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41.
Virulence-associated trimeric autotransporters of Haemophilus parasuis are antigenic proteins expressed in vivo 总被引:1,自引:0,他引:1
Alex Olvera Sonia Pina Marta P��rez-Sim�� Simone Oliveira Albert Bensaid 《Veterinary research》2010,41(3)
Glässer’s disease is a re-emerging swine disease characterized by a severe septicaemia. Vaccination has been widely used to control the disease, although there is a lack of extended cross-protection. Trimeric autotransporters, a family of surface exposed proteins implicated in host-pathogen interactions, are good vaccine candidates. Members of this family have been described in Haemophilus parasuis and designated as virulence-associated trimeric autotransporters (VtaA). In this work, we produced 15 recombinant VtaA passenger domains and looked for the presence of antibodies directed against them in immune sera by immunoblotting. After infection with a subclinical dose of H. parasuis Nagasaki, an IgG mediated antibody response against 6 (VtaA1, 5, 6, 8, 9 and 10) of the 13 VtaA of the Nagasaki strain was detected, indicating that they are expressed in vivo. IgA production against VtaA was detected in only one animal. VtaA were more likely to be late antigens when compared to early (Omp P5 and Omp P6) and late (YaeT) defined antigens. Antibody cross-reaction with two orthologs of Nagasaki’s VtaA5 and 6, VtaA15 and 16 of strain HP1319, was also detected. No antibodies against VtaA were detected in the sera of animals immunized with a bacterin of the Nagasaki strain, suggesting poor expression in the in vitro conditions used. Taken together, these results indicate that VtaA are good candidate immunogens that could be used to improve H. parasuis vaccines. However, their capacity to confer protective immunity needs to be further studied. 相似文献
42.
Kagira JM Kanyari PN Githigia SM Maingi N Ng'ang'a JC Gachohi JM 《Tropical animal health and production》2012,44(3):657-664
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This
study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from
135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique.
The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also
administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode
eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free
range pigs in Busia District, which can be used when implementing integrated control measures. 相似文献
43.
Fayos M Couto CG Iazbik MC Wellman ML 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):397-400
BACKGROUND: Retired racing Greyhounds are becoming common as pets. Because of their unique physiology, results of routine laboratory tests are frequently outside the reference interval for dogs. Compared with other breeds, Greyhounds have low serum protein concentrations, but the concentrations of different serum protein fractions have not been reported. OBJECTIVES: Our objectives were to evaluate the results of serum protein electrophoresis (SPE) in healthy, retired racing Greyhounds and compare them with a control group of age- and gender-matched non-Greyhound dogs. METHODS: Agarose gel electrophoresis was done using a standard method; the gels were stained with amido black and scanned with a Cliniscan 2 densitometer (Helena Laboratories, Beaumont, TX, USA). Protein fractions were identified by visual inspection of the electrophoretogram. A Student's t-test assuming equal variances was used to compare the concentration of the different fractions between groups. RESULTS: The concentrations of total protein, total globulins, and alpha-1-, alpha-2-, beta-1-, and beta-2-globulins were significantly lower and the albumin to globulin (A:G) ratio was significantly higher in Greyhounds than in non-Greyhound dogs (P < .05). There was no significant difference in albumin or gamma-globulin concentrations. CONCLUSIONS: Low serum protein concentrations in Greyhounds are the result of low concentrations of a- and b-globulins. These results should be kept in mind when evaluating both healthy and sick Greyhounds. Additional studies are needed to identify the individual proteins associated with low alpha- and beta-globulin concentrations in Greyhounds. 相似文献
44.
Sophie Blani�� J��r��my Mortier Maxence Delverdier St��phane Bertagnoli Christelle Camus-Bouclainville 《Veterinary research》2009,40(1)
Myxoma virus (MYXV), a member of the Poxviridae family, is the agent responsible for myxomatosis, a fatal disease in the European rabbit (Oryctolagus cuniculus). MYXV has a linear double-stranded DNA genome that encodes several factors important for evasion from the host immune system. Among them, four ankyrin (ANK) repeat proteins were identified: M148R, M149R, M150R and M-T5. To date, only M150R and M-T5 were studied and characterized as critical virulence factors. This article presents the first characterization of M148R and M149R. Green Fluorescent Protein (GFP) fusions allowed us to localize them in a viral context. Whereas M149R is only cytoplasmic, interestingly, M148R is in part located in the nucleolus, a unique feature for an ANK repeat poxviral protein. In order to evaluate their implication in viral pathogenicity, targeted M148R, M149R, or both deletions were constructed in the wild type T1 strain of myxoma virus. In vitro infection of rabbit and primate cultured cells as well as primary rabbit cells allowed us to conclude that M148R and M149R are not likely to be implicated in cell tropism or host range functions. However, in vivo experiments revealed that they are virulence factors since after infection of European rabbits with mutant viruses, a delay in the onset of clinical signs, an increase of survival time and a dramatic decrease in mortality rate were observed. Moreover, histological analysis suggests that M148R plays a role in the subversion of host inflammatory response by MYXV. 相似文献
45.
Hernández Juan Augusto Lepe Marissa Macedo Rafael Arredondo Victalina Cortez Carlos Eliseo García Luis Jorge Prado Omar 《Tropical animal health and production》2017,49(1):173-178
Tropical Animal Health and Production - A study was conducted with the objective to characterize the morphology of Socorro Island Merino sheep. A total of 67 sheep, 62 females, 26 purebred and 36... 相似文献
46.
M. Belén García-Rodríguez M. Angeles Ríos Granja C. César Pérez García Jose M. Gonzalo Orden Maria J. Cano Rábano Inmaculada Diez Prieto 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(9):933-935
This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of the ASD was measured by magnetic resonance imaging (MRI). 相似文献
47.
Donna M. White José I. Redondo Alastair R. Mair Fernando Martinez-Taboada 《Veterinary anaesthesia and analgesia》2017,44(5):1076-1084
Objective
The effect of user experience and inflation technique on endotracheal tube cuff pressure using a feline airway simulator.Study design
Prospective, experimental clinical study.Methods
Participants included veterinary students at the beginning (group S1) and end (group S2) of their 2-week anaesthesia rotation and veterinary anaesthetists (group A). The feline airway simulator was designed to simulate an average size feline trachea, intubated with a 4.5 mm low-pressure, high-volume cuffed endotracheal tube, connected to a Bain breathing system with oxygen flow of 2 L minute?1. Participants inflated the on-endotracheal tube cuff by pilot balloon palpation and by instilling the minimum occlusive volume (MOV) required for loss of airway leaks during manual ventilation. Intracuff pressures were measured by manometers obscured to participants and ideally were 20–30 cm H2O. Student t, Fisher exact, and Chi-squared tests were used where appropriate to analyse data (p < 0.05).Results
Participants were 12 students and eight anaesthetists. Measured intracuff pressures for palpation and MOV, respectively, were 19 ± 12 and 29 ± 19 cm H2O for group S1, 10 ± 5 and 20 ± 11 cm H2O for group S2 and 13 ± 6 and 29 ± 18 cm H2O for group A. All groups performed poorly at achieving intracuff pressures within the ideal range. There was no significant difference in intracuff pressures between techniques. Students administered lower (p = 0.02) intracuff pressures using palpation after their training.Conclusions and clinical relevance
When using palpation and MOV for cuff inflation operators rarely achieved optimal intracuff pressures. Experience had no effect on this skill and, as such, a cuff manometer is recommended. 相似文献48.
Gerardo Ordaz-Ochoa Aureliano Juárez-Caratachea Rosa Elena Pérez-Sánchez Rafael María Román-Bravo Ruy Ortiz-Rodríguez 《Tropical animal health and production》2017,49(5):1025-1033
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI. 相似文献
49.
50.
María Sol Arias Jos Luis Surez G.V. Hillyer Ivn Francisco Enrique Calvo Rita Snchez-Andrade Pablo Díaz Rubn Francisco Pablo Díez-Baos Patrocinio Morrondo Adolfo Paz-Silva 《Veterinary journal (London, England : 1997)》2009,182(1):73-78
The therapeutic efficacy of albendazole and netobimin in ruminants with naturally occurring fascioliasis was investigated using a recombinant-based ELISA. The variation in the IgG response against a 2.9-kDa recombinant protein (FhrAPS), termed efficacy index (EI) 1, and the egg-output changes, termed EI 2, were used to evaluate drug efficacy.The values of EI 1 ranged between 0% and 50% in sheep, and between 0% and 30% in cattle after treatment with albendazole and netobimin. Similar EI 2 values were observed in sheep receiving albendazole or netobimin, but the highest values were found in cattle treated with netobimin. The significant reduction in the IgG response to FhrAPS found in this study shows promise in terms of developing alternative methods for evaluating the efficacy of chemotherapy against Fasciola hepatica in grazing ruminants. 相似文献