bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Antimicrobial Susceptibility of Pseudomonas aeruginosa by Disk Diffusion and Microdilution Methods
Authors: Cox Hollis Utah , Luther D. Gene 
Published: February 2025

SUMMARY
Disk diffusion susceptibility tests were performed on 180 recent clinical isolates of Pseudomonas aeruginosa. Minimal inhibitory concentration values were determined at the same time by a broth microdilution method. All isolates were sensitive to colistin (< 4 μg/ml), but resistant to ampicillin (≥ 16 μg/ml), cephalothin (≥ 64 μg/ml), and nitrofurantoin (> 64 μg/ml). More than 90% of the isolates were sensitive to gentamicin (median, ≤ 0.25 μg/ml), tobramycin (median, ≤ 0.25 μg/ml), and amikacin (median, ≤ 1.0 μg/ml) and more than 70% were sensitive to carbenicillin (median, 64 μg/ml). When the resistant and intermediate categories were combined, over 90% of the isolates were resistant to tetracycline (median 16 μg/ml), chloramphenicol (median, > 32 μg/ml), kanamycin (median, 16 μg/ml), and trimethoprim-sulfonamide combination (median, 4 μg/ml; 76 μg/ml). Differences between the disk diffusion and microdilution methods in distinguishing resistant isolates of Ρ aeruginosa from sensitive isolates were minor. Complete agreement between the two methods was obtained in 87.0% of the observations.
Urine Concentrations of Chloramphenicol, Tetracycline, and Sulfisoxazole After Oral Administration to Healthy Adult Dogs
Authors: Ling Gerald V. , Conzelman Gaylord M. , Franti Charles E. , Ruby Annette L. 
Published: February 2025

SUMMARY
Chloramphenicol, tetracycline, and sulfisoxazole were administered (orally) in separate trials to clinically healthy adult dogs of both sexes at 8-hour intervals for five consecutive 8-hour test periods. All urine was collected from each dog during each test period and an aliquot from each period was assayed for antimicrobial activity.
Daily doses of the antimicrobics were as follows: chloramphenicol 99 mg/kg of body weight, tetracycline 55 mg/kg, and sulfisoxazole 66 mg/kg. Mean 8-hour urine concentrations (± 1 sd) for chloramphenicol were 124 ± 40 μg/ml; for tetracycline, 138 ± 65 μg/ml; and for sulfisoxazole, 1,466 ± 832 μg/ml. The mean 8-hour percentages of the doses of drug eliminated in active form in the urine were 6.3 ± 2.6% for chloramphenicol, 11.2 ± 2.0% for tetracycline, and 68.5 ± 2.1% for sulfisoxazole.
Lactic Acid and Glucose Metabolism in Healthy, Lactic Acid-Infused, and Diarrheic Calves
Authors: Case G. L. , Phillips R. W. , Cleek J. L. 
Published: February 2025

SUMMARY
Kinetics of glucose and lactate metabolism were measured in healthy (normal) calves, healthy calves infused with lactate, and in calves which had received an enteropathogenic coronavirus inoculum and had become diarrheic. Lactate utilization was positively correlated with blood lactate concentration in the healthy calves, but its turnover was markedly reduced in diarrheic animals. The decreased turnover was not due to inhibition of lactate oxidation, but appeared to relate to decreased gluconeogenesis. Glucose entry rate was not affected by diarrhea, but was a function of glucose concentration.
Caprine Toxoplasmosis: Abortion, Clinical Signs, and Distribution of Toxoplasma in Tissues of Goats Fed Toxoplasma gondii Oocysts
Authors: Dubey J. P. , Sharma S. P. , Lopes Carlos W. G. , Williams Jeffrey F. , Williams Christine S. F. , Weisbrode Steven E. 
Published: February 2025

SUMMARY
Thirteen goats (9 does and 4 bucks) were each inoculated orally with 10,000 infective Toxoplasma gondii oocysts. Three does and one buck were used as noninoculated controls. In 2 to 4 days after inoculation (dai), inoculated goats became dull, pyrectic (40 to 41 C), and anorectic. Three goats died (10, 10, and 14 dai) and two goats were killed (7 and 32 dai) because they were moribund; also, 3 does aborted, 2 had weak kids, and 2 had dead fetuses. Toxoplasma was isolated from the placenta of three goats, and the fetal tissues of four goats. The control goats remained asymptomatic.
The distribution of T gondii in blood and other tissues was studied by inoculation of mice with caprine tissues. Parasitemia was detected in 7 of 7 goats—beginning 4 dai in 1 goat, 5 dai in 5 goats, and 8 dai in 1 goat. The parasitemia lasted 3 to 10 days. Toxoplasma was isolated from the milk of 2 goats at 12 to 14 dai. Toxoplasma was isolated from 15 or more tissues of 5 goats killed 7 to 35 dai and from 10 tissues of 2 goats killed 69 and 95 dai.
Effects of Neomycin on the Waveform of Auditory-Evoked Brain Stem Potentials in Dogs
Authors: Morgan Joel L. , Coulter Dwight B. , Marshall Arvle E. , Goetsch Dennis D. 
Published: February 2025

SUMMARY AND CONCLUSIONS
Neomycin sulfate was administered intravenously to eight mixed-breed dogs at a dosage of 30 mg/kg/day for as long as 50 days. Auditory-evoked brain stem potentials (aebp) were recorded from the dogs three times a week. The aebp amplitudes and latencies from the eight treated and the eight control dogs were compared.
All treated dogs eventually exhibited an isoelectric aebp. The time required for the aebp waveform loss to occur in the treated dogs varied between 22 and 50 days. The aebp waveforms were still isoelectric when measured as long as 150 days after neomycin administration was stopped. The fact that aebp did not return would tend to support the findings of others that the loss of the receptors in the inner ear, due to neomycin toxicity, is permanent.
The results of this electrophysiologic study indicate that the organ of Corti (organum spirale) is the site of pathologic changes in the auditory system that result from neomycin treatment.
Susceptibility of Nonhuman Primate Species to Infection by Simian Rotavirus SA-11
Authors: Soike K. F. , Gary G. W. , Gibson S. 
Published: February 2025

SUMMARY
Enzyme-linked immunosorbent assay examination of sera from three nonhuman primate species demonstrated the presence of antibody reacting with simian rotavirus SA-11 and calf rotavirus C486. The occurrence of this antibody in sera from adult, wild-caught animals suggests natural rotavirus infection. The occurrence of antibody was highest in the chimpanzee and declined, respectively, in the rhesus macaque and in the squirrel monkey.
Inoculation of three infant rhesus macaques, a nursery-reared chimpanzee, and a cesarian-derived nursery-reared baboon with SA-11 virus resulted in enteric infection, with virus excretion beginning 48 to 72 hours after oral administration of the virus. Clinical disease, as manifested by diarrhea, was observed only in the chimpanzee.
Inoculation of ten squirrel monkeys, from 30 to 191 days old, induced infection only in the monkey inoculated at 30 days of age. This monkey became ill within 48 hours after viral administration and was euthanatized. Necropsy demonstrated a generalized infection, with virus recovered from lung, liver, kidney, spleen, and intestine. The remaining nine inoculated squirrel monkeys failed to develop enteric infection and did not respond with antibody to SA-11 virus.
An Approach to the Anesthetic Requirements for a Chronic Animal Preparation
Authors: Bagshaw Roger J. , Cox Robert H. 
Published: February 2025

SUMMARY
The general anesthetic requirements for the preparation of a chronic experimental animal are discussed with respect to the implantation of an electromagnetic flow probe around the ascending aorta of the dog. After preanesthetic management and induction, several techniques for the maintenance of anesthesia are briefly considered. A technique is emphasized that combines a light general anesthetic with a regional nerve block and best fulfills the general anesthetic requirements.
Urine Concentrations of Five Penicillins Following Oral Administration to Normal Adult Dogs
Authors: Ling Gerald V. , Conzelman Gaylord M. , Franti Charles E. , Ruby Annette L. 
Published: February 2025

SUMMARY
Penicillin G, penicillin V, ampicillin, hetacillin, and amoxicillin were administered separately per os to clinically normal adult dogs of both sexes at 8-hour intervals for five consecutive 8-hour test periods. All urine was collected from each dog during each test period and was assayed for antimicrobial activity.
Daily doses of the antimicrobics used were as follows: penicillin G, 110,000 U/kg of body weight; penicillin V, 77 mg/kg; ampicillin, 77 mg/kg; hetacillin, 77 mg/kg; and amoxicillin, 33 mg/kg. Mean 8-hour urine concentrations (± 1 sd) were as follows: penicillin G, 294 ± 210 U/ml; penicillin V, 148 ± 98 μg/ml; ampicillin, 309 ± 55 μg/ml; hetacillin, 300 ± 156 μg/ml, and amoxicillin 201 ± 93 μg/ml. Among the three antimicrobials administered at the same daily dosage, penicillin V, ampicillin, and hetacillin, the mean urine concentrations of penicillin V were significantly lower (P < 0.01) than were concentrations of ampicillin and hetacillin. The mean urine concentrations of the latter two did not differ significantly (P > 0.05).
Electromagnetic Measurements of Metacarpal Blood Flow in Nonanesthetized Horses
Authors: Scott E. A. , Sandler G. A. 
Published: February 2025

SUMMARY
Blood flow (milliliter/minute) was measured in the medial palmar artery of 12 horses, using electromagnetic flow equipment. Extraluminal flow probes were surgically placed around the artery and base-line blood flows were recorded during surgical manipulation. After horses had recovered from anesthesia, blood flows were recorded each day for 11 days.
According to mean average blood flows, horses were allotted to two groups: group 1—those with predominately normal flow characteristics, and group 2—those horses with predominately abnormal flow features.
Average daily mean blood flows in the medial palmar artery () of group 1 horses were 103 ml/min (min-max, 10 to 210), and for group 2, 49 ml/min (min-max, 0 to 300).
Clostridium difficile-Associated Cecitis in Guinea Pigs Exposed to Penicillin
Authors: Lowe Bruce R. , Fox James G. , Bartlett John G. 
Published: February 2025

SUMMARY
Penicillin treatment resulted in lethal hemorrhagic cecitis in seven of eight guinea pigs. Cecal contents at necropsy from all seven animals contained a cytopathic toxin which was neutralized by Clostridium sordellii and C difficile antitoxins. Bacteriologic cultural examinations of these specimens yielded penicillin-sensitive strains of C difficile which produced a similar or identical cytotoxin in vitro. Stools obtained before penicillin administration and cecal contents from control animals lacked a cytotoxin and cultures failed to yield C difficile. Intracecal injection of cell-free supernatant of C difficile broth cultures reproduced the lesion noted with penicillin treatment. These results implicate C difficile as an agent of penicillin-induced lethal hemorrhagic cecitis in guinea pigs.
Pasteurella multocida: Antibody-Mediated Resistance to Virulent Challenge Exposure in Vaccinated Turkeys
Authors: Nathanson Robert M. , Hofstad M. S. , Jeska Edward L. 
Published: February 2025

SUMMARY
Aspects of antibody-mediated resistance to Pasteurella multocida infection in vaccinated turkeys were investigated. Pasteurella immune serum obtained from vaccinated turkeys was shown to confer temporary protection to nonvaccinated turkey poults. Recipients given immune serum were free of clinical signs of disease for at least 8 days after im challenge exposure with virulent Ρ multocida 1059. All turkeys given normal serum died within 36 hours of challenge exposure.
Vaccinated bursectomized turkeys were more susceptible to im challenge exposure than were vaccinated non-bursectomized turkeys. In two of three trials, mortality also occurred earlier in the bursectomized groups when compared with mortality in the control groups. The presence of specific antibody may be an important determinant in resistance to Pasteurella infection.
Histopathologic Evaluation of Livers of Pregnant Hamsters Infected with Leptospira canicola
Authors: Sapp W. J. , Siddique I. H. , Williams C. S. , Graham T. 
Published: February 2025

SUMMARY
Pregnant hamsters were inoculated with Leptospira canicola by an intraperitoneal route. Grossly, the livers were enlarged and pale yellow. On light microscopic examination, disruption of the hepatic cords, as well as granulation of hepatocyte cytoplasm, was evident.
On electron microscopic examination, the livers had evidence of severe cellular degradation as early as post-inoculation hour (pih) 24. At pih 96, pathologic changes were more pronounced. The rough endoplasmic reticulum was swollen and there was membrane disruption. These changes were not observed in the livers of control animals. In addition, livers of the fetuses at pih 72 exhibited severe degenerative changes.
Effect of Dietary Iodide on Hypophyseal and Thyroid Hormone Secretions in Holstein-Friesian Heifers
Authors: Leung K. , Convey E. Μ. , Conner G. H. 
Published: February 2025

SUMMARY
Our objective was to determine the effects of feeding supplemental iodide on development of the hypophysisthyroid axis in Holstein-Friesian heifers. Forty heifers, 11 to 15 weeks of age, were assigned to be fed 0, 50, 250, or 1,250 mg of iodide daily in the form of ethylenediamine dihydriodide for 162 days.
Daily weight gains of heifers fed 250 or 1,250 mg of supplemental iodide daily were less than for control heifers for 21 and 77 days, respectively, after onset of treatment. Thereafter, supplemental iodide had no effect on weight gain. Thyroidal weights, when adjusted for body weight differences, were greatest in heifers fed 1,250 mg of supplemental iodide daily, whereas hypophyseal and adrenal weights were unaffected by iodide feeding. In addition, total glucocorticoid concentrations in serum were similar among treatment groups.
Basal thyrotropin (thyroid-stimulating hormone; tsh) concentrations in serum of all heifers were not different throughout the treatment period, with the single exception of day 78 when tsh values for heifers fed 1,250 mg of iodide were higher than for controls. On the same day, concentrations of tri-iodothyronine (T3) and thyroxine (T4) in these heifers (1,250 mg) reached nadirs of 0.7 ng/ml and 27.4 ng/ml, respectively. Although concentrations of both thyroid hormones increased thereafter, they remained less than that of controls.
The tsh release after administration of thyrotropin-releasing hormone (trh) was greater in heifers fed 1,250 mg of supplemental iodide daily than that of controls beginning on day 22 of treatment and continuing throughout the entire iodide feeding period. However, the increases in serum T3 and T4 that occurred in response to the trh-induced release of tsh were not altered by treatment. Thus, the amount of tsh released after trh may have induced maximum release of thyroid hormone in all treatment groups.
Basal concentrations of T3 and T4 in heifers which were given 1,250 mg of iodide daily remained less than controls 10 days after the end of treatment. However, tsh responses to trh were no longer statistically different among groups.
Based on these observations, we conclude that supplemental iodide at quantities less than 250 mg daily (160 times the daily National Research Council requirement) does not affect development of the hypophysis-thyroid axis in growing dairy heifers.
Effects of Injectable Famphur on Young Brahman and Angus Cattle
Authors: Randell Wallace F. , Bradley Richard E. 
Published: February 2025

SUMMARY
Clinical responses were monitored in young Angus and Brahman bulls given im injections of an experimental solution of 35% famphur in a dose 5 times greater than the recommended dose (83.2 mg/kg). Five of the 6 treated Brahman bulls had severe clinical signs of organophosphorous toxicosis, and 4 died within 48 hours after they were dosed. Only 1 of the 5 treated Angus bulls showed clinical signs of toxicosis and it recovered.
In a subsequent trial, clinical and cholinesterase responses were monitored in young Brahman bulls, steers, and heifers given famphur at different dosages. Highly significant (P < 0.001) rbc cholinesterase inhibition over the 28-day trial was observed in animals given 16.6, 33.3, and 49.9 mg of the drug/kg. In comparison to Brahman heifers and steers, a lower treatment level of famphur (33.3 mg/kg) induced toxicosis in bulls. However, no significant differences in rbc or plasma cholinesterase inhibition were found to be due to treatment-sex interactions.
In Vitro Effect of Isoprinosine on Rabies Virus
Authors: Hernández-Jáuregui P. , González-Vega D. , Cruz-Lavín E. , Hernández-Baumgarten E. 
Published: February 2025

SUMMARY
The in vitro effect of isoprinosine, an antiviral compound, was evaluated on ERA and V319 rabies viral strains. Isoprinosine diminished the number of immunofluorescent cells, viral titers, and structures involved in rabies virus replication. Mechanism of antiviral action was probably mediated by modification of the polyribosome conformation and function.
Application of the Amplified Enzyme-Linked Immunosorbent Assay: Comparative Quantitation of Bovine Serum IgG1, IgG2, IgA, and IgM Antibodies
Authors: Butler J. E. , McGivern P. L. , Cantarero L. A. , Peterson L. 
Published: February 2025

SUMMARY
The comparative quantitation of serum antibodies to a defined antigen, using the amplified enzyme-linked immunosorbent assay (a-elisa), has been demonstrated in a model system in which bovine immunoglobulins (Ig) IgG1, IgG2, IgA, and IgM antibodies to human serum albumin (hsa) were measured. Comparative measurements are facilitated because the same enzyme-antibody complex is used for measuring all 4 isotypes. Serum dilutions from 1:100 to 1:50,000,000 were titrated and, when graphed logarithmically, yielded dose-response plots that contained a linear segment for all but IgA anti-hsa. Data obtained with whole serum and fractions enriched in IgA- and IgM-anti-hsa indicated that dimeric IgA antibodies may compete poorly with those of the IgM and IgG classes and that IgM antibodies are more avid than those of the IgG1 and IgG2 subclasses. Plateauing of complete a-elisa titrations at optical density (OD)400 nm values lower than those observed for their standard-curve counterparts was interpreted to result from saturation of the antigen.
Quantitation was accomplished through the use of standard curves prepared by adsorbing purified, radio-labeled Ig of the 4 isotypes directly to polystyrene. These plots were also valuable in evaluating antiglobulin specificity and potency and for ascertaining linearity in the absence of the primary antibody to be measured, as well as standard curves for determining antibody content in absolute terms. The absolute amounts of IgG1 and IgG2 antibodies to hsa were similar to those determined by quantitative precipitation and constituted about 25% of the total IgG1 and IgG2 in a hyperimmune bovine serum. Only 5% of the serum IgM was specific antibody to hsa. The specificity of various anti-bovine globulin reagents was further shown by demonstrating the characteristic distribution of IgG1, IgG2, IgM, and IgA anti-hsa in serum fractionated on Sephadex QAE-50 and in sucrose density-gradients.
Finally, data on the influence of enzyme-complex concentrations, complex-step incubation times, and the reaction kinetics of soluble antibody-enzyme complexes on a-elisa results are presented.
Morphogenesis of Vesiculation in Foot-and-Mouth Disease
Authors: Yilma Tilahun 
Published: February 2025

SUMMARY
The morphogenesis of vesiculation in cattle inoculated (aerosol exposure) with foot-and-mouth disease virus was investigated by examining alternate, frozen sections of selected tissues stained by fluorescent antibody technique and with hematoxylin and eosin. Viremia preceded the development of lesions, and virus appeared to be transported to the epithelium via papillae. Lesions were initiated usually by the infection of single cells in the stratum spinosum adjacent to the papillae. Three types of lesions were observed. A vesicle developed mainly from the lysis of swollen, spherical cells and the release of intracellular fluid. The 2nd type of lesion was formed mainly by the accumulation of intercellular edema. The 3rd type was characterized by the absence of a vesicle due to seepage and loss of edema fluid and desiccation of the lesion.
Effect of Intraluminal Oxygen in Intestinal Strangulation Obstruction in Ponies
Authors: Moore J. N. , White N. A. , Trim C. Μ. , Garner H. E. 
Published: February 2025

SUMMARY
This study examined the effect of intraluminal oxygen administration on mucosal morphology following intestinal strangulation obstruction (iso) in anesthetized ponies. The iso was produced by ligation of the intestinal vasculature in 5 ponies for 50 minutes and 2 ponies for 90 minutes. Two ponies served as controls. Light and scanning electron microscopic examination of intestinal biopsy specimens revealed progressive mucosal degeneration following iso in nontreated intestines, whereas high magnification scanning electron microscopic examination documented subtle evidence of microvilli disruption 120 minutes following iso in oxygen-treated intestines.
Influence of Head Height on Arterial Blood Pressure in Standing Horses
Authors: Parry B. W. , Gay C. C. , McCarthy Μ. A. 
Published: February 2025

SUMMARY
Eighteen horses were used to investigate the influence of head position on arterial blood pressure, measured indirectly at the coccygeal artery. Head height significantly altered systolic pressure, diastolic pressure, pulse pressure, and mean arterial pressure, such that head-lowering decreased and head-raising increased all variables.
Thiabendazole-Resistant Strains of Haemonchus and Ostertagia in California Lambs
Authors: Miller James E. , Baker Norman F. 
Published: February 2025

SUMMARY
Ten parasite-free experimental lambs were inoculated intraruminally with a mixed-larvae inoculum which contained approximately 5,000 Haemonchus contortus infective larvae. Five lambs were treated with thiabendazole (66 mg/kg of body weight) and 5 were untreated controls. All lambs were killed 35 days after inoculations were done, and parasites present were recovered. Reduction in numbers of recovered Haemonchus contortus (25.7%) and Ostertagia spp (26.8%) were not significant (P > 0.05).
Caprine Mycoplasmosis: Mycoplasma putrefaciens, a New Cause of Mastitis in Goats
Authors: Adler H. E. , DaMassa A. J. , Brooks D. L. 
Published: February 2025

SUMMARY
Lactating goats given an intramammary inoculation of 50 Mycoplasma putrefaciens in 1/2 of the udder had a high percentage of leukocytes in the milk within 8 days, without involvement of the other half. Larger doses of mycoplasma caused earlier inflammatory changes, but there were no differences in the final disease. In all instances, the viability count of the mycoplasma reached at least 108 organisms/ml before a high percentage of neutrophils were present in milk smears. The California mastitis test was 2+ to 3+ when 1010 Μ putrefaciens/ml were cultured from the secretions. The main features of Μ putrefaciens infection in the udder are the lack of clinical signs and rapid growth of the organisms, followed by inflammatory cells in the milk and complete halt to lactation.
Evidence of Cytocidal Effects of Pasteurella haemolytica on Bovine Peripheral Blood Mononuclear Leukocytes
Authors: Kaehler Karen L. , Markam R. J. F. , Muscoplat Charles C. , Johnson Donald W. 
Published: February 2025

SUMMARY
Pasteurella haemolytica had a pronounced cytocidal effect on bovine mononuclear leukocytes. Mononuclear leukocytes separated from venous blood on Ficoll-diatrizoate and incubated with either P haemolytica or Escherichia coli showed a significantly greater percentage cell death than did cells incubated with Staphylococcus epidermidis or controls. Neither heat-killed nor x-irradiated P haemolytica caused a significant percentage cell death. The cytotoxic potential of P haemolytica was dose related in that cell death among mononuclear leukocytes increased as the ratio of bacteria-to-cells increased. Enriched monocyte cultures showed a higher and less variable rate of cell death than either enriched lymphocyte or mixed leukocyte cultures.