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Pathogenicity of FtsK mutant of avian pathogenic Escherichia coli Full text
2016
Xu, Xiaojing | Chen, Xiang | Gao, Song | Zhao, Lixiang
Introduction: Avian pathogenic Escherichia coli (APEC) is a leading cause of extraintestinal infection and heavy economic losses. Imparting immunity after vaccination with live attenuated strain vaccination is an ideal strategy for infection control. This study considers an FtsK knockout mutant strain as a candidate. Material and Methods: An FtsK knockout mutant of APEC strain E058 was constructed and the pathogenicity of the mutant and wild-type strains was further evaluated in chickens. Results: The 50% lethal doses of each strain for one-day-old specific-pathogen-free (SPF) chickens challenged experimentally via trachea were 10⁵.⁵ and 10⁷.⁰ colony-forming units (CFU) respectively. Chickens challenged with the wild-type strain exhibited typical signs and lesions of avian colibacillosis, while those inoculated with the mutant strain showed mild pericarditis and pulmonary congestion. The growth rate of the FtsK mutant strain was much slower than the wild-type strain in the heart, spleen, liver, and lung of infected chickens. Conclusion: These results indicated that the APEC FtsK mutant can be attenuated for chickens, and that this mutant has the potential for the development of an APEC vaccine.
Show more [+] Less [-]Real-time quantitative PCR for detection and identification of Actinobacillus pleuropneumoniae serotype 2 Full text
2016
Dors, Arkadiusz | Kowalczyk, Andrzej | Pomorska-Mól, Małgorzata
Introduction: Porcine pleuropneumonia inflicts important economic losses on most commercial herds. Detection of subclinical or chronic infection in animals still remains a challenge, as isolation and identification of A. pleuropneumoniae serotypes is difficult and quantification of the bacteria on agar plates is often almost impossible. The aim of the study was to develop and evaluate a serotype-specific quantitative TaqMan probe-based PCR for detection of serotype 2 in pig lungs, tonsils, and nasal swabs.Material and Methods: The primers were designed from the capsular polysaccharide biosynthesis genes of A. pleuropneumoniae serotype 2. PCR specificity and sensitivity were evaluated using reference strains and several other bacterial species commonly isolated from pigs.Results: The real-time qPCR for detection of A. pleuropneumoniae serotype 2 was highly specific and gave no false positives with other serotypes or different bacterial species of pig origin. The detection limit for pure culture was 1.2 × 10⁴ CFU/mL, for lung tissue and nasal swabs it was 1.2 × 10⁵ CFU/mL, and for tonsils - 1.2 × 10⁵ CFU/mL.Conclusion: The method can be used to serotype A. pleuropneumoniae isolates obtained during cultivation and to detect and identify A. pleuropneumoniae serotype 2 directly in nasal swabs and tonsil scrapings obtained from live pigs or lung tissue and tonsils collected post-mortem.
Show more [+] Less [-]Epidemiological and histopathological analysis of 40 apocrine sweat gland carcinomas in dogs: a retrospective study Full text
2016
Kycko, Anna | Jasik, Agnieszka | Bocian, Łukasz | Otrocka-Domagała, Iwona | Mikiewicz, Mateusz | Smiech, Anna | Łopuszyński, Wojciech | Dolka, Izabella | Nowak, Marcin | Madej, Janusz A.
Introduction: Apocrine sweat gland carcinomas (ASGCs) are malignant neoplasms of dogs and other animals, rarely reported worldwide. The aim of this study was to summarise the occurrence of this cancer in a population of dogs in Poland between 2009 and 2014 with regards to histological features and body location of the tumours, as well as age, sex and breed of the cancer-affected dogs.Material and Methods: The study involved 40 canine ASGC cases diagnosed in five national veterinary pathology laboratories. The material was processed according to routine histological methods.Results: Histological types of the tumours involved simple and complex apocrine carcinoma of cystic/papillary (62.5%), solid (15%), and tubular type (12.5%), as well as apocrine ductal carcinoma (10%). The epidemiological analysis revealed peak incidence of the cancer in dogs between 8 and 14 years of age, with the most commonly affected sites being forelimbs and thorax. The highest number of the cancer cases was diagnosed in mixed breed dogs and German Shepherds; no sex predilection was noted.Conclusion: To the authors’ knowledge, this is the first report recounting the study on canine malignant apocrine sweat gland tumours in Poland providing detailed phenotypical and histological data, which are otherwise rarely described in veterinary literature. This type of cancer appears to be diagnosed more frequently in dogs than in humans. Being an easily accessible material for research, canine ASGCs might serve as a relevant animal model for studies related to pathogenesis of sweat gland tumours.
Show more [+] Less [-]Anti-fertility effect of hydro-alcoholic extract of fennel (Foeniculum vulgare Mill) seed in male Wistar rats Full text
2016
Introduction: The study aimed to investigate the anti-fertility effect of fennel (Foeniculim vulgare Mill) seed extract in male rats.Material and Methods: Forty Wistar rats were divided into five equal groups. The control group received distilled water and the experimental groups were orally administered 1 ml of hydro-alcoholic extract of fennel seed in four doses of 35, 70, 140, and 280 mg/kg/b.w. daily for 60 days. After the last gavage, the rats were anaesthetised and the caudal part of the right epididymis was used for sperm counting. After fixation of the testes, microscopic sections were prepared and histological changes were evaluated.Results: The number of spermatogonia after doses of 140 and 280 mg/kg and Sertoli cells after a dose of 140 mg/kg decreased significantly as compared with the control group (P < 0.05). The number of primary spermatocytes and sperm count decreased significantly in the experimental groups (70, 140, and 280 mg/kg) when compared to the control group (P < 0.05). Furthermore, thickening of the basement membrane, cell apoptosis, and irregular arrangement of the germinal epithelium were observed in the experimental groups.Conclusion: Hydro-alcoholic fennel seed extract at these doses could reduce reproductivity and has anti-fertility activity in male rats.
Show more [+] Less [-]Variations of selected trace element contents in two layers of red deer antlers Full text
2016
Giżejewska, Aleksandra | Nawrocka, Agnieszka | Szkoda, Józef | Żmudzki, Jan | Jaroszewski, Jerzy | Giżejewski, Zygmunt
Introduction: Hard antlers of deer are unique bioindicators of environmental metal pollutions, but sampling methods presented in the literature are inconsistent. Due to the specific growth pattern of antlers and their histological structure, sampling methods described in the literature were reviewed, the suitability of using mixed samples of both antler layers as element bioindicators was assessed, and the codified method of antler sampling used for bioindication was described. Material and Methods: Lead, cadmium, mercury, arsenic, copper, zinc, and iron in trabecular and cortical parts of hard antlers of red deer (Cervus elaphus) were determined using different methods of atomic absorption spectrometry (depending on the element). Results: Mean mercury content in trabecular bone (0.010 ±0.018 mg/kg) was 5 times higher than in cortical bone (0.002 ±0.003 mg/kg). Mean iron concentration was approximately 15 times higher in trabecular (239.83 ±130.15 mg/kg) than in cortical bone (16.17 ±16.44 mg/kg). Concentrations of other analysed elements did not differ statistically between antler layers. Conclusion: In mixed antler samples, concentrations of mercury and iron depend on the particular antler layer contents. This therefore warrants caution when comparing results across studies and specification of the sampling methodology of antlers is highly recommended.
Show more [+] Less [-]Red foxes (Vulpes vulpes) as reservoirs of respiratory capillariosis in Serbia Full text
2016
Ilić, Tamara | Becskei, Zsolt | Tasić, Aleksandar | Stepanović, Predrag | Radisavli︠e︡vich Katarina, | Đurić, Boban | Dimitrijević, Sanda
Introduction: The aim of the study was to determine the prevalence of respiratory capillariosis in red foxes (Vulpes vulpes) in some regions of Serbia.Material and Methods: The study was conducted on 102 foxes in six epizootiological regions of Serbia, during the hunting season between 2008 and 2012.Results: The presence of respiratory capillariosis in all tested epizootiological regions was confirmed. The E. aerophilus nematode was detected with overall prevalence of 49.02%. The diagnosis of E. aerophilus infection was confirmed by the determination of morphological characteristics of adult parasites found at necropsy and the trichurid egg types collected from the bronchial lavage and the content of the intestine.Conclusion: The presented results contribute to better understanding of the epidemiology of this nematodosis in Serbia. However, the high prevalence of capillaries in tested foxes, demonstrated in all explored areas, might suggest that foxes from other regions in Serbia may also be infected. The fact that domestic carnivores and humans can also be infected enhances the importance of the overall epidemiological status. To establish the relevant prevalence of respiratory capillariosis, further investigations and continous monitoring of parasitic fauna of carnivores are needed in the whole country.
Show more [+] Less [-]Identification of novel pathways in pathogenesis of ketosis in dairy cows via iTRAQ/MS Full text
2016
Shu, Shi | Xu, Chuchu | Xia, Cheng | Xiao, Xinhuan | Wang, Gang | Fan, Ziling | Cao, Yu | Wang, Yanhui | Zhang, Hongyou
Introduction: To identify novel pathways involved in the pathogenesis of ketosis, an isobaric tag for relative and absolute quantitation/mass spectrometry was used to define differences in protein expression profiles between healthy dairy cows and those with clinical or subclinical ketosis.Material and Methods: To define the novel pathways of ketosis in cattle, the differences in protein expression were analysed by bioinformatics. Go Ontology and Pathway analysis were carried out for enrich the role and pathway of the different expression proteins between healthy dairy cows and those with clinical or subclinical ketosis.Results: Differences were identified in 19 proteins, 16 of which were relatively up-regulated while the remaining 3 were relatively down-regulated. Sorbitol dehydrogenase (SORD) and glyceraldehyde-3-phosphate dehydrogenase (G3PD) were up-regulated in cattle with ketosis. SORD and G3PD promoted glycolysis. These mechanisms lead to pyruvic acid production increase and ketone body accumulation.Conclusion: The novel pathways of glycolysis provided new evidence for the research of ketosis.
Show more [+] Less [-]Selected aspects related to epidemiology, pathogenesis, immunity, and control of African swine fever Full text
2016
Woźniakowski, Grzegorz | Frączyk, Magdalena | Niemczuk, Krzysztof | Pejsak, Zygmunt
African swine fever (ASF) is currently one of the most severe viral infections of domestic pigs, wild boars, and other hosts belonging to Suidae family. ASF is also considered as the most complex and devastating infectious and haemorrhagic disease of swine due to its severe socio-economic impact and transboundary character. ASF it is a notifiable disease and due to the lack of specific treatment and vaccine, the disease can be only limited by the administrative measures comprising wild boar hunting and stamping out of affected pigs. ASF occurred for the first time in Kenya in 1921 while in Europe (Portugal) the virus was detected at the end of the 1950s. In spite of successful eradication of this threat in a number of affected regions, the virus remains endemic in both feral and domestic pigs in Africa and Sardinia. The ‘new era’ of ASF started in 2007 after its re-introduction to Georgia. Following its intensive expansion, the virus spread to other Caucasian countries, including the territory of the Russian Federation. In 2014 the virus reached Ukraine, Belarus, and, consequently, European Union countries: Lithuania, Latvia, Estonia, and Poland. The occurrence of ASF in wild boars and pigs had a severe impact on both epidemiology and economy because of the national and international transport and trade consequences. Up to date, starting from the February 2014, eighty ASF cases in wild boar and three outbreaks in domestic pigs have been diagnosed. Taking into account the diverse rate of spread in Poland, this review aims to present and discuss the current state of knowledge on ASF including its epidemiology, pathology, transmission, and perspectives of control.
Show more [+] Less [-]Pharmacokinetic - pharmacodynamic model and ampicillin residue depletion after intramammary administration in cows Full text
2016
Burmańczuk, Artur | Roliński, Zbigniew | Kowalski, Cezary | Zań, Rafał
Introduction: The objective of this study was to describe a pharmacokinetic–pharmacodynamic (PK/PD) approach for determination of a rational dosage of ampicillin (AMP) and depletion of the antibiotic residues in milk after intramammary administration to cows.Material and Methods: The cows came from different farms from the Lublin Province area. They (n = 9) received 5 g of the drug, containing 75 mg of AMP sodium in physiological solution, through a syringe tube by intramammary administration. Following single intramammary administration, the milk samples (5 mL) were collected after 2, 4, 6, 8, 10, 24, 36, 48, and 60 h. The liquid chromatography-mass spectrometry analysis was performed on the Agilent 1200 system connected to an AB Sciex API 4000™ mass spectrometer. The pharmacokinetic analysis of the concentrations of the antibiotic in milk was performed using software Phoenix® WinNonlin® 6.4. Calculations were made in non-compartmental (slopes, highest, amounts, and moments) and compartmental analysis.Results: The pharmacokinetic characteristics of AMP after intramammary administration indicate rapid elimination of the drug from milk. The mean residence time had a several-fold lower value than the designated elimination half-life and amounts to only 3.4 h. The concentration of the drug in the milk dropped relatively quickly and the process was very dynamic.Conclusion: The conducted research confirms the rationale of using the PK/PD model in order to verify the dosing regimen for other antibiotic groups and various indicators of the applied PK/PD model.
Show more [+] Less [-]Preliminary study on the detection of hepatitis E virus (HEV) antibodies in pigs and wild boars in Poland Full text
2016
Weiner, Marcin | Tokarska-Rodak, Małgorzata | Plewik, Dorota | Pańczuk, Anna | Szepeluk, Adam | Krajewska, Monika
Introduction: Although HEV infection in pigs does not pose a major economic risk to pork production, the risk of zoonotic transmission to humans is an important aspect of public health. HEV genotype 3 infections were reported in developed countries in individuals who had consumed raw meat or meat products from deer, wild boars, or pigs. The aim of the study was the analysis of the occurrence of HEV-specific antibodies among wild boars and domestic pigs in Poland. Material and Methods: A total of 290 samples from wild boars and 143 samples from pigs were tested. The antibodies were tested by ELISA. Results: The presence of anti-HEV IgG was demonstrated in 44.1% of pigs and 31.0% of wild boars. Anti-HEV IgG antibodies were detected in 1.4% of samples from pigs and in 2.1% of samples from wild boars at borderline level. The statistical analysis shows significant differences in the positive results for anti-HEV IgG between the groups of pigs and wild boars (P = 0.0263). Conclusion: Regular surveillance of the occurrence of HEV in swine and wild boars should be performed in the future.
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