OBJECTIVE To determine the extent of environmental exposure to heteroxenous coccidia from wild canid feces in southeastern Ohio. SAMPLE 285 presumed wild canid fecal samples collected across an ecological system in southeastern Ohio. PROCEDURES Morphological classification and molecular analysis were used to determine the canid genus for collected fecal samples. Microscopic and molecular analysis were used to detect coccidian oocysts and DNA. Several variables were analyzed for associations with coccidian DNA detection or prevalence. RESULTS Coccidian DNA was detected in 51 of 285 (17.9%) fecal samples. Of those positive samples, 1% (95% confidence interval, 0.4% to 3%) had positive results for Hammondia heydorni and none had positive results for Neospora caninum, for an estimated environmental N caninum prevalence of 0% (95% confidence interval, 0% to 7%)/1-km2 hexagonal area evaluated. Morphological classification revealed that 78.9% (225/285) of fecal samples were from coyotes and 17.2% (49/285) were from foxes. No difference in proportions of coccidian DNA-positive fecal samples was identified among canid species. Environmental temperature and fecal freshness were associated with coccidian DNA detection. Land use type, relative canid density, and cattle density were not associated with the prevalence of coccidian DNA-positive samples. CONCLUSIONS AND CLINICAL RELEVANCE The low prevalence of coccidia shed in wild canid feces in this study, including the estimated 0% environmental prevalence of N caninum, suggested that the role of the oocyst environmental phase in coccidia transmission to ruminants is likely minor in rural southeastern Ohio.

OBJECTIVE To evaluate the usefulness of injection of indocyanine green (ICG) solution with near-infrared (NIR) fluorescence imaging for transcutaneous detection of sentinel lymph nodes (SLNs) and their associated lymphatic vessels in the oral mucosa of healthy dogs. ANIMALS 6 adult purpose-bred research hounds. PROCEDURES Each dog was sedated, and 1 mL of ICG solution was injected into the gingival mucosa dorsal to the right maxillary canine tooth. Subsequently, NIR fluorescence imaging was used to transcutaneously detect the lymphatic vessels and SLNs. The distance between the injection site and each SLN was measured. Time to first evidence of node fluorescence was recorded, and velocity of ICG movement was calculated. A slide preparation of a fine-needle aspiration sample of the fluorescing structure underwent cytologic examination (to confirm presence of lymphatic tissue) and NIR fluorescence imaging (to confirm presence of ICG). RESULTS The ipsilateral mandibular lymphocentrum was the SLN in all dogs. The time to visually detectable fluorescence ranged from 4 to 15 minutes (mean ± SD, 8.8 ± 3.76 minutes). The mean velocity was 1.94 ± 0.93 cm/min. Fluorescence was not observed in the contralateral lymph nodes. Each fluorescing structure was confirmed to be lymphatic tissue, and NIR fluorescence imaging revealed that ICG was present in the sampled SLN. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that injection of ICG solution with NIR fluorescence imaging can be used to transcutaneously identify SLNs along with associated lymphatic vessels in the oral mucosa of healthy dogs. Time from injection to identification of fluorescence was rapid with prolonged retention of material within the SLN, indicating that this procedure could be performed during surgery.

OBJECTIVE To compare sedation in cockatiels (Nymphicus hollandicus) after intranasal administration of midazolam and midazolam-butorphanol. ANIMALS 9 healthy adult cockatiels. PROCEDURES A randomized, controlled, blinded, complete crossover study was conducted. Birds were assigned to 3 treatment groups. Midazolam (3 mg/kg), midazolam-butorphanol (3 mg/kg for each drug), or sterile saline (0.9% NaCl) solution (control treatment) was administered intranasally. Sedation quality was assessed at 3 time points by use of eye and body position; response to visual, auditory, and tactile stimulation; and response during manual restraint on the basis of eye position and struggling intensity. To evaluate attenuation of the manual restraint–induced stress response, heart rate, respiratory rate, and cloacal temperature were measured over a 15-minute period. Treatments were repeated after a minimum washout period of 7 days. RESULTS Median onset of first sedation effects was 85 seconds (range, 60 to 120 seconds) for midazolam and 90 seconds (range, 45 to 180 seconds) for midazolam-butorphanol. Midazolam-butorphanol resulted in significantly less vigorous struggling during restraint than did midazolam or the control treatment. Heart rate did not differ significantly among treatments. The stress-induced increase in respiratory rate was significantly attenuated by midazolam and midazolam-butorphanol, whereas the increase in cloacal temperature was not attenuated by midazolam or midazolam-butorphanol. CONCLUSIONS AND CLINICAL RELEVANCE Intranasal administration of midazolam and midazolam-butorphanol resulted in a rapid onset of sedation in cockatiels. Midazolam-butorphanol resulted in deeper sedation in both restrained and unrestrained birds than did midazolam alone. Midazolam and midazolam-butorphanol both provided safe and effective sedation in cockatiels.

OBJECTIVE To evaluate the effects of 2 fractions of inspired oxygen (Fio2s) during anesthesia on postanesthesia Pao2 and other measures of oxygen exchange. ANIMALS 22 healthy adult sexually intact female dogs undergoing ovariohysterectomy by ventral midline celiotomy. PROCEDURES Dogs were randomly assigned to receive either oxygen (Fio2 > 0.9 [100% oxygen]; n = 11; control group) or a mixture of nitrogen and oxygen (Fio2 = 0.4; 11; 40% oxygen group) as the carrier gas for isoflurane while anesthetized. All dogs were allowed to breathe spontaneously while anesthetized. For each dog, the Pao2, Paco2, other indices of oxygenation, and extent of sedation were monitored at predetermined times during and for 1 hour after anesthesia. Measured variables were compared between the 2 treatment groups and over time within each treatment group. RESULTS None of the measured variables differed significantly between the control and 40% oxygen groups at any time during the postanesthesia period. Within each treatment group, the Paco2 and extent of sedation decreased over time during the postanesthesia period. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that indices of oxygenation did not differ significantly between healthy dogs in which the Fio2 was maintained at > 0.9 and those in which the Fio2 was maintained at 0.4 while anesthetized for ovariohysterectomy. Thus, the addition of nitrogen to the carrier gas for an inhalant anesthetic conferred neither an advantage nor disadvantage in regard to oxygenation during the first hour of anesthesia recovery.

OBJECTIVE To determine the effects of grape seed extract (GSE), lutein, and fish oil containing omega-3 fatty acids on oxidative stress, migration, proliferation, and viability of lens epithelial cells (LECs). SAMPLE Lens capsules or cultured LECs obtained from canine cadavers. PROCEDURES An antioxidant reductive capacity assay was used to determine reducing capability of each substance. The LECs were cultured and incubated with various substances, including N-acetyl cysteine (NAC), when appropriate, and dimethyl sulfoxide (DMSO) as positive and vehicle control substances, respectively. A dichlorofluorescein assay was used to evaluate reactive oxygen species (ROS) production, and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to determine cell viability. Ex vivo posterior capsule opacification (PCO) was used to evaluate LEC migration and proliferation. RESULTS Antioxidant reductive effects of GSE surpassed those of NAC, lutein, and fish oil containing omega-3 fatty acids. The GSE reduced ROS production in LECs, compared with the DMSO vehicle control, whereas lutein was pro-oxidative. All test substances reduced cell viability. Ex vivo PCO was not altered by GSE, was decreased by lutein, and was increased by fish oil containing omega-3 fatty acids, compared with results for the DMSO vehicle control. CONCLUSIONS AND CLINICAL RELEVANCE Only GSE had significant antioxidant capabilities and reduced ROS production; however, no effect on ex vivo PCO was detected. Fish oil containing omega-3 fatty acids increased ex vivo PCO. No conclusions could be made regarding antioxidant effects of these substances on LECs. These findings suggested that the substances will not decrease PCO.

OBJECTIVE To describe histologic findings in the small airways during postmortem examination of actively racing horses and to quantify the degree of airway inflammation by use of a semiquantitative scoring system. SAMPLE Lung tissues obtained from 95 horses (Thoroughbreds, Standardbreds, and Quarter Horses) that had been actively racing or training. PROCEDURES 10 standardized lung sections were obtained during postmortem examination of 37 horses that had been actively racing or training, and 2 histologic sections of the caudodorsal lung lobes previously collected from each of 58 horses that died or were euthanized during racing or training were also obtained. Sections were evaluated by use of a validated histologic small airway scoring system. RESULTS Scores for inflammatory cells, smooth muscle, and hemosiderin typically were high. Signalment and cause of death were not significant predictors of lung scores. Lung sample location was a significant predictor, with the highest scores in the caudal and dorsal sections. Inflammatory cell infiltration in peribronchiolar tissues, smooth muscle hyperplasia, and hemosiderin (prevalence of 86%, 98%, and 80%, respectively) were common findings in lungs of these horses, with the caudodorsal regions more severely affected. Correlation was moderate between smooth muscle hyperplasia and inflammatory cell infltration, with minimal correlation between hemosiderin and inflammatory cell infiltration. CONCLUSIONS AND CLINICAL RELEVANCE Inflammatory airway disease has been identified by use of bronchoalveolar lavage in young athletic horses throughout the world. In the study reported here, pathological changes were detected in the wall of small airways of horses that were actively training or racing.

OBJECTIVE To identify whether age, sex, or breed is associated with crown height of the left and right maxillary first molar tooth (M1) measured on CT images, to develop a mathematical model to determine age of horses by use of M1 crown height, and to determine the correlation between M1 crown height measured on radiographic and CT images. SAMPLE CT (n = 735) and radiographic images (35) of the heads of horses. PROCEDURES Crown height of left and right M1 was digitally measured on axial CT views. Height was measured on a lateral radiographic image when available. Linear regression analysis was used to identify factors associated with crown height. Half the data set was subsequently used to generate a regression model to predict age on the basis of M1 crown height, and the other half was used to validate accuracy of the predictions. RESULTS M1 crown height decreased with increasing age, but the rate of decrease slowed with increasing age. Height also differed by sex and breed. The model most accurately reflected age of horses < 10 years old, although age was overestimated by a mean of 0.1 years. The correlation between radiographic and CT crown height of M1 was 0.91; the mean for radiographic measurements was 2.5 mm greater than for CT measurements. CONCLUSIONS AND CLINICAL RELEVANCE M1 crown height can be used to predict age of horses. Results for CT images correlated well with those for radiographic images. Studies are needed to develop a comparable model with results for radiographic images.

OBJECTIVE To assess differences in skin shrinkage between grossly visible tumor and grossly normal marginal skin of dogs for cutaneous mast cell tumors (MCTs) excised with curative intent and to determine an equation to estimate postexcisional gross tumor margins from preexcisional measurements and vice versa. SAMPLE 19 cytologically confirmed and surgically excised cutaneous MCTs obtained from dogs. PROCEDURES Tumors were measured in craniocaudal and dorsoventral directions before excision, immediately after excision, and after fixation in formalin. Both grossly visible tumor and surrounding grossly normal skin that comprised the surgical margin were measured at each time point. Percentage of shrinkage was compared among time points and between the tumor and surrounding grossly normal skin. Patient and histopathologic variables were correlated to skin shrinkage. RESULTS Overall shrinkage was 17.70%. The amount of shrinkage within the grossly visible tumor (4.45%) was less than that within the surrounding grossly normal skin (24.42%). Most of the shrinkage occurred immediately after excision. There was no effect of age, sex, completeness of excision, or degree of edema. Accuracy of an equation to estimate postexcisional margins from preexcisional measurements was only 18.4%. CONCLUSIONS AND CLINICAL RELEVANCE Grossly evident MCTs of dogs shrunk less than did the grossly normal surrounding skin. Although an equation to estimate postexcisional margins from preexcisional measurements could be derived, it likely would need to contain additional variables not included in the study reported here. Until such an equation exists, care must be used when extrapolating surgical margins from histologic margins and vice versa.

OBJECTIVE To compare the leak pressure and amount of time required to perform closure for 2 double-layer esophagotomy closure techniques. SAMPLE 28 intrathoracic esophageal segments harvested from 38 porcine cadavers. PROCEDURES Longitudinal 3-cm esophagotomy incisions made in porcine cadaveric esophagi were closed with 2 double-layer closure techniques. Fifteen incisions were closed with a simple interrupted pattern, and 13 incisions were closed with a simple continuous pattern. Leak pressure, bursting wall tension, and closure time were compared between suture patterns by use of a t test or Mann-Whitney rank sum test. RESULTS Median leak pressures differed significantly between segments closed with the simple interrupted pattern (16.0 mm Hg; range, 5.4 to 54.9 mm Hg) and the simple continuous pattern (38.7 mm Hg; range, 11.3 to 81.9 mm Hg). Median bursting wall tension differed significantly between the simple interrupted pattern (0.63 × 10(5) dynes/cm; range, 0.16 × 10(5) dynes/cm to 2.89 × 10(5) dynes/cm) and the simple continuous pattern (1.79 × 10(5) dynes/cm; range, 0.44 × 105 dynes/cm to 4.70 × 10(5) dynes/cm). Mean ± SD closure time differed significantly between the simple interrupted pattern (19.2 ± 2.0 minutes) and the simple continuous pattern (14.7 ± 1.5 minutes). CONCLUSIONS AND CLINICAL RELEVANCE In the study reported here, double-layer simple continuous closure resulted in a higher median postoperative leak pressure and higher median postoperative bursting wall tension and could be performed more rapidly than the double-layer simple interrupted closure on these porcine cadaveric specimens.

OBJECTIVE To determine the minimum alveolar concentration of desflurane (MACDES) and effects on cardiovascular variables in positive-pressure ventilated sheep. ANIMALS 13 adult female sheep. PROCEDURES Anesthesia was induced with desflurane. After a 30-minute equilibration at an end-tidal concentration of desflurane (etDES) of 10.5%, an electrical stimulus (5 Hz/ms and 50 mA) was applied for 1 minute or until gross purposeful movement occurred. The etDES was then changed by 0.5% (modified up-down method), depending on whether a positive motor response had been elicited, and stimulation was repeated. The MACDES was the etDES midway between a positive and negative response. After MACDES was determined, etDES was increased to 1.3 and 1.6 MACDES. Animals were allowed to equilibrate for 15 minutes, and cardiovascular, blood gas, acid-base, and hematologic variables were measured. Times to induction of anesthesia, extubation, attainment of sternal position, and standing and duration of anesthesia were recorded. RESULTS Mean ± SD MACDES was 9.81 ± 0.79%. Times to intubation, extubation, and standing were 4.81 ± 2.21 minutes, 14.09 ± 4.05 minutes, and 32.4 ± 12.5 minutes, respectively. Duration of anesthesia was 226 ± 22 minutes. Heart rate increased significantly at induction of anesthesia but otherwise remained at preanesthetic rates. Arterial blood pressures progressively decreased with increasing etDES; pressures increased slightly only in response to noxious stimulation. CONCLUSIONS AND CLINICAL RELEVANCE The MACDES determined here compared favorably with that determined for other sheep populations and indicated similar anesthetic potency as in other species. Desflurane caused dose-dependent arterial hypotension, which indicated the need for careful blood pressure monitoring.