bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of bovine mammary gland macrophage oxidative burst activity in a chemiluminescence assay
Authors: Harmon Barry G. , Adams L. G. 
Published: February 2025

SUMMARY
A major bactericidal mechanism of neutrophils and macrophages is the generation of toxic oxygen-free radicals upon phagocytosis of microbes. Studies were conducted to assess the oxidative metabolism of bovine mammary gland macrophages. Bovine mammary gland macrophages were challenge exposed with a variety of phagocytic stimuli in an in vitro, luminol-assisted chemiluminescence assay. A measurable oxidative burst was observed when macrophages were challenge exposed with heat-aggregated bovine immunoglobulin, opsonified zymosan, and nonopsonified zymosan. Addition of superoxide dismutase decreased mammary gland macrophage chemiluminescence in a dose-dependent manner. Brucella abortus, when opsonified with antiserum, lacteal antibody, or normal serum, produced an oxidative event, whereas nonopsonified B abortus did not. When challenge exposed with phagocytic stimuli, mammary gland macrophages produced an oxidative burst similar to that produced by other phagocytes for which an oxidative event is known to be bactericidal.
Effect of aspirin on ex vivo generation of thromboxane in healthy horses
Authors: Baxter Gary M. , Moore James N. 
Published: February 2025

SUMMARY
Different dosages of aspirin were administered (by nasogastric tube) to 3 groups of 5 healthy adult horses to determine the minimal effective dosage needed to decrease serum thromboxane B2 (TxB2) concentrations and to determine the duration of this decrease. When compared with their base-line serum TxB2 concentrations, horses in group 1 (given 5 mg/kg) had a 71% decrease in TxB2 concentrations at 24 hours after aspirin was given and a 86% decrease at 48 hours; serum TxB2 concentrations were back to base-line values by 120 hours. Horses in group 2 (given 10 mg/kg) had a 60% decrease in TxB2 concentrations at 24 hours after aspirin was given, an 84% decrease at 48 hours, a 48% decrease at 96 hours, and an 18% decrease at 6 days. Horses in group 3 (given 20 mg/kg) had a 68% decrease in TxB2 concentrations at 24 hours, a 93% decrease at 72 hours, an 87% decrease at 96 hours, and a 70% decrease at 6 days after aspirin treatment was given. All groups had a statistically significant decrease in TxB2 concentrations (P < 0.05) by 12 hours after aspirin was given, which persisted 96 hours for group 1 and throughout the study for groups 2 and 3.
The maximal TxB2 decrease was similar among the 3 groups (90% decrease from base line), and there were no significant differences among the TxB2 concentrations between 24 and 72 hours after treatment was given. However, beginning 96 hours after aspirin was given, there was a statistically significant (P < 0.005) dose-dependent increase in duration of aspirin activity. As the aspirin dosage was increased, the rate of return of TxB2 concentrations toward base line significantly decreased.
Contribution of whole blood L-lactate, pyruvate, D-lactate, acetoacetate, and 3-hydroxybutyrate concentrations to the plasma anion gap in horses with intestinal disorders
Authors: Gossett K. A. , Cleghorn B. , Adams R. , Church G. E. , McCoy D. J. , Carakostas M. C. , Flory W. 
Published: February 2025

SUMMARY
Increased anion gap (ag) was due, in part, to l-lactic acidosis in 14 of 14 horses with intestinal disorders. In a few horses, increased whole blood concentrations of d-lactate made a minor contribution to the ag. However, the increase in ag was often greater than the sum of the increases in these 2 acid anions. This unexplained increase was not a result of increases in whole blood pyruvate, 3-hydroxybutyrate, or acetoacetate concentrations or serum albumin or phosphate concentrations. Identification of other anions causing increased ag could lead to better understanding, diagnosis, and treatment of metabolic imbalances in critically ill horses.
Uptake of channel catfish virus from water by channel catfish and bluegills
Authors: Nusbaum Kenneth E. , Grizzle John M. 
Published: February 2025

SUMMARY
Radiolabeled channel catfish virus entered the gills of juvenile channel catfish (Ictalurus punctatus) and was then concentrated in the gut and the liver over 48 hours. Diminution of radioactivity was not detected in these tissues over the course of the experiment. Bluegills (Lepomis macrochirus) were capable of clearing the virus during a period of 48 hours. [3H]Thymidine alone had a different distribution in the channel catfish than did labeled virus.
Pharmacokinetics and renal clearance of sulfamethazine, sulfamerazine, and sulfadiazine and their N4-acetyl and hydroxy metabolites in horses
Authors: Nouws J. F. M. , Firth E. C. , Vree T. B. , Baakman M. 
Published: February 2025

SUMMARY
Plasma disposition, protein binding, urinary recovery, and renal clearance of sulfamethazine (smz), sulfamerazine (smr), and sulfadiazine (sdz) and their N4-acetyl and hydroxy derivatives were studied in 4 horses in a crossover trial. The plasma concentration-time curves of the metabolites paralleled those of the parent drug in the elimination phase. Sulfamethazine and smr were extensively metabolized. In plasma and urine, the main metabolite of the 3 sulfonamides tested was the 5-hydroxypyrimidine derivative, which was highly glucuronidated. Difference in elimination half-life of smz, smr, and sdz could be related to difference in metabolism and renal clearance values. Metabolism speeds drug elimination, producing compounds with higher renal clearance values than those of the parent drug. Methyl substitution in the pyrimidine side chain increased hydroxylation of the parent drug, but prolonged the persistence of the sulfonamides studied in the body. The high concentration of N4-acetyl and hydroxy metabolites of smz and smr in plasma and urine decreased the potential antibacterial activity of the parent drugs. Sulfadiazine was less metabolized, and microbiologically determined sdz concentrations in plasma and urine were slightly lower than those measured by high-performance liquid chromatography.
Healing of experimentally induced corneal ulcers in horses
Authors: Neaderland M. H. , Riis R. C. , Rebhun W. C. , Erb H. N. 
Published: February 2025

SUMMARY
Corneal ulcers to the depth of the anterior third of the stroma were created surgically in both eyes of 10 ponies. One eye in each pony was treated topically with chloramphenicol and 1% atropine ophthalmic ointments 3 times per day; the contralateral eye was not treated topically. All ponies were given phenylbutazone orally for relief of ocular pain.
Fluorescein-stained ulcers were measured once a day. The median healing time of the treated eyes (11 days) and the median healing time of the nontreated eyes (13.5 days) were found not to be significantly different. Clinically, however, more severe complications arose in the nontreated eyes.
Experimental crush of the equine recurrent laryngeal nerve: A study of normal and aberrant reinnervation
Authors: Duncan I. D. , Baker G. J. 
Published: February 2025

SUMMARY
Experimental reinnervation of the equine larynx in healthy ponies was studied after the recurrent laryngeal nerve was crushed, using endoscopic, electromyographic, and microscopic techniques. In 12 ponies, the recurrent laryngeal nerve was crushed unilaterally in the midcervical area. All showed postoperative paralysis of the larynx on the operated side. In 8 ponies, recovery of movement of the vocal folds occurred at different times (2.5 to 8 months) after surgical operation was done. These movements, which were often abnormal, included trembling and asynchronism. In 2 of these ponies, complete return of normal vocal fold function occurred. Return of function was due to reinnervation, as determined by electromyographic examination of the laryngeal muscles and microscopic evaluation of these muscles and the recurrent laryngeal nerves. In the muscles, there was evidence of fiber-type grouping, and the nerves showed regenerative activity. In 3 ponies, there was evidence of aberrant reinnervation, with adductor or abductor muscles discharging during an inappropriate phase of the respiratory cycle. Further evidence that reinnervation occurred in the larynges of these ponies was determined in microscopic sections of the recurrent laryngeal nerves and muscles, which showed regenerative activity and muscle fiber-type grouping, respectively. The endoscopic abnormalities in these ponies were compared with those seen in horses with spontaneous subclinical laryngeal paralysis. However, the possibility that the abnormal endoscopic findings in this latter group of horses are due to aberrant reinnervation is thought to be unlikely.
Passage of exogenous L-thyroxine and triiodothyronine into bovine ejaculate
Authors: Eiler Hugo , Armstrong-Backus Cindy S. 
Published: February 2025

SUMMARY
The metabolic effects of thyroxine (T4) and triiodothyronine (T3) on spermatozoa metabolism and male anatomy have been demonstrated. The metabolic effects of T3 and T4 could affect the physiologic characteristics of the spermatozoa. There are little data on the passage of T4 and T3 into the ejaculate from blood. The passage of exogenous T4 and T3 from the blood into semen was measured after T4 (45 mg) or T3 (37.5 mg) was injected iv into 8 bulls. Blood and electroejaculate were obtained simultaneously at 20, 40, 60, 120, and 180 minutes and 24 hours after bulls were injected to determine T3 and T4 concentrations compared with base-line values. Blood T3 and T4 concentrations were increased (P < 0.05) at 20 minutes after bulls were injected (1.1 ± 0.25 to 598 ± 76.3 ng/ml and from 66 ± 5 to 1,318 ± 105 ng/ml, respectively). Seminal concentrations of T4 were unchanged until 120 minutes after bulls were injected, when they increased (P < 0.05) from < 1.2 ng/ml to 4.7 ± 1.9 ng/ml. However, seminal concentrations of T3 were increased (P < 0.05) from < 0.1 ng/ml to 0.5 ± 0.2 ng/ml at 20 minutes and to 12.5 ± 2.9 ng/ml at 120 minutes after bulls were injected. It was concluded that exogenous thyroid hormones passed into the ejaculate from blood, with T3 passing faster than T4.
Porcine malignant hyperthermia: False negatives in the halothane test
Authors: Gallant Esther M. , Rempel William E. 
Published: February 2025

SUMMARY
Purebred Pietrain pigs presumed (on the basis of pedigree) to be homozygous for malignant hyperthermia (mh) susceptibility were subjected to a 3% halothane challenge test. A few (6%) pigs that should have been mh susceptible on the basis of parental genotype did not develop muscle rigidity in response to repeated halothane tests. Three of these animals were brought into the laboratory, and muscle biopsy specimens were obtained for in vitro analysis.
Bundles of intact muscle cells dissected from biopsy specimens were electrically stimulated, and mechanical responses were monitored during exposure to halothane. In all instances, the muscle bundles from the halothane-negative (ie, not sensitive to halothane), but genetically susceptible, pigs gave in vitro responses that were similar to those of halothane-positive mh-susceptible pigs in that tetanic tension was depressed, tetanus relaxation was slowed, and small contractures were produced upon halothane exposure. Thus, the presence of a halothane-sensitive abnormality in the skeletal muscles, in and of itself, is not always sufficient for development of in vivo muscle rigidity during a brief halothane test. Furthermore, when the halothane testing of pigs is conducted by recommended techniques, false negatives still occur in a small percentage of the genetically mh-susceptible animals.
Effect of electroejactuation on progesterone and Cortisol excretion in bovine semen
Authors: Eiler Hugo , Armstrong-Backus Cindy S. , Smalling John D. 
Published: February 2025

SUMMARY
Artificial vagina (av) and electroejaculation (ee) are the 2 methods used to obtain semen from bulls. The purpose in the present study was to evaluate these 2 methods of collection when 2 markers, Cortisol and progesterone, were injected iv.
During period 1 (control measurement), semen was obtained by ee at 0, 20, 60, 120, and 180 minutes. In period 2, bulls were injected (3 days later) with a mixture of Cortisol (113 mg) and progesterone (100 mg), and then samples were obtained by ee. In period 3, Cortisol and progesterone were injected (3 weeks later), and samples were obtained by av.
Seminal plasma concentrations of Cortisol and progesterone were maximal at 20 minutes in ee and av collections. Seminal plasma concentrations of progesterone and Cortisol were roughly 50% less in ee than in av collection. However, the total excretion of progesterone and Cortisol per collection was similar in both techniques. Excretion of Cortisol was 14 to 33 times greater than that of progesterone.
It was concluded that concentrations of markers in the ee were significantly less than those in av collection. For this reason, total excretion and concentration of marker in semen should be accounted for when conducting excretion studies.
Microsomal activation of constituents of white snakeroot (Eupatorium rugosum Houtt) to form toxic products
Authors: Beier Ross C. , Norman James O. , Irvin T. Rick , Witzel Donald A. 
Published: February 2025

SUMMARY
Components of white snakeroot, a plant toxic to livestock and human beings, were activated by Aroclor 1254-induced rat liver microsomes. The toxic products of microsomal activation were evaluated in murine melanoma (B16F1) cell cultures. Toxic products in white snakeroot were inactive in cell culture systems without microsomal activation. This activation system revealed that at least 2 fractions of white snakeroot were metabolically activated to cytotoxic agents. The autocatalytic inactivator of cytochrome P-450, 1-aminobenzotriazole, inhibited activation of white snakeroot constituents by rat liver microsomes.
Enzyme-linked immunosorbent assay for detection of Mycoplasma californicum-specific antibody in bovine serum: Optimization of assay determinants and control of serologic cross-reactions
Authors: Thomas C. B. , Jasper D. E. , Boothby J. T. , Dellinger J. D. 
Published: February 2025

SUMMARY
An enzyme-linked immunosorbent assay (elisa) was adapted to detect Mycoplasma californicum-specific antibodies in bovine serum. Cross-reactive antibody was found in the M californicum-positive reference serum when assayed against each of 7 solid-phase antigens of heterologous mycoplasma species. Cross-reactivity was further demonstrated by inhibition of elisa reactivity to M californicum solid-phase antigen by incubation of sera with antigen suspensions of each heterologous species. Incubation of test sera with a cross-reacting antigen mixture containing equal proportions of the 7 cross-reactive mycoplasmas was used to minimize cross-reactivity in the M californicum-specific elisa. Specificity of antibody reactivity to M californicum, as measured by elisa, was determined by enzyme-linked immunosorbance inhibition, in which sera were incubated with M californicum antigen suspensions before determining elisa reactivity to M californicum solid-phase antigen. Seropositive and suspect sera (n = 55) were obtained from 3 dairies that had bacteriologically verified epizootics of M californicum mastitis. The percentage of inhibition demonstrated in enzyme-linked immunosorbance inhibition was determined for each serum. Inhibition percentages below the 15th percentile (61% inhibition) of this distribution were classified as nonspecific.
Rectal transmission of bovine leukemia virus in cattle and sheep
Authors: Henry Edward T. , Levine Jay F. , Coggins Leroy 
Published: February 2025

SUMMARY
Bovine leukemia virus (blv) was transmitted by rectal inoculation of blv-infective whole blood into cattle and sheep. Two cows and 2 sheep each were given 500 ml and 50 ml of blood, respectively, by rectal infusion. Two sheep which served as positive controls each were given 1 ml of the same blood, iv. All animals became seropositive to blv by postinoculation week 5. Although relatively large volumes of blood were used for rectal inoculation, a base line for infectivity was established for the rectal route.
Effect of yohimbine on xylazine-induced hypoinsulinemia and hyperglycemia in mares
Authors: Greene S. A. , Thurmon J. C. , Tranquilli W. J. , Benson G. J. 
Published: February 2025

SUMMARY
Serum insulin and plasma glucose concentrations were determined in 8 mares. Four iv treatments were studied: (i) xylazine (1.1 mg/kg of body weight); (ii) yohimbine (0.125 mg/kg); (iii) yohimbine (0.125 mg/kg) followed 5 minutes later by xylazine (1.1 mg/kg); and (iv) 5 ml of isotonic saline solution as a control. Blood samples were collected before (time 0) and at 5, 15, 30, 60, 120, and 180 minutes after drug administration. Serum insulin concentration decreased and plasma glucose concentration increased in mares given xylazine. Plasma glucose concentration was unchanged in control mares and in mares given yohimbine or yohimbine followed by xylazine. Serum insulin concentration was unchanged in mares given saline solution, but transiently increased in mares given yohimbine alone. Treatment with yohimbine prevented xylazine-induced hypoinsulinemia and hyperglycemia.
Pharmacokinetics of single doses of phenobarbital given intravenously and orally to dogs
Authors: Pedersoli W. M. , Wike J. S. , Ravis W. R. 
Published: February 2025

SUMMARY
Pharmacokinetics of phenobarbital was studied in 10 healthy dogs after single iv or oral administration. Phenobarbital sodium was administered iv to 5 dogs in group A (5.5 mg/kg of body weight) and 5 dogs in group B (15 mg/kg). Serial venous blood samples (n = 21) were collected from each dog before (base line) and after the administration of phenobarbital sodium for pharmacokinetic evaluation. After a 30-day resting period, 3 dogs in group A and 3 in group B were randomly selected and used for an iv crossover treatment. The iv treatment mean half-life of phenobarbital sodium was 92.6 ± 23.7 and 72.3 ± 15.5 hours, whereas mean total clearance was 5.60 ± 2.31 and 6.66 ± 0.78 ml/hr/kg for doses of 5 and 15 mg/kg, respectively. The mean residence time was 124 ± 34 hours and 106 ± 23 hours for the 5.5 and 15 mg/ kg, iv doses, respectively. Significant differences (P > 0.05) were not observed in pharmacokinetic parameters between the 2-dose study.
After a 35-day resting period, dogs in groups A and B were treated as described for the single iv treatment, except that they were given a phenobarbital tablet orally. Serial venous blood samples (n = 24) were collected before (base line) and after the administration of phenobarbital. Mean bioavailability was 88.1 ± 12.4% and 96.8 ± 9.0%, half life of absorption was 0.263 ± 0.185 and 0.353 ± 0.443 hour, and lag time was 0.611 ± 0.683 and 0.741 ± 0.554 hour for groups A and B, respectively. A significant difference (P > 0.05) was not measured for these values between groups A and B.
Antimicrobial alternatives for calf diarrhea: Sera trace element responses to Escherichia coli-, deferoxamine-, or gallium-induced diarrhea
Authors: Fettman Martin J. , Brooks Patricia A. , Phillips Robert W. 
Published: February 2025

SUMMARY
Aseptic and septic inflammatory diseases often are associated with marked changes in tissue and sera trace element kinetics. Iron and zinc sequestration by the host may serve as a protective effect against microbial proliferation, but may deprive host tissues of these necessary elements as well. Conversely, systemic iron administration has been shown to increase susceptibility to, and severity of, infectious diseases, although deficient iron stores may be repleted. Escherichia coli enteritis in calves provides a model wherein the effects of enteric iron antagonism and parenteral iron supplementation may be studied simultaneously. Male calves (n = 12) were given (im injection) 300 mg of iron-dextran after base-line blood samples were obtained, then the calves were allotted to 4 groups (each of 3 calves): group 1 (control)—orally given nonpathogenic E coli; group 2—orally given enterotoxigenic B44 E coli; group 3—orally given deferoxamine (50 mg/kg, twice a day); group 4—orally given gallium (4 mg/ kg; twice a day). Calves were studied for 8 days; blood samples were obtained each day (day 1 through day 8) for hematologic and serum biochemical analyses. There were significant increases in serum iron concentration and % saturation in all calves within 24 hours of iron-dextran administration, which returned to base-line values in all but group 4 (given gallium) within 3 days. In the exceptional group (4), total iron-binding capacity decreased with time, as in the other groups, but serum iron concentration remained significantly increased, implying gallium interference with systemic iron assimilation. Serum Zn concentrations were decreased, and Cu concentrations increased in association with the onset of fever, diarrhea, and hypoglycemia in all treated groups (2, 3, and 4). Although mean corpuscular volume gradually decreased with time in all groups, there were no major treatment effects on hematologic variables (erythrocyte numbers or hemoglobin concentrations) during the study. Although the expected trace element responses to intestinal disease were seen in groups 3 (deferoxamine treatment) and 2 (given B44 E coli), gallium treatment (group 4) may have antagonized systemic iron kinetics without improving host response to disease.
Heterotransplantation of canine sarcoma cells (BLU284) in athymic (nude) mice
Authors: Aaronson Laura M. , Pardini Lani L. , Pardini Ronald S. 
Published: February 2025

SUMMARY
Undifferentiated canine sarcoma cells from a primary lesion were implanted subcutaneously in athymic (nude) mice. Tumors were implanted at 2 sites in each of 4 mice, and 6 of the 8 inoculation sites developed into tumors. Tumors grew and invaded surrounding tissues, as shown by histologic examination. Karyotype analysis verified that tumors were of canine origin. Cells from this tumor were serially heterotransplanted 26 times without consistent change in growth rate. Once established in nude mice, samples from 2 generations of this canine sarcoma cell line were stored cryogenically and were implanted into nude mice. Over 26 generations, 93.7% of fresh implants developed into tumors. Preliminary screening of antineoplastic drugs indicated that this tumor line was sensitive to cyclophosphamide and vincristine. The difference in sensitivity of this heterotransplanted tumor in nude mice toward the various antineoplastic agents provides a useful model for the elucidation of biochemical bases of antineoplastic drug resistance in tumors.
Gastric spirillosis in Beagles
Authors: Henry G. A. , Long P. H. , Burns J. L. , Charbonneau D. L. 
Published: February 2025

SUMMARY
Light microscopic, ultrastructural, and microbiologic evaluations were performed on stomachs from 30 healthy laboratory-reared Beagles. Spiral-shaped microorganisms were seen in the gastric glands and parietal cell canaliculi of all the dogs. Organisms were most numerous in the cardia and in the region of the fundic-pyloric junction. Lymphoreticular hyperplasia, dilatation of parietal cell canaliculi, and degeneration of individual parietal cells (rarely seen) were the only morphologic alterations seen. Organisms were helical, had tufts of flagella at each end, and were approximately 0.5 × 7.0 µm; some had a distinct axial fibril (indicating two distinct forms of the organism). Attempts to propagate a viable culture of the organism were not successful.
The organism most closely resembled those of the genus Spirillum. Because the organism was commonly found in the gastric mucosa of healthy Beagles, it probably should be considered part of the natural gastric flora of dogs.