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Cryptosporidium immunolabeling in paraffinembedded ileum of CD-1 neonatal mice Texte intégral
2018
Mammeri, Mohamed | Huet, Hélène | Julien, Christine | Vallée, Isabelle | Cordonnier, Nathalie | Adjou, Karim, Tarik | Biologie moléculaire et immunologie parasitaires et fongiques (BIPAR) ; École nationale vétérinaire d'Alfort (ENVA)-Laboratoire de santé animale, sites de Maisons-Alfort et de Normandie ; Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES)-Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | École nationale vétérinaire d'Alfort (ENVA) | Phileo by Lesaffre
International audience
Afficher plus [+] Moins [-]Genotypic characterisation of Avian paramyxovirus type-1 viruses isolated from aquatic birds in Uganda. Texte intégral
2018
Wanyana, Agnes | Mugimba, Kizito K | Bosco, Omony J | Kirunda, Halid | Nakavuma, Jessica L | Teillaud, Angelique, A. | Ducatez, Mariette | Byarugaba, Denis K | Makerere University [Kampala, Ouganda] (MAK) | Interactions hôtes-agents pathogènes [Toulouse] (IHAP) ; Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)
International audience | Avian paramyxovirus type-1 (APMV-1) viruses of the lentogenic pathotypes are often isolated from wild aquatic birds and may mutate to high pathogenicity when they cross into poultry and cause debilitating Newcastle disease. This study characterised AMPV-1 isolated from fresh faecal droppings from wild aquatic birds roosting sites in Uganda. Fresh faecal samples from wild aquatic birds at several waterbodies in Uganda were collected and inoculated into 9-10-day-old embryonated chicken eggs. After isolation, the viruses were confirmed as APMV-1 by APMV-1-specific polymerase chain reaction (PCR). The cleavage site of the fusion protein gene for 24 representative isolates was sequenced and phylogenetically analysed and compared with representative isolates of the different APMV-1 genotypes in the GenBank database. In total, 711 samples were collected from different regions in the country from which 72 isolates were recovered, giving a prevalence of 10.1%. Sequence analysis of 24 isolates revealed that the isolates were all lentogenic, with the typical 111GGRQGR'L117 avirulent motif. Twenty-two isolates had similar amino acid sequences at the cleavage site, which were different from the LaSota vaccine strain by a silent nucleotide substitution T357C. Two isolates, NDV/waterfowl/Uganda/MU150/2011 and NDV/waterfowl/Uganda/MU186/2011, were different from the rest of the isolates in a single amino acid, with aspartate and alanine at positions 124 and 129, respectively. The results of this study revealed that Ugandan aquatic birds indeed harbour APMV-1 that clustered with class II genotype II strains and had limited genetic diversity.
Afficher plus [+] Moins [-]Zootechnical performance of Girolando cattle at Kpinnou Breeding Farm, South-West of Benin Republic Texte intégral
2018
Alassane, Yacoubou | Ahounou, Serge Gbênagnon | Toleba, Soumanou Seibou | Adjakpa, Achille Amour | Dotche, Ignace Ogoudanan | Houaga, Isidore | Moula, Nassim | Antoine-Moussiaux, Nicolas | Hornick, Jean-Luc | Youssao, Abdou Karim Issaka
peer reviewed | Objective: The aim of the study was to assess the weight and reproductive performances of Girolando cattle at Kpinnou Breeding Farm (KBF) in the south western of Benin Republic. Materials and methods: The weight performance and body measurements were taken on a total of 150 Girolando cattle. The study of the reproductive traits was based on the recorded demographic indicators between 2012-2013 of 67 cows. Results: From calving to the age of 3 months, the monthly average weight of calves did not vary with the season of calving (P>0.05). Between the 4th and 9th month, the weight varied with the birth seasons and the sex of the calf. Beyond 9th month, the calf’s average weight was the same regardless the calving season. At the age of 24 months, the highest weight (393.33 kg) was obtained during the long rainy season. The highest average weight was 398.22 Kg for males against 364.25 Kg for females at 24 months. The fertility rates ranged from 91.18% to 100% and the fecundity rate ranged from 85.29% to 103% during the study period. The apparent fertility rate was 91.18%. As for the calving and abortion rates, they were 93.55% and 6.45%, respectively. The mortality rate before weaning was 6.90% while the weaning viability was 93.10%. Calving occurred from January to June and from August to December. Conclusion: In overall, the Girolando performances are satisfactory and show a good adaptation at KBF.
Afficher plus [+] Moins [-]New method of analysis of nitrofurans and nitrofuran metabolites in different biological matrices using UHPLC-MS/MS Texte intégral
2018
Śniegocki, Tomasz | Giergiel, Marta | Sell, Bartosz | Posyniak, Andrzej
The major difficulty in analysis of nitrofurans in feed, feed water, and food of animal origin is that nitrofurans have low molecular weights and fast metabolism. The principal goal of this study was to prepare a procedure for the determination of nitrofurans and their metabolites by a single method in different types of feed, feed water, and food of animal origin. Two-gram samples were subjected to hydrolysis and derivatisation processes by addition of hydrochloric acid and 2-nitrobenzaldehyde. After incubation the sample was purified by solid phase extraction technique. Nitrofurans were analysed using ultra-high-pressure liquid chromatography-MS/MS (UHPLC-MS/MS). The results of validation fulfil the requirement of the confirmatory criteria according to the European Commission Decision 2002/657/EC regarding apparent recoveries (88.9%–107.3%), repeatability (2.9%–9.4%) and within-laboratory reproducibility (4.4%–10.7%). The method can be successfully applied to monitor nitrofurans and their metabolites in different matrices.
Afficher plus [+] Moins [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method Texte intégral
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with 0.05 M sulphuric acid and purified with MCX cartridges. A solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine (8:1:1:0.1:0.1, v/v) was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC–MS analysis. The developed method was validated according to SANTE/11945/2015 requirements. The recovery was from 80.6% to 114.5%. The repeatability ranged from 2.3% to 14.6%, and the reproducibility was from 4.9% to 17.7%. A new method for the determination of PAs in honey has been developed and validated. All evaluated parameters were in accordance with the SANTE/11945/2015 guidance document. Out of 50 analysed honey samples, 16 (32%) were positive for the content of at least one PA.
Afficher plus [+] Moins [-]Treatment of selected canine dermatological conditions in Portugal – a research survey Texte intégral
2018
Oliveira, Ana | Devesa, Joana S.P. | Hill, Peter B. | Silva, Vanessa | Poeta, Patrícia
Introduction: Staphylococcus pseudintermedius and Malassezia pachydermatis often cause skin diseases in dogs. Material and Methods: An online survey was e-mailed to veterinary practices nationwide covering demographics, diagnosis methods, and oral and topical treatment options. Of the 740 surveys sent, 100 complete replies were obtained. Results: The majority of clinicians were unaware of the existence of the International Society for Companion Animal Infectious Diseases guidelines or did not follow them (53%). Oral antibiotics were used universally for superficial bacterial folliculitis treatment, particularly amoxicillin-clavulanic acid (100%), cephalexin (94%), enrofloxacin (67%), or marbofloxacin (60%). For fold dermatitis (FD) and otitis externa (OE), oral antibiotics were also given as treatment in 88% and 82% of cases, respectively. Oral antifungals were often prescribed for generalised Malassezia dermatitis (85%), FD (70%), and OE (59%). S. pseudintermedius and M. pachydermatis were frequently treated topically, particularly with antibacterials or antifungals only, or a combination of antibacterials, antifungals, and glucocorticoids. Alternative options such as honey-based products were not frequently used. Conclusion: Our survey suggests that oral antibiotics are overused by Portuguese clinicians despite the spread of antibiotic resistant S. pseudintermedius. Oral antibiotics and antifungals are commonly prescribed for skin conditions manageable with topical treatments.
Afficher plus [+] Moins [-]Effects of polymyxin B on clinical signs, serum TNF-α, haptoglobin and plasma lactate concentrations in experimental endotoxaemia in sheep Texte intégral
2018
Hajimohammadi, Ali | Badiei, Khalil | Kheibari, Parviz | Pourjafar, Meherdad | Chalmeh, Aliasghar
The experiment evaluated the effects of intravenous administration of polymyxin B on experimental endotoxaemia in sheep. Twenty clinically healthy fat-tailed sheep were randomly divided into: a group treated with 6,000 U/kg of polymyxin B, a group at 12,000 U/kg, and positive and negative controls. Endotoxaemia was induced by intravenous administration of lipopolysaccharide (LPS) from E. coli serotype O55:B5 at 0.5 μg/kg. polymyxin was infused intravenously along with 2.5 L of isotonic intravenous fluids at 20 mL/kg/h. The positive control group received LPS and 2.5 L of isotonic fluids, the negatives receiving just 2.5 L of isotonic fluids. Clinical signs were evaluated before and at 1.5, 3, 4.5, 6, 24, and 48 h after LPS administration. Blood was also sampled at the denoted hours and serum haptoglobin, tumour necrosis factor-α (TNF-α), and plasma lactate concentrations were assayed. The serum concentration of TNF-α in the positive control group increased significantly up to 48 h after LPS administration. The concentration of TNF-α was significantly different from those of the polymyxin B and positive control groups from 3 to 48 h; also, the concentrations of haptoglobin at different times in the polymyxin groups were lower than those of the positive control group and were significant at hours 3 to 48 (P < 0.05). Following the LPS administration, haptoglobin and TNF-α concentrations changed without significant difference between the two polymyxin B groups. Polymyxin B (6,000 U/kg) restrained blood lactate concentrations. Furthermore, it significantly improved the clinical signs in endotoxaemic animals, including rectal temperature and heart and respiratory rates. Polymyxin B may be an antiendotoxic in fat-tailed sheep.
Afficher plus [+] Moins [-]Use of a new LC-MS method for the determination of pyrrolizidine alkaloids in feeds Texte intégral
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by many plant species. Due to their toxicity PAs can pose a risk to human and animal health. To detect the toxic compounds in feed materials a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with sulphuric acid and purified with cation exchange cartridges. A newly developed solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC-MS analysis. The developed method was validated according to SANTE/11945/2015 guidelines. The recovery was from 84.1% to 112.9%, the repeatability ranged from 3.0% to 13.6%, and the reproducibility was from 4.8% to 18.9%. A sensitive and selective method for determination of PAs in feed materials has been developed and validated. All evaluated validation parameters were in accordance with EU Reference Laboratories document no. SANTE/11945/2015. Almost 41% of the analysed feed samples were positive for the presence of at least one PA.
Afficher plus [+] Moins [-]Development of a new RT-PCR with multiple primers for detecting Southern African Territories foot-and-mouth disease viruses Texte intégral
2018
Liu, Yali | Ding, Yao-Zhong | Dai, Jun-Fei | Ma, Bing | He, Ji-Jun | Ma, Wei-Min | Lv, Jian-Liang | Ma, Xiao-Yuan | Ou, Yun-Wen | Wang, Jun | Liu, Yong-Sheng | Chang, Hui-Yun | Wang, Yong-Lu | Zhang, Qiang | Liu, Xiang-Tao | Zhang, Yong-Guang | Zhang, Jie
Introduction: The extremely high genetic variation and the continuously emerging variants of foot-and-mouth disease virus (FMDV) of Southern African Territory (SAT) serotypes including SAT1, SAT2, and SAT3 make it necessary to develop a new RT-PCR for general use for monitoring viruses based on the updated genome information. Material and Methods: A FMDV SAT-D8 one-step RT-PCR was established based on the 1D2A2B genes of the SAT serotype viruses with a multiplex primer set. FMDV A, O, C, and Asia 1 serotypes, other vesicular disease viruses, inactivated SAT viruses, and 125 bovine, ovine, caprine and porcine tissue samples collected from the Chinese mainland were included for evaluating the assay. Results: The new RT-PCR was proven to be specific without cross-reactions with Eurasian FMDV, swine vesicular disease virus (SVDV), Seneca valley virus (SVV), or other common viral pathogens of cattle, sheep, goat, and pig. An around 257 bp-sized amplicon clearly appeared when the inactivated SAT viruses were detected. However, all 125 samples collected from FMDV-susceptible animals from the Chinese mainland which has not known SAT epidemics showed negative results. Conclusions: A FMDV SAT-D8 one-step RT-PCR is a promising method for primary screening for FMDV SAT serotypes.
Afficher plus [+] Moins [-]Immune-enhancing activity of potential probiotic strains of Lactobacillus plantarum in the common carp (Cyprinus carpio) fingerling Texte intégral
2018
Kazuń, Barbara | Małaczewska, Joanna | Kazuń, Krzysztof | Żylińska-Urban, Joanna | Siwicki, Andrzej K.
Introduction: Immune-potentiating functions of Lactobacillus plantarum strains in the common carp were evaluated. Material and Methods: Fourteen days of feeding fish dry diet supplemented with the bacteria provided parameters of nonspecific humoral immunity (lysozyme, ceruloplasmin, γ-globulin, total protein levels, and serum bactericidal activity) and cellular immunity (pinocytosis, respiratory burst activity, and potential killing activity of organ phagocytes), as well as the proliferative response of organ lymphocytes stimulated with mitogens. The resistance of fish to infection with Aeromonas hydrophila was also determined. Results: Dietary supplementation with L. plantarum had a substantial influence on the activity of organ phagocytes, especially the potential killing activity of head kidney cells. A significant increase in the proliferative activity of LPS-stimulated B lymphocytes and in the levels of γ-globulins and total protein was observed. The supplemented diet conveyed higher resistance than the control diet as the cumulative fish mortalities after infection with A. hydrophila were 65% and 85%, respectively. Conclusion: The results indicate that dietary supplementation with L. plantarum stimulates the antibacterial resistance of common carp and may reinforce defence against bacterial infections, but further studies need to be conducted.
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