddock without any treatment (control paddock). Then the horses were moved to another paddock with the rolling areas (rolling paddock). After a 3-week familiarization period, horses were observed for 1 week. In the rolling paddock, the frequency and time spent rolling were significantly greater in rolling areas than in nonrolling areas. Horses significantly preferred the soil rolling area than sand and straw (P < .05). Although rolling was considered the most relevant body care behavioral element, the effects of the substrate in rolling areas on other body care behavioral activities, such as mutual and self-grooming, also were investigated. The frequency and duration of mutual grooming and the duration of self-grooming decreased significantly in the rolling paddock compared with the control paddock (P < .05). Hence, offering a rolling area encourages horses to roll in these areas and keeps the pasture in good condition; therefore, grazing time can be increased, with less reliance on supplementary feed.  相似文献   
82.
Nationwide seroprevalence of Neospora caninum among dairy cattle in Japan   总被引:3,自引:0,他引:3  
Serum samples from 2420 clinically healthy dairy cattle, randomly selected from stored sera in 18 districts of Japan, were tested for the presence of Neospora caninum antibodies using an indirect fluorescent antibody test (titer > or =1:200). Nationwide seroprevalence is estimated at 5.7% (139/2420). Seropositive cattle were detected in all surveyed districts despite the evidence of confirmed case reports of bovine neosporosis, showing that N. caninum is widely distributed throughout Japan. Age-specific seroprevalence did not increase with cattle age, suggesting that Neospora infection is likely to be transmitted vertically rather than horizontally in Japan. Considering that N. caninum seropositive cows are thought to be more likely to abort, substantial fetal losses may be induced by N. caninum infection in Japan. Devising strategies are needed to reduce the economic impact on the Japanese dairy industry. This is the first study to investigate the nationwide seroprevalence of N. caninum in cattle in Asia.  相似文献   
83.
Blooms of toxic dinoflagellates of the genus Ostreopsis, which is known as a producer of palytoxin (PTX) analogs, may pose a threat to human health in tropical, subtropical, and temperate regions around the world. In the present study, we established a suitable culture method for Ostreopsis spp. isolated from Japanese coastal waters and characterized their growth potential using the method to discuss their bloom dynamics. Each clonal strain of Ostreopsis cf. ovata, Ostreopsis sp.?1, Ostreopsis sp.?5, and Ostreopsis sp.?6 was incubated in 25?×?150?mm test tubes with a flat bottom containing various kinds of medium. Since Ostreopsis spp. strains grew well in IMK and/or f/2 media, we selected these media for cultivation of all the Ostreopsis spp. isolates. Growth rates of O. cf. ovata (0.834?divisions/day), Ostreopsis sp.?1 (0.619?divisions/day), and Ostreopsis sp.?6 (1.04?divisions/day) that produce PTX analogs significantly differed (p?<?0.05) respectively and are clearly higher than those of other reported epiphytic dinoflagellate Gambierdiscus toxicus, Prorocentrum lima, and Coolia monotis cultures, which suggest that these species have ecological advantages to predominate through the algal succession in Japanese coastal waters, resulting in a potential risk to human health in this region.  相似文献   
84.
兰州市南北两山的绿化是为当地居民营造良好居住环境的重要工作,该地区造林树种生长规律更是植被恢复中树种选择和抚育管理的依据。以2005年在兰州市甲子坪1号和2号试验地以及2006年在皋兰山试验地栽植的侧柏和山杏为对象,通过树高和胸径调查以及树干解析,对其生长特性进行研究。结果表明:在2014年调查时,甲子坪1号和2号试验地以及皋兰山试验地的侧柏平均树高分别为3.0 m、3.7 m和3.0 m,平均胸径分别为3.5 cm、5.2 cm和3.0 cm,侧柏的存活率为80%~88%,山杏的存活率达到80%以上。2008—2014年的3次调查结果表明,侧柏的树高平均增长量为0.15~0.18 m·a~(-1),山杏的树高平均增长量为0.17~0.20 m·a~(-1)。对侧柏优势木(树高4.5 m)、平均木(树高3.5 m)和劣势木(树高2.8 m)的树干解析得出,侧柏苗期(栽植后3 a)的高生长速率为0.3~0.4 m·a~(-1),个体间没有显著差异,但造林3 a后优势木的高生长速率为0.2~0.4 m·a~(-1)、平均木为0.2 m·a~(-1)、劣势木为0.1~0.2 m·a~(-1),个体间差异显著。  相似文献   
85.
Epigenetic abnormalities in cloned animals are caused by incomplete reprogramming of the donor nucleus during the nuclear transfer step (first reprogramming). However, during the second reprogramming step that occurs only in the germline cells, epigenetic errors not corrected during the first step are repaired. Consequently, epigenetic abnormalities in the somatic cells of cloned animals should be erased in their spermatozoa or oocytes. This is supported by the fact that offspring from cloned animals do not exhibit defects at birth or during postnatal development. To test this hypothesis in cloned cattle, we compared the DNA methylation level of two imprinted genes (H19 and PEG3) and three non‐imprinted genes (XIST, OCT4 and NANOG) and two repetitive elements (Satellite I and Satellite II) in blood and sperm DNAs from cloned and non‐cloned bulls. We found no differences between cloned and non‐cloned bulls. We also analyzed the DNA methylation levels of four repetitive elements (Satellite I, Satellite II, Alpha‐satellite and Art2) in oocytes recovered from cloned and non‐cloned cows. Again, no significant differences were observed between clones and non‐clones. These results suggested that imprinted and non‐imprinted genes and repetitive elements were properly reprogramed during gametogenesis in cloned cattle; therefore, they contributed to the soundness of cloned cattle offspring.  相似文献   
86.
In the lactic acid bacteria (LAB) strains screened from our LAB collection, Lactobacillus (L.) sakei strain no. 23 and L. curvatus strain no. 28 degraded meat protein and tolerated salt and nitrite in vitro. Fermented sausages inoculated strains no. 23 and no. 28 showed not only favorable increases in viable LAB counts and reduced pH, but also the degradation of meat protein. The sausages fermented with these strains showed significantly higher antioxidant activity than those without LAB or fermented by each LAB type strain. Angiotensin‐I‐converting‐enzyme (ACE) inhibitory activity was also significantly higher in the sausages fermented with strain no. 23 than in those fermented with the type strain. Higher ACE inhibitory activity was also observed in the sausages fermented with strain no. 28, but did not differ significantly from those with the type strain. An analysis of the proteolysis and degradation products formed by each LAB in sausages suggested that those bioactivities yielded fermentation products such as peptides. Therefore, LAB starters that can adequately ferment meat, such as strains no. 23 and no. 28, should contribute to the production of bioactive compounds in meat products.  相似文献   
87.
Four Thai native steers were used to determine the adequate levels of supplementary desalted mother liquor (DML) for energy and nitrogen balances and ruminal fermentation. The crude protein and sodium chloride contents of DML were 25.5% and 60.3% on a dry matter (DM) basis, respectively. A 4 × 4 Latin square design experiment was conducted by adding different amounts of DML to three experimental diets (T1: 1.1%, T2: 2.2%, T3: 3.4% sodium chloride concentration with supplementary DML on a DM basis) and comparing their effects with those of a control diet (C) containing 1.0% commercial salt on a DM basis. The animals were given the experimental diets and rice straw daily at 1.2% and 0.8% of body weight, respectively, on a DM basis. No significant differences in the apparent digestibility of nutrients were observed among treatments. T3 achieved the lowest nitrogen retention (< 0.05), followed by C, T2 and T1. The ratios of energy retention to gross energy were higher in T1 and T3 than T2, and that in C was lowest (< 0.05). Supplementary NaCl concentration at 1% and 2% can be replaced with DML without an adverse effect on the digestibility of nutrients or on the nitrogen and energy retention.  相似文献   
88.
Thelephora aurantiotincta is an edible mushroom belonging to the genus Thelephora; it grows in symbiosis with pine trees. Recently, phytochemical investigations have revealed that the genus Thelephora is an abundant source of p-terphenyl derivatives. However, their bioactivity has not yet been well characterized. In screening for natural materials with anticancer activity, a T. aurantiotincta ethanol extract (TAE) was found to decrease cell viability in human hepatocellular carcinoma cells (HepG2). In this study, a new p-terphenyl derivative, thelephantin O, and a known compound, vialinin A, were isolated as the principal bioactive components of TAE. These compounds decreased cell viability in HepG2 and human colonic carcinoma cells (Caco2), but not in noncancerous human hepatocytes. This is the first report of the isolation from T. aurantiotincta of selective cytotoxic agents against cancer cells.  相似文献   
89.
This study aimed to investigate the effects of whey protein hydrolysate (WPH) on the growth and immunity of mouse pups in artificial rearing (AR) system. Mouse pups were reared in the AR system with artificial milk including 5% WPH (AR with WPH) or not (AR without WPH), and the remaining pups were reared by their mother (dam) for 14 days after birth. The body weight change and body weight gain rates in the AR with WPH group were significantly higher than those observed in the AR without WPH group and similar to those in the dam group. Moreover the feed and protein efficiencies in the AR with WPH group were significantly higher than those of the AR without WPH group. In addition, the supplement of WPH in the AR system was shown to significantly elevate the number of CD3+CD8+, B220+CD19+, IA/IE+CD11c+, and CD11b+ in the thymocyte and/or splenocyte, and the thymus weight. Furthermore, MALDI‐TOF/MS analysis identified the amino acid sequences corresponding to some peptides, and indicated that VRTPEVDDE had the highest relative intensity among the peptides from tested WPH. Therefore, WPH would be required to not only promote growth, but also exert immunomodulatory activities in mouse pups in AR system.  相似文献   
90.
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