bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence, vasculature, and innervation of myocardial bridges in dogs
Authors: Tangkawattana P. , Muto M. , Nakayama T. , Karkoura A. , Yamano S. , Yamaguchi M. 
Published: January 2024

SUMMARY

Objective
To report gross anatomic examination of the canine myocardial bridge (MB), a muscular band found above the coronary artery (CA), with respect to its occurrence, location, vascularization, and innervation.

Sample Population
629 canine hearts obtained within 1 to 3 hours after euthanasia.

Procedure
After an incision was made at the left fifth intercostal space, the pericardial sac was cut open, and if an MB was present, the heart, lungs, and annexed structures were removed together and subsequently subjected to macroscopic examination of MB musculature and innervation after formalin fixation. Vascular casting was performed by use of methyl methacrylate perfusion.

Results
Of the 629 canine hearts examined, 189 (30%) had MB, occurrence of which was independent of sex, age, and breed. Among 13 MB-containing specimens examined in detail, there was great variation in thickness (0.11 to 2.24 mm; mean, 0.45 mm) of MB and distance (24 to 236 μm; mean, 103 μm) between the MB and the paraconal interventricular branch of the left CA (PIBL). One pair or 2 pairs of blood vessels from the PIBL supplied the MB muscle. Venous blood returned to the coronary circulation via the branches of the great coronary vein coursing on both sides of the PIBL, in close contact with the PIBL and the groove wall. The 2 veins rejoined at the upper portion of the PIBL and passed obliquely to the coronary groove under the left auricle, and finally drained the blood through the coronary sinus into the right ventricle. Innervation to the MB muscle was derived from nerve branches of the middle cervical ganglion and left vagus nerve.

Conclusion
Prevalence and localization of MB in dogs and human beings are similar. Vascularization of the MB muscle originates from the PIBL. The cervical ganglion and vagus nerve control the MB muscle. (Am J Vet Res 1997;58:1209–1215)
Cardiovascular effects of equipotent isoflurane and alfentanil/isoflurane minimum alveolar concentration multiple in cats
Authors: Pascoe Peter J. , Ilkiw Jan E. , Fisher Linda D. 
Published: January 2024

SUMMARY

Objective
To determine whether administration of opioids to anesthetized cats induced less cardiovascular depression than that induced by an equivalent amount of anesthetic alone, and to measure endocrine responses to a noxious stimulus.

Animals
6 healthy female cats.

Procedure
Anesthesia was induced with isoflurane and was maintained for 60 minutes at 1.3 isoflurane MAC. Blood gas tensions, pH, and plasma alfentanil and hormone concentrations, blood pressures, and cardiac output were measured. A noxious stimulus was applied for 5 minutes, while blood acquisition and measurements were repeated. Alfentanil was administered IV to achieve estimated plasma concentration of 500 ng/ml, and end-tidal isoflurane concentration was reduced by 35%. After another 60 minutes, blood was obtained and measurements were taken, then a second 5-minute noxious stimulus was applied while blood acquisition and measurements were retaken.

Results
Alfentanil administration and reduction of isoflurane concentration significantly increased body temperature, heart rate, mean arterial pressure, mean pulmonary arterial pressure, stroke index, cardiac index, hemoglobin, oxygen delivery index, Pvo2 and Pvco2, dopamine, epinephrine (EPI), norepinephrine (NOREPI), and cortisol values, and significantly decreased arterial and venous pH. Application of a noxious stimulus significantly increased heart rate, stroke index, cardiac index, Pao2, oxygen delivery index, arterial and venous pH, and NOREPI values, and decreased bicarbonate, Paco2, Pvco2, and EPI values. Alfentanil administration blunted cardiac index, Paco2, oxygen delivery index, arterial pH, Pao2, and EPI, and NOREPI responses to a noxious stimulus.

Conclusions
Compared with isoflurane alone, alfentanil administration and reduction of isoflurane MAC improved cardiovascular variables, and blunted respiratory, hormonal, and most hemodynamic responses to a noxious stimulus in cats.

Clinical Relevance
Use of the balanced opioid anesthesia regimen induced some beneficial effects in healthy cats; effects were similar to, although greater in nature, than effects induced by a noxious stimulus. (Am J Vet Res 1997;58:1267–1273)
Noninvasive monitoring of fetal heart rate during the last ten days of gestation in sows
Authors: Cohen S. , Mulder E. J. H. , van Oord H. A. , Jonker F. H. , van der Weijden G. C. , Taverne M. A. M. 
Published: January 2024

SUMMARY

Objective
To develop and evaluate a noninvasive technique for monitoring and analyzing porcine fetal heart rate (FHR) during late gestation.

Animals
8 fetuses of 8 pluriparous sows in late gestation.

Procedure
With the sow positioned in lateral recumbency, the most caudal fetus was identified, using real time ultrasonography, and its heart rate was recorded for 60 minutes by use of Doppler cardiography. The same fetus was identified and monitored repeatedly during the last 10 days of gestation, excluding the 24 hours before delivery. Visual inspection and computerized analysis of the recordings were performed.

Results
66 one-hour recordings were obtained from 8 fetuses, 1 in each of 8 sows. Mean signal loss was 37.5%. Episodes of low FHR and low FHR variation (FHR pattern A) alternated with episodes of high FHR and high FHR variation (FHR pattern B). This cyclic alternation between 2 distinct FHR patterns was observed in 46 of 66 (69.7%) recordings, and suggests the presence of different behavioral states in fetal pigs. Basal FHR decreased toward parturition in 7 fetuses, but increased in 1 fetus with abdominal ascites. Basal FHR and long-term FHR variation were negatively correlated (r[S) = −0.73; P < 0.001).

Conclusion
Noninvasive monitoring of FHR is possible and feasible during late gestation in pigs. This method permits longitudinal studies under pathophysiologic conditions and the evaluation of the effects of endogenous and exogenous influences on porcine FHR. (Am J Vet Res 1997;58:1285–1290)
Effect of pentoxifylline, flunixin meglumine, and their combination on a model of endotoxemia in horses
Authors: Baskett Anne , Barton Michelle Henry , Norton Natalie , Anders Brendan , Moore James N. 
Published: January 2024

SUMMARY

Objective
To compare effects of a single dose of pentoxifylline (PTX), flunixin meglumine (FM), and their combination (FM/PTX) in a model of equine endotoxemia.

Animals
24 healthy horses, aged 2 to 15 years.

Procedure
4 groups (n = 6/group) received 30 ng of Escherichia coli O55:B5 endotoxin/kg of body weight, IV, over 30 minutes, and 1 of the following preparations 15 minutes before and 8 hours after endotoxin infusion: FM, 1.1 mg/kg; PTX, 8 mg/kg; FM/PTX, 1.1 mg of FM and 8 mg of PTX/kg; and saline solution bolus (ENDO). Clinical and hematologic variables were measured over 24 hours.

Results
Compared with ENDO, FM given before endotoxin significantly reduced TxB2, and 6-keto-PGF1 concentrations, pulse, rectal temperature, and attitude score. Pentoxifylline given before endotoxin resulted in significantly higher 6-keto-PGF1 concentration at 1.5 hours and significantly lower PAI-1 activity at 12 hours. Tumor necrosis factor and IL-6 activities in horses given PTX alone were not significantly different from values in those given the saline bolus. FM/PTX induced effects similar to those of FM alone on endotoxin-induced changes in temperature and TxB2 concentration, and 6-keto-PGF1 concentration was significantly lower than that in horses of the ENDO group at 1 hour. In horses of the FM group, 6-keto-PGF1 concentration was significantly lower than that in horses of the ENDO group, from 0.5 hour to 2 hours. Horses of the FM and FM/PTX groups had significantly higher IL-6 activity at 1.5 and 2 hours than did horses of the PTX and ENDO groups; those of the FM and FM/PTX groups had significantly lower WBC count than did those of the PTX and ENDO groups.

Conclusions
FM/PTX may help offset deleterious hemodynamic effects of endotoxin more effectively than does either FM or PTX alone. (Am J Vet Res 1997;58:1291–1299)
Effects of pentoxifylline infusion on response of horses to in vivo challenge exposure with endotoxin
Authors: Barton Michelle Henry , Moore James N. , Norton Natalie 
Published: January 2024

SUMMARY

Objective
To evaluate the effect of pentoxifylline on response of horses to in vivo challenge exposure with endotoxin.

Animals
24 healthy horses in 3 treatment groups: pentoxifylline, endotoxin, or endotoxin and pentoxifylline.

Procedure
Horses of the pentoxifylline group were given a bolus of pentoxifylline (7.5 mg/kg of body weight, IV), followed by an infusion (3 mg/kg/h) over 3 hours, and those of the endotoxin group were given 20 ng of endotoxin/kg IV over 30 minutes. Those of the combination group were given both of the aforementioned compounds; pentoxifylline was administered immediately after endotoxin. Clinical (rectal temperature, heart and respiratory rates, blood pressure) and hematologic (WBC count; whole blood recalcification time; plasma fibrinogen, thromboxane B2, and 6-keto-prostaglandin F1α, concentrations; plasma plasminogen activator inhibitor activity; and serum tumor necrosis factor and interleukin 6 activities) variables were evaluated over 24 hours.

Results
Compared with baseline values, there were no significant changes in any variable over time in the horses receiving only pentoxifylline, with the exception of a significant increase in WBC count. Rectal temperature, heart rate, mean blood pressure, WBC count, whole blood recalcification time, fibrinogen concentration, plasminogen activator inhibitor activity, tumor necrosis factor and interleukin 6 activities, and plasma thromboxane B2 concentration changed significantly over time in horses of the endotoxin and endotoxin-pentoxifylline combination groups. Respiratory rate and plasma 6-keto-prostaglandin F1α concentration changed significantly over time only in horses of the endotoxin group. Compared with values for the endotoxin group, rectal temperature and respiratory rate were significantly lower, and whole blood recalcification time was longer for the endotoxin/pentoxifylline group.

Conclusion
Beneficial effects of pentoxifylline are limited when it is administered IV to horses after in vivo challenge exposure with endotoxin. (Am J Vet Res 1997;58:1300–1307)
In vitro flow characteristics of the Ahmed and self-constructed anterior chamber shunts
Authors: Strubbe D. Todd , Gelatt Kirk N. , MacKay Edward O. 
Published: January 2024

SUMMARY

Objective
To compare in vitro opening pressures (OP) and closing pressures (CP) of the Ahmed VS-1 and VS-2 glaucoma valves with those of several selfconstructed valve ‘prototypes,’ and to assess their ability to maintain perfusion pressures between 6 and 21 mm of Hg.

Sample Population
Ahmed VS-1 (n = 6), 2 groups of Ahmed VS-2 (group 1: n = 12; group 2: n = 14), and self-constructed valves with linear incisions in the long axis of the tube wall (n = 6) or X-shaped incisions in the tube walls (n = 2).

Procedure
Valves were perfused with deionized water, lactated Ringer's solution (LRS), Dulbecco's modified Eagle's medium (DMEM), DMEM plus 50% equine serum (ES), and 100% ES. Flow rates of 2.85, 4.2, 6.0, 9.0, and 12.0 μl/min were used for each perfusate. Valves were tested 3 times for reproducibility, and OP/CP were compared for each system.

Results
OP/CP of the VS-1, VS-2 (group 1), VS-2 (group 2), and linear 1.0-cm incisional valves with thick tubing consistently increased with increasing perfusion rate. Linear 0.5-cm (thick tubing) and 1.0-cm (thin tubing) incisional valves had increasing OP/CP with increasing perfusion rate in all but a few instances. Mean OP/CP decreased with increasing perfusate osmolarity for all perfusates except LRS, using the VS-1 and V-2 (group 2) valves. Mean OP/CP were consistently lower for VS-1 than VS-2 (group 1) valves at any given flow rate and for any given perfusate. Mean OP/CP were consistently lower for VS-2 (group 1) than VS-2 (group 2) valves at any given flow rate and for any given perfusate. The linear 0.5-cm incisional valves with thick and thin tubing induced the highest mean OP/CP, maximizing at > 30 mm of Hg.

Conclusions
Only the VS-2 (group 2) valves consistently had mean OP/CP between 6 and 21 mm of Hg for all perfusates and at all flow rates.

Clinical Relevance
Anterior chamber shunts, although imperfect, appear to offer a physiologically sound alternative for glaucoma management. (Am J Vet Res 1997;58:1332–1337)
Accuracy of localizing radiopaque markers by abdominal radiography and correlation between their gastric emptying rate and that of a canned food in dogs
Authors: Guilford W. Grant , Lawoko Charles R. O. , Allan Frazer J. 
Published: January 2024

SUMMARY

Objectives
To determine accuracy of abdominal radiography in locating radiopaque markers in the gastrointestinal tract and to assess correlation between gastric emptying rate of radiopaque markers and that of canned food.

Animals
17 healthy dogs.

Procedure
Dogs were fed thirty 1.5-mm markers and ten 5-mm markers mixed in sufficient food to meet 25% of their daily caloric intake. They were then euthanatized by administration of an overdose of barbiturate at 1, 2, 5, 8, or 12 hours after eating and the abdomen was radiographed. The stomach, small intestine, and large intestine were then separated and radiographed in isolation. The wet and dry weights of the stomach contents were determined. The apparent and actual locations of the markers and the gastric emptying rates of markers, wet matter, and dry matter were compared, using rank correlation.

Results
All comparisons indicated significant (P < 0.025), high correlation coefficients (> 0.92). The mean difference between the apparent and actual locations of the markers was < 3% for all comparisons. The mean difference between the percentage of small markers and large markers retained in the stomach and that of dry matter was 7.8 (SD, 6.2; range, 0 to 18)% and 11.9 (SD, 12.5; range, 0 to 44)%, respectively.

Conclusions
The gastric emptying and orocolic transit rates of the markers were accurately predicted by abdominal radiography. The gastric emptying rate of the diet and the small markers and, to a lesser extent, the large markers was closely correlated.

Clinical Relevance
When fed with a special canned food diet, radiopaque markers can be used to assess the gastric emptying rate of food with sufficient accuracy for clinical purposes. (Am J Vet Res 1997;58:1359–1363)
Rehabilitation of dogs with surgically treated cranial cruciate ligament-deficient stifles by use of electrical stimulation of muscles
Authors: Johnson J. M. , Johnson A. L. , Pijanowski G. J. , Kneller S. K. , Schaeffer D. J. , Eurell J. A. , Smith C. W. , Swan K. S. 
Published: January 2024

SUMMARY

Objective
To determine effect of electrical muscle stimulation (EMS) on rate and degree of return to function of the limb and development of degenerative joint disease (DJD) after surgical creation and subsequent stabilization of the cranial cruciate ligament (CrCL)-deficient stifle.

Animals
12 clinically normal adult large (19.5 to 31.5 kg) dogs.

Procedure
Dogs were anesthetized, and the right CrCL was severed via arthrotomy, destabilizing the stifle. After 3 weeks, the stifle was surgically stabilized. Three weeks later, 6 dogs were subjected to an EMS treatment protocol for the thigh muscles. At 5, 9, 13, and 19 weeks after stifle destabilization, treated (n = 6) and control (n = 6) dogs were evaluated for return of stifle function. Gross and histologic evaluations of the stifles were performed at 19 weeks after stifle destabilization.

Results
Treated dogs had significantly (P = 0.001) better lameness score than did control dogs. There was less palpable crepitation of the stifle in treated dogs (P = 0.06); treated dogs also had significantly (P = 0.01) fewer radiographic signs of bone changes. Thigh circumference was significantly (P = 0.02) larger in treated dogs.There was less gross cartilage damage (P = 0.07) in the EMS-treated dogs, but more medial meniscal damage (P = 0.058, cranial pole; P = 0.051, caudal pole).

Conclusions
Improved lameness scores, larger thigh circumference, and decreased radiographically apparent bony changes observed for the treated group of dogs support the hypothesis that dogs treated by EMS after surgical stabilization of the CrCL-deficient stifle had improved limb function, with less DJD, than did dogs treated with the currently accepted clinical protocol of cage rest and slow return to normal activity. However, results of force plate evaluation did not support the hypothesis. Increased meniscal damage in dogs treated by EMS may be cause for concern. (Am J Vet Res 1997;58:1473–1478)
Antimicrobial susceptibility of Fusobacterium necrophorum isolated from bovine hepatic abscesses
Authors: Lechtenberg K. F. , Nagaraja T. G. , Chengappa M. M. 
Published: January 2024

SUMMARY

Objective
To determine the resistance and susceptibility to antimicrobial compounds of Fusobacterium necrophorum isolates from bovine hepatic abscesses.

Procedure
37 isolates of F necrophorum (21 subsp necrophorum and 16 subsp funduliforme) isolated from bovine hepatic abscesses were obtained from cultures grown and maintained in anaerobic brain heart infusion broth. A broth dilution method was used as an initial screening to determine general susceptibility to 31 antimicrobial compounds. The minimal inhibitory concentrations (MIC) of 19 of the antimicrobial compounds that inhibited growth in the initial test were determined by use of the broth microdilution method.

Results
Fusobacterium necrophorum isolates were generally susceptible to penicillins, tetracyclines (chlortetracycline and oxytetracycline), lincosamides (clindamycin and lincomycin), and macrolides (tylosin and erythromycin), and were resistant to aminoglycosides (kanamycin, neomycin, gentamicin, and streptomycin), ionophores (except narasin), and peptides (avoparcin, polymyxin, and thiopeptin). The 5 antimicrobials (bacitracin, chlortetracycline, oxytetracycline, tylosin, and virginiamycin) that have FDA approval for prevention of liver abscesses in feedlot cattle were inhibitory to F necrophorum. Differences in antimicrobial susceptibility patterns were observed between the 2 subspecies only for clindamycin and lincomycin. The MIC of F necrophorum isolates from antibiotic-fed cattle were similar to those for isolates from nonantibiotic-fed cattle.

Conclusions
The MIC of FDA-approved antibiotics were not reflective of the efficacy of antibiotics in preventing liver abscesses in feedlot cattle. Also, continuous feeding of tylosin did not appear to select resistant F necrophorum. (Am J Vet Res 1998;59:44–47)
Assessment of the bacterial flora of the proximal part of the small intestine in healthy cats, and the effect of sample collection method
Authors: Papasouliotis K. , Sparkes A. H. , Werrett G. , Egan K. , Gruffydd-Jones E. A. , Gruffydd-Jones T. J. 
Published: January 2024

SUMMARY

Objective
To investigate the bacterial flora of the proximal part of the small intestine of healthy cats and determine the effect of sample collection method on results of bacteriologic culture.

Animals
25 healthy barrier-maintained specific-pathogen-free-derived cats.

Procedure
Aspirated, undiluted samples of proximal small intestinal juice were obtained via oral endoscopy (UEA), and a second sample was collected after instillation of 1 ml of sterile saline solution (diluted, DEA). Undiluted juice also was obtained by direct needle aspiration (NA) from the intestinal lumen. Samples for quantitative and semiqualitative bacteriologic examination were grown aerobically and anaerobically.

Results
Mean (range) log10 colony-forming units of total bacteria/ml were 6.2 (2.0 to 8.3) for NA, 6.0 (2.0 to 7.9) for UEA, and 4.9 (2.0 to 7.5) for DEA samples. One cat had no growth (≤ 2.0 colony-forming units/ml) for samples obtained using all 3 methods, and another cat had no growth for the DEA sample only. Mean total aerobic, anaerobic, and bacterial counts were not significantly different between NA and UEA methods, but these techniques yielded significantly higher mean counts than did DEA samples (P ≤ 0.002, ANOVA). As a percentage of the total bacteria isolated, anaerobes constituted a median 35, 32, and 50% of the NA, UEA, and DEA samples, respectively. Good correlation was found between the NA and UEA samples for total bacteria, aerobes, and anaerobes (r ≥ 0.830).

Conclusions
Compared with human beings, healthy cats carry high numbers of bacteria in the proximal part of the small intestine. By comparison with NA samples, UEA samples accurately reflected bacterial populations in the small intestine, whereas DEA samples significantly underestimated these populations. (Am J Vet Res 1998;59:48–51)
Efficacy of eprinomectin against Hypoderma spp in cattle
Authors: Holste J. E. , Colwell D. D. , Kumar R. , Lloyd J. E. , Pinkall N. P. M. , Sierra M. A. , Waggoner J. W. , Langholff W. K. , Barrick R. A. , Eagleson J. S. 
Published: January 2024

SUMMARY

Objective
To determine the efficacy of a topical formulation of eprinomectin against natural infestations of first (L1)-stage, and second and third (L2/L3)-stage larvae of Hypoderma spp.

Animals
140 approximately 6- to 18-month-old cattle of various breeds.

Procedure
Cattle, selected from herds with high prevalence of Hypoderma infestation, were treated in 4 experiments: within each replicate, 1 animal received eprinomectin at a dosage of 500 μg/kg of body weight against first-stage larvae (L1). The second animal received the same treatment against second or third-stage larvae (L2/L3). The third animal served as an untreated control. In a fifth experiment, visible warbles were treated on half of the cattle. Remaining cattle served as vehicle-treated controls. In 1 experiment, warbles were examined from time of treatment until all lesions were resolved. In 4 experiments, emerging Hypoderma larvae were recovered, speciated, and enumerated, and viability was determined.

Results
Eprinomectin (500 μg/kg) efficacy was complete against L1. Hypoderma L2/L3 eradication approached 100% efficacy (1 live larva was recorded). Warbles in treated cattle resolved in a significantly shorter time than did those in controls. Adverse reactions related to treatment were not observed in any of the trials.

Conclusions
Eprinomectin (500 μg/kg) applied topically was safe and highly efficacious for treatment of all larval stages of Hypoderma spp in these trials.

Clinical Relevance
Attributes of eprinomectin besides antiparasite efficacy allow treatment of all classes of cattle with no need for meat or milk withdrawal. (Am J Vet Res 1998;59:56–58)