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71.
Species of Naegleria, Acanthamoeba, and Balamuthia are soil amoebae that can cause encephalitis in animals and humans. Of these, Naegleria fowleri is the cause of often fatal primary meningoencephalitis in humans. N. fowleri-associated encephalitis was diagnosed in a cow that was suspected to have rabies. Only formalin-fixed brain was available for diagnosis. There was severe meningoencephalitis involving all parts of the brain and numerous amoebic trophozoites were present in lesions. The amoebae reacted with N. fowleri-specific polyclonal antibodies in an indirect immunofluorescent antibody test. This is the first report of amoebic encephalitis in any host from Costa Rica. 相似文献
72.
Downy mildew (DM) caused by Peronospora arborescens is the most destructive disease of opium poppy which assumes considerable importance in India and other poppy growing countries.
The present study was aimed at identification and evaluation of stable resistance sources of DM in opium poppy. Furthermore,
genetic variability and inheritance pattern of DM resistance has also been studied which can help in making strategy for crop
improvement. Evaluation of 35 selected germplasm accessions of opium poppy under glasshouse and field conditions during the
three consecutive years (2004–2005 to 2006–2007) resulted in identification of two genotypes (I-14 and Pps-1) as highly resistant
and stable sources for DM resistance. Genetic studies of DM resistance revealed polygenic control with the dominance of susceptibility
over resistance. Significant reciprocal differences were found largely due to maternal transmission of DM resistance indicating
the involvement of cytoplasmic genes in addition to nuclear control. Analysis of genetic variability and selection parameters
indicated predominance of additive effects for DM resistance and other yield contributing traits. Multivariate analysis resulted
in classification of 35 selected accessions into 11 different clusters revealing very high level of diversity among the genotypes.
Cluster analysis suggested that hybridization program involving genotypes from cluster V (which included highly resistant
genotypes Pps-1 and I-14) and cluster IX (which included highly susceptible Jawahar-16 having good economically important
traits like seed yield) could be expected to give best recombinants for improvement in terms of DM resistance and high seed
and straw yield in opium poppy. Analysis of selection parameters like heritability and genetic advance also suggested that
simple selection methods will be effective in stabilizing resistance traits following hybridization with high yielding genotypes. 相似文献
73.
J. P. Dubey 《Zoonoses and public health》2010,57(1):60-73
Chickens are considered one of the most important hosts in the epidemiology of Toxoplasma gondii infection because they are an efficient source of infection for cats that excrete the environmentally resistant oocysts and because humans may become infected with this parasite after eating undercooked infected chicken meat. The objective of this study is to review worldwide prevalence of T. gondii infection in chickens and to assess the role of infected chickens in the epidemiology of toxoplasmosis in humans. A very high prevalence of the parasite was found in chickens raised in backyards (up to 100%) and free‐range organic (30–50%) establishments. 相似文献
74.
The United States Department of Agriculture (USDA) initiated the National Animal Health Monitoring System (NAHMS) in 1983 to collect, analyse and disseminate data on animal health, management and productivity in US domestic livestock populations, including swine. The programme includes an on‐farm serological sampling component which can be used to monitor seroprevalence of various pathogens, including Toxoplasma gondii. The purpose of this study was to determine the seroprevalence of T. gondii in grower/finisher pigs using sera collected during NAHMS Swine 2006 and to determine farm level factors associated with differences in seroprevalence on farms where sera was collected during the Swine 2006 survey. Sera and data on management practices for this study were collected from 185 grower/finisher swine production sites located in 16 states accounting for >90% of US swine production (Arkansas, Colorado, Iowa, Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Carolina, Ohio, Pennsylvania, South Dakota, Texas and Wisconsin). A total of 6238 sera were tested for T. gondii antibodies using a commercial ELISA assay (Vet. Parasitol. 128 , 2005, 177). Seroprevalence in this study, as determined by ELISA, was 2.6%, with a herd prevalence of 21.6% and a mean within‐herd prevalence of 2.7%. Analysis of swine management practices indicated that rodent control methods and carcass disposal methods were associated with differences in the number of T. gondii positive samples on farm. These results are consistent with current epidemiological knowledge of the transmission of Toxoplasma on the farm (ingestion of organic matter containing oocysts, or ingestion of infected animal tissues). Production practices which eliminate these sources of exposure can reduce the risk of Toxoplasma infection in pigs, and reduce the likelihood of human infection from consumption of infected pork. 相似文献
75.
Soil salinity diminishes soil health and reduces crop yield, which is becoming a major global concern. Salinity stress is one of the primary stresses, leading to several other secondary stresses that restrict plant growth and soil fertility. The major secondary stresses induced in plants under saline-alkaline conditions include osmotic stress, nutrient limitation, and ionic stress, all of which negatively impact overall plant growth. Under stressed conditions, certain beneficial soil microflora ... 相似文献
76.
Antifungal properties of Ocimum gratissimum essential oil (ethyl cinnamate chemotype). 总被引:3,自引:0,他引:3
Largely widespread in tropical countries, Ocimum gratissimum has been claimed for many uses in folk medicine. Recent research on its essential oils showed five chemotypes. An Indian chemotype, with a high level of ethyl cinnamate, presents, in vitro, an interesting spectrum of antifungal properties. 相似文献
77.
78.
Transplacental Neospora caninum infection in dogs 总被引:3,自引:0,他引:3
A Beagle bitch was inoculated SC and IM with 1.5 million Neospora caninum tachyzoites on the 35th day of gestation. Eight pups were born alive 28 days after N caninum inoculation of the bitch. Pup 1 did not breathe and died while still enclosed in fetal membranes. Pup 2 died 2 days after birth (DAB). Pups 3, 4, and 5 were euthanatized on 2, 3, and 20 DAB, respectively, because they were hypothermic and not nursing. Pups 6, 7, and 8 remained clinically normal. Indirect fluorescent N caninum serum antibody titers were: less than 50 (pups 1 and 8 at 17 DAB, and the bitch before inoculation), 50 (pups 2 and 3 on 2 DAB), 200 (pups 6 and 7 on 17 DAB), and 800 (bitch on day 17 after parturition). Neospora caninum was recovered in cultured cells inoculated with placenta and tissues from all 5 pups necropsied, and N caninum was seen in histologic sections of the heart of pup 5. Results indicate that N caninum can be transplacentally transmitted in dogs. 相似文献
79.
J R Heidel J P Dubey L L Blythe L L Walker J R Duimstra J S Jordan 《Journal of the American Veterinary Medical Association》1990,196(2):316-318
Severe necrotizing myelitis secondary to localization and reactivation of Toxoplasma gondii within the spinal cord of a domestic shorthair cat was diagnosed by use of light and electron microscopy and immunohistochemistry. The cat also was infected with feline immunodeficiency virus. This case may have useful comparative features to T gondii infections in human patients with acquired immunodeficiency syndrome. 相似文献
80.
Sixteen 50 day gestational ewes were fed lasalocid at the rate of 30 g t-1 and were orally inoculated with 100 infective Toxoplasma gondii oocysts 5 days after beginning feeding of lasalocid. Seventeen control ewes were similarly inoculated with T. gondii and were not fed lasalocid. The rate of abortion and neonatal mortality in both treated and untreated ewes was similar, indicating that feeding lasalocid was not effective in preventing T. gondii abortion in sheep. 相似文献