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Potential role of different fish species as vectors of koi herpesvirus (CyHV-3) infection
2019
Matras, Marek | Stachnik, Magdalena | Borzym, Ewa | Maj-Paluch, Joanna | Reichert, Michał
Koi herpesvirus (KHV) has infected farmed common carp in Poland clinically and asymptomatically since 2004. The role of non-carp species as vectors of virus transmission is well known except for in the case of KHV. The aim was to better understand this virus’ infection and transmission pathways in common carp, looking at the potential vector role of fishes kept with them. Eight species were experimentally infected with KHV by immersion in a suspension at 20°C ±1 and transferred to a tank after 45 minutes. Specimens were euthanised at intervals up to 56 days post infection (dpi) and tissue was examined for KHV DNA. Surviving infected fishes were introduced at intervals, each time into a separate tank, to naïve common carp for experimental infection. These were observed daily for symptoms, sacrificed along with controls after three months, and dissected to provide tissue samples. Also fish from 14 species collected from a farm with a history of KHV were sampled from 3 to 22 months after disease was confirmed. Organ sections from single fish were collected in a single tube. Viral DNA was detected in tench and roach samples up to 49 dpi, but in three-spined stickleback and stone maroko samples only up to 14 dpi. Transmission of KHV to naïve carp occurred after cohabitation. KHV DNA was detected in three fish species three months after the farm outbreak. We confirmed that grass and Prussian carp, tench, roach, and brown bullhead can transfer the virus to naïve common carp.
اظهر المزيد [+] اقل [-]Molecular detection and genetic diversity of porcine circovirus type 3 in commercial pig farms in Xinjiang province, China
2019
Mengfan, Qiao | Xifeng, Wang | Guowu, Zhang | Qingling, Meng | Jun, Qiao | Lixia, Wang | Kuojun, Cai | Jinsheng, Zhang | Zaichao, Zhang | Weiwei, Yu | Yelong, Peng | Xuepeng, Cai
Porcine circovirus type 3 (PCV3) is a newly discovered porcine circovirus. The molecular characteristics and genetic evolution of PCV3 in Xinjiang province, China still being unclear, the aim of the study was their elucidation. A total of 393 clinical samples were collected from pigs on commercial farms in nine different regions of Xinjiang and phylogenetic analysis based on full-length Cap genes was performed. The prevalence at farm level was 100%, while in all the tested samples it was 22.39%. Nine PCV3 strains were detected in Xinjiang province and they shared 98.9–99.3% nucleotide and 97.5–100.0% Cap gene amino acid sequence identities with other epidemic strains from China and abroad. Compared with other epidemic strains of PCV3, there were 26 base mutation sites in the Cap gene in the nine Xinjiang strains, resulting in the mutation of amino acids at positions 20, 24, 75, 77, 108, 111 and 206. Phylogenetic analysis showed that these strains can be divided into two different genetic groups, to the first of which five strains affiliated and divided between subgroups 1.1 and 1.2, and to the second of which the other four strains affiliated and similarly divided between subgroups 2.1 and 2.2. PCV3 circulates widely among commercial pig farms in Xinjiang province, China, and displays obvious genetic diversity. The results provide epidemiological information useful for the prevention and control of PCV3 infection in the pig industry.
اظهر المزيد [+] اقل [-]Effects of ketosis in dairy cows on blood biochemical parameters, milk yield and composition, and digestive capacity
2019
Yang, Wei | Zhang, Bingbing | Xu, Chuang | Zhang, Hongyou | Xia, Cheng
This study aimed to characterise the effects of ketosis on milk yield and composition and digestive capacity in transition dairy cows. Seven ketotic and seven healthy cows were housed in individual stalls for six days. Samples of plasma, milk, refused total mixed ration, and faeces were collected, and the blood biochemical parameters, milk yield and composition, dry matter intake, and faecal dry matter (FDM) production were determined. Compared with healthy cows, the ketotic cows had significantly higher concentrations of milk fat and citrate, but lower levels of milk protein and lactose. The cows exhibited a need for acid detergent fibre in forage and better digestion of neutral detergent fibre, starch, crude protein, and phosphorus than healthy cows, but more fat and gross energy were excreted in their faeces. Ketotic cows had higher energy-corrected milk yields and lower FDM than healthy cows. Lower feed intake coinciding with the requirement to maintain high milk production is considered to be the cause of ketosis in dairy cows. Ketotic cows exhibited lower dry matter fat digestion.
اظهر المزيد [+] اقل [-]Changes in the activity of ovine blood-derived macrophages stimulated with antimicrobial peptide extract (AMP) or platelet-rich plasma (PRP)
2019
Wessely-Szponder, Joanna | Szponder, Tomasz | Bobowiec, Ryszard | Michalska, Joanna
Introduction: Antimicrobial peptides (AMP) are a large group of innate immune effectors, which apart from antimicrobial activity show immunomodulative properties. Platelet-rich plasma (PRP) is a source of autologous growth factors and is used for stimulation of bone and soft tissue healing. The purpose of this study was to assess the influence of PRP and AMP extract on ovine monocyte-derived macrophage cultures. Material and Methods: The study was conducted on ovine macrophages (Mfs) previously stimulated with LPS or dexamethasone and then with preparations of PRP or AMP. Following activation of the Mfs their morphological and functional features were assessed. Results: The study revealed pro-inflammatory influence of both examined preparations on Mfs cultures on the basis of morphology, ROS generation and arginase activity. Both preparations enhanced the pro-inflammatory response of cultured Mfs. Conclusion: This activity may intensify the antimicrobial action of Mfs, however, in cases of excessive and prolonged inflammation the use of these preparations should be limited.
اظهر المزيد [+] اقل [-]Applicability of thyroxine measurements and ultrasound imaging in evaluations of thyroid function in turtles
2019
Pajdak-Czaus, Joanna | Terech-Majewska, Elżbieta | Będzłowicz, Dagmara | Mączyński, Martyn | Krystkiewicz, Wioletta | Łabuć, Sebastian | Platt-Samoraj, Aleksandra | Szweda, Wojciech
Introduction: The thyroid and parathyroid glands play a major role in maintaining physiological homeostasis in all vertebrates. Reptiles have plasma concentrations of thyroid hormones far lower than mammals. Low levels of these hormones in reptiles impede thyroid hormone detection with assays designed for the higher levels of mammals. The aim of this study was to explore teaming this with ultrasound imaging of the thyroid to appraise glandular function. Material and Methods: Thyroid function of four pond sliders was evaluated based on the results of T4 analyses and ultrasound. Results: The concentrations of T4 varied considerably between the examined animals from <9 nmol/L to >167.3 nmol/L. Ultrasound examination revealed uniform echogenicity and a smooth outline of the thyroid gland in all animals. Conclusion: Monitoring of thyroid function based on T4 and electrolyte concentrations is helpful in assessing the health and living conditions of reptiles, which is important in veterinary practice but problematic. Ultrasound examinations are useful in diagnosing changes in gland structure, such as tumours and goitres, and a combination of both methods supports comprehensive assessments of the anatomy and function of the thyroid gland.
اظهر المزيد [+] اقل [-]Prevalence and phylogenetic analysis of Mycoplasma synoviae strains isolated from Polish chicken layer flocks
2019
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka, Anna
Introduction: Mycoplasma synoviae (MS) is a chicken pathogen of major economic importance. Material and Methods: Between 2010 and 2016, 906 commercial layer chicken flocks in Poland were examined for MS, and the phylogenetic relationship among the strains was established. Regionally dispersed samples were collected and tested with the use of real-time PCR to detect the 16S–23S intergenic spacer region. Positive samples were also tested with LAMP and conventional PCR to detect the vlhA gene. Results: MS genetic material was detected in 265 (29%) of the tested flocks by real-time PCR, in 227 by the LAMP method and in 202 (22%) by conventional PCR. The by-year percentage of positive samples began at 34% in 2010, rose to 44% in 2012, and declined to 29% in 2016. A phylogenetic analysis of Polish M. synoviae strains using a partial sequence of the vlhA gene showed nine genotypes (A–I), the most frequently occurring being F and C. Pathogenic Polish MS field isolates (n = 27) collected from chickens with clinical signs of infection were grouped for their characteristic symptoms: respiratory for genotypes C, E, F, and I (n = 13), EAA and a drop in laying for genotypes F, E, and C (n = 12), and synovitis for genotype A (n = 2). Conclusion: These data showed the country’s isolate diversity. The high prevalence suggests the need to introduce appropriate control programmes. This is the first report of molecular epidemiological data on M. synoviae infection in layer chickens in Poland.
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]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.
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