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61.
Barrouin-Melo SM Larangeira DF de Andrade Filho FA Trigo J Julião FS Franke CR Palis Aguiar PH Conrado dos-Santos WL Pontes-de-Carvalho L 《Veterinary journal (London, England : 1997)》2006,171(2):331-339
The purpose of this study was to evaluate the safety of spleen aspiration as a sampling technique for the parasitological detection by culture and microscopy of Leishmania (chagasi) infantum. Two hundred and nine domiciled dogs from an endemic area for visceral leishmaniasis in Bahia State, Brazil, were studied. Most dogs (87%) were seropositive for anti-L. chagasi antibodies by ELISA. Clinical signs of disease were recorded and the animals monitored during and after spleen puncture in order to detect possible complications associated with the procedure. From a total of 257 splenic punctures in the 209 animals, only three minor events occurred, with no significant consequence for the animals and no association with risk factors. Leishmania was isolated from 149/180 (83%) seropositive dogs, and from 6/26 (23%) seronegative animals. The procedure did not cause adverse side effects or unnecessary suffering and confirmed the diagnosis in a large percentage of dogs. We conclude that spleen aspiration can be considered an effective and safe procedure for the definitive diagnosis of canine visceral leishmaniosis. 相似文献
62.
D Grace M Dipeolu J Olawoye E Ojo S Odebode M Agbaje G Akindana T Randolph 《Tropical animal health and production》2012,44(Z1):61-66
We evaluated a group-based, participatory training intervention to improve food safety among meat processors and retailers in Bodija Market, Ibadan, Nigeria. An interactive training workshop was held for Butchers Associations' representatives who were selected to pass on information and training to their group. Meat hygiene knowledge, attitude and practice was assessed before attending the workshop and afterwards (n?=?63). It was also assessed for those who did not attend the workshop (n?=?68) but were intended recipients of training through their association. Microbiological quality of meat was assessed before and after the workshop (n?=?400 samples). After the workshop, participants significantly improved knowledge, attitude and practice in key food safety aspects; specifically, understanding sources of contamination and food-borne diseases, use of bleach and disinfectant and hand washing. Participants also shared information with an average of 18 other group members and improvements were seen in group members who did not attend the workshop but received training through their Butchers Association. Microbiological quality of meat sold also significantly improved after the intervention. In conclusion, participatory, group-based methods targeted at meat processors and retailers can improve meat hygiene knowledge, attitude and practice as well as the microbiological quality and hence safety of meat. 相似文献
63.
Grace Delia Olowoye Janice Dipeolu Morenike Odebode Stella Randolph Thomas 《Tropical animal health and production》2012,45(1):53-57
Four Newcastle disease virus isolates were recovered from asymptomatic guinea fowl (Numida meleagris galeata) and Muscovy ducks (Cariana moscata). For the purpose of molecular identification and phylogeny, phylogenetic characterization was performed to identify the pathotypes. All four viruses had a cleavage motif 112RRQKRF117 which is characteristic of virulent strains. The isolates grouped with viruses previously reported as sub-lineage 5g from chickens in Nigeria. This study report for the first time the identification of the virulent sub-lineage 5g Newcastle disease virus from apparently healthy guinea fowl and domestic ducks in Nigeria, and since infections were sub-clinical, it suggest that these species could play a role in the spread and transmission of virulent Newcastle disease virus that can infect other poultry. The isolation and identification of virulent Newcastle disease virus in these unusual hosts and the high sequence similarity (99.3–100 %) between viruses in this study with strains reported for Niger and Cameroun gives insights into the ecology of virulent Newcastle disease viruses and suggests some cross-border movement and trade in live poultry. 相似文献
64.
65.
Florent Noulekoun Emiru Birhane Stella Chude Amanuel Zenebe 《Agroforestry Systems》2017,91(1):123-135
Concerns about sustainable management and conservation of multipurpose trees in their habitat have led to increased number of studies on the ecological characterization of their population. Such knowledge on Faidherbia albida, the most used tree in agroforestry parklands in Ethiopia, is limited. F. albida population was characterized in and compared between two agroforests having different conservation status in Northern Ethiopia. Population structural parameters along with environmental factors and human activities were assessed in 42 randomly installed plots using a transect method. Size class distribution was used to describe and analyze the species long-term population dynamics. Adult density was almost three times higher in Zongi agroforest (19.9 ± 2.9 trees ha?1) where the species has been conserved and managed for longer time compared to Abraha-atsbeha agroforest (7.9 ± 2.5 trees ha?1). The same trend was observed for tree morphological parameters which were significantly higher at Zongi than Abraha-atsbeha. However, size class distributions coefficient of skewness and the median diameter indicated a declining and vulnerable population at Zongi and an increasing population at Abraha-atsbeha. Species population characteristics were influenced by environmental factors such as altitude, stone cover, erosion severity, slope, and human-related disturbances including land use, fodder harvesting, distance away from the center of the village and proximity of household to the plots. The study confirms the impact of conservation, environmental factors and human disturbances on shaping F. albida population and recommends the consideration of the trade-offs between them to design effective conservation and management strategies to sustain F. albida agroforests. 相似文献
66.
Garneau P Labrecque O Maynard C Messier S Masson L Archambault M Harel J 《Zoonoses and public health》2010,57(Z1):94-99
As diagnostic and surveillance activities are vital to determine measures needed to control antimicrobial resistance (AMR), new and rapid laboratory methods are necessary to facilitate this important effort. DNA microarray technology allows the detection of a large number of genes in a single reaction. This technology is simple, specific and high-throughput. We have developed a bacterial antimicrobial resistance gene DNA microarray that will allow rapid antimicrobial resistance gene screening for all Gram-positive and Gram-negative bacteria. A prototype microarray was designed using a 70-mer based oligonucleotide set targeting AMR genes of Gram-negative and Gram-positive bacteria. In the present version, the microarray consists of 182 oligonucleotides corresponding to 166 different acquired AMR gene targets, covering most of the resistance genes found in both Gram-negative and -positive bacteria. A test study was performed on a collection of Staphylococcus aureus isolates from milk samples from dairy farms in Québec, Canada. The reproducibility of the hybridizations was determined, and the microarray results were compared with those obtained by phenotypic resistance tests (either MIC or Kirby-Bauer). The microarray genotyping demonstrated a correlation between penicillin, tetracycline and erythromycin resistance phenotypes with the corresponding acquired resistance genes. The hybridizations showed that the 38 antimicrobial resistant S. aureus isolates possessed at least one AMR gene. 相似文献
67.
Petrakis PV Agiomyrgianaki A Christophoridou S Spyros A Dais P 《Journal of agricultural and food chemistry》2008,56(9):3200-3207
This work deals with the prediction of the geographical origin of monovarietal virgin olive oil (cv. Koroneiki) samples from three regions of southern Greece, namely, Peloponnesus, Crete, and Zakynthos, and collected in five harvesting years (2001-2006). All samples were chemically analyzed by means of 1H and 31P NMR spectroscopy and characterized according to their content in fatty acids, phenolics, diacylglycerols, total free sterols, free acidity, and iodine number. Biostatistical analysis showed that the fruiting pattern of the olive tree complicates the geographical separation of oil samples and the selection of significant chemical compounds. In this way the inclusion of the harvesting year improved the classification of samples, but increased the dimensionality of the data. Discriminant analysis showed that the geographical prediction at the level of three regions is very high (87%) and becomes (74%) when we pass to the thinner level of six sites (Chania, Sitia, and Heraklion in Crete; Lakonia and Messinia in Peloponnesus; Zakynthos). The use of classification and binary trees made possible the construction of a geographical prediction algorithm for unknown samples in a self-improvement fashion, which can be readily extended to other varieties and areas. 相似文献
68.
The ability to regulate gene expression throughout the course of an infection is important for the survival of a pathogen in the host. Thus, virulence gene expression responds to environmental signals in many complex ways. Frequently, global regulatory factors associated with specific regulators co-ordinate expression of virulence genes. In this review, we present well-described regulatory mechanisms used to co-ordinate the expression of virulence factors by pathogenic Escherichia coli with a relative emphasis on diseases caused by E. coli in animals. Many of the virulence-associated genes of pathogenic E. coli respond to environmental conditions. The involvement of global regulators, including housekeeping regulons and virulence regulons, specific regulators and then sensor regulatory systems involved in virulence, is described. Specific regulation mechanisms are illustrated using the regulation of genes encoding for fimbriae, curli, haemolysin and capsules as examples. 相似文献
69.
Angel Ripplinger Stella Maris Pereira de Melo Dênis Antonio Ferrarin Marcelo Luís Schwab Mathias Reginatto Wrzesinski Júlia da Silva Rauber Mariana Martins Flores Glaucia Denise Kommers Alexandre Mazzanti 《Journal of veterinary science (Suw?n-si, Korea)》2022,23(2)
This report aims to describe the first case of muscular and collagenous choristoma in a dog. A 10-yr-old female mixed-breed dog presented with lateral recumbence, vocalization, positional vertical nystagmus, divergent strabismus, anisocoria, and status epilepticus. The clinical condition evolved to stupor and ultimately, death. Necropsy revealed a white mass causing an irregular increase in the volume of the cerebellar vermis. In histological analysis, a well circumscribed, unencapsulated mass was observed in the cerebellum, consisting of fibers of striated skeletal muscle and collagen fibers, mostly mineralized. Based on the histopathological and histochemical findings, a diagnosis of muscular and collagenous cerebellar choristoma was made. 相似文献
70.
Based on recent mining rates and the exhaustion of global phosphorus(P)reserves,there is a need to mobilize P already stored in soils,and its recovery from secondary resources such as Ca-and Fe-phosphates is important.The Ca-phosphate hydroxyapatite forms a good fertilizer source,while vivianite is formed in waterlogged soils and sediments.During sludge treatment,the formation of vivianite has been identified,being mainly Fe-phosphate.Long-term P release from both hydroxyapatite and vivianite was studied using different inorganic(CaCl2 and CaSO4)and organic(citric and humic acid)reagents during batch experiments.Reagents CaCl2 and CaSO4 represent the soil solution,while citric and humic acids as organic constituents affect P availability in the rhizosphere and during the process of humification.Additionally,the flow-through reactor(FTR)technique with an infinite sink was used to study the long-term P release kinetics.The cumulative P release was higher by organic acids than by inorganic compounds.The cumulative P release rates were higher in the FTR with CaCl2 as compared to the batch technique.The infinite sink application caused a continuously high concentration gradient between the solid and liquid phases,leading to higher desorption rates as compared to the batch technique.The predominant amount of the total P released over time was available for a short term.While inorganic anion exchange occurred at easily available binding sites,organic acids affected the more heavily available binding sites,which could be embedded within the mineral structure.The results showed that organic compounds,especially citric acid,play a superior role as compared to the inorganic constituents of the soil solution during the recovery of already stored P from the tertiary phosphates vivianite and hydroxyapatite. 相似文献