Poultry has been identified as a reservoir of foodborne enteric pathogens and antimicrobial resistant bacteria. The objective of this study was to describe and compare antimicrobial resistant isolates from an Ontario broiler chicken farm-level baseline project (2003 to 2004) to the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) Ontario abattoir and retail surveillance data from 2003, and to the most recent (2015) CIPARS Ontario chicken surveillance data in order to assess the impact of an industry-wide policy change in antimicrobial use. Ceftiofur resistance (TIO-R) prevalence in Salmonella decreased by 7% on farm between 2003 and 2004 and 2015. During the same timeframe, TIO-R E. coli prevalence decreased significantly by 16%, 11%, and 8% in farm, abattoir, and retail samples, respectively. Gentamicin resistant (GEN-R) E. coli, however, increased by 10% in farm and 15% in retail-derived isolates, and trimethoprim-sulfamethoxazole resistant (TMSm-R) E. coli increased significantly by 20%, 18%, and 5% in farm, abattoir, and retail isolates, respectively. Similarly, ciprofloxacin-resistant (CIP-R) Campylobacter spp. significantly increased in retail isolates by 11% and increased in farm (33%) and abattoir isolates (7%). The decrease in TIO-R Salmonella/E. coli in recent years is consistent with the timing of an industry-led intervention eliminating the preventive use of ceftiofur, a third generation cephalosporin and class of antimicrobials deemed critically important to human medicine. The rise in GEN-R and TMSm-R prevalence is indicative of recent shifts in antimicrobial use. Our study highlights the importance of integrated surveillance in detecting emerging trends and determining the efficacy of interventions to improve food safety.

OBJECTIVE To evaluate the effect of 2 bronchoalveolar lavage (BAL) sampling techniques and the use of N-butylscopolammonium bromide (NBB) on the quantity and quality of BAL fluid (BALF) samples obtained from horses with the summer pasture endophenotype of equine asthma. ANIMALS 8 horses with the summer pasture endophenotype of equine asthma. PROCEDURES BAL was performed bilaterally (right and left lung sites) with a flexible videoendoscope passed through the left or right nasal passage. During lavage of the first lung site, a BALF sample was collected by means of either gentle syringe aspiration or mechanical suction with a pressure-regulated wall-mounted suction pump. The endoscope was then maneuvered into the contralateral lung site, and lavage was performed with the alternate fluid retrieval technique. For each horse, BAL was performed bilaterally once with and once without premedication with NBB (21-day interval). The BALF samples retrieved were evaluated for volume, total cell count, differential cell count, RBC count, and total protein concentration. RESULTS Use of syringe aspiration significantly increased total BALF volume (mean volume increase, 40 mL [approx 7.5% yield]) and decreased total RBC count (mean decrease, 142 cells/μL), compared with use of mechanical suction. The BALF nucleated cell count and differential cell count did not differ between BAL procedures. Use of NBB had no effect on BALF retrieval. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that retrieval of BALF by syringe aspiration may increase yield and reduce barotrauma in horses at increased risk of bronchoconstriction and bronchiolar collapse. Further studies to determine the usefulness of NBB and other bronchodilators during BAL procedures in horses are warranted.

OBJECTIVE To determine the pharmacokinetics of florfenicol, terbinafine, and betamethasone acetate after topical application to canine auricular skin and the influence of synthetic canine cerumen on pharmacokinetics. SAMPLE Auricular skin from 6 euthanized shelter dogs (3 females and 3 neutered males with no visible signs of otitis externa). PROCEDURES Skin adjacent to the external opening of the ear canal was collected and prepared for use in a 2-compartment flow-through diffusion cell system to evaluate penetration of an otic gel containing florfenicol, terbinafine, and betamethasone acetate over a 24-hour period. Radiolabeled 14C-terbinafine hydrochloride and 3H-betamethasone acetate were added to the gel to determine dermal penetration and distribution. Florfenicol absorption was determined by use of high-performance liquid chromatography–UV detection. Additionally, the effect of synthetic canine cerumen on the pharmacokinetics of all compounds was evaluated. RESULTS During the 24-hour experiment, mean ± SD percentage absorption without the presence of synthetic canine cerumen was 0.28 ± 0.09% for 3H-betamethasone acetate, 0.06 ± 0.06% for florfenicol, and 0.06 ± 0.02% for 14C-terbinafine hydrochloride. Absorption profiles revealed no impact of synthetic canine cerumen on skin absorption for all 3 active compounds in the gel or on skin distribution of 3H-betamethasone acetate and 14C-terbinafine hydrochloride. CONCLUSIONS AND CLINICAL RELEVANCE 3H-betamethasone acetate, 14C-terbinafine hydrochloride, and florfenicol were all absorbed in vitro through healthy auricular skin specimens within the first 24 hours after topical application. Synthetic canine cerumen had no impact on dermal absorption in vitro, but it may serve as a temporary reservoir that prolongs the release of topical drugs.

The aim of this study was to develop a droplet digital polymerase chain reaction (ddPCR) method to detect African swine fever virus (ASFV). The methods of ASFV real-time PCR and ddPCR were established and optimal reaction conditions were confirmed. Each method was evaluated for linearity, limit of detection, and specificity. The results indicated that ASFV ddPCR had a high degree of linearity (R2 ≥ 0.998) and specificity. The detection limit was 10 copies/reaction, which was approximately a 10-fold greater sensitivity than real-time PCR. This sensitive method could be used as an efficient molecular biology tool to diagnose ASFV, which is very important for preventing the spread of diseases across borders.

OBJECTIVE To evaluate cell-mediated and humoral immune responses of calves receiving 2 doses of a dual-adjuvanted vaccine containing inactivated bovine herpesvirus type 1 (BHV1) and bovine viral diarrhea virus types 1 (BVDV1) and 2 (BVDV2) before and after exposure to BHV1. ANIMALS 24 Holstein steers negative for anti-BHV1 antibodies and proliferative cell-mediated immune responses against BHV1 and BVDV. PROCEDURES Calves were randomly assigned to 3 groups. The vaccinated group (n = 10) received 2 doses of vaccine on days 0 and 21. Control (n = 10) and seeder (4) groups remained unvaccinated. Calves were commingled during the study except for the 3-day period (days 53 to 55) when seeders were inoculated with BHV1 (1.04 × 107 TCID50, IV) to serve as a source of virus for challenge (days 56 through 84). Rectal temperature and clinical illness scores were monitored, and blood and nasal specimens were obtained for determination of clinicopathologic and immunologic variables. RESULTS After BHV1 challenge, mean rectal temperature and clinical illness scores were lower for vaccinates than controls. In vaccinates, antibody titers against BHV1 and BVDV2, but not BVDV1, increased after challenge as did extracellular and intracellular interferon-γ expression, indicating a T helper 1 memory response. Additional results of cell marker expression were variable, with no significant increase or decrease associated with treatment. CONCLUSIONS AND CLINICAL RELEVANCE Calves administered 2 doses of a killed-virus vaccine developed cell-mediated and humoral immune responses to BHV1 and BVDV, which were protective against disease when those calves were subsequently exposed to BHV1.

OBJECTIVE To compare the efficacy of application of an alcohol-based antiseptic (80% ethyl alcohol) hand rub (ABAHR) with that of a 2% chlorhexidine gluconate scrub (CGS2) for immediate reduction of the bacterial population on the skin of dogs. ANIMALS 50 client-owned dogs with no evidence of skin disease. PROCEDURES On each dog, 2 areas of hair on the ventral aspect of the abdomen were clipped with a No. 40 blade and cleared of debris. A direct contact plate holding tryptic soy agar with polysorbate 80 and lecithin was gently pressed (for 2 seconds) on each skin site (preapplication sample). The CGS2 and ABAHR were each aseptically applied to 1 skin site on each dog. A direct contact plate was subsequently applied to each site in a similar manner (postapplication sample). All plates were cultured, and bacterial isolates were identified and quantified by the number of CFUs per plate. RESULTS Application of the CGS2 and ABAHR significantly decreased skin bacterial colony counts, compared with findings for preapplication samples. The number of CFUs per plate or postapplication percentage reduction in CFUs per plate did not differ between treatments. There were no adverse skin reactions associated with either application. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that applications of ABAHR and CGS2 were equally effective at immediately reducing the bacterial population on the skin of dogs, and there was no significant difference in percentage reduction in colony counts between the 2 applications.

Although mesenchymal stem cells (MSCs) are now regarded as a promising cell resource for tissue repair and regeneration, the optimal source of MSCs has not yet been determined. The objective of this study was to provide a theoretical basis for the clinical application of umbilical cord mesenchymal stem cells (UCMSCs) in the future. Umbilical cord is an easily obtainable tissue resource, which is one reason that it has become a candidate resource for mesenchymal stem cells. In this study, we analyzed the biological characteristics of UCMSCs, such as their multiple differentiation and clone-forming ability, through morphological observation, reverse transcription polymerase chain reaction (RT-PCR), growth curve, positive rate test, and immunophenotype. Umbilical cord MSCs were successfully isolated and passaged to 29 generations. The results from RT-PCR showed that UCMSCs were positive for CD29, CD44, CD73, but negative for CD34. The expression of the stem cell marker nucleostemin and tenocyte-related markers showed similar positive results with CD44, CD73, and CD90. In addition, UCMSCs can be induced to differentiate into osteoblasts, adipocytes, or chondrocytes. Our study showed that UCMSCs not only have the ability to self-renew, but also have the potential to differentiate into multiple lineages. In general, we concluded that UCMSCs are a reliable source for use in cell therapy.

OBJECTIVE To evaluate accuracy of quantification of right ventricle volume (RVV) by use of 3-D echocardiography (3DE) and ECG-gated multidetector CT (MDCT). ANIMALS 6 healthy hound-cross dogs. PROCEDURES ECG-gated MDCT and complete 3DE examinations were performed on each dog. Right ventricular end-diastolic volumes (EDVs), end-systolic volumes (ESVs), stroke volume (SV), and ejection fraction (EF) were measured for 3DE and MDCT data sets by use of software specific for RVV quantification. Correlation and level of agreement between methods were determined. Intraobserver and interobserver variability were assessed for 3DE. RESULTS No significant differences were detected between SV and EF obtained with MDCT and 3DE. Significant differences were detected between right ventricular EDV and ESV obtained with MDCT and 3DE. No significant difference in heart rate was detected between methods. The correlation between MDCT and 3DE was very good (r = 0.87) for EDV and ESV, moderate (r = 0.60) for EF, and poor (r = 0.31) for SV. Bland-Altman analysis revealed a systematic underestimation of RVV derived by use of 3DE, compared with the RVV derived by use of MDCT (mean bias, 15 and 10.3 mL for EDV and ESV, respectively). Intraobserver (EDV, 12%; ESV, 18%) and interobserver (EDV, 14%; ESV, 11%) variability were acceptable for 3DE. CONCLUSIONS AND CLINICAL RELEVANCE There was substantial variance for RVV measured by use of 3DE in healthy dogs and a significant underestimation of volumes, compared with results for MDCT, despite the fact there were no significant differences in SV and EF.

OBJECTIVE To investigate use of the plethysmographic variability index (PVI) and perfusion index (PI) for evaluating changes in arterial blood pressure in anesthetized tigers (Panthera tigris). ANIMALS 8 adult tigers. PROCEDURES Each tiger was anesthetized once with a combination of ketamine, midazolam, medetomidine, and isoflurane. Anesthetic monitoring included assessment of PI, PVI, direct blood pressure measurements, anesthetic gas concentrations, esophageal temperature, and results of capnography and ECG. Mean arterial blood pressure (MAP) was maintained for at least 20 minutes at each of the following blood pressure conditions: hypotensive (MAP = 50 ± 5 mm Hg), normotensive (MAP = 70 ± 5 mm Hg), and hypertensive (MAP = 90 ± 5 mm Hg). Arterial blood gas analysis was performed at the beginning of anesthesia and at each blood pressure condition. RESULTS Mean ± SD PI values were 1.82 ± 2.38%, 1.17 ± 0.77%, and 1.71 ± 1.51% and mean PVI values were 16.00 ± 5.07%, 10.44 ± 3.55%, and 8.17 ± 3.49% for hypotensive, normotensive, and hypertensive conditions, respectively. The PI values did not differ significantly among blood pressure conditions. The PVI value for the hypotensive condition differed significantly from values for the normotensive and hypertensive conditions. The PVI values were significantly correlated with MAP (r = −0.657). The OR of hypotension to nonhypotension for PVI values ≥ 18% was 43.6. CONCLUSIONS AND CLINICAL RELEVANCE PVI was a clinically applicable variable determined by use of noninvasive methods in anesthetized tigers. Values of PVI ≥ 18% may indicate hypotension.

OBJECTIVE To determine reference intervals for total nucleated cell count, total protein concentration, pH, RBC count, and percentages of neutrophils, lymphocytes, and large mononuclear cells in synovial fluid samples (SFSs) obtained from the carpal and tarsal joints of healthy swine. ANIMALS 54 healthy commercial finisher pigs that had no evidence of lameness or gross joint swelling. PROCEDURES Each pig was anesthetized, and SFSs were collected from 1 carpal and 1 tarsal joint for fluid analysis, cytologic evaluation, bacterial culture, and PCR analyses for common swine joint pathogens. Each pig was euthanized after SFS collection, and synovial tissue samples were collected for histologic assessment. If necessary, postmortem SFSs were collected. RESULTS Overall, 37 of 50 tarsal and 46 of 53 carpal SFSs met inclusion criteria of sufficient volume, no gross blood contamination, and negative results of bacterial culture and PCR analyses, and were from joints with histologically normal synovial tissues. For the carpal and tarsal joints, upper reference limits were as follows: total nucleated cell count, 3,281 cells/μL and 2,368 cells/μL, respectively; total protein concentration, 3.6 g/dL and 3.6 g/dL, respectively; pH, 7.2 and 7.0, respectively; RBC count, 0.8 × 10(6) cells/μL and 0.1 × 10(6) cells/μL, respectively; and percentage of neutrophils, 46.5% and 33.7%, respectively; percentage of lymphocytes, 40.6% and 56.3%, respectively; and percentage of large mononuclear cells, 92.0% and 95.3%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results have provided reference intervals for selected variables in SFSs obtained from the carpal and the tarsal joints of healthy swine, which should be useful in diagnostic investigations of swine lameness and arthritis.