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121.
The effects of continuous stray voltage were evaluated on growing-finishing pigs between the ages of 8 and 21 weeks. Seventy-two pigs were assigned to six blocks of 12 animals each. The following treatments were randomly distributed in each block according to a 2 x 3 factorial design: feeding level (restricted or ad libitum) and voltage level (0, 2 or 5 volts (V) as a difference of potential between feeder or drinker and the metallic floor). During daytime, stray voltage at 5 V decreased (p less than 0.05) the eating frequency in both feeding groups and the drinking frequency in restricted-fed pigs. The mean duration of drinking bouts and the total time spent at the drinker were also lower (p less than 0.05) in this last group during the hour following meal distribution. Daily feed intake and average daily gain were lower (p less than 0.05 and less than or equal to 0.08, respectively) in the 5 V group than in the 2 V and the control groups from 17 to 21 weeks of age. Finally, gastric lesions, hematological and biochemical variables were not affected (p greater than 0.05) by stray voltage.  相似文献   
122.
Two anasarcous foetuses of Awassi sheep are described. The foetuses were removed from the dams by caesarean section because of dystocia due to failure of cervical dilation. Uterine incision was made in situ because uteri were so distended they could not be brought out from the site of incision. Large quantities of uterine fluids and abnormal thick placentas were found. One foetus weighed about 7 kg and the other 13 kg. The foetal heads were deformed: the upper jaw was prognathic and the left ear of the small foetus was cystic. Necropsy revealed subcutaneous musculature was soft and flabby and abdominal and thoracic cavities contained serosanguinous fluid. Histopathological examination revealed that only the larger foetus had focal aggregates of basophilic nucleated red blood cells and scattered megakaryocytes in the liver. We conclude that anasarca can occur in Awassi sheep, with and without associated extramedullary haematopoiesis.  相似文献   
123.
In this study, we selected 180 accessions from different wild relatives of wheat (AegilopsTriticum species) and tested them in the presence of a tolerant and a sensitive control variety under well-watered and drought-stressed conditions. The results of analysis of variance for dry masses and all measured root traits showed that water regimes, accession and species main effects were highly significant. Drought stress significantly declined shoot dry mass (59.42%), root length (37.85%) and the total number of branch roots (36.25%), but increased the root-to-shoot ratio (75.00%), specific root length (64.19%) and root tissue density (29.46%). Principal component analysis for 182 individuals and 12 species groups identified two components that explained 75.67 and 82.39% of the total variation in dry mass and root traits under drought-stressed conditions, respectively. Taking together, our results identified 12 accessions with superior tolerance to drought stress. Remarkably, four species of wild relatives – Ae. cylindrica (DC genome), Ae. neglecta (UM genome), Ae. speltoides (B genome) and Ae. tauschii (D genome) – responded well to drought stress. The potential of these species could be used for molecular analysis such as marker assisted selection and gene mapping, ultimately aimed at breeding for root traits with improved adaptation to drought environments.  相似文献   
124.
Lower Cretaceous bulk carbonate from deep sea sediments records sudden inputs of strontium resulting from the exposure of continental shelves. Strontium data from an interval spanning 7 million years in the Berriasian-Valanginian imply that global sea level fluctuated about 50 meters over time scales of 200,000 to 500,000 years, which is in agreement with the Exxon sea level curve. Oxygen isotope measurements indicate that the growth of continental ice sheets caused these rapid sea level changes. If glaciation caused all the rapid sea level changes in the Cretaceous that are indicated by the Exxon curve, then an Antarctic ice sheet may have existed despite overall climatic warmth.  相似文献   
125.
[目的]分析利比亚WadiBay干谷地区地下水水化学特征的形成原因,为地下水资源合理开发利用以及地下水环境保护提供科学依据。[方法]以利比亚Wadi 8Bay(Bay干谷)地区为例,运用Piper三线图示法、描述性统计、离子比例系数法、同位素证据,系统研究了利比亚WadiBay地区干旱气候条件下浅层地下水特殊的水化学特征。[结果]区域地下水含盐量很高,矿化度(TDS)在3.2~8.4g/L,地下水类型主要为Cl、SO4--Na、Ca,其次为Cl.SO4-Na、Ca、Mg;地下水中Cl-、Na+、SO42-等在距海70km处浓度产生突变,而Mn2+、Ba2+、Si2+、NH4+与NO3-并无同样突变现象。[结论]比亚WadiBay干谷地区浅层地下水水化学特征与溶虑作用、蒸发浓缩作用以及人类活动关系不大,主要成因为海水入侵过程中的咸淡水混合作用。  相似文献   
126.
Abstract

AIMS: To obtain information and compare the prevalence of Chlamydiaceae in riverine buffalo (Bubalus bubalis) and cows (Bos taurus) in Egypt with and without clinical signs of reproductive disease.

METHODS: Vaginal swabs and blood samples were collected from animals attending Governmental Veterinary Clinics without (buffalo n=39, cows n=20) and with (buffalo n=63, cows n=53) signs of reproductive disease. Serum samples were tested for antibodies to Chlamydiaceae using complement fixation testing (CFT). Vaginal swabs were tested for Chlamydiaceae following inoculation into Vero cells and 6-day-old embryonated chicken eggs, using modified Giménez and immunoperoxidase staining, PCR analyses targeting the omp2 gene, and Restriction Fragment Length Polymorphism PCR (RFLP-PCR) for species identification.

RESULTS: Antibodies to Chlamydiaceae were detected in 30/39 (77%) and 50/63 (79%) buffalo without and with signs of reproductive disease, respectively, and 10/20 (50%) and 39/53 (74%) of cows with and without signs of reproductive disease, respectively. Positive samples from PCR analysis were identified in 31/39 (79%) and 37/63 (59%) buffalo without and with signs of reproductive disease, respectively, and 12/20 (60%) and 46/53 (89%) of cows without and with signs of reproductive disease, respectively. Using RFLP-PCR, 57/68 (84%) of samples from buffalo, and 47/58 (81%) from cows, were identified as Chlamydophila psittaci and the reminder as Cp. abortus. From the CFT and PCR results there was no significant difference in the prevalence of positive samples between species, or between animals without or with signs of reproductive disease.

CONCLUSION: The presence of anti-Chlamydiaceae antibodies in 77% of the animals with signs of reproductive disease and the detection of Chlamydiaceae in 72% of vaginal swabs of the animals suggest a pathogenic role by Chlamydiaceae in riverine buffalo and cows. The main Chlamydiaceae found in the genital tract of cattle in Egypt were Cp. psittaci and Cp. abortus.

CLINICAL RELEVANCE: Chlamydophila spp. should be included in diagnostic algorithms for reproductive disorders, in order to assess the real burden of Chlamydophila associated disease in buffalo and cattle and to evaluate the potential value of vaccines.  相似文献   
127.
128.
The energetic particles investigation carried by the Galileo probe measured the energy and angular distributions of the high-energy particles from near the orbit of Io to probe entry into the jovian atmosphere. Jupiter's inner radiation region had extremely large fluxes of energetic electrons and protons; intensities peaked at approximately2.2RJ (where RJ is the radius of Jupiter). Absorption of the measured particles was found near the outer edge of the bright dust ring. The instrument measured intense fluxes of high-energy helium ions (approximately62 megaelectron volts per nucleon) that peaked at approximately1.5RJ inside the bright dust ring. The abundances of all particle species decreased sharply at approximately1.35RJ; this decrease defines the innermost edge of the equatorial jovian radiation.  相似文献   
129.
Neospora caninum is an important cause of abortion in dairy cattle. The objective of this observational study was to estimate the rate of vertical transmission of N. caninum in dairy herds in Québec and to investigate horizontal transmission in the same herds. The genealogy of cows from 23 dairy herds were examined. Prevalence of seropositive animals in herds studied varied from 4.3% to 61.8% (average, 21.9%). The overall rate of vertical transmission was estimated to be 44.4%, varying from 0% to 85.7%. Seven cases of horizontal transmission were identified in 6 of the 23 herds studied. Estimated vertical transmission rate varied from herd to herd, but appeared to be higher in herds with a high prevalence of seropositive animals. Although horizontal transmission was identified in 6 herds, it does not appear to be the major route of infection for N. caninum.  相似文献   
130.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
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