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1.
In 3 urban areas in Selangor, Peninsular Malaysia between 1973 and 1981, blood from 4080 dogs was examined for haematozoa. The following frequencies were found: Babesia gibsoni 17.7%; microfilariae of Dirofilaria immitis 9.6%; Hepatozoon canis 1.2%; B. canis 1.1%; Ehrlichia canis 0.2%; Trypanosoma evansi 0.1%. A detailed examination of B. gibsoni infections and microfilariasis due to D. immitis with regards to monthly distribution, breed frequency, sex and age, revealed that pedigree and non-pedigree dogs were equally susceptible to Babesia and microfilariae infections.  相似文献   
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Extreme environments are hostile for most organisms, but such habitats represent suitable settings to be inhabited by specialized microorganisms. A marine shallow-water hydrothermal vent field is located offshore in northeast Taiwan, near the shallow shore of the southeast of Kueishantao Island (121°55′ E, 24°50′ N). Research on extremophilic microorganisms makes use of the biotechnological potential associated with such microorganisms and their cellular products. With the notion that extremophiles are capable of surviving in extreme environments, it is assumed that their metabolites are adapted to function optimally under such conditions. As extremophiles, they need specific culture conditions, and only a fraction of species from the original samples are recovered in culture. We used different non-selective and selective media to isolate bacterial species associated with the hydrothermal vent crab Xenograpsus testudinatus and the sediments of its habitat. The highest number of colonies was obtained from Zobell marine agar plates with an overall number of 29 genetically distinct isolates. 16S RNA gene sequencing using the Sanger sequencing method revealed that most of the bacterial species belonged to the phylum Firmicutes and the class Bacilli. The present study indicates that hydrothermal vent bacteria and their secondary metabolites may play an important role for the reconstruction of the evolutionary history of the phylum Procaryota.  相似文献   
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Owing to the growing need for eco-friendly aquaculture, usage of herbal feed supplement receives higher attention. A commercial shrimp feed supplement known as Ban-V is a unique blend of polyherbal extracts that act synergistically with each other to help in improving the immune system, protects hepatopancreas and activates several metabolic pathways for better growth and disease resistance. For that, four supplemental concentrations such as 0.5, 1.0, 2.0 and 3.0 % of Ban-V were used along with commercial shrimp feed, and feed with no supplement (control) were evaluated for 60 days. Results revealed that 2.0% of Ban-V diet fed group showed significantly increased biological performance like (average body weight, average daily growth, feed conversion ratio and survival rate) than control. The tested immunological parameters such as total haemocyte count, oxyhaemocyanin level, phenoloxidase (PO) activity, respiratory burst activity (RB), superoxide dismutase (SOD), lysozyme activity, plasma protein content (PPC) and bactericidal activity were higher in 2.0% test diet fed P. vannamei, when compared to other test and control diet fed shrimp. It is therefore suggested that Ban-V supplementation at a concentration of 2.0% was efficient in stimulating the growth and immunity in shrimp.

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Nano-sized formulations of micronutrient iron (Fe) were found to substantially alter the growth and metabolism of maize plants. Plants fertilized with the optimal recommended dose of Fe in the nano-form (54 μM) registered an enhancement in morphological features, viz. plant height, biomass (shoot and root), and diminution in antioxidant enzyme activities than the plants fertilized with the sub-optimal dose of Fe in the macroform (salts). However, half of the recommended dosage of Fe (27 μM) in the nano-form positively influenced leaf area and proline content of plants too. This indicated that there is a possibility of reducing the dose of Fe supplement for plants in the nano-form to increase the nutrient use efficiency in a major cereal crop like maize. This may open a new era in plant nutrient management with a scope for improvement in nutrient use efficiency using nano-nutrient formulations.  相似文献   
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An extracellular chitinase was purified from Bacillus subtilis. The lethal concentration (LC50) was determined by using chitinase in first, second, and third instars of Spodoptera litura Fab. Chitinase showed the highest insecticidal activity at 6 μM concentration within 48 h. The nutritional indices were also significantly affected by the 6 μM concentration (P < 0.05). Food consumption, efficiency of conversion of ingested and digested food, relative growth rate, and consumption values declined significantly while approximate digestibility was increased. Our study indicates that treatment of host plant leaves with the chitinase can regulate (reduce) larval growth and weight, and enhance the mortality. This may serve as an effective biocide and alternative to Bt toxin.  相似文献   
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 Observations of newer diazotrophs like Acetobacter diazotrophicus and Herbaspirillum spp. in Indian sugarcane varieties is reported here for the first time. A. diazotrophicus was isolated from sugarcane plants where N fertilisation was nil, and numbers in the Indian cultivars were estimated to be up to 106–107 colony forming units g1 fresh weight. N fertilisation was the limiting factor for the isolation of A. diazotrophicus, as evidenced by selective growth patterns in different concentrations of N sources, but Herbaspirillum spp. were found to occur both in N fertilised and unfertilised samples. The fact that N is not the limiting factor for Herbaspirillum spp. was evidenced in a similar study of its growth pattern in different N sources. Received: 14 May 1998  相似文献   
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The gene coding for translationally controlled tumour protein (TCTP) was polymerase chain reaction amplified from haemocyte cDNA of Indian shrimp, Penaeus indicus, and sequenced. The N‐terminal region, a conserved one among all the TCTPs, was shown to have one substitution at position 37, in the Indian isolate. Besides this, there were two substitutions in the C‐terminal region (135, 149), exclusive to the Indian isolate. Phylogenetic analysis suggested a close relatedness of TCTP from P. indicus to Fenneropenaeus chinensis compared with other isolates. Translationally controlled tumour protein gene expression was found to be elevated in the haemocytes of WSSV‐infected shrimps compared with the uninfected ones. However, tissues from the infected shrimps did not exhibit any detectable levels of TCTP expression.  相似文献   
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In swine, even though the pregnant sows were with iron abundance, the inborn iron reserve of piglets was compromised. This indicates the insufficiency of molecular machinery involved in local placental iron flux. Here, we investigated the expression of iron regulatory proteins like hepcidin and ferroportin and also their association with iron reserve, inflammation and oxidative stress in placenta of full-term pregnant sows (n = 6). Amplification and sequencing of placental DNA confirmed the presence of hepcidin (MN579557) and ferroportin (MN565887) sequences and their 100% identity with existing GenBank data. Real-time amplification of placental mRNA revealed significant higher expression of hepcidin (p < .05) than ferroportin. Western blot analysis of placental tissues revealed specific bands for both hepcidin (~8 kDa) and ferroportin (~62 kDa) molecules. Immunohistochemistry revealed the immunoreactivity for both proteins in the cytoplasm and membrane of trophoblastic cells of the placenta. Hepcidin and ferroportin expressions were positively associated with placental non-haem iron reserve (p < .0001; p = .033), lipid peroxidation (p = .0060; p < .0001) and reactive oxygen species level (p = .0092; p = .0292). Hepcidin expression was positively associated with interleukin – 6 (p = .0002) and interferon gamma (p < .0001) expressions but ferroportin expression was negatively associated with interleukin-6 (p = .0005), interleukin-1β (p = .0226) and interferon gamma (p = .0059) expressions. This indicates hepcidin and ferroportin may have a role in controlling the local placental iron flux by acting as a molecular bridge between iron trafficking and inflammation.  相似文献   
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