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Peter L. M. Msoffe David Bunn A. P. Muhairwa M. M. A. Mtambo H. Mwamhehe A. Msago M. R. S. Mlozi Carol J. Cardona 《Tropical animal health and production》2010,42(2):253-263
A social strategy was tested for implementing Newcastle disease (ND) vaccination and biosecurity improvements among free-ranging chicken at village level in Tanzania. In addition to training the local poultry vaccinators, data recorders and poultry-keepers, the strategy involved training and empowering leaders at the district, ward and village level. The trainings covered poultry health, management, and marketing of village chickens, with an emphasis on ND vaccination and improving biosecurity against avian influenza (AI), The study sites included villages in one ward in each of three each three districts (Iringa, Mtwara-Mikindani, and Mvomero) of mainland Tanzania. Ninety-six local leaders at district level and 101 leaders at ward levels were trained. In addition, 196 farmers (households) were trained, as well as 86 vaccinators and 26 data recorders. Data recorders were also trained as poultry first aid workers. ND vaccination was conducted by the vaccinators, supervised by their local leaders with technical assistance from veterinarians. A total of 158,343 village chickens were vaccinated in three rounds of vaccination three months apart. The training and empowerment of local leaders and local implementers was the key element for success as it fostered the feeling of local ownership of the program and prevented conflicts with other development activities within the villages. We conclude that most animal health programs will increase their odds of success by involving local leaders and by addressing the current challenges facing the farmers. Further assessment on the usefulness of this approach is needed. 相似文献
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Agroforestry (AF) systems have been the focus of numerous research and development projects in southern Africa, yet their
adoption rate generally remains low. Employing on-farm, participatory research techniques in southern Malawi, we compared
the suitability of three AF-based systems that relay crop the dominant staple, maize (Zea mays), with the perennial legumes Sesbania sesban, Tephrosia vogelii, and Cajanus cajan (pigeonpea). Our secondary objective was to compare two methodologies employed to investigate AF adoption: farming systems
based ex ante adoption potential and ex post adoption analysis. Nineteen percent of farmers preferred S. sesban, 26% T. vogelii, and 55% pigeonpea. Between 2001 and 2003, S. sesban adoption ranged from 3 to 6%, T. vogelii from 16 to 20%, and pigeonpea from 76 to 100%. Pigeonpea and T. vogelii were primarily preferred and adopted for their immediate livelihood benefits—a secondary food source in the case of pigeonpea
and a fish poison in the case of T. vogelii. Though S. sesban was the most promising in terms of biophysical impacts, many farmers found it labor intensive and its lack of immediate livelihood
benefits was a deterrent to adoption. With food insecurity a pervasive hardship in the region, farmers will likely continue
to focus on satisfying immediate livelihood needs before prioritizing longer-term soil-quality improvement techniques. Both
ex ante adoption potential and ex post adoption analysis contributed distinct and valuable data, and relying on either exclusively
would have limited our understanding of the AF systems. 相似文献
105.
Techniques for modeling burn probability (BP) combine the stochastic components of fire regimes (ignitions and weather) with
sophisticated fire growth algorithms to produce high-resolution spatial estimates of the relative likelihood of burning. Despite
the numerous investigations of fire patterns from either observed or simulated sources, the specific influence of environmental
factors on BP patterns is not well understood. This study examined the relative effects of ignitions, fuels, and weather on
mean BP and spatial patterns in BP (i.e., BP variability) using highly simplified artificial landscapes and wildfire simulation
methods. Our results showed that a limited set of inputs yielded a wide range of responses in the mean and spatial patterning
of BP. The input factors contributed unequally to mean BP and to BP variability: so-called top-down controls (weather) primarily
influenced mean BP, whereas bottom-up influences (ignitions and fuels) were mainly responsible for the spatial patterns of
BP. However, confounding effects and interactions among factors suggest that fully separating top-down and bottom-up controls
may be impossible. Furthermore, interactions among input variables produced unanticipated but explainable BP patterns, hinting
at complex topological dependencies among the main determinants of fire spread and the resulting BP. The results will improve
our understanding of the spatial ecology of fire regimes and help in the interpretation of patterns of fire likelihood on
real landscapes as part of future wildfire risk assessments. 相似文献
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Joseph P Suman SP Rentfrow G Li S Beach CM 《Journal of agricultural and food chemistry》2012,60(12):3196-3203
The objective of the present study was to differentiate the sarcoplasmic proteome of color-stable (Longissimus lumborum; LL) and color-labile (Psoas major; PM) beef muscles. LL and PM muscles from seven beef carcasses (24 h post-mortem) were fabricated into 2.54 cm steaks, aerobically packaged, and assigned to refrigerated retail display for 9 days. LL steaks demonstrated greater (P < 0.05) color stability and lower (P < 0.05) lipid oxidation than PM steaks. Proteome analyses identified 16 differentially abundant proteins in LL and PM, including antioxidant proteins and chaperones. Proteins demonstrating positive correlation with redness (aldose reductase, creatine kinase, and β-enolase) and color stability (peroxiredoxin-2, peptide methionine sulfoxide reductase, and heat shock protein-27 kDa) were overabundant in LL, whereas the protein overabundant in PM (mitochondrial aconitase) exhibited negative correlation with redness. The color stability of LL could be attributed to the overabundance of antioxidant proteins and chaperones, and this finding suggests the necessity of developing muscle-specific processing strategies to improve beef color. 相似文献
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Chang CH Lee-Fowler TM Declue AE Cohn LA Robinson KL Reinero CR 《Veterinary immunology and immunopathology》2011,144(3-4):437-441
Glucocorticoids (GCs) are palliative for allergic asthma, but allergen-specific immunotherapy (ASIT), which relies on identification of allergens, represents a potentially curative treatment. The purpose of this study was to determine if oral or inhaled GCs would interfere with identification of sensitizing allergens. The hypothesis was that oral but not inhaled GCs would interfere with accurate allergen-specific IgE identification determined by skin and serum testing in experimentally asthmatic cats. Asthma was induced in 18 cats using Bermuda grass allergen (BGA). Cats (n=6/group) were randomized to receive oral GCs (10mg prednisolone q 24 h), inhaled GCs (600 μg budesonide q 24 h) or placebo (q 24 h PO) for one month. Intradermal skin testing (IDST) and serum BGA-specific IgE were measured prior to, during and after treatment. A paired t test was used to compare groups pre- and post-treatment (P<0.05 significant). IDST reactivity was eliminated in 4/6, 3/6, and 1/6 cats receiving oral GCs, inhaled GCs, and placebo respectively. Two weeks after stopping treatment, IDST was again positive in all cats. Serum IgE reactivity to BGA was not significantly diminished by any treatment. In conclusion, a two-week withdrawal from GCs is adequate for IDST, but may not be necessary for serum IgE testing. 相似文献