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Ex vivo penetration of low-level laser light through equine skin and flexor tendons
2016
Duesterdieck-Zellmer, Katja F. | Larson, Maureen K. | Plant, Thomas K. | Sundholm-Tepper, Andrea | Payton, Mark E.
OBJECTIVE To measure penetration efficiencies of low-level laser light energy through equine skin and to determine the fraction of laser energy absorbed by equine digital flexor tendons (superficial [SDFT] and deep [DDFT]). SAMPLE Samples of skin, SDFTs, and DDFTs from 1 metacarpal area of each of 19 equine cadavers. PROCEDURES A therapeutic laser with wavelength capabilities of 800 and 970 nm was used. The percentage of energy penetration for each wavelength was determined through skin before and after clipping and then shaving of hair, through shaved skin over SDFTs, and through shaved skin, SDFTs, and DDFTs (positioned in anatomically correct orientation). Influence of hair color; skin preparation, color, and thickness; and wavelength on energy penetration were assessed. RESULTS For haired skin, energy penetration was greatest for light-colored hair and least for dark-colored hair. Clipping or shaving of skin improved energy penetration. Light-colored skin allowed greatest energy penetration, followed by medium-colored skin and dark-colored skin. Greatest penetration of light-colored skin occurred with the 800-nm wavelength, whereas greatest penetration of medium- and dark-colored skin occurred with the 970-nm wavelength. As skin thickness increased, energy penetration of samples decreased. Only 1% to 20% and 0.1% to 4% of energy were absorbed by SDFTs and DDFTs, respectively, depending on skin color, skin thickness, and applied wavelength. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that most laser energy directed through equine skin was absorbed or scattered by the skin. To achieve delivery of energy doses known to positively affect cells in vitro to equine SDFTs and DDFTs, skin preparation, color, and thickness and applied wavelength must be considered.
Mostrar más [+] Menos [-]Goniometrie evaluation of standing extension and maximum flexion joint angles of llamas and alpacas
2016
Walters, Amy L. | Semevolos, Stacy A. | Baker, Rose E.
OBJECTIVE To determine and compare mean standing extension and maximum flexion angles of various joints in healthy adult alpacas and llamas, and determine the reliability of goniometric data within and between 2 observers for each joint of interest. SAMPLE 6 healthy adult llamas and 6 healthy adult alpacas. PROCEDURES The shoulder joint, elbow joint, carpal, and metacarpophalangeal (MCP) joints of the forelimbs and the hip joint, stifle joint, tarsal, and metatarsophalangeal (MTP) joints of the hind limbs were investigated. Each articulation was measured with a universal goniometer by 2 observers, who each obtained 2 measurements when each joint was maintained in standing extension and in maximal passive flexion. Two sample (unpaired) t tests were performed for comparisons of mean standing extension and maximum passive flexion angles between alpacas and llamas. Intraclass correlation coefficients were calculated for each articulation to assess interobserver and intra-observer reliability of measurements. RESULTS Llamas had larger mean standing extension angles than alpacas for the tarsal and elbow joint, but there were no significant differences between species for all other joints. For all joints, flexion measurements did not differ significantly between the 2 species. For most joints, the reliability of goniometric data between observers was good to excellent (intraclass correlation coefficients, 0.6 to 0.95) CONCLUSIONS AND CLINICAL RELEVANCE Except for the elbow joint and tarsus in extension, the angle of limb articulations during flexion and extension can be considered similar for alpacas and llamas. These measurements have relevance for veterinary surgeons when assessing joint mobility and conformation and determining appropriate angles for arthrodesis.
Mostrar más [+] Menos [-]Effects on indicators of tissue perfusion in dogs anesthetized with isoflurane at two multiples of the minimum alveolar concentration
2016
Floriano, Beatriz P. | Wagatsuma, Juliana T. | Ferreira, Joana Z. | Abimussi, Caio J. X. | Menegheti, Thais M. | Santos, Paulo S. P. | Oliva, Valeria N. L. S.
OBJECTIVE To investigate the effects of isoflurane anesthesia administered at 2 multiples of the minimum alveolar concentration (MAC) on tissue perfusion in dogs. ANIMALS 8 healthy young adult Beagles. PROCEDURES A randomized crossover design was used. Dogs were anesthetized with isoflurane at 1.5 or 2.0 times the MAC for 2 hours, a 7-day washout period was provided, and dogs were reanesthetized with the alternate treatment. Various physiologic variables were monitored before anesthesia (baseline), at 20-minute intervals during anesthesia, and after anesthetic recovery. Variable values were compared between MAC multiples by means of repeated-measures ANOVA, with the Tukey test used for multiple comparisons. RESULTS During anesthesia, mean arterial blood pressure, cardiac output, and mixed venous oxygen saturation were significantly greater when isoflurane was administered at 1.5 versus 2.0 times the MAC. Cardiac output gradually increased during anesthesia at 1.5 times but not at 2.0 times the MAC. Arterial blood lactate concentration did not differ between MAC multiples at any point; however, this concentration decreased with increasing anesthetic duration at both MAC multiples. Oxygen delivery differed between MAC multiples, and oxygen consumption differed from baseline during anesthesia at 2.0 times the MAC. Oxygen extraction was higher at 2.0 versus 1.5 times the MAC. Heart rate differed between MAC multiples only after anesthetic recovery. CONCLUSIONS AND CLINICAL RELEVANCE Isoflurane anesthesia impaired tissue perfusion in dogs, but these changes would not be clinically relevant with oxygen delivery at 100%. Peripheral tissue perfusion was maintained or improved with time.
Mostrar más [+] Menos [-]Protective efficacy by various doses of Salmonella ghost vaccine candidate carrying enterotoxigenic Escherichia coli fimbrial antigen against neonatal piglet colibacillosis
2016
Jin, Hur | Lee, John Hwa
Humoral immune responses and protective efficacy by various doses of Salmonella ghost cells carrying enterotoxigenic Escherichia coli (ETEC) fimbrial antigens for protection against piglet colibacillosis were studied. All groups were orally primed and boosted at 11 and 14 wk of pregnancy, respectively. Group A sows were inoculated with phosphate-buffered saline (PBS), and groups B, C, and D sows were immunized with 2 × 10(9) 2 × 10(10), and 2 × 10(11) ghost cells, respectively. Serum immunoglobulin (Ig)G, and colostrum (Ig)G and (Ig)A levels of groups C and D sows were significantly higher than those of group A sows. In addition, serum (Ig)G and (Ig)A levels in group C and D piglets were significantly increased compared to those of group A piglets. After challenge with wild-type ETEC, diarrhea and mortality were not observed in group C and D piglets, while diarrhea was observed in 88.9% and 58.8% of groups A and B piglets, respectively, and 16.7% mortality was observed in group A piglets. These findings indicate that oral immunization of sows with 2 × 1010 or 1011 ghost cells can effectively protect their offspring from colibacillosis.
Mostrar más [+] Menos [-]Assessment of frailty in aged dogs
2016
Hua, Julie | Hoummady, Sara | Müller, Claude | Pouchelon, Jean-Louis | Blondot, Marc | Gilbert, Caroline | Desquilbet, Loic
OBJECTIVE To define a frailty-related phenotype—a clinical syndrome associated with the aging process in humans—in aged dogs and to investigate its association with time to death. ANIMALS 116 aged guide dogs. PROCEDURES Dogs underwent a clinical geriatric assessment (CGA) and were followed to either time of death or the study cutoff date. A 5-component clinical definition of a frailty phenotype was derived from clinical items included in a geriatric health evaluation scoresheet completed by veterinarians during the CGA. Univariate (via Kaplan-Meier curves) and multivariate (via Cox proportional hazards models) survival analyses were used to investigate associations of the 5 CGA components with time to death. RESULTS 76 dogs died, and the median time from CGA to death was 4.4 years. Independent of age at the time of CGA, dogs that had ≥ 2 of the 5 components (n = 10) were more likely to die during the follow-up period, compared with those that had 1 or no components (adjusted hazard ratio, 3.9 [95% confidence interval, 1.4 to 10.9]). After further adjustments for subclinical or clinical diseases and routine biomarkers, the adjusted hazard ratio remained significant. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that signs of frailty appeared to be a risk factor for death in dogs. The concept of frailty in dogs requires further development. IMPACT FOR HUMAN MEDICINE The concept of frailty, as defined for humans, seems transposable to dogs. Given that they share humans' environments and develop several age-related diseases similar to those in humans, dogs may be useful for the study of environmental or age-related risk factors for frailty in humans.
Mostrar más [+] Menos [-]Comparison of antibacterial effects among three foams used with negative pressure wound therapy in an ex vivo equine perfused wound model
2016
Hecke, Lore L Van | Haspeslagh, Maarten | Hermans, Katleen | Martens, Ann M.
OBJECTIVE To compare antibacterial effects among 3 types of foam used with negative-pressure wound therapy (NPWT) in an ex vivo equine perfused wound model. SAMPLES Abdominal musculocutaneous flaps from 6 equine cadavers. PROCEDURES Each musculocutaneous flap was continuously perfused with saline (0.9% NaCl) solution. Four 5-cm circular wounds were created in each flap and contaminated with 106 CFUs of both Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA). After a 1-hour incubation period, 1 of 4 treatments (NPWT with silver-impregnated polyurethane foam [NPWT-AgPU], polyurethane foam [NPWT-PU], or polyvinyl alcohol foam [NPWT-PVA] or a nonadherent dressing containing polyhexamethylene biguanide without NPWT [control]) was randomly applied to each wound. An 8-mm punch biopsy specimen was obtained from each wound immediately before and at 6, 12, 18, and 24 hours after treatment application to determine the bacterial load for both P aeruginosa and MRSA. RESULTS The bacterial load of P aeruginosa for the NPWT-PVA treatment was significantly lower than that for the other 3 treatments at each sampling time after application, whereas the bacterial load for the NPWT-AgPU treatment was significantly lower than that for the NPWT-PU and control treatments at 12 hours after application. The bacterial load of MRSA for the NPWT-PVA treatment was significantly lower than that for the other 3 treatments at each sampling time after application. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that wounds treated with NPWT-PVA had the greatest decrease in bacterial load; however, the effect of that treatment on wound healing needs to be assessed in vivo.
Mostrar más [+] Menos [-]Pharmacokinetics of zonisamide following rectal administration to healthy dogs
2016
Michaels, Jennifer R. | Hodshon, Amy J. | Thomas, William B. | Boothe, Dawn M. | Williams, Lindsay
OBJECTIVE To evaluate the pharmacokinetics of zonisamide following rectal administration of 20 or 30 mg/kg suspended in sterile water or polyethylene glycol (PEG) to healthy dogs and determine whether either dose resulted in plasma zonisamide concentrations within the recommended therapeutic target range (10 to 40 μg/mL). ANIMALS 8 healthy mixed-breed dogs. PROCEDURES Each dog received each of 2 doses (20 or 30 mg/kg) of zonisamide suspended in each of 2 delivery substrates (sterile water or PEG) in a randomized crossover study with a 7-day washout period between phases. A blood sample was collected from each dog immediately before and at predetermined times for 48 hours after zonisamide administration. Plasma zonisamide concentrations were determined by high-performance liquid chromatography, and data were analyzed with a noncompartmental model. RESULTS Mean maximum plasma concentration, time to maximum plasma concentration, mean residence time, and elimination half-life did not differ significantly among the 4 treatments. The mean maximum plasma concentration for all 4 treatments was less than the therapeutic target range. The mean ± SD area under the concentration-time curve for the 30 mg/kg-in-water treatment (391.94 ± 237.00 h•μg/mL) was significantly greater than that for the 20 mg/kg-in-water (146.19 ± 66.27 h•μg/mL) and 20 mg/kg-in-PEG (87.09 ± 96.87 h•μg/mL) treatments. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that rectal administration of zonisamide at doses of 20 and 30 mg/kg failed to achieve plasma zonisamide concentrations within the recommended therapeutic target range. Therefore, rectal administration of zonisamide cannot be recommended as a suitable alternative to oral administration.
Mostrar más [+] Menos [-]Association between thermal environment and Salmonella in fecal samples from dairy cattle in midwestern United States
2016
Likavec, Tasha | Pires, Alda F. A. | Funk, Julie A.
The objective of this study was to describe the association between thermal measures in the barn environment (pen temperature and humidity) and fecal shedding of Salmonella in dairy cattle. A repeated cross-sectional study was conducted within a commercial dairy herd located in the midwestern United States. Five pooled fecal samples were collected monthly from each pen for 9 mo and submitted for microbiological culture. Negative binomial regression methods were used to test the association [incidence rate ratio (IRR)] between Salmonella pen status (the count of Salmonella-positive pools) and thermal environmental parameters [average temperature and temperature humidity index (THI)] for 3 time periods (48 h, 72 h, and 1 wk) before fecal sampling. Salmonella was cultured from 10.8% [39/360; 95% confidence interval (CI): 7.8% to 14.5%] of pooled samples. The highest proportion of positive pools occurred in August. The IRR ranged from 1.26 (95% CI: 1.15 to 1.39, THI 1 wk) to 4.5 (95% CI: 2.13 to 9.51, heat exposure 1 wk) across all thermal parameters and lag time periods measured. For example, the incidence rate of Salmonella-positive pools increased by 54% for every 5°C increment in average temperature (IRR = 1.54; 95% CI: 1.29 to 1.85) and 29% for every 5-unit increase in THI (IRR = 1.29; 95% CI: 1.16 to 1.42) during the 72 h before sampling. The incidence rate ratio for pens exposed to higher temperatures (> 25°C) was 4.5 times (95% CI: 2.13 to 9.51) the incidence rate ratio for pens exposed to temperatures < 25°C in the 72 h before sampling. Likewise, the incidence rate ratio for pens exposed to THI > 70 was 4.23 times greater (95% CI: 2.1 to 8.28) than when the THI was < 70 in the 72 h before sampling. An association was found between the thermal environment and Salmonella shedding in dairy cattle. Further research is warranted in order to fully understand the component risks associated with the summer season and increased Salmonella shedding.
Mostrar más [+] Menos [-]Effect of sensor location in dogs on performance of an interstitial glucose monitor
2016
Koenig, Amie | Hoenig, Margarethe E. | Jimenez, David A.
OBJECTIVE To identify variations in glucose values concurrently obtained by use of a continuous glucose monitoring system (CGMS) at the same site, reliability of results for each site, lag time for each site, and influence of site thickness on CGMS accuracy. ANIMALS 8 random-source research dogs. PROCEDURES In experiment 1, 8 CGMS sensors were implanted bilaterally at 1 site (4 sensors/side) in 4 dogs. In experiment 2, 2 CGMS sensors were implanted bilaterally at each of 4 sites (1 sensor/side) in 8 dogs; 4 of those 8 dogs then were subjected to a glycemic clamp technique. The CGMS results were compared among sensors and with criterion-referenced results during periods of euglycemia for all 8 dogs and during hyperglycemia and hypoglycemia for 4 dogs during the glycemic clamp procedure. RESULTS Differences (median, −7 mg/dL; interquartile range [IQR], −18.75 to 3 mg/dL) between CGMS and criterion-referenced glucose concentrations differed significantly among dogs and sites; during euglycemia, they were not different from the expected normal variation between multiple sensors concurrently implanted at the same site. Differences (median, −35 mg/dL; IQR, −74 to −15 mg/dL) between CGMS and criterion-referenced concentrations were greater during changes in glucose concentrations. Thoracic sensors were most accurate but had the shortest mean functional life. CONCLUSIONS AND CLINICAL RELEVANCE Significant differences were detected between CGMS and criterion-referenced glucose concentrations. Overall clinical utility of CGMS was acceptable at all sites, with most of the values from all sensors, sites, and dogs meeting guidelines for point-of-care glucometers.
Mostrar más [+] Menos [-]Detection of hemoplasma infection of goats by use of a quantitative polymerase chain reaction assay and risk factor analysis for infection
2016
Johnson, Kathy A. | Nascimento, Naila C do | Bauer, Amy E. | Weng, Hsin-Yi | Hammac, Kenitra | Messick, Joanne B.
OBJECTIVE To develop and validate a real-time quantitative PCR (qPCR) assay for the detection and quantification of Mycoplasma ovis in goats and investigate the prevalence and risk factors for hemoplasma infection of goats located in Indiana. ANIMALS 362 adult female goats on 61 farms. PROCEDURES Primers were designed for amplification of a fragment of the dnaK gene of M ovis by use of a qPCR assay. Blood samples were collected into EDTA-containing tubes for use in total DNA extraction, blood film evaluation, and determination of PCV. Limit of detection, intra-assay variability, interassay variability, and specificity of the assay were determined. RESULTS Reaction efficiency of the qPCR assay was 94.45% (R2, 0.99; slope, −3.4623), and the assay consistently detected as few as 10 copies of plasmid/reaction. Prevalence of infection in goats on the basis of results for the qPCR assay was 18.0% (95% confidence interval, 14% to 22%), with infected goats ranging from 1 to 14 years old, whereby 61% (95% confidence interval, 47% to 73%) of the farms had at least 1 infected goat. Bacterial load in goats infected with M ovis ranged from 1.05 × 103 target copies/mL of blood to 1.85 × 105 target copies/mL of blood; however, no bacteria were observed on blood films. Production use of a goat was the only risk factor significantly associated with hemoplasma infection. CONCLUSIONS AND CLINICAL RELEVANCE The qPCR assay was more sensitive for detecting hemoplasma infection than was evaluation of a blood film, and production use of a goat was a risk factor for infection.
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