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81.
Journal of Soils and Sediments - Compression studies can provide insights into evaluating the engineering potential and environmental impact of clay. The objective of this study was to...  相似文献   
82.
Zargham Khan, M., Muhammad, G., Umar, A. and Ali Khan, S., 1997. A preliminary comparison of plasma fibrinogen concentrations, leukocyte numbers and erythrocyte sedimentation rate as non-specific indicators of inflammatory conditions in buffalo (Bubalis bubalis). Veterinary Research Communications, 21 (4), 265-271The plasma fibrinogen concentration (Fib), total leukocyte count (TLC), neutrophil, lymphocyte and monocyte numbers, and the erythrocyte sedimentation rate (ESR) were determined in 153 buffaloes suffering from different clinical conditions. Fib increased significantly (p < 0.05) in chronic mastitis, pyrexia, pyometra, cutaneous abscesses, tail gangrene and acute indigestion, whereas in most of the other conditions studied it varied non-significantly. TLC increased significantly in chronic mastitis, pyrexia, endometritis, cutaneous abscesses and infected skin wounds. An increase in neutrophils was associated with an increased TLC. Numbers of lymphocytes varied non-significantly in most of the conditions. Monocytes decreased significantly in most of the acute conditions. ESR was significantly elevated in all clinical conditions. Significantly increased mean Fib values in the different conditions varied from 703 ± 119 to 725 ± 140 mg/dl, while the maximum individual value was 1510 mg/dl in a case of cutaneous myiasis. The significantly increased mean TLC ranged from 9.48 ± 2.91 to 11.1 ± 3.5 × 103/µl, while it was 21.7 × 103/µl in a case of meningitis. ESR values in sick buffaloes varied from 57 to 111 mm in the first hour.  相似文献   
83.
对50头泌乳中期的奶牛进行为期6周的饲养试验,研究高粗料高脂肪日粮对奶牛血液代谢产物、瘤胃发酵和干物质消化率的影响。试验设有10个重复,每个重复5头奶牛,每头奶牛给定一种日粮。试验用日粮为:对照日粮(日粮1)和试验日粮(高粗料75%高脂肪7.5%,日粮2;高粗料,中等水平脂肪5.0%,日粮3;中等水平粗料65%,高水平脂肪,日粮4;中等水平粗料和脂肪,日粮5;或者对照日粮中含有50%粗料和2.0%脂肪)。这些日粮含氮量相同(CP17.7%)。粗饲料由20苜蓿干草、40%苜蓿半干青贮和40%青贮玉米组成。所用脂肪由80%瘤胃 保护脂肪和20%黄色油脂组成。试验结果表明:试验组和对照组的血糖浓度差异不显著;试验组的血浆非酯化脂肪酸(NEFA)高于对照组。而奶牛采食日粮的粗饲料和脂肪水平不同,其NEFA差异不显著;对照组、试验组与粗饲料和脂肪水平不同的日粮的瘤胃PH、瘤胃VFA浓度和干物质消化率差异不显著。  相似文献   
84.
Twenty-two buffalo bulls suffering from three different types of infertility were slaughtered and used for this study. Except for the reproductive system, no signs of localised or generalised disease were observed. Microbiological investigations were negative for brucellosis, vibriosis, mycoplasma and other non-specific microorganisms. Nine bulls with type 1 infertility had low bodyweights and underdevelopment of testes, accessory sex glands and endocrine glands. This picture suggests a total dysfunction of the pituitary-growth-gonadal axis. One bull of this type also showed bilateral epididymitis. Four out of 11 bulls with type 2 infertility had low bodyweights and most suffered from underdevelopment of testes, accessory sex glands and endocrine glands. Six bulls of this type had lesions of either epididymitis or orchitis or both. Two of these animals showed adhesions of periorchitis. One also showed seminal vesiculitis. In two bulls with type 3 infertility, bodyweights, reproductive organs and endocrine glands were normal. In later life, they yielded poor quality semen. Semen samples collected a few months before slaughter from nine bulls with type 2 and type 3 infertility were of poor quality and had higher percentages of abnormal spermatozoa in most cases.  相似文献   
85.
This study was conducted to evaluate the sexual performance of 10-month-old, ram lambs of different breed groups. Eight ram lambs each of Awassi (A), F1 Charollais × Awassi (CA) and F1 Romanov × Awassi (RA) breed types were subjected to sexual performance tests by being individually exposed to two oestrous Awassi ewe lambs for four 20-min periods. Bouts of leg kicking and anogenital sniffing were similar among breed groups. Mounting frequency was greater (p < 0.05) in RA than in A and CA ram lambs. Tail-raising was greater (p < 0.05) and mating rate tended to be greater (p < 0.10) in A than in RA and CA ram lambs. The number of mounts per tail-raising (efficiency) was influenced by breed group and test day (p < 0.05). Awassi ram lambs maintained the best efficiency throughout the experiment. Efficiency in RA and CA ram lambs improved with each test day. Results of the present study indicate that RA ram lambs have greater mounting frequency than A and CA, while Awassi are more capable of mating with fat-tailed females than the CA and RA ram lambs.  相似文献   
86.
The increasing concentration of cadmium (Cd) in agricultural soil has resulted in crop productivity loss. The activation of the antioxidative enzyme system and its synergy with sulphur assimilation may be required as one of the mechanisms for the alleviation of the effects of Cd. In the present study the activities of antioxidative enzymes and sulphur assimilation were studied in Cd‐treated wheat (Triticum aestivum) cultivars to assess their involvement in determining yield potential. The cultivar WH542 (low yielding type) accumulated Cd to a greater amount in both root and leaf, and also exhibited higher contents of H2O2 and thiobarbituric acid reactive substance and the activity of superoxide dismutase (EC 1.15.1.1) than cultivar PBW343 (high yielding type). The activities of other antioxidative enzymes, catalase (EC 1.11.1.6), ascorbate peroxidase (EC 1.11.1.11), glutathione reductase (EC 1.6.4.2) and glutathione peroxidase (EC 1.11.1.9), activity of ATP‐sulfurylase (EC 2.7.7.4), sulphur content, photosynthetic, growth and yield characteristics were higher in PBW343 than in WH542 in Cd treatment compared to the control. The results suggest that the efficient functioning of enzymes of the antioxidative system and sulphur assimilation helped in alleviating the effects of Cd in PBW343, protected photosynthetic ability and maintained high yielding potential of the cultivar.  相似文献   
87.
Pollen embryos were obtained from eight genotypes and viable green plants were regenerated from four genotypes in an anther-culture experiment with 165 genotypes of Phleum pratense L. Formation of proembryos inside the cultured anthers during the first 10—12 days was significantly influenced by genotypes and by the type of nutrient media. Primary embryos developed into multiple secondary embryos before regeneration of plants. Among a total of 62 plants regenerated, only 13 were albinos. Of the green regenerants, 11 were triploid while 35 were hexaploid when DNA-content was measured by flow cytometry. Eight plants with a triploid DNA-content did possess the triploid chromosome number of 21. Triploid and hexaploid regenerants from two different parents showed simplified isozyme (GPI and PGD) banding patterns relative to that of their parents.  相似文献   
88.
Screening sorghum genotypes for salinity tolerant biomass production   总被引:1,自引:0,他引:1  
Genetic improvement of salt tolerance is of high importance due to the extent and the constant increase in salt affected areas. Sorghum [Sorghum bicolor (L.) Moench] has been considered relatively more salt tolerant than maize and has the potential as a grain and fodder crop for salt affected areas. One hundred sorghum genotypes were screened for salinity tolerance in pots containing Alfisol and initially irrigated with a 250-mM NaCl solution in a randomized block design with three replications. Subsequently 46 selected genotypes were assessed in a second trial to confirm their responses to salinity. Substantial variation in shoot biomass ratio was identified among the genotypes. The performance of genotypes was consistent across experiments. Seven salinity tolerant and ten salinity sensitive genotypes are reported. Relative shoot lengths of seedlings were genetically correlated to the shoot biomass ratios at all stages of sampling though the relationships were not close enough to use the trait as a selection criterion. In general, the whole-plant tolerance to salinity resulted in reduced shoot Na+ concentration. The K+/Na+ and Ca2+/Na+ ratios were also positively related to tolerance but with a lesser r 2. Therefore, it is concluded that genotypic diversity exists for salt tolerance biomass production and that Na+ exclusion from the shoot may be a major mechanism involved in that tolerance.  相似文献   
89.
Summary The adaptability and productivity of cool-season food legumes (chickpea, faba bean, lentil, pea) are limited by major abiotic stresses including drought, heat, frost, chilling, waterlogging, salinity and mineral toxicities. The severity of these stresses is unpredictable in field experiments, so field trials are increasingly supplemented with controlled-environment testing and physiological screening. For drought testing, irrigation is used in dry fields and rain-out shelters in damp ones. Carbon isotope discrimination (Δ13C) is a well-established screen for drought tolerance in C3 cereal crops which is now being validated for use in grain legumes, but it is relatively expensive per sample and more economical methods include stomatal conductance and canopy temperature. Chickpea lines ICC4958 and FLIP87-59C and faba bean line ILB938 have demonstrated good drought tolerance parameters in different experiments. For frost tolerance, an efficient controlled-environment procedure involves exposing hardened pot-grown plants to sub-zero temperatures. Faba beans Cote d’Or and BPL4628 as well as lentil ILL5865 have demonstrated good freezing tolerance in such tests. Chilling-tolerance tests are more commonly conducted in the field and lentil line ILL1878 as well as derivatives of interspecific crosses between chickpea and its wild relatives have repeatedly shown good results. The timing of chilling is particularly important as temperatures which are not lethal to the plant can greatly disrupt fertilization of flowers. Salinity response can be determined using hydroponic methods with a sand or gravel substrate and rapid, efficient scoring is based on leaf symptoms. Many lines of chickpea, faba bean and lentil have shown good salinity tolerance in a single article but none has become a benchmark. Waterlogging tolerance can be evaluated using paired hydroponic systems, one oxygenated and the other de-oxygenated. The development of lysigenous cavities or aerenchyma in roots, common in warm-season legumes, is reported in pea and lentil but is not well established in chickpea or faba bean. Many stresses are associated with oxidative damage leading to changes in chlorophyll fluorescence, membrane stability and peroxidase levels. An additional factor relevant to the legumes is the response of the symbiotic nitrogen-fixing bacteria to the stress.  相似文献   
90.
Summary Studies on genetic diversity in chickpea (Cicer arietinum L.) indicated the existence of considerable amount of variation for grain yield and its components in the material. One hundred and thirty two genotypes fell into eight clusters. The covariation structure studied by means of factor analysis indicated the possibility of obtaining, through hybridization, genotypes physiologically and morphologically more efficient. Multivariate analysis of data from 7 parents and 21 F1 hybrids indicated weak correspondence between D2-analysis and canonical variate analysis. As there was no relationship between heterosis over midparent and genetic distance between the parents, so the traditional approach of making a large number of crosses is being suggested.  相似文献   
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