bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concentrations of penicillin, streptomycin, and spiramycin in bovine udder tissue liquids
Authors: Franklin Anders , Horn af Rantzien Margareta , Obel Nils , Östensson Karin , Åström Göran 
Published: February 2025

SUMMARY
Concentrations of benzylpenicillin and spiramycin adipate were determined in bovine plasma and milk and in lymph draining the udder tissue after im or iv administration. Combined benzylpenicillin and dihydrostreptomycin sulfate concentrations were also determined in the same fluids after intramammary injection. A superficial parenchymal lymph vessel, afferrent to the supramammary lymph gland of the left quarters, was cannulated with a polythene catheter from which the lymph was allowed to drain freely. After injections of 9.5 mg of benzylpenicillin/kg of body weight im, a mean peak concentration (pc) in lymph (3.7 μg/ml), constituting 77% of the pc in plasma (4.8 μg/ml), was obtained 0.5 to 1 hour after pc in the plasma. The benzylpenicillin lymph concentration was close to that in plasma for about 7 hours after injection. Thereafter, the benzylpenicillin lymph concentration continued to exceed that in plasma, but not that in milk. After iv administration of spiramycin adipate, the lymph concentration was almost identical to that in plasma.
After intramammary injection of procaine benzylpenicillin (400 mg), in combination with the same amount of dihydrostreptomycin sulfate, into 2 udder quarters each, mean pc in the lymph of 3.5 μg/ml and 8.4 μg/ml, respectively, were obtained 6 hours after injection. In plasma, the mean pc of benzylpenicillin (0.07 μg/ml) and of dihydrostreptomycin sulfate (0.85 μg/ml) were obtained after 4 and 6 hours, respectively. In milk from the nontreated quarters, a mean concentration of 5 ng of benzylpenicillin/ml was obtained, whereas dihydrostreptomycin sulfate (≥ 0.3 μg/ml) was not detected. After administration of benzylpenicillin im or spiramycin adipate iv, concentrations of these drugs in the udder tissue extracellular fluid, the origin of the lymph of the cannulated vessels, were similar to the concentrations in plasma. After intramammary injection of procaine benzylpenicillin and dihydrostreptomycin sulfate, therapeutic concentrations of benzylpenicillin, but not of dihydrostreptomycin sulfate, were easily obtained in the udder tissue extracellular fluid.
Pharmacokinetics of single doses of gentamicin given by intravenous and intramuscular routes to lactating cows
Authors: Haddad Nadim S. , Ravis W. R. , Pedersoli W. M. , Carson R. L. 
Published: February 2025

SUMMARY
Healthy mature lactating cows (n = 6) were given gentamicin (5 mg/kg of body weight) by iv route and another dose 19 days later by im route. Serum gentamicin concentrations were determined over a period of 48 hours after each drug dosing, using radioimmunoassay. With the aid of a nonlinear least-square regression analysis program, the combined data of the iv and im treatments were best fitted by a 2-compartment open model, as indicated by residual trends and improvements in the sum of squares by F test and the sd of the estimated values. The distribution phase half-life was 0.25 ± 0.12 hour, and postdistribution half-life was 1.83 ± 0.18 hours. The volume of the central compartment was 0.10 ± 0.02 L/kg, volume of distribution at steady state was 0.16 ± 0.03 L/kg, and the total body clearance was 1.32 ± 0.17 ml/min/kg.
Intramuscular absorption was rapid, with a half-life for absorption of 0.63 ± 0.28 hour. The extent of im absorption was 92% ± 15%. The percentage of the im dose eliminated in the urine during the first 8 hours was 83 ± 8. Gentamicin was detected in milk for 48 hours. Kinetic calculations predicted that im injection of gentamicin at a dosage of 3.5 mg/kg of body weight every 8 hours would provide average steady-state serum drug concentrations of 5.08 μg/ml, with minimum and maximum steady-state concentrations of 1.03 and 12.05 μg/ml, respectively, whereas an im injection of a 5 mg/kg dosage every 8 hours would provide average steady-state serum concentrations of 7.26 μg/ml, with minimum and maximum steady-state serum concentrations of 1.47 and 17.21 μg/ml, respectively.
Evaluation of terminal deoxynucleotidyl transferase expression in bone marrow of clinically normal and feline leukemia virus-exposed cats
Authors: Lafrado Louis J. , Mathes Lawrence E. , Olsen Richard G. 
Published: February 2025

SUMMARY
Bone marrow cells from 8 specific-pathogen-free and 11 feline leukemia virus-exposed cats were examined for the expression of the nuclear antigen terminal deoxynucleotidyl transferase (TdT). Using a standard indirect immunofluorescence technique, feline leukemia-exposed cats had increased expression of TdT in bone marrow aspirates (2.0% to 29.0%) when compared with that in bone marrow cells from specific-pathogen-free cats (2.5% to 6.0%). Seemingly, TdT can be used as an antigenic marker in leukemogenesis of FeLV-infected cats.
Multielement assays of canine serum, liver, and kidney by inductively coupled argon plasma emission spectroscopy
Authors: Stowe Howard D. , Braselton W. Emmett , Slanker Michael , Kaneene John B. 
Published: February 2025

SUMMARY
Inductively coupled argon plasma emission spectroscopy was used to measure Al, As, Ca, Cd, Cr, Cu, Fe, Pb, Mg, Mn, Hg, Mo, Ρ, Κ, Se, Na, Tl, and Zn in canine specimens (70 serum, 270 liver, and 200 kidney). Mean concentrations of each of these elements in detectable amounts in these samples were established, and histograms of the concentration distributions of elements in the samples were developed.
Location of the instantaneous center of joint rotation in the normal canine stifle
Authors: Ireland W. P. , Rogers J. , Myers R. K. 
Published: February 2025

SUMMARY
Locations of 3 instantaneous centers of joint rotation (icr) were found in the stifles of 6 healthy dogs. A novel algorithm, verified by computer simulation, was used to determine icr from radiographs. Comparisons of icr locations were made between flexion and extension, between left and right limbs, and between living and dead dogs, using analysis of variance. All stifles were examined for evidence of lesions, but all were normal. The normal location of the icr in the stifle is near the joint surface, indicating that there is a predominantly rolling type of motion. As the limb flexes, the icr moves caudally; as the limb extends, the icr moves cranially. Significant differences in icr position were not found between left and right limbs or between living and dead dogs. The average icr position was significantly more caudal during extension than it was during flexion. Knowing the normal icr position is a preliminary to diagnosing joint abnormalities, using the icr.
Decreased complement and bacteriostatic activities in the sera of cattle given single or multiple doses of aflatoxin
Authors: Thurston John R. , Cook William , Driftmier Kim , Richard John L. , Sacks Jerome M. 
Published: February 2025

SUMMARY
Five steers given 1 dose of partially purified aflatoxin at concentrations sufficient to provide 0.2 mg to 0.8 mg of aflatoxin B1 equivalents/kg of body weight were compared with 4 steers given 14 daily doses of 0.25 mg of aflatoxin B1 equivalents/kg of body weight for complement activity and bacteriostasis. Complement activity was measured by hemolysis in gel, and bacteriostatic activity, by growth inhibition of Escherichia coli in liquid medium. In the single-dose group, complement activity and bacteriostatic activities decreased by 57 hours after dosing, and both returned to near base line by 168 hours. In the daily dose group, only bacteriostatic activity decreased, and the decrease persisted 2 weeks after the last dose of aflatoxin was given. Apparently, aflatoxin affects both complement-dependent and independent serum bacteriostatic activity.
Neutrophil Chemotaxis in rhesus macaques (Macaca mulatta)
Authors: Gonder J. C. , Thomas J. M. , Payne E. S. 
Published: February 2025

SUMMARY
Chemotactic responses of isolated peripheral blood neutrophils from rhesus macaques (Macaca mulatta) were studied, using a micropore filter method. Cell migration toward zymosan-activated serum was similar to that of human cells, whereas the response to N-formyl methionyl leucyl phenylalanine (fmlp) was weaker than was that in human cells, requiring higher concentrations of fmlp for maximal migration. Optimal fmlp concentrations for attraction of rhesus neutrophils and human neutrophils were 5.0 × 10−7M and 1.0 × 10−8M, respectively. The chemotactic responses of the 2 neutrophils to complement (zymosan-activated serum) were similar. However, rhesus neutrophils required a higher concentration of the formyl peptide, fmlp, for maximal migratory response.
Screen for anthelmintics, using larvae of Ascaris suum
Authors: Rew R. S. , Urban J. F. , Douvres F. W. 
Published: February 2025

SUMMARY
A multiwell culture system was used to assay the effects of 12 known anthelmintic compounds on Ascaris suum larval development from 2nd-stage (L2; hatched from eggs) to early 3rd-stage (L3) and from in vivo-derived late L3 to early 4th-stage (L4). Larval survival, development, and motility were monitored for drug effects. Development of L2 to L3 was sensitive to thiabendazole, albendazole (abz), abz/sulfoxide, abz/sulfone (so), mebendazole, l-tetramisole, d-tetramisole, piperazine, or closantel at a concentration of 0.01 μg/ml; however, the effects of these drugs on larval development did not correlate well with known effects in vivo. The development of L3 to L4 was blocked by abz or mebendazole at 0.01 μg/ml, by thiabendazole or abz/sulfoxide at 0.1 μg/ml, and by abz/so at 1.0 μg/ml; however, except for abz/so, most larvae were viable at these concentrations. In contrast, l-tetramisole or morantel appeared to inhibit development of L3 to L4 and to reduce survival at concentrations of ≥ 1 μg/ml; however, d-tetramisole was at least 10 times less effective. Haloxon, ivermectin, and closantel blocked development of L3 to L4 at 0.1, 1, and 10 μg/ml, respectively, in the absence of serum, but their activity was reduced by the presence of serum. Seemingly, in vitro development of A suum larvae was a convenient and sensitive bioassay for anthelmintic activity and could serve as a screen for anthelmintic residues in edible tissues.
Experimental Cryptosporidium infections in chickens: Oocyst structure and tissue specificity
Authors: Lindsay David S. , Blagburn Byron L. , Sundermann Christine A. , Hoerr Frederic J. , Ernest James A. 
Published: February 2025

SUMMARY
Oocysts of an avian isolate of Cryptosporidium were used to inoculate 21 chicks orally and 7 chicks intratracheally to determine the tissue specificity of this organism. Oocysts were passed in the feces 4 to 5 days after inoculation. Oocysts (6.8 by 5.0 μm) were fully sporulated and they were passed for at least 17 days by infected chicks. The mode of inoculation did not influence the distribution of cryptosporidia within the digestive tract. Cryptosporidia were found in the cloaca (100%), bursa of Fabricius (95.7%), terminal portion of the colon (26.1%), and cecum (4.3%) of chicks that were positive for developmental stages. Of 21 chicks inoculated orally, 4 had cryptosporidia in their trachea, whereas 6 of 7 chicks inoculated intratracheally had cryptosporidia in the trachea, bronchi, and air sacs. Cryptosporidium was found in the ducts of the salivary glands and nasal turbinates of chicks inoculated intratracheally that had clinical signs of respiratory tract disease. None of the chicks died or had intestinal disease.
Onchocerca spp: Frequency in Thoroughbreds at necropsy in Kentucky
Authors: Lyons Ε. T. , Tolliver S. C. , Drudge J. H. , Swerczek T. W. , Crowe M. W. 
Published: February 2025

SUMMARY
Examination of the ligamentum nuchae for Onchocerca spp was completed in 523 Thoroughbreds (1 to 29 years old) at necropsy in Kentucky during a 13-month period (1984 to 1985). Onchocerca spp were found in 306 (59%) of the horses. Frequencies of this parasite were 3%, 17%, 40%, 43%, and 42% in 1-, 2-, 3-, 4-, and 5-year-old horses, respectively. For 6- to 29-year-old horses, frequency varied from 71% to 100%, except for 26-year-old horses (50%); 87% of the 304 horses examined in the 6- to 29-year-old age groups was infected.
The suspensory ligaments and flexor tendons from fetlocks (thoracic limb only) of 100 Thoroughbreds (3 to 24 years old) were examined at necropsy during a 4-month period (1984) for Onchocerca spp. Infected horses were not found.
Infectious bovine keratoconjunctivitis: Evidence for genetic modulation of resistance in purebred Hereford cattle
Authors: Pugh George W. , McDonald Timothy J. , Kopecky Kenneth E. , Kvasnicka William G. 
Published: February 2025

SUMMARY
A vaccination study was conducted in a herd of purebred Hereford cattle representing 4 selection (genetic) lines. For each of 2 years, half of the cattle were vaccinated with a pilus-enriched Moraxella bovis bacterin. Cows were vaccinated before parturition, and calves were vaccinated at 2 to 3 months of age. None of the cattle was vaccinated for 1 year preceding and 1 year after the 2 years in which cattle were vaccinated.
There was a significantly (P < 0.05) lower percentage of infectious bovine keratoconjunctivitis (ibk) in calves during years cattle were vaccinated than during years cattle were not vaccinated. During years cattle were vaccinated, there were lower percentages of ibk in vaccinated calves when compared with the percentages of ibk in nonvaccinated calves. When calves were compared on the basis of selection lines, regardless of the vaccination group, there were consistent differences in the percentages that developed ibk. Although calves with pigmented and nonpigmented eyes (representing all 4 genetic lines) developed ibk, the genetic line of calves with the most pigmented eyes had the lowest (P < 0.05) percentage of ibk. Also, across all genetic lines, there was less ibk in pigmented eyes than in nonpigmented eyes.
Seemingly, vaccination of dams, before parturition, and young calves reduced the occurrence of severe ibk in a herd situation under natural exposure conditions. The resistance or susceptibility in cattle under good management may be influenced by genetic factors.
Antithrombin III activity in horses with large colon torsion
Authors: Holland Melissa , Kelly Andrew B. , Snyder Jack R. , Steffey Eugene P. , Willits Neil , McNeal Dale 
Published: February 2025

SUMMARY
A chromogenic peptide substrate assay was used to determine serially plasma antithrombin III (AT III) activity in 4 groups of horses. Group I consisted of healthy, mature horses in which AT III activity was determined twice daily for 7 consecutive days. Groups 2 and 3 contained healthy horses in which AT III activity was monitored for 7 days after controlled, but varying, conditions of general anesthesia and surgery (median celiotomy). Group 4 was made up of patients with a presurgical diagnosis of colonic torsion. In healthy awake horses (group I), there was no difference in AT III values over time. Postoperative AT III activity in the halothane-anesthetized horses (group 2) and in the sham-operated horses (group 3) was not significantly (P = 0.05) different from base-line values at any time. A significant decrease (P = 0.05) in AT III activity was observed on postoperative days 1 through 3 in the group of horses with large colon torsion, but returned to preoperative values by day 4 after surgery in the horses that survived. In those horses that did not survive, AT III activity remained below base-line values for the duration of observation. Seemingly, plasma AT III activity in horses was not significantly affected by halothane anesthesia or surgery. Serial evaluation of AT III activity may be useful for predicting survival in horses with large colon torsion.
Effects of phenobarbital treatment on 3-methylindole toxicosis in ponies
Authors: Turk Margaret A. M. , Thomas David E. 
Published: February 2025

SUMMARY
To study the role of cytochrome P-450-dependent mixed function oxidase reactions in equine 3-methylindole (3MI) toxicosis, ponies were given 20 mg of phenobarbital/kg of body weight at 72, 60, 48, 36, and 24 hours before 100 mg of oral 3MI/kg to induce cytochrome P-450 or no treatment (controls). Maximal 3MI plasma concentration was decreased and clearance was faster in phenobarbital-treated ponies. Plasma 3MI was still detectable 12 and 36 hours after dosing in phenobarbital-treated and control ponies, respectively. Phenobarbital treatment induced a distribution phase with transition from a 1-compartment to a 2-compartment extravascular model. Bronchiolitis occurred in all ponies 72 hours after 3MI, but was more severe in those treated with phenobarbital. Appearance of a distribution phase, increased total body clearance, and more severe bronchiolitis in phenobarbital-treated ponies indicated that mixed function oxidases are involved in metabolism and conversion of 3MI to a toxic metabolite.
Effects of radiofrequency hyperthermia on the healthy canine cornea
Authors: Glaze Mary B. , Turk Margaret A. M. 
Published: February 2025

SUMMARY
Radiofrequency hyperthermia was used to induce axial corneal lesions in the eyes of 10 dogs. Clinical observations were continued for up to 6 months, using biomicroscopy and indirect ophthalmoscopy, Eyes were harvested at intervals for light and electron microscopic evaluation.
Clinical alterations included immediate corneal opacification and epithelial disruption at the site of electrode contact. Ulcerative keratitis persisted for 4 to 6 days, accompanied by anterior uveitis. Additional corneal changes included stromal thinning, edema, and vascularization. Final evaluation revealed negligible alterations in corneal contour or clarity 6 months after treatment.
Microscopically, epithelial and superficial stromal necrosis preceded epithelial loss. Stromal alterations included edema (associated with focal endothelial detachments), vascularization, and inflammatory cell infiltration. Recovery was characterized by keratocytic hyperplasia and hypertrophy, epithelial proliferation, and stromal condensation.
Chicken embryonal vaccination with avian infectious bronchitis virus
Authors: Wakenell P. S. , Sharma J. M. 
Published: February 2025

SUMMARY
A commercial infectious bronchitis virus (ibv) vaccine of the Massachusetts 41 strain was injected in embryonating chicken eggs on embryonation day (ed) 18. The ibv vaccine was pathogenic for embryos, and it was passaged in chicken kidney tissue culture to reduce the pathogenicity. At the 40th tissue culture passage (P40-ibv), the virus became apathogenic for the embryos. Maternal antibody-positive or -negative chicks hatching from eggs injected with P40-ibv developed antibody to ibv and were protected against challenge exposure at 4 weeks of age with virulent Massachusetts 41 ibv. Although P40-ibv protected chicks when administered on ed 18, this virus did not protect chicks well if given at hatch. When combined with the turkey herpesvirus (hvt), P40-ibv given on ed 18 did not interfere with the protection against challenge exposure with virulent Marek's disease virus, nor did the presence of hvt interfere with protection by P40-ibv. Thus, under laboratory conditions, ibv vaccine could be combined with hvt to form a bivalent embryonal vaccine.
Effects of small and large face masks and translaryngeal and tracheostomy intubation on ventilation, upper-airway dead space, and arterial blood gases
Authors: Haskins Steve C. , Patz John D. 
Published: February 2025

SUMMARY
Pulmonary function was examined in pentobarbital-anesthetized dogs that were spontaneously breathing through a large poorly fitted face mask, a small snug-fitted face mask, an endotracheal tube, and a tracheostomy tube. Increasing upper-airway dead space volumes were associated with higher minute ventilation and faster breathing rates. Minute and tidal alveolar ventilation, calculated ideal alveolar oxygen, alveolar-arterial oxygen gradient, venous admixture, arterial pH and blood gases, cardiac output, and systemic and pulmonary arterial blood pressure were not changed.
The functional dead space of each mask was considerably less than that measured by water displacement. The small mask only slightly increased, and the endotracheal tube slightly decreased, the dead space estimated for a nasally breathing healthy dog.
DNA homology studies of leptospires of serogroups Sejroe and Pomona from cattle and swine
Authors: Le Febvre Rance B. , Thiermann Alex B. 
Published: February 2025

SUMMARY
Hybridization studies of chromosomal DNA from leptospiral strains representing Leptospira interrogans, serogroups Sejroe and Pomona from cattle and swine were performed to determine the degree of homology among their DNA sequences. Chromosomal DNA isolated from leptospires of the Sejroe and Pomona serogroups was radiolabeled and used to probe DNA isolated from other strains in these serogroups. Serovars hardjo (hardjoprajitno), hardjo (hardjo-bovis), balcanica (1627 Burgas), pomona (pomona), and kennewicki (LT-1026) were probed to determine the degree of homology among their chromosomes. Serovars pomona and kennewicki were homologous to each other. They also had a high degree of homology with hardjo (hardjoprajitno) and, to a lesser extent, with hardjo (hardjo-bovis) strains. However, hardjoprajitno and hardjo-bovis had little homology to each other. Serovar balcanica had a high degree of homology with hardjo-bovis isolates, but little homology with hardjoprajitno. Although serologically indistinguishable, the reference strain hardjoprajitno was genetically dissimilar to hardjo-bovis strains isolated from North American cattle.
Lymphangiographic evaluation of experimentally induced chylothorax after ligation of the cranial vena cava in dogs
Authors: Fossum Theresa W. , Birchard Stephen J. 
Published: February 2025

SUMMARY
Ligation of the cranial vena cava (CrVC) distal to the entrance of the azygous vein resulted in chylothorax in 7 of 10 dogs. Of the remaining 3 dogs, 1 developed a serosanguineous effusion that did not become chylous, and 2 dogs did not develop pleural effusion. In 2 of the 7 dogs developing chylothorax, the pleural effusion became serosanguineous within 2.5 weeks after CrVC ligation. Mesenteric lymphangiography was performed 2 to 6 weeks after ligation of the CrVC. Lymphangiectasia was seen in 4 dogs with chylothorax, but was not seen in the 3 dogs with serosanguineous effusions or the 2 dogs that did not develop effusions. One dog with chylothorax died prior to repeat lymphangiography. Less dye entered the thoracic duct, and alternate lymphaticovenous communications to the caudal vena cava were evident in the dogs without chylothorax.
Ligation of the thoracic duct at the lymphaticovenous junction was performed in 3 dogs. These dogs did not develop pleural effusion. Lymphangiography was performed immediately after ligation and indicated filling of abdominal lymphatics but not of the thoracic duct. Lymphangiographic findings 6 weeks after ligation also indicated filling of intestinal lymphatics.
Results of the present study indicated that ligation of the CrVC causes chylothorax, and that thoracic lymphangiectasia is a consistent finding in animals with experimental chylothorax. Obstruction of the thoracic duct did not induce lymphangiectasia or chylothorax. Impedence of thoracic duct flow into the CrVC may be a cause of clinical chylothorax in the dog.
Gastric emptying of liquids in the dog: Effect of volume
Authors: Leib Michael S. , Wingfield Wayne E. , Twedt David C. , Williams Anne R. 
Published: February 2025

SUMMARY
Effect of liquid test meal volume on gastric emptying was investigated in healthy nonoperated dogs fed meal sizes of 6.6 to 110 ml/kg of body weight. For meals ≤ 66 ml/kg, the amount of test meal emptied from the stomach in 30 minutes vs meal size could be described as following a linear, exponential, or square root pattern. Deviation from these patterns was seen with test meals of 77, 88, and 110 ml/kg. A mean ± sem maximum of 0.99 ± 0.06 ml/kg/min of liquid test meal was emptied from the stomach of dogs fed test meals of 77, 88, and 110 ml/kg. Massive gastric distension induced in dogs during this study did not alter gastric emptying of the liquid test meal.