bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ketamine and the arrhythmogenic dose of epinephrine in cats anesthetized with halothane and isoflurane
Authors: Bednarski Richard M. , Majors Lynda J. 
Published: February 2025

SUMMARY
Epinephrine-induced arrhythmias were studied in 4 cats (group A), using a 4 × 4 Latin square design. Each cat was anesthetized 4 times, 1 week apart, with halothane (1.5% end expired), isoflurane (2.0% end expired), and halothane or isoflurane preceded by ketamine administered im (8.8 mg/kg). Lead II of the ecg and femoral artery pressure were recorded. Epinephrine was infused in progressively doubled rates (initial rate = 0.125 μg/kg/min) for a maximum of 2.5 minutes or until at least 4 ventricular premature depolarizations occurred within 15 s of each other. The arrhythmogenic dose of epinephrine (ade; μg/kg) was calculated as the product of infusion rate and time to arrhythmia. The ade (X ± sd) during anesthesia with halothane alone and with ketamine-halothane anesthesia were 1.33 ± 0.65 and 1.37 ± 0.59 μg/kg, respectively; during anesthesia with isoflurane alone and ketamine-isoflurane anesthesia, the ade were 9.34 ± 1.29 and 16.16 ± 3.63 μg/kg, respectively. The ade was significantly greater (P < 0.05) during isoflurane anesthesia and ketamine-isoflurane anesthesia than during halothane anesthesia. The percentages of change in systolic blood pressure (X ± sd) at the ade during halothane, ketamine-halothane, isoflurane, and ketamine-isoflurane were 31 ± 34, 41 ± 17, 127 ± 27, and 148 ± 57, respectively. The percentages of change in blood pressure during isoflurane anesthesia and ketamine-isoflurane anesthesia were significantly (P < 0.05) greater than during halothane anesthesia. The percentages of change in heart rate (X ± sd) at the ade during halothane, ketamine-halothane, isoflurane, and ketamine-isoflurane were 20 ± 15, 16 ± 14, 14 ± 18, and 0 ± 27, respectively.
Five additional cats (group B) were anesthetized on 2 occasions, 1 week apart, with halothane (1.5% end expired) and ketamine infusion (76 μg/kg/min) or isoflurane (2.0% end expired) and ketamine infusion (76 μg/kg/min). The ade was determined after the cats had been anesthetized for 4 hours. The ade (X ± sd) during ketamine infusion-halothane anesthesia and ketamine infusionisoflurane anesthesia were 0.57 ± 0.35 μg/kg and 6.63 ± 4.28 μg/kg, respectively. The percentages of change in systolic blood pressure at the ade during ketamine infusion-halothane anesthesia and ketamine infusion-isoflurane anesthesia were 35 ± 29 and 156 ± 19, respectively. The percentages of change in heart rate at the ade during ketamine infusion-halothane anesthesia and ketamine infusion-isoflurane anesthesia were 22 ± 11 and 77 ± 78, respectively.
Halothane-catecholamine arrhythmias in swine (Sus scrofa)
Authors: Tranquilli W. J. , Thurmon J. C. , Benson G. J. 
Published: February 2025

SUMMARY
The arrhythmogenic dose of epinephrine (ade) was determined in 6 pigs during steady-state anesthesia (1.5% halothane in O2) and steady-state anesthesia plus xylazine (1.1 mg·kg−1·hr−1; iv infusion) and after either prazosin (αl) or metoprolol (β1) adrenergic blockade during halothane-xylazine (h-x) anesthesia. A constant infusion (1, 2, 3, 5, and 10 μg·kg−1·min−1) of freshly mixed epinephrine (100 μg·ml−1 in saline solution) was used to determine ade. The ade was defined as the total dose of epinephrine which produced 4 or more continuous or intermittent, premature, ventricular contractions within a 15-s period. The mean epinephrine total dose values during 1.5% halothane anesthesia, h-x anesthesia alone, or h-x anesthesia after either prazosin (0.1 mg·kg−1) or metoprolol (0.5 mg·kg−1) adrenergic blockade were 3.60 ± 0.844, 2.68 ± 0.402, 11.85 ± 3.804, and 5.17 ± 0.587 μg·kg−1, respectively. Xylazine administration did not significantly decrease ade, although mean arterial pressure significantly increased. Prazosin administration significantly increased ade and was associated with an increased heart rate and a decreased mean arterial pressure. We conclude that α1-blockade with prazosin is more protective to epinephrine-induced arrhythmias in h-x-anesthetized pigs than is β1-blockade with metoprolol.
Cardiopulmonary responses of swine to intravenous infusion of guaifenesin, ketamine, and xylazine
Authors: Thurmon J. C. , Tranquilli W. J. , Benson G. J. 
Published: February 2025

SUMMARY
Swine were anesthetized with a 5% solution of dextrose in water containing 50 mg of guaifenesin, 1 mg of ketamine, and 1 mg of xylazine · ml−1 (g-k-x) infused iv at a rate of 2.2 ml · kg−1 · hr−1. Mean arterial blood pressure and systemic vascular resistance were significantly increased from base-line values throughout the 2 hours of g-k-x infusion. Cardiac index decreased significantly initially, but returned to near base line at 30 minutes. Fifteen minutes after g-k-x infusion was discontinued, cardiac index was not significantly different from base line. Heart rate decreased significantly from base line 90 minutes after infusion of g-k-x began and remained so throughout the study. However, the mean heart rate remained within the acceptable range for swine. Rate-pressure product was not significantly altered. The PaCO2 decreased, and arterial pH increased significantly from base line, supporting our clinical impression that pigs breathe well when anesthetized with g-k-x. We conclude that g-k-x is a satisfactory combination of drugs for induction and maintenance of surgical anesthesia in healthy swine for a period of 2 hours.
Influence of thyroid function on the pharmacokinetics of gentamicin in pigs
Authors: Riond Jean-Luc , Dix Lynn P. , Riviere J. Edmond 
Published: February 2025

SUMMARY
Hypothyroidism or hyperthyroidism was induced in 10 pigs (5 pigs/group) and each pig was administered gentamicin (6 mg/kg of body weight, iv). Low thyroxine and triiodothyronine resulted in a decrease in creatinine clearance (P = 0.04), an increase in serum creatinine concentration (P = 0.003), and a decrease in gentamicin systemic clearance (P = 0.002), compared with findings in control pigs (n = 5). These effects probably were secondary to a decreased glomerular filtration rate associated with hypothyroidism. A strong correlation among the 3 treatment groups was found between gentamicin systemic clearance and creatinine clearance (r = 0.72; P = 0.004) and between gentamicin systemic clearance and serum creatinine concentration (r = −0.77; P = 0.0007). Hyperthyroidism induced a slight but significant decrease in protein binding (P = 0 002). However, the significant changes in the hypothyroid pigs and the hyperthyroid pigs were not of a magnitude sufficient to alter gentamicin elimination half-life. Gentamicin disposition was best described, with a 4-compartment open model.
Identification of Brucella abortus in formalin-fixed, paraffin-embedded tissues of cows, goats, and mice with an avidin-biotin-peroxidase complex immunoenzymatic staining technique
Authors: Meador Vincent P. , Tabatabai Louisa B. , Hagemoser Wayne A. , Deyoe Billy L. 
Published: February 2025

SUMMARY
An avidin-biotin-peroxidase complex immunoenzymatic staining technique was evaluated for light microscopic detection of Brucella organisms in formalin-fixed, paraffin-embedded tissues. Tissues from cows, goats, and mice inoculated with B abortus strain 2308 were examined, using rabbit antiserum to Brucella cell surface protein as primary antibody. Stained organisms were identified histologically in tissue sections containing B abortus, as detected by bacteriologic examination of duplicate nonprocessed tissue samples. Bacillus sp, Corynebacterium pyogenes, Escherichia coli, Listeria monocytogenes, Pasteurella haemolytica, P multocida. Salmonella typhimurium, Staphylococcus sp, and Streptococcus sp did not stain with this system, using anti-Brucella cell surface protein primary antibody, thus indicating specificity for Brucella organisms.
Physiologic aging of mature porcine erythrocytes: Effects of various metabolites, antimetabolites, and physical stressors
Authors: Kiel Johnathan L. , Erwin David N. 
Published: February 2025

SUMMARY
Red blood cells were collected from Landrace × Duroc pigs in pooled and single batches. The rbc were stored for 24 hours to 20 days and exposed to 1 or more chemical and physical stressors. The chemicals were pyruvate, lactate, inosine, concanavalin A-luminol-bovine serum albumin conjugate, hydrogen peroxide, l-mimosine, and 3-amino-l-tyrosine. Physical stressors included thermogenic microwave radiation (2,450 MHz, mean specific absorption rate of 91 W/kg) and conventional heating with hot air or hot-water bath. Heating erythrocytes to 43 C for 10 minutes with microwaves or hot air did not significantly (P > 0.05) increase hemolysis, compared with hemolysis of rbc at 4 C (controls). Pyruvate or lactate did not affect the rbc under these conditions. Hemolysis of cells coated with concanavalin A-luminol-bovine serum albumin and heated to 43 C for 10 minutes by use of microwaves or hot air was significantly (P < 0.05 by Student's t test) greater (48%) than that of rbc at 4 C (controls). The method of heating or the presence of pyruvate, lactate, or inosine did not have a significant (P > 0.05) effect on hemolysis. Lysis of rbc (14 days after collection) coated with concanavalin A-luminol-bovine serum albumin and stored at 4 C was not significantly different (P > 0.05) than that of noncoated cells (6 days after collection) stored at 4 C (control). When rbc were heated 20 days after collection to 48 C for 30 minutes, using a hot water bath, hemolysis was 60.6% greater than that of control cells (4 C). The l-mimosine (340 μM) did not affect thermal hemolysis. The 3-amino-l-tyrosine (74 μM) suppressed thermal hemolysis to that of the controls. When rbc were treated 19 days after collection with 44 mM H2O2 at 37 C for 15 minutes, their binding capacity for luminol-bovine serum albumin was 721% more than that of control cells at 37 C. In a second single batch of rbc, the increase in binding induced by H2O2 (11.7 mM) was inhibited 51% by 1.49 mM 3-amino-l-tyrosine. Red blood cells collected 72 hours before use and preincubated with pyruvate (1.33 mM) for 30 minutes at 37 C (hot air) had 2.66 times greater luminol-bovine serum albumin binding than did controls (37 C). Preincubation with 1.49 mM 3-amino-l-tyrosine totally inhibited the increase in binding with pyruvate. Therefore, the effectiveness of 3-amino-l-tyrosine for protecting natural membrane components from oxidation is related to its thermoprotective properties. The luminol-bovine serum albumin binding assay was a sensitive, simple technique for detecting oxidative physiologic aging of porcine rbc.
Pathogenicity and immunogenicity of piliated and nonpiliated phases of Moraxella bovis in calves
Authors: Jayappa Huchappa G. , Lehr Craig 
Published: February 2025

SUMMARY
Pathogenicity evaluations of Moraxella bovis strain EPP 63 grown in the piliated and nonpiliated phase indicated that the organism grown in the piliated phase induced clinical keratoconjunctivitis, whereas the organism grown in the nonpiliated phase did not induce disease under identical challenge conditions. Calves inoculated with culture grown in the piliated phase developed significantly (P < 0.01) higher lesion scores than did calves inoculated with culture grown in the nonpiliated phase. Vaccination/challenge exposure evaluations indicated that calves immunized with vaccine prepared from piliated culture had significantly lower lesion scores than did control calves (P < 0.001) or calves immunized with vaccine prepared from nonpiliated culture (P < 0.05). Similarly, calves immunized with piliated vaccine developed a significantly higher antibody titer against purified pili. Nonvaccinated controls and calves immunized with nonpiliated vaccine did not develop a significant increase in antibody titer. The results indicate that M bovis pili constitute an important factor in the pathogenicity of keratoconjunctivitis and may be used as a vaccine in the control of keratoconjunctivitis in cattle.
Genetic relatedness of disease-associated field isolates of bovid herpesvirus type 4
Authors: Henry Berch E. , Ota Ron , Evermann James F. 
Published: February 2025

SUMMARY
Eight field isolates of bovid herpesvirus type 4 (bhv-4) were examined by restriction analysis and Southern blot hybridization with respect to their relatedness to one another and to the bhv-4 prototype strain DN-599. Isolates were obtained from cattle exhibiting a range of disease states including abortion, pneumonia, enteritis, metritis, and vaginal blisters. Initial growth studies of all 9 viruses were performed and revealed that the overall rate of virus growth was slow when compared with that of other herpesviruses. Infection with each virus also resulted in the formation of large fused cells, which in addition to the slow growth rate, indicated that the isolates were of the cytomegalovirus type.
Further studies to characterize and compare the various bhv-4 isolates were undertaken by obtaining cell-free virus from infected cell populations. Viral isolates were purified and used as a source of bhv-4 DNA. Purified DNA, representing each of the 8 field isolates and the prototype strain DN-599, were each cleaved with 3 restriction enzymes and were separated by agarose-gel electrophoresis, and the resultant fragment patterns were compared. In general, genomic fragments of the field isolates corresponded to those generated by cleavage of DN-599 DNA, with the exception of the abortion-associated isolate 83-3572. Additional minor differences were also seen between DN-599 DNA and DNA from the other field isolates, but the overall restriction patterns were similar. To confirm that all isolates were members of the bhv-4 type, hybridization studies were performed using DN-599. Each DNA of the isolates was cleaved, separated, blotted to nitrocellulose, and hybridized to radiolabeled DN-599 DNA probe. Seemingly, all isolates were closely related to DN-599, although differences in restriction enzyme cleavage patterns were observed. Because an obvious difference was seen in relation to the abortion-associated isolate 83-3572 and DN-599, additional hybridization studies were done using other restriction enzymes. The 2nd abortion-associated isolate 79-1436 was also included. Isolate 83-3572 was markedly different in genomic organization when compared with those of DN-599 and 79-1436.
Quantitative studies of erythropoiesis in the clinically normal, phlebotomized, and feline leukemia virus-infected cat
Authors: Wardrop K. Jane , Kramer John W. , Abkowitz Janis L. , Clemons Gisela , Adamson John W. 
Published: February 2025

SUMMARY
Erythropoiesis was evaluated in 5 cats at base line with normal pcv and then in the same cats with anemia induced by phlebotomy and in 5 other cats with nonregenerative anemia from community-acquired feline leukemia virus (FeLV) infection. The hematologic evaluation included complete blood cell and reticulocyte counts, marrow morphologic features, determination of serum erythropoietin concentrations by radioimmunoassay, ferrokinetic studies, and in vitro marrow culture of early erythroid progenitors (erythroid burst-forming units; bfu-e) and late erythroid progenitors (erythroid colony-forming units; cfu-e).
Phlebotomized cats developed marrow erythroid hyperplasia and an increased reticulocyte count. Ferrokinetic studies revealed an increase in plasma iron turnover from 1.4 to 3.8 mg of Fe/dl of blood/day and rbc use from 50.4% to 78.5%. The mean cfu-e number and cfu-e/bfu-e ratio increased after phlebotomy, but the increase was not significant (P > 0.05). Serum erythropoietin values did increase significantly.
In FeLV-infected cats, a nonregenerative anemia was demonstrated by marrow erythroid hypoplasia and a low total reticulocyte count. An increased percentage of rubriblasts and prorubricytes was observed in 4 of the 5 cats. Although serum erythropoietin values were high (321 ± 123 mU/ml vs normal 14 ± 1 mU/ml), ferrokinetic data revealed decreased erythropoiesis. Marrow culture studies in the FeLV-infected cats also revealed low numbers of bfu-e and cfu-e, but normal numbers of granulocytemacrophage progenitors remained. Seemingly, the FeLV infection impaired the ability of feline marrow to respond physiologically to anemia.
Clinical biochemical values of llamas: Reference values
Authors: Lassen E. Duane , Pearson Erwin G. , Long Patrick , Schmotzer Wayne B. , Kaneps Andris J. , Riebold Thomas W. 
Published: February 2025

SUMMARY
Fifteen clinical biochemical measurements were done on serum from 64 clinically healthy adult llamas (26 males and 38 females). Values for several of these tests were different from those reported for llamas and from reference values for other domesticated ruminants. Comparison of values between males and females revealed significant differences for several tests. Clinical biochemical values reported in the present study can serve as reference values for adult llamas.
Effect of long-term administration of ketoconazole in cats
Authors: Willard M. D. , Nachreiner R. F. , Howard V. C. , Fooshee S. K. 
Published: February 2025

SUMMARY
Four cats given ketoconazole (30 mg/kg of body weight/day) for 30 days developed dry hair coats and weight loss. Plasma cortisol and serum cholesterol, testosterone, and progesterone did not change significantly (P > 0.01), and significant alterations in serum albumin, calcium, and alkaline phosphatase (P < 0.01) did not preclude use of the drug. Serum testosterone concentrations tended to decrease after 7 days of treatment, but in 2 cats returned to near-pretreatment values by day 30 of treatment, despite continued drug administration. These results were in contrast to those reported in the dog at similar and lesser dosages of ketoconazole.
Endotoxin-induced changes in the hemostatic system in neonatal calves: The effect of antiserum to a mutant Escherichia coli (J-5)
Authors: Morris Debra Deem , Whitlock Robert H. , Merryman Geralyn Schad , Bruce James , Corbeil Lynette B. 
Published: February 2025

SUMMARY
Changes in the hemostatic system were studied in 22 neonatal calves given a small dosage of Escherichia coli endotoxin (0.5 μg/kg) by slow (5-hour) iv infusion. The effect of pretreatment with an antiserum to mutant of E coli O111:B4 (J-5) was evaluated. The platelet count, plasma fibrinogen concentration, prothrombin time, and activated partial thromboplastin time changed significantly from base line during and after endotoxin infusions in all calves. The mean platelet count was significantly decreased from 1 through 24 hours after endotoxin infusion was started. Mean plasma fibrinogen was decreased 2 through 12 hours after endotoxin infusion was started. The mean prothrombin time and activated partial thromboplastin time were significantly greater than base line at 3 to 6 hours and 3 to 12 hours, respectively, after endotoxin infusion was started. Serum concentration of fibrinolytic degradation products remained < 10 μg/ml. Bovine J-5 antiserum did not prevent the endotoxin-induced changes in the hemostatic system of these neonatal calves.
Pharmacokinetics of rifampin given as a single oral dose in foals
Authors: Castro Luis A. , Brown Murray P. , Gronwall Ronald , Houston A. E. , Miles N. 
Published: February 2025

SUMMARY
Six foals from 6 to 8 weeks of age were given a single oral dose of rifampin at a dosage of 10 mg/kg of body weight. Serum rifampin concentrations were measured serially during a 24-hour period. The mean peak serum rifampin concentration was 6.7 μg/ml at 4 hours after treatment. The concentration decreased slowly, and at 24 hours the mean value was 2.7 μg/ml. The elimination half-life was 17.5 hours, and the elimination rate constant was 0.04/hr.
Body fluid concentrations and pharmacokinetics of chloramphenicol given to mares intravenously or by repeated gavage
Authors: Gronwall Ronald , Brown Murray P. , Merritt A. M. , Stone H. W. 
Published: February 2025

SUMMARY
Serum concentrations and the pharmacokinetics of chloramphenicol were determined in 6 healthy mares after a single iv administration (50 mg/kg of body weight) or after the 1st and 5th sequential intragastric (ig) administration (50 mg/kg/6 hours) of chloramphenicol. Synovial fluid, peritoneal fluid, csf, and urinary concentrations of chloramphenicol after the ig administrations also were determined. Mean (± sem) overall elimination rate constant (K) values for the iv, 1st ig, and 5th ig dosages were 0.42 ± 0.064/hr, 0.42 ± 0.049/hr, and 0.29 ± 0.074/hr, respectively, and were not significantly different from one another (P > 0.05). Bioavailability was 40 ± 8.6% after the 1st ig administration and was 21 ± 5.2% after the 5th ig administration. Values for the area under the curve (auc) for the 1st and 5th ig dosages were significantly different from the auc value for the iv dosage, and the auc value for the 5th ig dosage was significantly different from that for the 1st ig dosage. Chloramphenicol was administered to 2 mares in 6 consecutive doses; the first and last doses were given iv and the others were given ig. Mean K values after the 2 iv doses were 0.38 ± 0.112/hr and 0.56 ± 0.078/hr, which were not significantly different from each other or from the mean value for the iv dosage given to all 6 mares. Absorption of chloramphenicol decreased with repeated ig administrations, resulting in lower concentrations of chloramphenicol with subsequent administrations. Five consecutive ig doses of chloramphenicol were administered to 4 of the mares in a separate experiment and did not alter intestinal xylose absorption.
An in vivo model for the study of Bordetella avium adherence to tracheal mucosa in turkeys
Authors: Arp Lawrence H. , Brooks Emily E. 
Published: February 2025

SUMMARY
An in vivo model was developed for studies characterizing the adherence of Bordetella avium to the tracheal mucosa of turkeys. Three-week-old turkeys were anesthetized, and the cervical part of the trachea was isolated after tracheostomy was done. A hemostat was applied craniad to the tracheostomy site to occlude the tracheal lumen. Isolated tracheal segments were filled with an aqueous bacterial inoculum for 1 minute, and then excess inoculum and the hemostat were removed. After 1 hour, a 1-cm section was excised from each tracheal segment, and adherent viable bacteria were quantified. Modifications of the procedure were evaluated to produce a model that was technically simple to do, economical, and reproducible. To examine the validity of the model, adherence of B avium was compared with that of Escherichia coli and Staphylococcus aureus. Adherence of B avium to tracheal mucosa was 17 times greater than that with E coli and 1,550 times greater than that with S aureus. Colonization of the tracheal mucosa by B avium was demonstrated in tracheal sections obtained 6 hours after filling with bacterial inoculum. Because the ciliary clearance mechanism of the tracheal segments remained functional, washing of the tracheal lumen had no effect on numbers of associated bacteria. An important advantage of this model over in vitro models is the excellent preservation of the tracheal mucosal surface.
Antibody-mediated suppression of erythropoiesis in dogs with red blood cell aplasia
Authors: Weiss Douglas J. 
Published: February 2025

SUMMARY
Eight dogs with acquired rbc aplasia were studied. Unfractionated sera and serum immunoglobulin G fractions were examined for the presence of erythroid progenitor cell inhibitors. A serum immunoglobulin G inhibitor directed against precursors of erythroid colony-forming units was detected in 3 of 5 dogs that were direct Coombs' test-negative and in 1 of 3 dogs that were direct Coombs' test-positive. Sera from these dogs were treated with binary ethyleneimine to inactivate any viruses present. The inhibitory effects of the treated serum on erythroid colony-forming units was not ameliorated.