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1.
A mixture neural methodology for computing rice consumptive water requirements in Fada N’Gourma Region, Eastern Burkina Faso 总被引:1,自引:1,他引:1
Seydou Traore Yu-Min Wang Chun-E. Kan Tienfuan Kerh Jan Mou Leu 《Paddy and Water Environment》2010,8(2):165-173
Crop consumptive water requirement (Crop-ET) is a key variable for developing management plans to optimize the efficiency
of water use for crop production particularly in semiarid zone. In Burkina Faso, the unfavorable climatic conditions characterized
by the low and unevenly distribution of rainfall have pushed water resources management to the forefront of the crop production
issue. Crop-ET is extremely required in rainwater effective management for mitigating the impact of water deficit on the crops.
Basically, Crop-ET determination involves reference evapotranspiration (ETo) and crop coefficient (Kc) which required complete
climatic data and specific site crop information, respectively. ETo estimation with the recommended FAO56 Penman–Monteith
(PM) equation is limited in Burkina Faso due to the numerous meteorological data required which are not always available in
many production sites. In such circumstances, research to compute directly Crop-ET as an alternative to the two-step approach
of calculating ETo and determining site specific Kc, seems desirable. Therefore, this study aims to evaluate the performance
of a mixture principal component analysis neural network (PCANN) model for computing rice Crop-ET directly from temperatures
data in Fada N’Gourma region located in Eastern Burkina Faso, Africa. From the statistical results, rice Crop-ET can be successfully
computed by using PCANN methodology, when only temperatures data are available in this African semiarid environment. Thus,
in poor data situation, Crop-ET direct computation can be rapidly addressed through PCANN model for agricultural water management
in African semiarid regions. 相似文献
2.
Fatou Ndoye Aboubacry Kane Niokhor Bakhoum Arsène Sanon Dioumacor Fall Diégane Diouf Samba Ndao Sylla Amadou Mustapha Bâ Mame Ourèye Sy Kandioura Noba 《Agroforestry Systems》2013,87(4):941-952
The benefits of inoculation with six arbuscular mycorrhizal fungi (AMF) isolates (Glomus aggregatum, G. fasciculatum, G. intraradices, G. manihotis, G. mosseae, and G. verriculosum) were investigated on seedlings of Acacia senegal (L.) Willd., a multipurpose tree legume highly valued for arabic gum production. Mycorrhizal root colonization, plant growth and relative mycorrhizal dependency (RMD) were measured in A. senegal seedlings growing in soils from three geographical sites in Senegal (Dahra, Bambey and Goudiry) and two soil conditions (sterilized vs unsterilized) in the glasshouse. The impact of inoculation on mycorrhizal root colonization and plant growth depended on AMF isolates, soil origins and soil conditions. Mycorrhizal root colonization and plant growth were increased in sterilized soils regardless of soil origin and AMF isolates. The degree of RMD of A. senegal seedlings varied with soil origin, soil condition and AMF isolates. A. senegal showed the highest RMD values, reaching a maximum of 45 %, when inoculated with G. manihotis. However, in unsterilized soils, no significant effect of AMF inoculation on plant growth was observed despite significant root colonization with certain AMF isolates in Dahra and Goudiry soils. This indicates that the most infective AMF isolates were not the most effective and unsterilized soils may contain effective mycorrhizal propagules. In conclusion, it is important to consider the native mycorrhizal component of the soils before harnessing mycorrhizal inoculation programs for sustainable agroforestry systems. 相似文献
3.
In this study, by using the polymerase chain reaction (PCR) diagnosis for the detection and identification of Mycoplasma, we investigated mycoplasmas contaminating the semen of yearling bulls affected by seminal vesiculitis. The bulls presented neither subclinical nor clinical contagious bovine pleuropneumonia signs and the complement fixation test for specific antibodies was negative. Furthermore, we have investigated mycoplasmas isolated from semen of healthy breeding bulls of several breeds and origins, which routinely underwent breeding soundness examinations and presented no clinical signs of seminal vesiculitis. We were able to demonstrate mycoplasma infection in all tested samples by i) growth on mycoplasma-specific media and ii) a PCR-based method using a mycoplasma-specific MGSO/GPO1 primer set to amplify the 16S fragment rDNA. In addition, the identification of Mycoplasma species was made by PCR using the MSC1/MSC2 primer set that specifically amplifies M. mycoides subsp. mycoides SC or the MM450/MM451 primer set followed by AsnI digestion analysis in order to identify M. mycoides subsp. mycoides LC. The data presented herein clearly show that M. mycoides subsp. mycoides SC infection was associated with seminal vesiculitis while M. mycoides subsp. mycoides LC was only found in bull semen from healthy control animals. Our findings confirm that the M. mycoides subsp. mycoides SC is shed in the sperm making the ejaculate a valuable biological sample for the isolation of these bacteria from serologically negative animals. Although the pathogenic role of M. bovigenitalium in bull seminal vesiculitis has been established, our clinical findings, semen characteristics, microbiological and bacterial genomic analysis strongly suggest that M. mycoides subsp. mycoides SC may contribute to induce vesicular adenitis in the bull. 相似文献
4.
Artificial neural network for modeling reference evapotranspiration complex process in Sudano-Sahelian zone 总被引:5,自引:0,他引:5
The major problem when dealing with modeling evapotranspiration process is its nonlinear dynamic high complexity. Researchers developed reference evapotranspiration (ET-ref) estimation models in rich and poor data situations. Thus, the well-known Penman-Monteith (PM) model always performs the highest accuracy results of ET-ref from a rich data situation. Its application in many areas particularly in developing countries such as Burkina Faso has been limited by the unavailability of the enormous climatic data required. In such circumstances, simple empirical Hargreaves (HARG) equation is often used despite of its non-universal suitability. The present study assesses the artificial neural network (ANN) performance in ET-ref modeling based on temperature data in Bobo-Dioulasso region, located in the Sudano-Sahelian zone of Burkina Faso. The models of feed forward backpropagation neural network (BPNN) algorithm type ANN and Hargreaves (HARG) were employed to study their performance by comparing with the true PM. From the statistical results, BPNN temperature-based models perform better than HARG. Beside, when wind speed is introduced into the neural network models, the coefficient of determination (r2) increases significantly up to 9.52%. While, sunshine duration and relative humidity might cause only 3.51 and 6.69% of difference, respectively. Wind is found to be the most effective variable extremely required for modeling with high accuracy the nonlinear complex process of ET-ref in the Sudano-Sahelian zone of Burkina Faso. 相似文献
5.
Aimé Sévérin Kima Wen Guey Chung Yu-Min Wang Seydou Traoré 《Paddy and Water Environment》2015,13(4):379-389
The uncertainty of monsoon rainfall and the decreasing availability of irrigation water, as a result of climate change, and high water demand of other sectors have resulted to wide adoption of alternate wetting and drying (AWD) technique especially in irrigated lowland rice production to overcome water scarcity. However, under climate change circumstances, AWD can be optimized when taking advantage of favorable water seasonality conditions to increase crop yield and irrigation water use efficiency. Therefore, a field trial was conducted to find suitable water depth for reducing rice irrigation water use by combining four different water depth treatments (T2cm, T3cm, T4cm, and T5cm) with rainfall through a randomized complete block design having 3 replications. Water depths were applied weekly from transplanting to heading. The results showed that water stress at vegetative stage decreased plant height and tillers number between 7 and 33 % at panicle initiation, followed by total and partial growth recovery. In addition, panicle number per hill showed a 53–180 % decrease at the heading stage. Severe water stress induced by the lowest water treatment significantly reduced yield components between 15 and 52 % at harvest. It was found that weekly application of 3 cm water depth combined with rainfall improved AWD effectiveness, and yielded the highest beneficial water productivity with less yield expenses. 相似文献
6.
The growth and reproduction of Eudrilus eugeniae were evaluated in four animal species wastes under laboratory conditions. Two hatchlings were introduced in 100 g of each animal waste i.e. cow, sheep, pig, and chicken after 15 days of pre-composting. Biomass gain, mortality, sexual maturity, and cocoons production were monitored periodically for 21 weeks. No mortality was observed in any waste. The maximum weight gain per worm and the highest growth rate per worm per week were obtained in chicken waste. Net biomass gain per worm were 1.01 ± 0.52 g, 1.318 ± 0.07 g, 0.87 ± 0.1 g, and 1.69 ± 0.15 g respectively for cow, sheep, pig, and chicken wastes. The highest number of cocoons produced per worm per day was obtained in chicken waste followed in decreasing order by sheep, cow, and pig waste. The mean number of cocoons produced per worm per day in chicken waste was 40.87% greater than these produced per day in pig waste.Among the four animal species, chicken, sheep, and cow were the most favourable wastes for the growth and reproduction of E. eugeniae, and hence can be recommended as feed materials in large scale vermicomposting facilities. 相似文献
7.
Giorgia della Rocca Juliana Tabarelli Brondani Flávia Augusta de Oliveira Martina Crociati Lakamy Sylla Agnes Elad Ngonput Alessandra Di Salvo Stelio Pacca Loureiro Luna 《Veterinary anaesthesia and analgesia》2017,44(5):1253-1261
Objective
The aim of this study was to validate the Italian version of the UNESP–Botucatu Unidimensional Composite Pain Scale (UCPS-IV) for assessing postoperative pain in cattle.Study design
Video analysis and psychometric testing.Animals
A total of 40 Nellore cattle, age 2–3 years, weighing 365 ± 51 kg.Methods
An English version of the scale was translated to Italian and back translated to English to ensure semantic equivalence. A total of four Italian observers and the researcher who developed the original scale (considered as the gold standard) analysed videos of 40 cattle previously subjected to orchiectomy (recorded for each cattle at four predetermined timepoints during the perioperative period) unaware of the videos’ timepoint. They assigned a pain score [ranging from no pain (0) to severe pain (10)] using the Italian version of the scale and verified the need for analgesic treatment for each animal. The obtained scores were subjected to psychometric validity, responsiveness and reliability tests.Results
The factor analysis of the scale resulted in a one-factor solution. Significant changes in pain scores in response to surgery and analgesics confirmed not only the content and construct validity, but also responsiveness. The agreement between the researcher who developed the original scale and the blinded observers and the correlation between the pain scores determined by the scale and those determined by three classical unidimensional pain scales confirmed criterion and concurrent validity. Internal consistency of the scale was excellent. Inter- and intrarater reliability ranged from moderate to good and from moderate to very good for all scale items, respectively, supporting reproducibility and stability. The cut-off point for rescue analgesia calculated by the receiver operating characteristic curve was > 3.Conclusions and clinical relevance
The results confirm that the UNESP–Botucatu UCPS-IV appears to be a valid and reliable tool for the assessment of postorchiectomy pain in the bovine species. The determination of a cut-off point for rescue analgesia is also helpful for guiding analgesic therapy. 相似文献8.
9.
Seydou Sylla Youssouf Sidimé Yixue Sun Sayon Doumbouya Yanlong Cong 《Tropical animal health and production》2014,46(7):1185-1191
Brucellosis is one of the world’s major zoonotic diseases associated with reproductive disorders and a potential infection of human. Brucellosis leads to serious economic losses due to late-term abortion, stillbirth, weak calves, and sterility. In Guinea, the data on brucellosis was only detected as far back as 10 years ago. The purpose of this study was to estimate the prevalence of bovine brucellosis in the provinces of Macenta and Yomou of Guinea. A structured questionnaire was used in the clinical study, and 345 cattle were clinically examined. Three hundred serum samples were initially subjected to the Rose Bengal test (RBT); the positive results of which were confirmed by the complement fixation test (CFT). The investigation indicated that farmers had little information on brucellosis. Hygroma, abortion, sterility, and placental retention were the observed symptoms. Of the 29 RBT-positive samples, 26 were confirmed by CFT. The prevalence of brucellosis in Macenta and Yomou was 12 and 5.33 %, respectively. In both provinces, the prevalence mean was 8.67 %. This study highlighted the immediate necessity to carry out a strengthened surveillance of human and animal brucellosis to obtain as many data as possible in order to establish strategies for prevention and management of brucellosis in Guinea. 相似文献
10.
The present study, using RAPD analysis, was undertaken to characterize genetic variation in domesticated cowpea and its wild progenitor, as well as their relationships. The materials used consisted of 26 domesticated accessions, including accessions from each of the five cultivar-group, and 30 wild/weedy accessions, including accessions from West, East and southern Africa. A total of 28 primers generated 202 RAPD bands. One hundred and eight bands were polymorphic among the domesticated compared to 181 among wild/weedy cowpea accessions. Wild accessions were more diverse in East Africa, which is the likely area of origin of V. unguiculata var. spontanea. Var. spontanea is supposed to have spread westward and southward, with a loss of variability, loss counterbalanceed in southern Africa by introgressions with local perennial subspecies. Although the variabilty of domesticated cowpea was the highest ever recorded, cultivar-groups were poorly resolved, and several results obtained with isozyme data were not confirmed here. However primitive cultivars were more diverse than evolved cultivars, which still suggests two consecutive bottlenecks within domesticated cowpea evolution. As isozymes and AFLP markers, although with a larger number of markers, RAPD data confirmed the single domestication hypothesis, the gap between wild and domesticated cowpea, and the widespread introgression phenomena between wild and domesticated cowpea. 相似文献