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Discrimination of healthy versus sick steers by means of continuous remote monitoring of animal activity Full text
2015
Smith, Jacqueline L. | Vanzant, Eric S. | Carter, Craig N. | Jackson, Carney B.
OBJECTIVE To test a unique electronic ear tag designed to collect movement data to determine whether physical activity of sick steers differed from that of healthy steers. ANIMALS 206 steers. PROCEDURES Physical activity in 2 groups of steers during November and December of 2010 (101 steers; the tag of 1 steer failed, and thus that steer was removed from the study, which resulted in data for 100 steers) and 2011 (105 steers) was monitored with an electronic ear tag device with an on-board triple-axis accelerometer. The accelerometer recorded motion in all 3 axes in the form of counts per minute. A radio-frequency transmitter on the ear tag delivered serial packets of motion data to a local server. An algorithm was developed to analyze the activity data to determine whether this technique could be used to assess health status with high accuracy. RESULTS Steers that became sick had significantly fewer activity counts (approx 25% fewer), compared with the activity counts of steers that remained healthy the entire time. CONCLUSIONS AND CLINICAL RELEVANCE In this study, automated detection of health status in growing cattle was feasible through remote monitoring of animal activity. Early identification of sick animals should lead to improved health outcomes, increased marketability, and improved animal well-being and help to minimize the use of antimicrobials that could contribute to resistant bacteria.
Show more [+] Less [-]Effects of isoflurane on somatosensory-evoked potentials in calves: A pilot study Full text
2015
Truchetti, Geoffrey | Burns, Patrick | Nichols, Sylvain | Parent, Joane
Somatosensory evoked potentials (SSEP) are used to monitor sensory function and are often recorded under general anesthesia. The objective of the study was to evaluate the effects of isoflurane on SSEPs in calves as it has not been reported. Eight calves (mean age: 40 days), were included in the study. Calves were anesthetized with a randomized sequence of four different isoflurane partial pressures. Blood gas analysis was performed before each measurement. SSEP were induced by repeated stimulation of the common dorsal digital nerve III. SSEPs were recorded from the lumbo-sacral junction (s-SSEP) and the head (c-SSEP). Latency and inter-amplitude of each peak were measured. For s-SSEP: One negative (Nsp1) and two positive (Psp1 and Psp2) peaks were identified in all tracings except for two calves. There was a significant effect of isoflurane on the latency of Psp2 (P = 0.01). Inter-amplitude decreased significantly with PaO2, PaCO2 and temperature (P < 0.05). Psp2 latency decreased with PaO2 (P = 0.01). For c-SSEP: two positive (Pc1 and Pc2) and two negative (Nc1 and Nc2) peaks were identified. There were identifiable peaks for the analysis of Pc1 latencies only. There was a significant positive linear relation between end-tidal isoflurane partial pressure (ETiso) and Pc1 latency (P = 0.04). None of the co-variables had a significant effect on the latency of Pc1 (P > 0.1). Isoflurane has a major impact on the recording of c-SSEP. Recording should be done at the lowest ETiso as possible, and anesthesia parameters should be kept constant.
Show more [+] Less [-]Flow cytometric evaluation of disseminated intravascular coagulation in a canine endotoxemia model Full text
2015
Yu, Dohyeon | Noh, Dongho | Park, Jinho
Sepsis is associated with substantial morbidity and mortality in dogs. Alterations in hemostasis by systemic inflammation play an important role in the pathophysiology of sepsis. To evaluate the functional hemostatic changes in sepsis, we evaluated coagulation profiles and flow cytometric measurement of P-selectin (CD62P) expression on platelets, as well as platelet-leukocyte aggregation from a lipopolysaccharide (LPS)-induced endotoxemia model in dogs (n = 7). A sublethal dose of LPS [1 mg/kg body weight (BW)] induced thrombocytopenia and increased activated partial thromboplastin time (aPTT), prothrombin time (PT), and D-dimer concentrations. Flow cytometry analysis showed a significant increase in P-selectin expression on platelets between 1 and 24 h of a total 48 h of the experiment. In addition, platelet-leukocyte aggregation was significantly increased in the early stage of endotoxemia (at 1 and <6 h for platelet-monocyte aggregation and at 3 h for platelet-neutrophil aggregation). Our results suggest that CD62P expression on platelets and platelet-leukocyte aggregation, as measured by flow cytometry, can be useful biomarkers of disseminated intravascular coagulation (DIC) in canine sepsis. These functional changes contribute to our understanding of the pathophysiology of hemostasis in endotoxemia.
Show more [+] Less [-]Identification of Escherichia coli F4ac-binding proteins in porcine milk fat globule membrane Full text
2015
Novaković, Predrag | Huang, Yanyun Y. | Lockerbie, Betty | Shahriar, Farshid | Kelly, John | Gordon, John R. | Middleton, Dorothy M. | Loewen, Matthew E. | Kidney, Beverly A. | Simko, Elemir
F4ac-positive enterotoxigenic Escherichia coli (ETEC) must attach to the intestinal mucosa to cause diarrhea in piglets. Prevention of bacterial attachment to the intestinal mucosa is the most effective defense against ETEC-induced diarrhea. Porcine milk fat globule membranes (MFGM) were shown to be able to inhibit attachment of ETEC to the intestinal brush border; however, the specific components of porcine MFGM that inhibited attachment of ETEC to enterocytes were not identified. Accordingly, the purpose of this study was to identify F4ac-binding MFGM proteins by overlay Western blot and affinity chromatography. The proteome of porcine MFGM was characterized and the following F4ac-binding proteins were detected by overlay Western blot and affinity chromatography: lactadherin, butyrophilin, adipophilin, acyl-CoA synthetase 3, and fatty acid-binding protein 3. The biological function of these proteins was not investigated but it is possible that their interaction with F4ac fimbria interferes with bacterial attachment and colonization.
Show more [+] Less [-]Pharmacokinetics of butorphanol delivered with an osmotic pump during a seven-day period in common peafowl (Pavo cristatus) Full text
2015
Clancy, Meredith M. | Kukanich, Butch | Sykes, John M IV
OBJECTIVE To determine pharmacokinetics of butorphanol delivered via osmotic pumps in common peafowl (Pavo cristatus) as a method for analgesic administration to avian species. ANIMALS 14 healthy adult male common peafowl. PROCEDURES A preliminary experiment was conducted with 2 birds to establish time point and concentration requirements. Then, the remaining 12 birds were anesthetized, and 2 osmotic pumps containing butorphanol (volume, 2 mL; mean dosage, 247 μg/kg/h) were implanted subcutaneously in each bird for 7 days prior to removal. Blood samples were collected before pump implantation (time 0); 3, 6, 12, 24, 48, 72, 96, 120, 144, and 168 hours after pump implantation; and 3 and 6 hours after pump removal. Plasma butorphanol concentrations were measured via liquid chromatography–mass spectrometry. RESULTS Plasma concentrations peaked (mean, 106.4 μg/L; range, 61.8 to 133.0 μg/L) at a mean of 39.0 hours, with no evidence of sedation in any bird. After pump removal, butorphanol was rapidly eliminated (half-life, 1.45 hours; range, 1.31 to 1.64 hours; n = 5). Mean clearance per fraction of dose absorbed was 2.89 L/kg/h (range, 2.00 to 5.55 L/kg/h). Mean amount of time the plasma butorphanol concentration was ≥ 60 μg/L was 85.6 hours (range, 3.5 to 155.3 hours). CONCLUSIONS AND CLINICAL RELEVANCE Plasma concentrations of butorphanol in common peafowl were maintained at or above reported efficacious analgesic concentrations. This study established a method for administering analgesics to avian patients without the need for frequent handling or injections. Use of these osmotic pumps may provide options for avian analgesia.
Show more [+] Less [-]Desflurane and sevoflurane elimination kinetics and recovery quality in horses Full text
2015
OBJECTIVE To evaluate pharmacokinetics, recovery times, and recovery quality in horses anesthetized with 1.2 times the minimum alveolar concentration of sevoflurane or desflurane. ANIMALS 6 healthy adult horses. PROCEDURES Anesthesia was maintained with sevoflurane or desflurane for 2 hours at 1.2 times the minimum alveolar concentration. Horses recovered without assistance. During recovery, end-tidal gas samples were collected until horses spontaneously moved. Anesthetic concentrations were measured by use of gas chromatography. After a 1-week washout period, horses were anesthetized with the other inhalation agent. Video recordings of anesthetic recovery were evaluated for recovery quality on the basis of a visual analogue scale by investigators who were unaware of the anesthetic administered. Anesthetic washout curves were fit to a 2-compartment kinetic model with multivariate nonlinear regression. Normally distributed interval data were analyzed by means of paired Student t tests; ordinal or nonnormally distributed data were analyzed by means of Wilcoxon signed rank tests. RESULTS Horses recovered from both anesthetics without major injuries. Results for subjective recovery evaluations did not differ between anesthetics. Area under the elimination curve was significantly smaller and time to standing recovery was significantly less for desflurane than for sevoflurane, although distribution and elimination constants did not differ significantly between anesthetics. CONCLUSIONS AND CLINICAL RELEVANCE Differences in area under elimination the curve between anesthetics indicated more rapid clearance for desflurane than for sevoflurane in horses, as predicted by anesthetic blood solubility differences in this species. More rapid elimination kinetics was associated with faster recovery times, but no association with improved subjective recovery quality was detected.
Show more [+] Less [-]Association of bovine respiratory disease or vaccination with serologic response in dairy heifer calves up to three months of age Full text
2015
Windeyer, M Claire | Leslie, Ken E. | Godden, Sandra M. | Hodgins, Douglas C. | Lissemore, Kerry D. | LeBlanc, Stephen J.
OBJECTIVE To investigate the association of bovine respiratory disease (BRD) or vaccination with serologic response in calves. ANIMALS 94 Holstein calves. PROCEDURES To assess the association between BRD and antibody titers, 38 calves < 3 months old that were treated for BRD were matched with 38 untreated calves. To investigate the effect of vaccination on antibody titers, 24 calves were randomly assigned to be vaccinated against bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus types 1 and 2, bovine herpesvirus type 1 (BHV1), and parainfluenza virus type 3 at 2 weeks of age (n = 6), 5 weeks of age (6), and both 2 and 5 weeks of age (6) or were assigned to be unvaccinated controls (6). Blood samples were obtained at I, 2, 5, and 12 weeks for determination of serum neutralization antibody titers against the vaccine viruses, bovine coronavirus, and Mannheimia haemolytica. Antibody rates of decay were calculated. RESULTS Calves with initial antibody titers against BRSV < 1:64 that were treated for BRD had a slower rate of anti-BRSV antibody decay than did similar calves that were not treated for BRD. Calves with high initial antibody titers against BRSV and BHV1 had lower odds of BRD than did calves with low initial antibody titers against those 2 pathogens. Vaccination at 2 or 5 weeks of age had no effect on the rate of antibody decay. CONCLUSIONS AND CLINICAL RELEVANCE Clinical BRD and the serologic response of dairy calves were associated with initial antibody titers against BRSV and BHV1. Serologic or clinical responses to viral exposure may differ in calves with low passive immunity.
Show more [+] Less [-]West Nile virus–specific immunoglobulin isotype responses in vaccinated and infected horses Full text
2015
Khatibzadeh, Sarah M. | Gold, Carvel B. | Keggan, Alison E. | Perkins, Gillian A. | Glaser, Amy L. | Dubovi, Edward J. | Wagner, Bettina
OBJECTIVE To compare antibody responses of horses naturally infected with West Nile virus (WNV) and those vaccinated against WNV, to identify whether vaccination interferes with the ability to diagnose WNV infection, and to determine the duration of antibody responses after vaccination. SAMPLE Sera from horses naturally infected with WNV (n = 10) and adult WNV-naïve horses before and after vaccination with a live canarypox virus–vectored vaccine (7) or a killed virus vaccine (8). PROCEDURES An established WNV IgM capture ELISA was used to measure IgM responses. Newly developed capture ELISAs were used to measure responses of 8 other WNV-specific immunoglobulin isotypes. A serum neutralization assay was used to determine anti-WNV antibody titers. RESULTS WNV-specific IgM responses were typically detected in the sera of WNV-infected horses but not in sera of horses vaccinated against WNV. Natural infection with and vaccination against WNV induced an immunoglobulin response that was primarily composed of IgG1. West Nile virus–specific IgG1 was detected in the sera of most horses 14 days after vaccination. Serum anti-WNV IgG1 and neutralizing antibody responses induced by the killed-virus vaccines were higher and lasted longer than did those induced by the live canarypox virus–vectored vaccine. CONCLUSIONS AND CLINICAL RELEVANCE On the basis of these findings, we recommend that horses be vaccinated against WNV annually near the beginning of mosquito season, that both IgM and IgG1 responses against WNV be measured to distinguish between natural infection and vaccination, and that a WNV IgG1 ELISA be used to monitor anti-WNV antibodies titers in vaccinated horses.
Show more [+] Less [-]In vitro mechanical evaluation of equine laryngeal tie-forward constructs prepared with different suture materials and placement patterns Full text
2015
Santos, Marcos P. | Gutierrez-Nibeyro, Santiago D. | Horn, Gavin P. | Hicke, Joshua D. | Stewart, Matthew C. | Schaeffer, David J.
OBJECTIVE To compare the mechanical properties of laryngeal tie-forward (LTF) constructs prepared with different suture materials and suture placement patterns during single load to failure testing. SAMPLE Larynges harvested from 50 horse cadavers and 5 intact horse cadavers. PROCEDURES In vitro LTF constructs were created by a standard technique with polyester sutures, a standard technique with polyethylene sutures, a modified technique with metallic implants and polyester sutures, a modified technique with metallic implants and polyethylene sutures, or a modified tie-off technique with polyester sutures (10 of each type of construct). Mechanical properties including maximal load (N) at failure and failure mode were compared among constructs. Also, maximal loads at failure of the in vitro LTF constructs were compared with the loads exerted on the sutures tightened to achieve rostral laryngeal advancement in intact cadavers. RESULTS Constructs prepared by a standard technique with polyethylene sutures had a significantly higher pull out strength than those prepared by a modified technique with metallic implants and either polyester or polyethylene sutures. For constructs prepared by a standard technique with polyethylene sutures or similarly placed polyester sutures, maximal load at failure did not differ but the failure mode did differ significantly. The load to failure for all in vitro constructs was higher than the maximal load measured during a range of motion test in intact horse cadavers. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that LTF procedures can be performed in live horses with any of the suture materials and techniques tested.
Show more [+] Less [-]Temporospatial and kinetic gait variables of Doberman Pinschers with and without cervical spondylomyelopathy Full text
2015
Lima, Carolina G. D. | Da Costa, Ronaldo C. | Foss, Kari D. | Allen, Matthew J.
OBJECTIVE To characterize and compare gait variables in Doberman Pinschers with and without cervical spondylomyelopathy (CSM). ANIMALS 18 Doberman Pinschers (9 clinically normal dogs and 9 CSM-affected dogs). PROCEDURES A neurologic examination was performed on all dogs. The diagnosis of CSM was confirmed with MRI. Temporospatial and kinetic gait variables were measured by use of a pressure-sensitive walkway. Temporospatial variables evaluated included stance phase duration, swing phase duration, gait cycle duration, stride length, and gait velocity. Kinetic variables evaluated included peak vertical force and vertical impulse. Random-effects linear regression was used to determine the difference between CSM-affected and clinically normal dogs for each of the 7 variables. RESULTS Values for temporospatial variables were significantly smaller in the thoracic limbs of CSM-affected dogs, compared with values for the thoracic limbs of clinically normal dogs. For the kinetic variables, peak vertical force was significantly higher in the thoracic limbs than the pelvic limbs for all dogs. Vertical impulse values were higher in the thoracic limbs than the pelvic limbs. There were significant differences in mean vertical impulse between the thoracic and pelvic limbs for both groups. CONCLUSIONS AND CLINICAL RELEVANCE In this study, significant differences in temporospatial variables were identified between the thoracic limbs of clinically normal and CSM-affected dogs, with the values being smaller for the CSM-affected dogs than for the clinically normal dogs. A pressure-sensitive walkway may provide a valid, practical option for rapid, objective assessment of gait and response to treatment in dogs with CSM.
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