bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacokinetics of gentamicin in laboratory rabbits
Authors: Curl James L. , Curl Joan S. 
Published: February 2025

SUMMARY
The pharmacokinetics of gentamicin was studied in 5 healthy adult laboratory rabbits of both sexes. Gentamicin sulfate (5% aqueous solution) was administered rapidly (iv) at a dosage of 3 mg/kg of body weight. Venous blood samples were taken at 0 (baseline), 5, 10, 15, and 30 minutes, and 1, 1.5, 2, 2.5, 3, 4, 5, and 6 hours after gentamicin administration. Serum gentamicin concentration was measured by radioimmunoassay. With the aid of a nonlinear least-squares program, the gentamicin concentration data were found to be best described by a 2-compartment model, with r2 = 0.989. Half-life, as determined from the terminal phase, was 56.6 ± 2.4 (mean ± sd) minutes. Calculation of total body clearance provided a mean of 1.69 ± 0.07 ml/min/kg of body weight. Volume of distribution, calculated from the area under the curve for each animal, was 0.138 ± 0.005 L/kg.
Morphologic and morphometric studies of the intrinsic laryngeal muscles in clinically normal adult dogs
Authors: Braund Kyle G. , Steiss Janet E. , Marshall Arvle E. , Mehta Jagjivan R. , Amling Karen A. 
Published: February 2025

SUMMARY
To establish normal histologic and histochemical data and to determine reference values for fiber type proportions (percentages, mean fiber diameters, atrophy and hypertrophy factors, and variability coefficients), a histochemical study was carried out on intrinsic muscles of the larynx (cricothyroid, cricoarytenoid lateralis, cricoarytenoid dorsalis, and thyroarytenoid muscles) of clinically normal dogs. Using myosin adenosine triphosphatase stain under acidic preincubation (pH 4.3) conditions, 3 histochemical fiber types—1, 2A, and 2C—were recognized. The percentage of type-2C fibers varied from 1 to 2% in thyroarytenoid muscles to approximately 10% in cricoarytenoid lateralis muscles. There was no significant difference in mean diameter between left- and right-side specimens of each muscle for type 1 vs type 2. The largest fibers (mean ± sd) of both types were observed in the cricothyroid muscles (type 1, 38.19 ± 7.76 μm; type 2, 43.25 ± 8.66 μm), and the smallest fibers were found in the thyroarytenoid muscles (type 1, 29.38 ± 5.12 μm; type 2, 33.84 ± 6.20 μm). Respective mean diameters of fiber types from cricoarytenoid dorsalis (type 1, 32.05 ± 5.69 μm; type 2, 38.95 ± 7.75 μm) and cricoarytenoid lateralis (type 1, 33.75 ± 5.98 μm; type 2, 37.09 ± 7.01 μm) muscles were similar. The histographic distribution of fiber type diameters was unimodal in all muscles. In each muscle, the mean fiber diameter of type-2 fibers was greater than that of type-1 fibers. Each muscle had a type-2 fiber predominance of variable degrees: cricothyroid and cricoarytenoid dorsalis muscles each had a mean type-1 to type-2 ratio of 40:60, whereas a pronounced type-2 fiber predominance was found in the cricoarytenoid lateralis (15:85) and thyroarytenoid (5:95) muscles. The number of fibers with internal nuclei never exceeded 1%, atrophy and hypertrophy factors typically were < 150, and variability coefficients were uniformly < 250. Muscle spindles were not observed in 40 intrinsic laryngeal muscle specimens.
Effect of phenytoin on the clinical signs and in vitro muscle twitch characteristics in horses with chronic intermittent rhabdomyolysis and myotonia
Authors: Beech J. , Fletcher J. E. , Lizzo F. , Johnston J. 
Published: February 2025

SUMMARY
In vitro twitch characteristics of the semimembranosus muscle were evaluated in 9 clinically normal horses, in 15 horses with chronic intermittent rhabdomyolysis (cir) and in 2 horses with myotonia. Effects of phenytoin on in vitro muscle twitch and clinical signs of cie and myotonia were evaluated in these same horses.
Times to 90% relaxation were prolonged in the horses with cir (mean ± sem, 186 ± 5.9 ms) and in 2 horses with myotonia (197 and 177 ms) compared with those in clinically normal horses (mean ± sem, 146 ±2.1 ms). Horses with cir also had significantly (P < 0.05) longer times to 50% relaxation, compared with clinically normal horses. In the group of horses with cir, Standardbreds had significantly (P < 0.05) longer times to 90% and 50% relaxation, compared with Thoroughbreds. Times to 100% peak tension did not differ among the groups. Administration of phenytoin directly into a muscle preparation bath solution had no effect on muscle twitch properties. After the initial muscle biopsy, phenytoin was administered orally for 7 to 10 days to 4 horses with cir, 2 myotonic horses, and 2 clinically normal horses before repeat biopsy from the same site in the contralateral semimembranosus muscle. Times to 90% relaxation decreased from 197 and 177 ms to 144 and 126 ms, respectively, in the 2 myotonic horses, from a mean of 192 (± 9) ms to 170 (± 9) ms in the 4 horses with cir and remained unchanged (154 and 140 ms before vs 155 and 139 ms after treatment) in the 2 clinically normal horses.
Phenytoin treatment of 8 horses with cir was associated with excellent clinical response in 7; 1 horse became lame, which prevented evaluation of the drug, and the other horse with normal muscle twitch properties continued to have seasonally severe cir. Of the 9 horses with cir that were not treated, 4 were lost to evaluation, 3 continued to be affected (but 1 of these often performed well), and 3 were reported to perform satisfactorily. After 10 days of treatment, the 2 myotonic horses had no change in gait or myotonic dimpling and myotonic discharges persisted, although subjectively, they were slightly decreased. Phenytoin appears to be useful clinically for treating horses with cir.
Effects of T-2 mycotoxin on tumor susceptibility in mice
Authors: Corrier Donald E. , Norman James O. 
Published: February 2025

SUMMARY
The effect of Fusarium-produced T-2 toxin on tumor growth was evaluated in ICR, CFW, and C57B6/6 mice inoculated with murine sarcoma, Ehrlich ascites carcinoma, or B16F1 melanoma tumor cell lines. Mice were given T-2 toxin intragastrically either at the rate of 2 mg of toxin/kg of body weight daily for 5 days or a single dosage of 4 mg of toxin/kg and were inoculated sc with tumor cells 1 or 2 days after administration of toxin. Tumor growth was assessed 15 to 41 days after tumor challenge by determining the frequency of tumor development and tumor weights. Significant increases in the frequency of development of murine sarcoma (P < 0.005), Ehrlich ascites carcinoma (P < 0.01), and B16F1 melanoma tumors (P < 0.05) were detected in toxin-treated mice, compared with control mice. Murine sarcoma and B16F1 melanoma tumor weights also were significantly (P < 0.01) higher in toxin-treated mice. The effect of T-2 toxin on tumor growth was more marked after 5 daily treatments than after a single dose.
Efficacy of ivermectin in oral drench and paste formulation against migrating larvae of experimentally inoculated Parascaris equorum
Authors: French Dennis D. , Klei T. R. , Taylor H. W. , Chapman M. R. 
Published: February 2025

SUMMARY
Twenty-one mixed-breed pony foals, reared and maintained under parasite-free conditions, were used to test the efficacy of ivermectin in oral drench and paste formulations (200 μg/kg) against 11-day-old migrating larvae of Parascaris equorum. Three replicates of 4 foals and 3 replicates of 3 foals were formed on the basis of age. Foals in replicates of 4 were randomly allocated to be indicators, or to receive vehicle (control) or ivermectin paste or ivermectin liquid. Foals in replicates of 3 were randomly allocated to receive vehicle or ivermectin paste or ivermectin liquid.
The recovery of larvae from the lungs, liver, and small, intestines of the indicator foals showed that 99.9% of the larvae were in the lungs 11 days after inoculation (day 0 of treatment). The recoveries of larvae from lungs and small intestines of controls at 25 days after inoculation indicated that all larvae had migrated to the small intestine by this time. The mean length of larvae recovered from the lungs (11 days after inoculation) was 0.87 mm; the mean length of those recovered from the small intestine (25 days after inoculation) was 3.65 mm. Using larvae recovered from small intestinal contents for calculations, ivermectin in both formulations was 100% effective against 11-day P equorum (P < 0.01, compared with control group geometric mean of 1498.4).
Tropism of canine neutrophils to xanthine oxidase
Authors: Gruber Dale F. , Farese Ann M. 
Published: February 2025

SUMMARY
Quantitative evaluation of neutrophil chemotaxis was performed on cells obtained by hypotonic-lysis techniques from heparinized blood samples from clinically normal dogs. The techniques resulted in neutrophil recovery rates between 60 and 80%. Chemotaxis comparisons were based on cellular migration in microchambers equipped with polycarbonate membranes with 5-μm pores. Chemoattractant comparisons were based on neutrophil migration to medium, normal canine plasma, zymosan-activated plasma, and xanthine oxidase. Cellular migration to zymosan-activated plasma in buffer (1:100 dilution) was significantly (P < 0.001) enhanced over random baseline medium migration. Neutrophil migrations to normal canine plasma and xanthine oxidase were quantitatively less than to zymosan-activated plasma, but were equivalent to each other and significantly greater than for random migration. Migration to xanthine oxidase was maximal at concentrations near 1 U/ml within 30 minutes.
Serum and tissue concentrations of erythromycin in calves with induced pneumonic pasteurellosis
Authors: Burrows G. E. , Gentry M. , Ewing P. 
Published: February 2025

SUMMARY
The effects of pneumonia on the pharmacokinetics of erythromycin administered im and the tissue concentration changes with time were evaluated in 2-month-old calves. Pneumonia was induced by injection of Pasteurella haemolytica cultures through the thoracic wall into each lung. Six days prior to induction of pneumonia, erythromycin (15 mg/kg) was administered in a single im dose. Erythromycin was administered again 48, 72, and 96 hours after injection of P haemolytica. On the third day of erythromycin administration (96 hours), the calves were serially euthanatized in groups of 4 calves each at 2, 5, 8, 12, 18, and 24 hours after the final dose was given. Tissue concentrations of erythromycin in kidney, liver, lung, muscle, csf, and serum were determined. Neither the serum concentrations nor the overall pharmacokinetic values were significantly (P ≤ 0.05) changed by pneumonia. The concentrations of erythromycin were maximal at 5 hours for liver, muscle, and serum and at 8 hours for csf, kidney, and lung. Serum and muscle concentrations were similar, whereas concentrations in csf were lower than in serum and higher in kidney, liver, and lung. The lung/serum ratios were approximately 2.5 to 3 at 8 through 24 hours after im administration. The peak concentration in lung was approximately 6 μg/g at 8 hours.
Prevalence of antibodies to alcelaphine herpesvirus-1 and nucleic acid hybridization analysis of viruses isolated from captive exotic ruminants
Authors: Seal Bruce S. , Heuschele Werner P. , Klieforth Robert B. 
Published: February 2025

SUMMARY
A serologic survey was conducted to determine the prevalence of antibodies to alcelaphine herpesvirus-1 (ahv-l) in captive exotic ruminants within the United States. Forty-six percent of the members of the subfamily Alcelaphinae (wildebeest, topi, hartebeest) in the family Bovidae had virus-neutralizing antibody to ahv-1. Other subfamilies of Bovidae with high prevalence of virus-neutralizing antibodies to ahv-1 included Hippotraginae (oryx and addax) and Caprinae (sheep and goats), with prevalence of 45% and 29%, respectively. Herpesviruses that have been isolated from captive exotic ruminant species, including healthy animals and those with clinical malignant catarrhal fever at the Oklahoma City Zoo and the San Diego Zoo/Wild Animal Park, were analyzed by dna restriction enzyme analysis and blot hybridization. Variation has been detected among the genomes of several malignant catarrhal fever virus isolates obtained from various exotic species of ruminants, using the dna restriction enzymes BamHI and HindIII. The dna of these virus isolates is distinct from that of bovine herpesviruses 1, 2, and 4, as demonstrated by restriction enzyme analysis and nucleic acid hybridization. On the basis of restriction enzyme analysis and nucleic acid hybridization data, the dna from each of the putative alcelaphine herpesvirus isolates examined, except for the topi virus isolate, had a high degree of dna sequence similarity with the original ahv-1 isolate, wc-11, from a blue wildebeest.
Leptospirosis in Lambs
Authors: Davidson Jeffrey N. , Hirsh Dwight C. 
Published: February 2025

SUMMARY
Two major episodes of acute hemolytic disease in lambs were associated with high mortality. Clinical signs were severe depression, dyspnea, and tachycardia. Gross postmortem findings included hemoglobinuria and icterus. Histologic examination revealed tubular necrosis and periacinar hepatocellular necrosis. Leptospira interrogans serotype pomona was proposed as the causative agent because high serum antibody titers for this bacterium were found in lambs and ewes in the affected flocks.
Endocarditis Caused by Erysipelothrix rhusiopathiae in a Dog
Authors: Hoenig Margarethe , Gillette Deborah M. 
Published: February 2025

SUMMARY
Bacterial endocarditis was diagnosed in a 4-year-old male German Shorthaired Pointer with a 4-month history of shifting lameness and intermittent fever. The dog died in spite of treatment for progressive depression and dehydration. Blood cultures were positive for Erysipelothrix rhusiopathiae strain 7, which is known to be pathogenic for dogs. The clinical diagnosis was confirmed at necropsy.
Choroid Plexus Tumors in the Dog
Authors: Zaki Farouk A. , Nafe Lawrence A. 
Published: February 2025

SUMMARY
Clinical and necropsy records for nine dogs with tumors of the choroid plexus were reviewed. In seven of the dogs, the tumors were on the left side of the fourth ventricle. All of the dogs were males, ranging in age from 13 months to 9 years. Upper motor neuron tetraparesis and positional nystagmus were the most common neurologic signs. Less frequently recorded were head tilt, vomiting, bradycardia, and signs of cranial nerve dysfunction. Alteration in consciousness was evident in four of the dogs and ranged from personality changes to coma.
A Bleeding Disease (von Willebrand's Disease) in a Chesapeake Bay Retriever
Authors: Johnson Gary S. , Lees George E. , Benson Roger E. , Rosborough Terry K. , Dodds W. Jean 
Published: February 2025

SUMMARY
A bleeding disease similar to von Willebrand's disease in man was diagnosed in a 6-month-old Chesapeake Bay Retriever with recurrent, protracted gingival hemorrhage that responded rapidly to fresh, whole blood transfusions. The dog had a prolonged bleeding time and low plasma factor VIII coagulant activity (18%). The plasma had no detectable factor VIII-related antigen or von Willebrand factor, as measured by ristocetin-cofactor and polybrene-cofactor activities. The dam of the dog had a plasma factor VIII-related antigen concentration (32%) well below the normal range. The antigen in the sire's plasma was at the low end of the normal range, as was the polybrene-cofactor of both the sire and the dam. These data suggested an inherited basis for von Willebrand's disease in this dog.
Prevalence of Bovine Leukemia Virus Antibody in Seven Herds of Holstein-Friesian Cattle
Authors: Evermann James F. , DiGiacomo Ronald F. , Huber Nancy L. 
Published: February 2025

Summary
Sera from 959 Holstein-Friesian cattle in 7 herds were tested for antibody to bovine leukemia virus, using the agar gel immunodiffusion test with glycoprotein antigen. Seropositive cattle were found in 6 herds; 120 (12.5%) were reactors.
In 1 of the herds, the prevalence of seropositive cattle was significantly greater in purebred than in grade cows. Purebred cows raised on the premises had an overall antibody prevalence similar to purchased purebred cows. Purebred cattle more than 2 years old had a significantly greater prevalence of reactors than younger cattle. There was no difference in prevalence by sex.
Disseminated Visceral Coccidiosis in Whooping Cranes
Authors: Carpenter James W. , Spraker Terry R. , Novilla Meliton N. 
Published: February 2025

SUMMARY
Three 13- to 18-day-old whooping cranes (Grus americana) and a 9-year-old whooping crane died in outdoor pens at the Patuxent Wildlife Research Center. The deaths were associated with an overwhelming systemic infection by an intracellular protozoan parasite, which resulted in enteritis, granulomatous bronchopneumonia, hepatitis, splenitis, and myocarditis. The clinical, histopathologic, and electron microscopic findings were similar to those in sandhill cranes (Grus canadensis) at the Patuxent Center found to be infected with Eimeria reichenowi and E gruis. Since these eimerian species also parasitize wild whooping cranes, this parasite might be an important pathogenic agent for this species.
Chronic Chondritis of the Equine Arytenoid Cartilage
Authors: Haynes P. F. , Snider T. G. , McClure J. R. , McClure J. J. 
Published: February 2025

SUMMARY
Chronic chondritis of the arytenoid cartilage was diagnosed in 7 male Thoroughbred horses examined for obstructive upper airway disorders. The history of the cases was characterized by a 3- to 6-month progression of exercise intolerance and inspiratory dyspnea during exercise. Endoscopy revealed marked asymmetry of the rima glottidis, partial or complete inability to abduct the involved cartilage, and axial displacement of the involved arytenoid cartilage. In less severe cases, the disorder was confused with laryngeal hemiplegia. Focal elevated lesions of the involved cartilage, which were frequently seen, produced contact lesions on the contralateral cartilage. Subtotal arytenoidectomy was performed in 6 cases. Histologic examination of the removed cartilages revealed marked lamination of the cartilage with fibrous connective tissue. Granulating sinus tracts were seen in 3 cases. The surgical intervention resulted in marked improvement of exercise intolerance in 5 cases.
A Complication of Cryptorchid Castration in Three Horses
Authors: Trotter Gayle W. , Aanes W. A. 
Published: February 2025

SUMMARY
During an 8-month period, 3 horses were examined because of incomplete cryptorchid castration. Each horse had had surgery to remove 1 retained testis. In each case, the attending veterinarian believed castration had been adequately completed.
History, rectal examination findings, and in 2 cases, high serum testosterone concentration were factors that led to the decision to do exploratory surgery on each horse. In each case, initial surgery had resulted in surgical removal of the tail of the epididymis, which was mistaken for testicular tissue.
Tracheal Reconstruction by Resection and End-to-End Anastomosis in the Horse
Authors: Tate L. P. , Koch D. B. , Sembrat R. F. , Boles C. L. 
Published: February 2025

SUMMARY
A surgical technique for resection of a portion of the trachea followed by end-to-end anastomosis was developed on 4 clinically normal horses. The trachea healed without complications in 3 of the horses in which 3 tracheal cartilages were removed. Five tracheal cartilages were removed from the 4th horse. It had to be euthanatized because of excessive suture line tension and wound disruption, which occurred during recovery from anesthesia. Suture line tension was measured on 3 other clinically normal horses positioned in dorsal recumbency immediately after euthanasia after 3 and 5 tracheal cartilages had been removed and before and after flexion of the neck to 90 degrees. Suture line tension was reduced by approximately 50% when the neck was flexed. Similarly, the force required to appose the cut ends of the trachea was nearly doubled when 5 rather than 3 tracheal cartilages were removed.
The surgical technique was performed on 1 horse and 1 pony with partial obstruction of the trachea. In the pony, 5 tracheal cartilages were resected. It was able to return to successful show competition. In the horse, 4 tracheal cartilages were removed. This horse died of complications resulting from bilateral hindlimb myositis, but the tracheal anastomosis was intact, sealed, and healing well.
Intestinal Infarction Associated with Mesenteric Vascular Thrombotic Disease in the Horse
Authors: White N. A. 
Published: February 2025

SUMMARY
Intestinal infarction associated with cranial mesenteric artery thrombosis, without strangulation obstruction of the intestine, was studied in 18 horses. Findings normally of value in evaluating horses with acute abdominal pain (heart rate, rectal palpation findings, gastric reflux) or classification of the degree of pain were not helpful in diagnosing the problem. Similarly, packed cell volume, plasma total protein, circulating white blood cell count, peritoneal white blood cell count, and peritoneal fluid total protein were not of value in predicting severity of the intestinal damage, location of infarction, or patient survival. In one half of the cases, peritoneal fluid color was of aid in distinguishing intestinal infarction from strangulation. Findings on gross dissection and limited histologic examination did not support the premise that thromboembolism was the major mechanism for production of infarction. In most of the horses, a thrombus or embolus was not found in the peripheral mesenteric vessels.
Metabolic Abnormalities Associated with Rupture of the Urinary Bladder in Neonatal Foals
Authors: Behr M. J. , Hackett R. P. , Bentinck-Smith J. , Hillman R. B. , King J. M. , Tennant B. C. 
Published: February 2025

SUMMARY
Rupture of the urinary bladder was diagnosed in 4 neonatal male foals. Marked hyponatremia, hypochloremia, and hyperkalemia developed in all 4 cases, and the electrolyte abnormalities were considered to be of potential diagnostic value. Blood urea nitrogen concentration was normal or only slightly higher than normal in 3 of 4 cases and therefore was not a reliable diagnostic test.
Aflatoxicosis in Horses
Authors: Angsubhakorn S. , Poomvises P. , Romruen K. , Newberne P. M. 
Published: February 2025

SUMMARY
Two episodes of acute aflatoxin poisoning in horses suggest that horses are susceptible to the toxic effects of this mycotoxin. Lesions associated with exposure to aflatoxin included encephalomalacia of cerebral hemispheres, fatty degeneration, necrosis, bile duct hyperplasia, fibrosis of the liver, fatty infiltration of the kidney, hemorrhagic enteritis, and myocardial degeneration. Hypoglycemia, hyperlipidemia, and depletion of lymphocytes accompanied these lesions. The diagnosis was based on gross and histopathologic observations, consistent with observations of other species poisoned with aflatoxin, and isolation of the toxin from feed and animal tissues. Removing contaminated feed prevented further morbidity or mortality.
Bone Marrow Hypoplasia in a Feminized Dog with a Sertoli Cell Tumor
Authors: Edwards David F. 
Published: February 2025

SUMMARY
A male Cairn Terrier was examined because of feminization and alopecia. The findings of unilateral cryptorchidism and a palpable abdominal mass suggested a neoplastic retained testis. Surgical excision of a Sertoli cell tumor led to remission of clinical signs; however, pre- and postoperative blood analyses identified progressive leukopenia and thrombocytopenia.