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41.
The Cracidae family of neotropical birds is regarded as one of the most severely threatened in the world. They traditionally have been extensively hunted, and, thus, ex situ efforts for their conservation are recommended and involve the optimization of their care in captivity. Nutrition is a fundamental aspect of husbandry, which influences survival and reproduction in captivity. In this study, a total of 29 animals, including 3 species (Penelope obscura, Penelope superciliaris, and Aburria jacutinga), were subjected to monthly physical examination and blood sampling before and after dietary conversion from the traditional diet of broiler feed, fruits, and vegetables to a nutritionally balanced commercial diet specifically designed for wild Galliformes. The diet change produced differences in several parameters tested, including an increase (P < 0.05) in hemoglobin concentration for all species. Increases (P < 0.05) in erythrocyte count, packed cell volume, and body weight were observed in P. obscura, with a concomitant decrease in the standard deviation for such parameters that show improved uniformity. Globulins and lipase also were reduced (P < 0.05) in P. obscura. Although leukocyte count was lowered and eosinophils were increased in all 3 species after dietary conversion, only these 2 changes were significant (P < 0.05) in P. superciliaris. A. jacutinga had higher (P < 0.05) blood glucose concentrations than the other species, but diet had no effect on this parameter. Blood uric acid concentrations were higher (P < 0.05) after conversion to the commercial diet in P superciliaris. The provision of a commercial extruded diet as a single food source was beneficial, which led to a general improvement in clinical aspects and group uniformity in these 3 species of Cracidae.  相似文献   
42.
The prevalence of Chlamydophila psittaci (formerly Chlamydia psittaci) infection was assessed in 95 apparently healthy, captive Amazon parrots from three breeder collections in southeastern and west-central Brazil. Cloacal swabs from 95 birds were tested for chlamydial antigen, which was detected by direct immunofluorescence (DIF), and serum samples from 44 of these birds were tested for antibodies to C. psittaci using an enzyme-linked immunosorbent assay. The prevalences of active infection as detected by DIF were 16.7%, 22.2%, and 56.1%, and seroprevalences were 100%, 87.5%, and 60% in flocks A, B, and C, respectively. We can therefore infer that C. psittaci may be widespread in captive parrot populations in Brazil.  相似文献   
43.
Veterinary Research Communications - An outbreak of sheeppox was investigated in a cluster of villages situated in Western Himalayan ranges of a Northern Indian state. Non-migratory sheep...  相似文献   
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45.
To date, no hormonal treatments are available for control of shrimp reproduction and only eyestalk ablation is of practical use. The crustacean hyperglycemic hormone (CHH) is the most abundant neuropeptide of the eyestalk CHH family. It plays an important role in the regulation of hemolymph glucose levels, as its principal function, but it is also implicated in additional physiological processes such as moulting and reproduction. In the present study, the cDNA encoding Litopenaeus schmitti (Burkenroad) mature CHH was cloned into the Escherichia coli pTYB2 expression vector. Using this strategy we have obtained, for the first time, the recombinant CHH from L. schmitti with its C‐terminus fused to an intein tag. The expected fused protein of about 63 KDa was expressed in E. coli forming inclusion bodies. It was purified in a soluble form by electroelution following molecular size fractionation in sodium dodecil sulphate polyacrylamide gel electrophoresis. The ability of the chimeric CHH protein to elevate glucose levels in the hemolymph of the eyestalk‐ablated Litopenaeus vannamei (Boone) shrimps indicates that its biological activity as hyperglycemic protein is preserved. The results provide an alternative tool to obtain soluble recombinant proteins from the CHH family of neuropeptides to get a better understanding of shrimp endocrinology.  相似文献   
46.
The objective of this study was to isolate and identify yeast strains from broilers excreta and to evaluate in vitro their potential for probiotic use in animal production.Methods and resultsNine yeast strains were isolated and presumptively pre-identified by biochemical assays. These isolates were grouped in six different molecular profiles using PCR-fingerprinting technique. Each profile was identified by sequencing of the D1/D2 domains of the large subunit of the 26S rRNA gene. These yeasts were identified as: Trichosporon sp. (LV-2), Wickerhamomyces anomalus (LV-6), Pichia kudriavzevii (LV-8), Kodamaea ohmeri (LV-9) and Trichosporon asahii (LV-10). A pre-screening of the strains for probiotic use was based on their ability to agglutinate pathogenic micro-organisms. These yeast strains were characterized for specific growth rate, duplication time, their cell surface hydrophobicity, medium acidification, resistance to low pH (2.0, 2.5 and 3.0) and concentrations of bile salts (0.3% and 0.6%). The isolate of W. anomalus (LV-6) had the highest agglutinating and adherence capacity, a growth rate of 2.07 × 108 cfu/mL in 24 h at 30 °C, decreasing the medium pH from 6.5 to 5.23, a 25% hydrophobicity and an elevated capacity to grow under stress conditions.ConclusionsW. anomalus strain LV-6 showed the best characteristics for use as a probiotic candidate.Significance and impact of the Study:The data from this study helped in choosing a probiotic candidate from yeast to use in broiler production.  相似文献   
47.
The global distribution of citrus black spot (CBS) disease, caused by Phyllosticta citricarpa, is climatically constrained, which is evident from its occurrence in citrus growing areas with warm, summer rainfall and its absence from areas with cooler, Mediterranean-type winter rainfall. Various epidemiological and modelling studies have supported this observation, predominantly estimating unsuitability for P. citricarpa in Mediterranean type climates, with no more than marginal suitability estimated at a few localities within some regions with Mediterranean type climates. The study by Martínez-Minaya et al. (European Journal of Plant Pathology, 143, 69–83, 2015), describes an historic sequence of recorded CBS occurrence in parts of South Africa, conducts an autocorrelation analysis and a correlative analysis with Köppen-Geiger climate zones and makes observations about the occurrence of certain Köppen-Geiger climate zones in the European Union. The study suggests that significant portions of the European Union and the broader Mediterranean basin are climatically similar to warm, summer rainfall areas in South Africa where P. citricarpa persists and causes CBS disease and concludes that the potential distribution of P. citricarpa is less constrained by climatic factors than spatial contagion. However, in this critique we expose methodological shortcomings in the Martínez-Minaya et al. (European Journal of Plant Pathology, 143, 69–83, 2015) study and conclude that the study grossly overestimated the extent of the geographical area that could support P. citricarpa, thereby rendering the findings scientifically unreliable.  相似文献   
48.
This paper proposes two interrelated arguments: first, it is argued that agro-commodity traders are uniquely placed at the crossroads of agricultural trade to benefit from agricultural commodity speculation; and second, that the networks constituting their operations are central to their hedging activities. The case of Cargill—the largest privately owned company in the United States and one of the largest agricultural traders in the world—is used to support this argument by unpacking its operations, structure, and hedging strategies. In order to connect the operations of Cargill to its speculating strategies, this paper first traces how agriculture and finance have become increasingly intertwined leading to heightened agricultural commodity speculation. Second, Cargill will be positioned within this process by analyzing how it has financialized its own strategies and its Corporate Platform. Third, Black River Asset Management, Cargill’s private equity arm, will be analyzed to show how it uses the information moving through Cargill’s Platform to engage in hedging and/or speculation.  相似文献   
49.
This study was carried out to investigate fifteen cases of acute lethal infection of calves (≤ 4 months of age) by the protozoan parasite Theileria (T.) annulata in the south of Portugal. Calves developed multifocal to coalescent nodular skin lesions, similar to multicentric malignant lymphoma. Infestation with ticks (genus Hyalomma) was intense. Theileria was seen in blood and lymph node smears, and T. annulata infection was confirmed by isolation of schizont-transformed cells and sequencing of hypervariable region 4 of the 18S rRNA gene. At necropsy, hemorrhagic nodules or nodules with a hemorrhagic halo were seen, particularly in the skin, subcutaneous tissue, skeletal and cardiac muscles, pharynx, trachea and intestinal serosa. Histologically, nodules were formed by large, round, lymphoblastoid neoplastic-like cells. Immunohistochemistry (IHC) identified these cells as mostly CD3 positive T lymphocytes and MAC387 positive macrophages. A marker for B lymphocytes (CD79αcy) labeled very few cells. T. annulata infected cells in these nodules were also identified by IHC through the use of two monoclonal antibodies (1C7 and 1C12) which are diagnostic for the parasite. It was concluded that the pathological changes observed in the different organs and tissues were caused by proliferation of schizont-infected macrophages, which subsequently stimulate a severe uncontrolled proliferation of uninfected T lymphocytes.  相似文献   
50.
Meat and bone meal (MBM) utilization for animal production was banned in the European Union since 2000 as a consequence of the appearance of transmissive spongiform encephalopathies. Soil application could represent a lawful and effective strategy for the sustainable recycling of MBM due to its relevant content of nutritive elements and organic matter. The effectiveness of MBM as organic fertilizer needs to be thoroughly investigated since there is a lack of knowledge about the mineralization dynamics of MBM in soil and the impact of such residues, in particular the high content of lipids, on soil biochemical and microbiological properties. For this aim, a defatted (D) and the correspondent non-defatted (ND) MBM were added at two rates (200 and 400 kg N ha?1) to two different moist soils and incubated at 15 and 20 °C for 14 d. MBM mineralization dynamics was studied by measuring CO2 evolution. Water extractable organic C, K2SO4-extractable NO3? and NH4+, microbial biomass ninhydrin-reactive N, enzymatic activities (FDA, urease, protease, alkaline phosphatase) and microbial composition (aerobic and anaerobic bacteria, fungi) were measured 2 and 14 d after MBM addition to the soil. The rate of CO2 evolution showed a maximum 2–3 d after the addition of MBM, followed by a decrease approaching the control. MBM mineralization was fast with, on average, 54% of total CO2 evolved in the first 4 d of incubation at 20 °C. The percentage of added C which was evolved as CO2 at the end of the incubation period ranged between 8% and 16% and was affected by temperature, soil type and MBM treatment (ND > D). Soil amendment with MBM caused a noteworthy increase in both extractable NH4+ and NO3? (about 50% of added N) which was higher for ND. The addition of MBM also enhanced microbial content and activity. Microbial biomass increased as a function of the rate of application and was higher for ND with respect to D. The increase in numbers of aerobic and anaerobic bacteria and fungi caused by MBM addition was, in general, more pronounced with ND. Enzymatic activity in amended soils showed an enhancement in nutrient availability and element cycling. At the rate of application of present work, lipids did not cause adverse effects on soil microorganisms.The potential of MBM as effective organic fertilizer was supported by the large increase in available N and the enhancement of the size and activity of soil microorganisms.  相似文献   
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