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Phylogenetic study of H5 low pathogenic avian influenza viruses detected in wild birds in Poland in 2010−2015
2017
Świętoń, Edyta | Śmietanka, Krzysztof
Introduction: The genomes of nine H5 subtypes of low pathogenic avian influenza virus (LPAIV) strains identified in wild birds in Poland between 2010 and 2015 were sequenced, and their phylogenetic relationship was determined. Material and Methods: AIV genome segments were amplified by RT-PCR and the PCR products were sequenced using Sanger method. Phylogenetic trees were generated in MEGA6 software and digital genotyping approach was used to visualise the relationship between analysed strains and other AIVs. Results: High genetic diversity was found in the analysed strains as multiple subgroups were identified in phylogenetic trees. In the HA tree, Polish strains clustered in two distinct subclades. High diversity was found for PB2, PB1, PA and NP, since 5-8 sublineages could be distinguished. Each strain had a different gene constellation, although relationship of as much as six out of eight gene segments was observed between two isolates. A relationship with poultry isolates was found for at least one segment of each Polish strain. Conclusion: The genome configuration of tested strains indicates extensive reassortment, although the preference for specific gene constellation could be noticed. A significant relationship with isolates of poultry origin underlines the need for constant monitoring of the AIV gene pool circulating in the natural reservoir.
Afficher plus [+] Moins [-]Serological survey of the influenza A virus in Polish farrow-to-finish pig herds in 2011–2015
2017
Czyżewska-Dors, Ewelina | Dors, Arkadiusz | Kwit, Krzysztof | Pejsak, Zygmunt | Pomorska-Mól, Małgorzata
Introduction: The aim of this study was to assess the seroprevalence of swine influenza A virus (SIV) in Polish farrow-to-finish pig herds.Material and Methods: Serum samples collected from 5,952 pigs, from 145 farrow-to-finish herds were tested for the presence of antibodies against H1N1, H1N1pdm09, H1N2, and H3N2 SIV subtypes using haemagglutination inhibition (HI) test. Samples with HI titres equal or higher than 20 were considered positive.Results: HI antibodies to at least one of the analysed SIV subtypes were detected in 129 (89%) herds and in 2,263 (38%) serum samples. Antibodies to multiple SIV subtypes were detected in 104 (71.7%) herds and in 996 (16.7%) serum samples. Concerning the seroprevalence rate, according to age category, the highest prevalence of the antibodies was detected in weaners, with regard to the H1N1, H1N2, and H3N2, and in sows, with regard to the H1N1pdm09. The lowest seroprevalence for all evaluated SIV subtypes was detected in finishers.Conclusion: The study indicates that antibodies against single and multiple SIV subtypes are circulating in Polish farrow-to-finish herds and highlights the importance of conducting a molecular surveillance programme in future studies.
Afficher plus [+] Moins [-]Identification of infectious bursal disease virus with atypical VP2 amino acid profile in Latvia
2017
Introduction: Infectious bursal disease virus (IBDV) is a causative agent of immunosuppressive disorder resulting in significant losses to the world poultry industry. This study describes the molecular characterisation of an atypical IBDV from a field outbreak that occurred in vaccinated chicken flocks in Latvia in 2011.Material and Methods: Ten bursae of Fabricius from each flock were collected for laboratory examination. Virus isolation was performed in embryonated eggs and CEF culture. The RT-PCR aimed at hypervariable domain of VP2 gene combined with sequencing was performed for detection and identification of IBDV.Results: The molecular examinations confirmed the IBDV infection. The analysis of the amino acid sequence revealed that the strain possessed four amino acids at VP2 protein (222A, 256I, 294I, and 299S), indicating a genetic relatedness to a very virulent IBDV. However, some unique or rare amino acid substitutions (219L, 220F, 254D, 279N, and 280T) were also detected.Conclusion: The obtained results demonstrate the occurrence of IBDV with a high mutation rate within the hypervariable domain of VP2 peptide, and highlight the necessity of implementation of IBDV surveillance in Eastern European poultry industry to determine whether this strain is an exception or a new wave of IBDV with new genetic features emerged in the field.
Afficher plus [+] Moins [-]Detection of Actinobacillus pleuropneumoniae ApxIV toxin antibody in serum and oral fluid specimens from pigs inoculated under experimental conditions
2017
González, Wendy | Giménez-Lirola, Luis G. | Holmes, Ashley | Lizano, Sergio | Goodell, Christa | Poonsuk, Korakrit | Sitthicharoenchai, Panchan | Sun, Yaxuan | Zimmerman, Jeffrey
Introduction: The prevention and control of Actinobacillus pleuropneumoniae in commercial production settings is based on serological monitoring. Enzyme-linked immunosorbent assays (ELISAs) have been developed to detect specific antibodies against a variety of A. pleuropneumoniae antigens, including long-chain lipopolysaccharides (LPS) and the ApxIV toxin, a repeats-in-toxin (RTX) exotoxin unique to A. pleuropneumoniae and produced by all serovars. The objective of this study was to describe ApxIV antibody responses in serum and oral fluid of pigs.Material and Methods: Four groups of pigs (six pigs per group) were inoculated with A. pleuropneumoniae serovars 1, 5, 7, or 12. Weekly serum samples and daily oral fluid samples were collected from individual pigs for 56 days post inoculation (DPI) and tested by LPS and ApxIV ELISAs. The ApxIV ELISA was run in three formats to detect immunlgobulins M, G, and A (IgM, IgG and IgA) while the LPS ELISA detected only IgG.Results: All pigs inoculated with A. pleuropneumoniae serovars 1 and 7 were LPS ELISA serum antibody positive from DPI 14 to 56. A transient and weak LPS ELISA antibody response was observed in pigs inoculated with serovar 5 and a single antibody positive pig was observed in serovar 12 at ≥35 DPI. Notably, ApxIV serum and oral fluid antibody responses in pig inoculated with serovars 1 and 7 reflected the patterns observed for LPS antibody, albeit with a 14 to 21 day delay.Conclusion: This work suggests that ELISAs based on ApxIV antibody detection in oral fluid samples could be effective in population monitoring for A. pleuropneumoniae.
Afficher plus [+] Moins [-]Maternal and fetal arterial blood gas data in normotensive, singleton, isoflurane anesthetized sheep at 124-126 days of gestation
2017
Loughran, C. M. | Kemp, M. W. | Musk, G. C.
The aim of this case series was to describe the differences between maternal and fetal blood-gas results during anesthesia. Sixteen singleton adult merino ewes weighing 60.1 ± 5.1 kg at 125.7 d (124 to 126 d) gestation were anesthetized. Maternal (radial) and fetal (umbilical) arterial blood gas samples were collected 79 ± 6 min after the start of anesthesia if maternal mean arterial pressure (MAP) was stable and > 65 mmHg. Fetal pH, partial arterial pressure of oxygen (PaO2), glucose, arterial hemoglobin oxygen saturation (SaO2), sodium, and chloride were significantly lower and fetal partial arterial pressure of carbon dioxide (PaCO2), lactate, hematocrit, total hemoglobin, potassium, and calcium were significantly higher than maternal blood-gas values. Fetal pH, PaO2, and BE were lower and fetal lactate was higher than fetal umbilical arterial samples previously reported, which may indicate a non-reassuring fetal status. Further refinement of the ovine experimental model is warranted with fetal monitoring during maternal anesthesia.
Afficher plus [+] Moins [-]Evaluation of pathogen-specific biomarkers for the diagnosis of tuberculosis in white-tailed deer (Odocoileus virginianus)
2017
Wanzala, Sylvia I. | Palmer, Mitchell V. | Waters, Wade R. | Thacker, Tyler C. | Carstensen, Michelle | Travis, Dominic A. | Sreevatsan, Srinard
OBJECTIVE To develop a noninvasive biomarker-based detection system specific for Mycobacterium bovis for monitoring infection in wild animals. SAMPLE Serum samples from 8 experimentally infected yearling white-tailed deer (Odocoileus virginianus) and 3 age-matched control deer and from 393 Minnesota Department of Natural Resources hunter-harvested white-tailed deer in northwest Minnesota. PROCEDURES 8 yearling deer were inoculated with 2 × 10(8) CFUs of virulent M bovis strain 1315 (day 0), and sera were obtained on days 0, 19, 48, and 60; sera were obtained from 3 uninoculated control deer on those same days. Sera from these deer and 9 M bovis-positive hunter-harvested deer were tested for 3 Mycobacterium-specific biomarkers (MB1895c, MB2515c, and polyketide synthase 5) by use of an indirect ELISA. That same ELISA was used to test sera obtained from 384 exposed noninfected deer in northwest Minnesota from 2007 through 2010, concurrent with an outbreak of tuberculosis involving cattle and deer in that region. RESULTS ELISA results revealed that tuberculosis infection could be detected as early as 48 days after inoculation in experimentally infected deer. Results for 384 deer sera revealed that prevalence of tuberculosis decreased over the 4-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the prevalence of tuberculosis in Minnesota deer decreased after 2009 but tuberculosis may have persisted (as subclinical disease) at extremely low levels, as indicated by the presence of low concentrations of circulating biomarkers. Biomarker-based diagnostic tests may offer a specific approach for early identification of M bovis infection.
Afficher plus [+] Moins [-]Evaluation of infrared thermography as a diagnostic tool to predict heat stress events in feedlot cattle
2017
Unruh, Ellen M. | Theurer, Miles E. | White, Brad J. | Larson, Robert L. | Drouillard, James S. | Schrag, Nora
OBJECTIVE To determine whether infrared thermographic images obtained the morning after overnight heat abatement could be used as the basis for diagnostic algorithms to predict subsequent heat stress events in feedlot cattle exposed to high ambient temperatures. ANIMALS 60 crossbred beef heifers (mean ± SD body weight, 385.8 ± 20.3 kg). PROCEDURES Calves were housed in groups of 20 in 3 pens without any shade. During the 6 am and 3 pm hours on each of 10 days during a 14-day period when the daily ambient temperature was forecasted to be > 29.4°C, an investigator walked outside each pen and obtained profile digital thermal images of and assigned panting scores to calves near the periphery of the pen. Relationships between infrared thermographic data and panting scores were evaluated with artificial learning models. RESULTS Afternoon panting score was positively associated with morning but not afternoon thermographic data (body surface temperature). Evaluation of multiple artificial learning models indicated that morning body surface temperature was not an accurate predictor of an afternoon heat stress event, and thermographic data were of little predictive benefit, compared with morning and forecasted weather conditions. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated infrared thermography was an objective method to monitor beef calves for heat stress in research settings. However, thermographic data obtained in the morning did not accurately predict which calves would develop heat stress later in the day. The use of infrared thermography as a diagnostic tool for monitoring heat stress in feedlot cattle requires further investigation.
Afficher plus [+] Moins [-]Evaluation of a telemetric gastrointestinal pill for continuous monitoring of gastrointestinal temperature in horses at rest and during exercise
2017
Verdegaal, Elisabeth-Lidwien J. M. M. | Delesalle, Catherine | Caraguel, Charles G. B. | Folwell, Louise E. | McWhorter, Todd J. | Howarth, Gordon S. | Franklin, Samantha H.
OBJECTIVE To evaluate use of a telemetric gastrointestinal (GI) pill to continuously monitor GI temperature in horses at rest and during exercise and to compare time profiles of GI temperature and rectal temperature. ANIMALS 8 Standardbred horses. PROCEDURES Accuracy and precision of the GI pill and a rectal probe were determined in vitro by comparing temperature measurements with values obtained by a certified resistance temperature detector (RTD) in water baths at various temperatures (37°, 39°, and 41°C). Subsequently, both GI and rectal temperature were recorded in vivo in 8 horses over 3 consecutive days. The GI temperature was recorded continuously, and rectal temperature was recorded for 3.5 hours daily. Comparisons were made between GI temperature and rectal temperature for horses at rest, during exercise, and after exercise. RESULTS Water bath evaluation revealed good agreement between the rectal probe and RTD. However, the GI pill systematically underestimated temperature by 0.14°C. In vivo, GI temperature data were captured with minimal difficulties. Most data loss occurred during the first 16 hours, after which the mean ± SD data loss was 8.6 ± 3.7%. The GI temperature was consistently and significantly higher than rectal temperature with an overall mean temperature difference across time of 0.27°C (range, 0.22° to 0.32°C). Mean measurement cessation point for the GI pill was 5.1 ± 1.0 days after administration. CONCLUSIONS AND CLINICAL RELEVANCE This study revealed that the telemetric GI pill was a reliable and practical method for real-time monitoring of GI temperature in horses.
Afficher plus [+] Moins [-]Evaluation of gastroscopy and biopsy of the proventriculus and ventriculus in pigeons (Columba livia)
2017
Sladakovic, Izidora | Ellis, Angela E. | Divers, Stephen J.
OBJECTIVE To evaluate the efficacy and safety of gastroscopy and biopsy of the proventriculus and ventriculus in pigeons (Columba livia). ANIMALS 15 adult pigeons. PROCEDURES Each pigeon was anesthetized, and the upper gastrointestinal tract (from the cervical portion of the esophagus to the ventriculus) was endoscopically evaluated by use of a rigid endoscope inserted orally. Saline (0.9% NaCl) solution was orally infused to achieve lumen dilation and visibility. Two mucosal biopsy specimens were collected from each of the proventriculus and ventriculus, histologically evaluated, and graded for crush artifacts and depth. Pigeons were monitored for adverse effects for 3 to 6 days after the procedure, after which they were euthanized for necropsy. RESULTS Gastroscopy via the oral approach provided excellent visibility of the lumen and mucosal surfaces of the proventriculus and cranial portion of the ventriculus and was safe provided that appropriate precautions were taken. Two intraoperative deaths occurred at the beginning of the study; following procedure refinement, no additional deaths occurred. No major adverse effects of the procedure were detected in the remaining 13 pigeons during the postoperative monitoring period or at necropsy. Diagnostic quality of proventriculus specimens was adequate for 10 of 13 pigeons. Eight of 13 ventriculus specimens were of inadequate quality, and only 3 were of adequate quality. CONCLUSIONS AND CLINICAL RELEVANCE Gastroscopy was useful for evaluating the lumen and mucosal surface of the proventriculus and ventriculus in pigeons, and biopsy of those organs was safely performed with the appropriate technique. Further evaluation of these techniques is needed in birds with clinical disease and birds of other species.
Afficher plus [+] Moins [-]Pharmacokinetics of terbinafine in little brown myotis (Myotis lucifugus) infected with Pseudogymnoascus destructans
2017
Court, Michael H. | Robbins, Alison H. | Whitford, Anne M. | Beck, Erika V. | Tseng, Flo S. | Reeder, DeeAnn M.
OBJECTIVE To determine the pharmacokinetics of terbinafine in little brown myotis (Myotis lucifugus) infected with Pseudogymnoascus destructans. ANIMALS 123 bats from a P destructans–infected hibernation site in Virginia. PROCEDURES 3 bats were euthanized and necropsied to confirm the presence of P destructans within the population. The remaining 120 bats were systematically assigned to 6 groups (20 bats/group). Bats in each of 3 groups received 6, 20, or 60 mg of terbinafine/kg, SC, once daily for 10 days. Bats in another group received 200 mg of terbinafine/kg, SC, once daily for 5 days. Bats in 1 group received the terbinafine vehicle solution (0.1 mL/kg, SC, once daily for 10 days). Bats in the remaining group did not receive any treatment. Following the treatment period (days 1 through 10), bats were housed in a hibernation chamber and monitored daily until euthanasia on day 42, 75, or 109. Tissue specimens were collected from all bats as soon as possible after death or euthanasia to determine terbinafine concentration. Within each group and tissue type, terbinafine concentration data were pooled, and pharmacokinetic parameters were calculated by noncompartmental methods. RESULTS Adverse neurologic effects and a high mortality rate before day 10 were observed in bats that received the highest terbinafine dose (200 mg/kg) but not those that received lower doses. Presumed therapeutic terbinafine concentrations (≥ 2 μg/g) were maintained in skin and wing for at least 30 and 6 days in bats that received the 60 and 20 mg/kg doses, respectively, but were not achieved in most bats that received the 6 mg/kg dose. Tissue terminal half-life ranged from 14 to 22 days. Terbinafine concentration in hair was positively correlated with that in skin and wing. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated terbinafine doses > 6 but < 200 mg/kg should be further evaluated for the treatment of P destructans–infected bats. Collection of serial hair specimens may represent a noninvasive method for monitoring terbinafine concentration in treated bats.
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