Effects of increasing dietary protein supplies on milk yield,milk composition,and nitrogen use efficiency in lactating buffalo

Nitrogen efficiency of lactating buffalo can be increased by providing dietary crude protein (CP) precisely to the requirement. Twelve lactating Nili-Ravi buffaloes (6 primiparous and 6 multiparous) at 76?±?37.5 days in milk (DIM) were used in this study. The treatments were diets providing three levels of CP (% DM basis): (1) low-protein?=?11%; (2) medium-protein?=?13.1%; (3) high-protein?=?14.2% according to a 3?×?3 Latin square design. The period length of each treatment was 21 days and the total duration of experiment was 63 days. The diets were designed to provide similar energy. The nitrogen intake of buffalo increased linearly by increasing CP levels. Dry matter intake showed a tendency toward decrease in quadratic fashion, whereas milk yield decreased linearly in high-protein diet. No effect was observed on milk protein yield and content. Increasing the dietary CP levels increased plasma urea nitrogen, whereas glucose and triacylglycerol levels remain unaffected. Efficiency of dietary nitrogen utilization to milk averaged 21% and showed both linear and quadratic decreases by increasing the protein supply levels. In conclusion, low CP level showed higher milk production with low plasma urea nitrogen and high nitrogen efficiency in this experiment.

     

Resistance to foliage feeding aphid in wheat

Experimental trials were conducted at Integrated Pest Management Programme, National Agriculture Research Centre Islamabad, to evaluate the resistance of host plants (cereals) against Rhopalosiphum padi (L.). For evaluation of susceptibility, twenty varieties/-advanced lines of National Uniform Wheat Yield Trails (NUWYT) Normal (N) of year 2004-2005 were used. In seedling bulk tests varieties/advanced lines were grouped into three categories resistant, moderately resistant and susceptible. Data from seedling bulk tests showed that DN-47 and PR 87 lines of wheat were resistant to aphid as compared to the other varieties/-advanced lines. In antixenosis tests varieties/-advanced lines were grouped into three categories, least preferred, moderately preferred, highly preferred. Lines V-01180, DN-47 and PR-84 were least preferred, sixteen varieties/-advanced lines were moderately preferred and only one variety V-9021 was found to be highly preferred.     

瓜棉复合群体对棉花根系的影响

采用整体挖掘冲洗法和图像扫描分析方法,研究瓜棉套作模式下棉花根系在水平0～40 cm、垂直0～80 cm土壤范围内的动态分布及根系特征参数。结果表明,水平方向上,苗期根系主要分布在0～5 cm,蕾期在0～15 cm,花铃期至吐絮期在0～20 cm;垂直方向上,苗期根系主要分布在0～10 cm,蕾期在0～20 cm,花铃期在0～30 cm,吐絮期在0～40 cm。套作棉苗期和蕾期总根长和根表面积小于单作棉,至吐絮期超过单作棉;套作棉苗期和蕾期根总体积小于单作棉;套作棉蕾期和花铃期根系干物质质量小于单作棉。套作棉蕾期、花铃期、吐絮期根系干物质质量与茎粗呈极显著正相关。     

艾丁湖极端嗜碱菌碱性纤维酶的初步研究

从吐鲁番艾丁湖地区６４种土样中筛选到一株能产细胞外嗜碱性纤维素酶的极端嗜碱菌Ａ０４,细胞杆状,革兰氏染色阴性。该菌在ＣＭＣ培养基中产生细胞外纤维素酶,产酶的最适ＰＨ和ＮａＣｌ浓度分别为９．５和０．５％。酶反应最适温度为４０℃,在ＰＨ９．５条件下产生较高的碱性纤维素酶。     

新疆额尔齐斯河大峡谷地衣区系特征的初步研究

根据实地调查并结合已有的文献资料,对新疆额尔齐斯河大峡谷地衣区系进行了初步研究.结果表明:该地区地衣共有72种、1个变种,隶属于6目、16科、30属,其中褐梅属(Melanelia Essl.)、石蕊属(Cladonia Wigg.)、地卷属(Peltigera Willd.)等地衣种类较多,分别占9.33％,10.67％,13.33％.在该地区分布的地衣科目中茶渍目占优势,其科、属、种数分别占该地区地衣总数的68.75％,73.33％,69.33％.根据地衣对环境的适应特征和选择性,将新疆额尔齐斯河大峡谷地衣的地理成分可划分为世界广布成分(20.00％)、环北极成分(26.67％)、温带成分(45.33％)、东亚成分(5.33％)和中国特有种(2.67％)等5个分布类型.其中温带成分和环北极成分占该地区地衣总种数的72.00％,占优势地位.     

Detection of <Emphasis Type="Italic">Mycobacterium avium</Emphasis> subsp. <Emphasis Type="Italic">paratuberculosis</Emphasis> in tissue samples of cattle and buffaloes

Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most of the animals were emaciated. Diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. Intestinal pathology was observed in 29% of buffaloes and 32.8% of cattle. Number of mesenteric lymph node (MLN) showing gross lesions was a bit higher (35.6%) in cattle than buffalo (31.2%). Acid-fast staining of tissue scraping smears revealed the presence of acid-fast bacilli (AFB) in 17.4% intestinal and 16.4% MLN tissue samples in buffalo, while in cattle 19.2% intestinal and 17.8% MLN were found positive for AFB. In buffaloes, PCR confirmed 12.8% intestinal and 12.4% MLN positive samples for M. avium subsp. paratuberculosis. However, in cattle, PCR analysis demonstrated 14.2% positive results for M. avium subsp. paratuberculosis in both MLN and intestinal tissue samples. PCR also confirmed M. bovis in 5.8% of cattle and 5% of buffalo MLN and intestinal tissues. PCR positive tissue samples for M. avium subsp. paratuberculosis were from those animals which were emaciated, having diarrhea, and severe gross lesions. AFB were also detected in tissue scraping smears of these animals. It is concluded that infection by various mycobacterium species can be differentiated by PCR, which is not possible by acid-fast staining technique.     

Characterization of Reactive Red-120 Decolorizing Bacterial Strain Acinetobacter junii FA10 Capable of Simultaneous Removal of Azo Dyes and Hexavalent Chromium

Continual discharge of textile wastewaters loaded with a variety of synthetic dyes and metals is considered as a huge threat to surrounding ecosystems. In order to treat these undesirable pollutants, microbial bioremediation is considered as an efficient and economical technique. This study was conducted to evaluate the use of bacterial strains for simultaneous removal of azo dyes and hexavalent chromium [Cr(VI)]. Fifty-eight bacterial strains were isolated from Paharang drain wastewater and tested for their potential to decolorize reactive red-120 (RR-120) in the presence of 25 mg L^?1 of Cr(VI). Among the tested isolates, FA10 decolorized the RR-120 most efficiently and was identified as Acinetobacter junii strain FA10. Based on quadratic polynomial equation and response surfaces given by the response surface methodology (RSM), Cr concentration and pH were found to be the main factors governing the RR-120 decolorization by FA10. The strain FA10 also exhibited a substantial salt resistance since it showed a considerable decolorization of RR-120 even in the presence of 150 g L^?1 of NaCl. Moreover, the strain FA10 also showed the potential to simultaneously remove the Cr(VI) and the selected azo dyes in the same medium. More than 80 % of the initially added Cr(VI) was removed over 72 h of incubation along with the appreciable decolorization efficiency. The strain FA10 also exhibited good tolerance to considerable levels of different heavy metals. The findings of this study suggest that the strain FA10 might serve as an efficient bioresource to develop the biotechnological approaches for simultaneous removal of different azo dyes and heavy metals including Cr(VI).     

Extraction of Heavy Metals from Manure and their Bioavailability to Spinach (Spinacia Oleracea L.) after Composting

An investigation was carried out on the extractability of heavy metals (HM) from livestock manure during composting and their uptake by spinach (Spinacia oleracea L.) from compost-amended soil. Significant temporal changes were recorded for elements during composting of manure. Higher concentrations of metals were observed during the early stages of composting. Conversely, later stages of composting produced higher amounts of calcium (Ca), magnesium (Mg) and sodium (Na) in the water extract. Total carbon (C) in the samples was inversely related to the length of composting. The application of composted manure increased spinach growth as compared to the fresh manure. Concentrations of HM in spinach varied in the order iron (Fe) > zinc (Zn) > manganese (Mn) > cadmium (Cd) > lead (Pb) > copper (Cu) and their release from post-harvest soil was identical to that in manure samples. The low extractability of HM may suggest that the use of composted manures would lessen environmental pollution problem in the fields.     

Prediction of Contaminants Migration at Unlined Landfill Sites in an Arid Climate – a Case Study

Landfilling of municipal solid waste (MSW) is associated with the generation of leachate that is highly contaminated. Contaminant migration from disposal areas to groundwater poses a threat to the environment and the human health. This study examined the contaminant migration at a landfill site in Kuwait. The migration characteristics of contaminants were analyzed using advanced computing systems to predict the long-term plume concentration in underlying soils and aquifers located directly below the final waste layer. Mathematical models of contaminant migration were applied to existing landfill sites using MIGRATEv9 computer program to illustrate the scope and extent of soil and water contamination. Two main cases were modeled as follows: (1) water table is deep below landfill and (2) water table is rising into the landfill. The models included advective-dispersion, and buried landfills systems. The comparison between models results suggested that vertical Darcy velocity had a significant impact on migration behavior of contaminants. The concentration was increased by 24.5% by increasing the vertical Darcy velocity from 0.005 to 0.009 m/year. Advection–dispersion models and water rising models with fixed top boundary and aquifer bottom boundary at 2 and 3.5 m showed almost the same migration behavior. In addition, models of buried landfill system where water table was 5 m from ground surface produced a maximum contaminant concentration of 17 630 mg/L after 25 years at 5 m depth.