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991.
Niczyporuk JS Samorek-Salamonowicz E Kozdruń W Mizak Z 《Acta veterinaria Hungarica》2011,59(3):405-408
The aim of the study was to attempt the detection of West Nile virus (WNV) in wild birds in Poland. Forty-eight species of 1912 wild birds were used for the investigations. The birds were derived from various locations in Poland from early spring till late autumn of the years 2009-2011. The brain samples were homogenised and cellular RNA was isolated. Two methods (RT-PCR and nested RT-PCR) were used. The presence of WNV RNA was not detected in the samples examined. Additionally, a short analysis of the epizootiological situation regarding the presence of WNV in Poland is presented. 相似文献
992.
Some aspects of the biology of the tick Hyalomma anatolicum fed on rabbits, sheep and goats were studied. The non-feeding stages were maintained under laboratory conditions at 20-36°C and 75% relative humidity. The longest feeding periods of larvae and nymphs of H. anatolicum were observed when fed on rabbits (mean 4.58 ± 0.51 and 7 ± 1.15 days, respectively) while the longest feeding periods of females were observed on goats (9.61 ± 1.21). The pre-oviposition period (4.8 ± 0.42 days) and pre-eclosion periods (mean 21.3 ± 1.16 days) were shortest for females fed on rabbits. Engorged females reached heavier engorgement weights (482.92 ± 88.08 mg), and produced more eggs (4881.8 ± 842.71) when fed on rabbits. However, no significant differences were observed between the percentages hatchability of eggs laid by ticks fed on the three hosts studied. Most (94.31%) of the larvae fed on rabbits underwent a 2-host life cycle, while few (5.69%) of them behaved as a 3-host ticks. Few larvae were able to complete feeding as 3-host pattern on both sheep and goats, while the majority of the larvae failed to complete feeding or died on their way to molt on both sheep and goats. 相似文献
993.
El-Dakhly KM El-Nesr KA El-Nahass el-S Hirata A Sakai H Yanai T 《Tropical animal health and production》2011,43(8):1549-1554
This study was performed for the purpose of investigating the prevalence of Sarcocystis spp. in buffaloes in Beni-Suef Governorate, Egypt. Both macroscopic (Sarcocystis fusiformis) and microscopic (Sarcocystis levinei) cysts were recognized, and were differentiated by their morphological features and location in the tissues. Of 379 buffaloes
examined in abattoirs in Beni-Suef, 299 were found to be infected, with an overall prevalence of 78.9%. Depending on age,
three categorized groups of naturally infected buffaloes were examined: male buffalo calves aged 1.5–2 years, adult females
aged 2–5 years, and females older than 5 years. Among these groups, infection rates were 74.5%, 82.3%, and 81.2%, respectively.
Organs examined included esophagus, tongue, and heart. Macroscopic cysts were examined by the naked eye through meat inspection
in abattoirs, while the pepsin-digestion method and the histological technique were applied to detect microscopic cysts. It
has been found that esophagus showed the highest rate of infection among the infected organs, with both macroscopic and microscopic
cysts seen in the infected buffaloes. Moreover, results of the pepsin-digestion method proved more accurate than those produced
by the histological technique in terms of infection rates for the microscopic cysts. Our findings indicated that infected
buffaloes aged 2–5 years showed the highest mixed infection rate (82.3%) for both types of cysts. The high prevalence of microscopic
Sarcocystis spp. in Beni-Suef Governorate reflects a significant role played by stray dogs, rather than cats, in the transmission of
these parasites. 相似文献
994.
995.
Martínez-Martínez S Frandoloso R Gutiérrez-Martín CB Lampreave F García-Iglesias MJ Pérez-Martínez C Rodríguez-Ferri EF 《Veterinary immunology and immunopathology》2011,144(1-2):61-67
Haemophilus parasuis is the etiological agent of Gl?sser's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. This study was focused on the characterization of the acute-phase response after immunization and infection of colostrum-deprived pigs with H. parasuis serovar 5, by measuring serum concentrations of three positive acute-phase proteins (APPs) (pig major acute-phase protein pig, MAP; haptoglobin, HPG; C-reactive protein, CRP) and one negative APP (apolipoprotein A-I, ApoA-I). Six experimental groups were established: a non-immunized but infected control group (CTL); two groups immunized with either a recombinant transferrin-binding protein (Tbp) A or TbpB fragment from H. parasuis Nagasaki strain (rTbpA and rTbpB, respectively); two groups immunized with native outer membrane proteins with affinity to porcine transferrin (NPAPT), one of them inoculated intramuscularly (NPAPTim) and the other intratracheally (NPAPTit), and the last group receiving a commercially available bacterin (PG). The greatest concentrations of the three positive APPs and the lowest concentration of the negative APP were detected in CTL group, as well as in those animals belonging to rTbpA or rTbpB groups that died in response to challenge. Significant differences (P<0.005) were found in these groups when comparing challenge with the following days after it. However, no significant differences were seen for the remaining vaccinated groups (NPAPTim, NPAPTit and PG), which were effectively protected against Gl?sser's disease. Therefore, APPs could be used as useful biomarkers for both evaluating disease progression and determining vaccination effectiveness. 相似文献
996.
Lamien CE Le Goff C Silber R Wallace DB Gulyaz V Tuppurainen E Madani H Caufour P Adam T El Harrak M Luckins AG Albina E Diallo A 《Veterinary microbiology》2011,149(1-2):30-39
Sheep poxvirus (SPPV), Goat poxvirus (GTPV) and Lumpy skin disease virus (LSDV) are Capripoxviruses (CaPVs) responsible for causing severe poxvirus disease in sheep, goats and cattle, respectively. Serological differentiation of CaPVs is not possible and strain identification has relied on the implicitly accepted hypothesis that the viruses show well defined host specificity. However, it is now known that cross infections can occur and authentication of identity based on the host animal species from which the strain was first isolated, is not valid and should be replaced with molecular techniques to allow unequivocal strain differentiation. To identify a diagnostic target for strain genotyping, the CaPV homologue of the Vaccinia virus E4L gene which encodes the 30 kDa DNA-dependent RNA polymerase subunit, RPO30 was analyzed. Forty-six isolates from different hosts and geographical origins were included. Most CaPVs fit into one of the three different groups according to their host origins: the SPPV, the GTPV and the LSDV group. A unique 21-nucleotide deletion was found in all SPPV isolates which was exploited to develop a RPO30-based classical PCR test to differentiate SPPV from GTPV that will allow rapid differential diagnosis of disease during CaPV outbreaks in small ruminants. 相似文献
997.
Grazziotin AL Santos AP Guimaraes AM Mohamed A Cubas ZS de Oliveira MJ dos Santos LC de Moraes W Vieira RF Donatti L de Barros Filho IR Biondo AW Messick JB 《Veterinary microbiology》2011,152(3-4):415-419
Hemotrophic mycoplasmas (hemoplasmas) are bacteria that attach to red blood cells of mammals, leading to acute and/or subclinical disease in infected animals. It has been suggested that Mycoplasma ovis, a hemoplasma that infects sheep and goats worldwide, may also infect deer. The aim of this study was to evaluate whether South American deer are infected with M. ovis. EDTA-anticoagulated blood samples from a herd of 32 captive South American deer were collected. DNA extraction of blood samples was performed followed by PCR amplification of the 16S and 23S rRNA genes, and sequencing of products. Using M. ovis PCR, 27/31 (87%) were positive, including 21/22 Mazama nana; 2/3 Mazama americana and 4/6 Blastocerus dichotomus. Sequencing of the nearly entire 16S rRNA gene of 26/27 positive samples showed 98.2-98.8% identity to M. ovis of sheep (GenBank, AF338268) and 98.6-99.4% identity to M. ovis-like of a fawn (FJ824847); the 23S rRNA gene from one of these isolates and the fawn's had 97.6% identity. The remaining isolate had just 94.9% identity to the 16S rRNA gene of M. ovis and only 89.4% identity to the 23S rRNA gene of the fawn's M. ovis. This is the first report of M. ovis in captive South American deer, revealing a high prevalence of hemoplasma infection in these animals. 相似文献
998.
C.A. Batten B. Harif M.R. Henstock S. Ghizlane L. Edwards C. Loutfi C.A.L. Oura M. El Harrak 《Research in veterinary science》2011,90(3):533-535
Three camels aged 4–5 years were experimentally infected with Bluetongue virus serotype 1 (BTV-1) and were observed for 75 days. No clinical signs of disease were observed throughout the experiment, however all three animals seroconverted and developed BTV-1 specific neutralising antibodies after challenge. All three camels developed a viraemia from 7 days post infection albeit at a lower level than that usually observed in experimental infections of sheep and cattle. Virus was isolated from the blood of all three animals suggesting that camels may act as a reservoir for BTV and play an important role in its transmission. 相似文献
999.
1000.
BACKGROUND: Upon emergence from their pupal cells, bollworm, Helicoverpa zea (Boddie), adults actively seek and feed on plant exudates before they disperse and reproduce on suitable host plants. This nocturnal behavior of the bollworm may be exploited as a pest management strategy for suppression of the insect by using an attractant/stimulant mixed with an insecticide to induce feeding to cause adult mortality or reproductive reduction/inhibition. This study aimed to determine in the laboratory whether or not spinosad when mixed with sucrose solution as a feeding stimulant and ingested by bollworm could influence mortality and reproduction of the insect. RESULTS: Sublethal concentrations of spinosad fed to laboratory‐reared females confined with males significantly reduced percentage hatch of eggs at 0.1 mg L?1, and it was reduced to near zero at 2.5 mg L?1 when compared with females fed 2.5 M sucrose solutions only. The lethal concentration (LC99) for males captured from the field in sex‐pheromone‐baited traps was 73 mg L?1 for 24 h response. Proboscis extension response was not inhibited significantly even at 10 g L?1. In spite of a 137‐fold increase in lethal dose concentration, spinosad did not inhibit feeding. CONCLUSION: A detailed study of laboratory‐reared and field‐collected bollworm adults relative to mortality and reproduction after ingestion of spinosad indicates that spinosad would be useful in an attract‐and‐kill strategy to control the insect when mixed with a feeding attractant/stimulant. Field validation of the data is warranted. Published 2010 by John Wiley & Sons, Ltd. 相似文献