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Genetic diversity of Campylobacter jejuni isolated from the poultry food chain
2019
Wieczorek, Kinga | Osek, Jacek
Introduction: Campylobacter jejuni is one of the most frequently reported causes of foodborne bacterial enteric disease worldwide. The main source of these microorganisms is contaminated food, especially of poultry origin. There are several molecular methods for differentiation of Campylobacter isolates at the subgenus level, and one of these is porA-typing based on the sequencing of the major outer-membrane protein (MOMP) encoding gene. The aim of the study was to test the molecular relationship of C. jejuni strains isolated at different points along the poultry food chain and assess the population structure of the isolates. Material and Methods: A total of 451 C. jejuni were used in the study, and a DNA fragment of 630 bp of the MOMP encoding gene was amplified and sequenced. Results: One hundred and ten sequence types were identified, with 69 (62.7%) unique to the isolates' origin and 30 not present in the database. The most prevalent nucleotide variant 1 was detected in 37 (8.2%) strains. These isolates were identified in all poultry sources tested, especially in faeces (15 isolates) but also in poultry carcasses and meat (11 isolates in each). Conclusion: The porA typing method was highly discriminative for C. jejuni of poultry origin since the Simpson's diversity index (D) achieved a value of 0.876, indicating considerable diversity in the bacterial population tested. The method may be further used for epidemiological investigation purposes.
Afficher plus [+] Moins [-]Clinical chemistry investigations in recumbent and healthy German Holstein cows after the fifth day in milk
2019
Weber, Jim | Zenker, Markus | Köller, Gábor | Fürll, Manfred | Freick, Markus
Recumbency is a frequent symptom occurring throughout lactation. Its cause can be related to the energy or mineral metabolism, or to trauma or infectious diseases. We compared various clinical chemistry parameters between healthy and recumbent cows and between cows with different causes of recumbency and determined if hypocalcaemia manifests in later lactation. Recumbent (n = 32) and healthy (n = 32) German Holstein cows were studied. After clinical examination, a serum sample was taken to measure the concentrations of Mg, Ca, Fe, Na, K, Pi, β-hydroxybutyrate, total bilirubin, non-esterified fatty acids (NEFA), urea, and creatinine as well as activities of alkaline phosphatase, aspartate aminotransferase (AST), creatine kinase (CK), and γ-glutamyl transferase in recumbent cows > 5 d in milk and control cows matched for age, lactation number, and pregnancy stage. In recumbent cows, mean serum concentrations of NEFA, bilirubin, and CK were statistically higher, while those of Fe, K, and Pi were significantly lower. Parameters compared between different recumbency diagnoses showed some descriptive Fe, K, urea, and AST differences, but these were not statistically significant. The results show that only a limited number of parameters have diagnostic besides therapeutic value. Although of minor importance in our study, hypocalcaemia should be considered a cause of recumbency, even outside the typical risk period of parturient paresis.
Afficher plus [+] Moins [-]Serological diagnosis of lentivirus infection in goats raised in Algeria
2019
Idres, Takfarinas | Lamara, Ali | Temim, Soraya | Boudjellaba, Sofiane | Gagnon, Jean | Chebloune, Yahia
Introduction: Infection of goats with caprine arthritis encephalitis virus (CAEV) has been detected in variable proportions in many countries all over the world. Here, we investigated the seroprevalence of CAEV in goats raised in Algeria. Material and Methods: A serological survey was performed on serum samples from 1,313 goats, including the local breeds (Arabia and Dwarf of Kabylia) and imported European breeds (Alpine and Saanen). Blood samples were taken from goats on 38 farms distributed across four different geographical regions of Algeria. Serum samples were tested for CAEV antibodies using a commercial ELISA. Results: A total of 390 serum samples were found to be positive for CAEV, giving an overall seropositivity rate of 29.7% in individual animals and 97.37% (37/38) at the goat farm level. Conclusion: These results provide the first large-scale serological evidence for the presence of CAEV infection in both the local and imported breeds of goats raised in Algeria, indicating that the virus infection is widespread.
Afficher plus [+] Moins [-]In vitro evaluation of chitosan-DNA plasmid complex encoding Jembrana disease virus Env-TM protein as a vaccine candidate
2019
Ishak, Januar | Unsunnidhal, Lalu | Martien, Ronny | Kusumawati, Asmarani
Introduction: The development of Jembrana disease vaccine is an important effort to prevent losses in the Bali cattle industry in Indonesia. This study aims to prepare a Jembrana DNA vaccine encoding the transmembrane portion of the envelope protein in pEGFP-C1 and test the success of its delivery in culture cells using a chitosan-DNA complex. Material and Methods: Cloning of the DNA vaccine was successfully performed on E. coli DH5α and confirmed by colony PCR, restriction analysis and sequencing. The plasmids were prepared as a chitosan complex using the complex coacervation method and physicochemically characterised using a particle size analyser. A transfection assay was performed in HeLa cells with 4 h exposure, and mRNA expression was assessed at 24 h post transfection. Results: With a 1:2 (wt./wt.) ratio of DNA and chitosan, the complexes have a mean diameter of 236 nm, zeta potential value of + 17.9 mV, and showed no high toxicity potential in the HeLa cells. This complex successfully delivered the DNA into cells, as shown by the presence of a specific RT-PCR product (336 bp). However, the real-time PCR analysis showed that the delivery with chitosan complex resulted in lower target mRNA expression when compared with a commercial transfecting agent. Conclusion: pEGFP-env-tm JDV as a candidate vaccine can be delivered as the chitosan-DNA complex and be expressed at the transcription level in vitro. This initial study will be used for further improvement and evaluation in vivo.
Afficher plus [+] Moins [-]Evaluation of a canine transmissible venereal tumour cell line with tumour immunity capacity but without tumorigenic property
2019
Zayas, Yareellys Ramos | Molina, Moisés Armides Franco | Guerra, Reyes Tamez | Padilla, Cristina Rodríguez
Introduction: Canine transmissible venereal tumour (CTVT) is a sexually transmitted tumour affecting dogs worldwide, imposing a financial burden on dog owners. A stable culture cell line in continuous passages for >18 months has only been achieved once. The present study investigated a stable CTVT cell line isolated from a bitch and its potential as a vaccine. Material and Methods: A biopsy from a 2-year-old mongrel bitch with CTVT was obtained for histopathological confirmation and isolation of tumour cells. The isolated cells were cultured to passage 55 and characterised by flow cytometry, with karyotyping by GTG-banding and by PCR detection of myc S-2 and LINE AS1. The isolated CTVT cell line was also used as a preventive vaccine in a canine model. Results: Histopathological analysis of the isolated tumour cells revealed typical CTVT characteristics. Constant proliferation and stable morphological characteristics were observed during culture. Phenotypic analysis determined the expression of HLA-DR⁺, CD5.1⁺, CD14⁺, CD45⁺, CD83⁺, CD163⁺, and Ly-6G-Ly-6C⁺. GTG-banding revealed a mean of 57 chromosomes in the karyotype with several complex chromosomal rearrangements. LINE-c-myc insertion in the isolated CTVT cell line at 550 bp was not detected. However, a 340-bp band was amplified. Isolated CTVT cell line inoculation at a concentration of 1×10⁸ did not induce tumour growth in bitches, nor did a challenge with primary CTVT cells. Conclusion: The present study successfully identified and isolated a stable CTVT cell line that may be useful in CTVT prevention.
Afficher plus [+] Moins [-]Breeding profiles at the periparturient stage in captive red foxes (Vulpes vulpes) mating naturally or subjected to artificial insemination in Japan
2019
Yatu, Minoru | Satō, Mitsuhiro | Kobayashi, Jin | Ichijyo, Toshihiro | Satoh, Hiroshi | Oikawa, Toshinori | Sato, Shigeru
Introduction: Breeding profiles at the periparturient stage in red foxes which mated naturally or were subjected to artificial insemination were retrospectively surveyed using 130 vixens during their reproductive seasons of 2012–2017 in Japan. Material and Methods: Natural mating vixens were encouraged a maximum of three times with the same male, while artificial insemination was conducted using frozen-thawed semen with the bovine semen extender as a diluent. Results: With natural mating, conception rates after one, two, and three copulations were 55.8%, 68.0%, and 85.7%, respectively, showing a significant difference between the rates for one and three copulations. Conception rates with artificial insemination were 82.4%. Mean gestation periods were between 52.1 and 53.3 days in all groups. Mean litter sizes were 3.7–4.3 cubs with natural mating, and 4.4 cubs with artificial insemination. Although some sporadic and inconsistent changes in litter sizes were noted between primiparous and multiparous groups, these were of doubtful clinical importance. Conclusion: This is the first report from Japan concerning basic breeding events of red fox vixens in captivity.
Afficher plus [+] Moins [-]Evaluation of the possibility of C. burnetii transmission by the alimentary route in a guinea pig model
2019
Jodełko, Agnieszka | Szymańska-Czerwińska, Monika | Kycko, Anna | Niemczuk, Krzysztof
Q fever (coxiellosis) is an infectious disease of animals and humans, caused by.C. burnetii and widely distributed throughout the world. It is known that people and animals acquire the disease predominantly.via inhalation of infectious aerosols. The possibility of transmission of the pathogen by the alimentary route is still a matter of debate and remains controversial. Therefore the aim of this study was to fill the gaps in knowledge of oral transmission of.C. burnetii by conducting biological tests on the guinea pig model. Guinea pigs, divided into five groups comprising a negative control and four experimental groups, received specified concentrations of.C. burnetii per os. To determine the presence of specific antibodies, blood samples were tested using CFT. Also, internal organs collected during necropsy were screened by a real-time PCR targeting I.1111. Additionally, histopathological evaluation of the tissues was performed. The presence of antibodies and pathogen DNA in caecum was confirmed in one guinea pig from experimental group IV..C. burnetii was also detected in testicular tissue collected from one animal of experimental group II. The presence of pathogen DNA in the testicular tissue indicates that infection spreads haematogenously. In the majority of experimental animals specific antibodies and genetic material of.C. burnetii were not detected. This fact suggests that development of infection depends on many factors, such as animal immune status.
Afficher plus [+] Moins [-]ARTs in wild felid conservation programmes in Poland and in the world
2019
Kochan, Joanna | Niżański, Wojciech | Moreira, Nei | Cubas, Zalmir Silvino | Nowak, Agnieszka | Prochowska, Sylwia | Partyka, Agnieszka | Młodawska, Wiesława | Skotnicki, Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
Afficher plus [+] Moins [-]Identification and molecular characterisation of bovine parainfluenza virus-3 and bovine respiratory syncytial virus - first report from Turkey
2019
Timurkan, Mehmet Ozkan | Aydın, Hakan | Ahmet Sait,
Introduction: Bovine parainfluenza virus-3 (BPIV3) and bovine respiratory syncytial virus (BRSV) are the cause of respiratory disease in cattle worldwide. With other pathogens, they cause bovine respiratory disease complex (BRDC) in ruminants. The aim of the study was the detection and molecular characterisation of BPIV3 and BRSV from nasal swabs and lung samples of cows in and around the Erzurum region of eastern Turkey. Material and Methods: In total, 155 samples were collected. Of animals used in the study 92 were males and 63 females. The age of the animals was between 9 months and 5 years, mean 1.4 years. Most males were in the fattening period and being raised in open sheds; females were in the lactating period and kept in free stall barns. All samples were tested for the presence of viral genes using RT-PCR. Gene-specific primers in a molecular method (RT-PCR) identified BRSV (fusion gene) and BPIV3 (matrix gene) strains at the genus level. Results: RNA from BRSV and BPIV3 was detected in two (1.29%) and three (1.93%) samples, respectively, one of each of which was sequenced and the sequences were aligned with reference virus strains. Phylogenetic analyses clustered the strains in genotype C/BPIV3 and subgroup III/BRSV. Conclusion: The results indicate that BRSV and BPIV3 contribute to bovine respiratory disease cases in Turkey. This is the first report on their detection and molecular characterisation in ruminants in Turkey.
Afficher plus [+] Moins [-]Cytogenetic karyotype analysis in selected species of the Erinaceidae family
2019
Grzesiakowska, Anna | Baran, Przemysław | Kuchta-Gładysz, Marta | Szeleszczuk, Olga
Comparative analysis of the karyotype structure was made in two hedgehog species: the northern white-breasted hedgehog (Erinaceus roumanicus) and the African pygmy hedgehog (Atelerix albiventris). The cytogenetic analysis used differential staining techniques (DAPI, Ag-NOR, and C-banding/DAPI) and sequential QFQ/FISH banding with NOR20 and TEL20 probes which showed 45S rDNA and (TTAGGG)ₙ repeat sequences, respectively, on hedgehog chromosomes. It was confirmed that the somatic cells of the hedgehogs have a constant number of chromosomes (2n = 48,XY). Differences were observed in the NOR number between the species. NORs were identified on three autosome pairs in the northern white-breasted hedgehog and on only two pairs in the African pygmy hedgehog. Chromosome analysis by C-banding/DAPI showed large segments of heterochromatin rich in A-T pairs on three autosome pairs in both the northern white-breasted and African pygmy hedgehogs. The heterochromatin segments encompassed large fragments of the longer arm of chromosome pairs 13, 14 and 20. The (TTAGGG)ₙ repeat sequences on the hedgehog chromosomes were only observed in the terminal position of all the chromosomes in both species. Our observations provide new information on the level of diversity within the Erinaceidae family.
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