bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro platelet release by rat megakaryocytes: Effect of metabolic inhibitors and cytoskeletal disrupting agents
Authors: Handagama P. J. , Feldman B. F. , Jain N. C. , Farver T. B. , Kono C. S. 
Published: February 2025

SUMMARY
Development of an in vitro visual assay facilitated the study of large numbers of megakaryocytes undergoing proplatelet formation in short-term cultures. Approximately 9% of megakaryocytes formed platelets during a 24-hour period. In the presence of an inhibitor of anaerobic glycolysis (NaF), proplatelet formation was inhibited, whereas inhibitors of respiration (NaCN) did not significantly (P > 0.05) decrease proplatelet formation. Presence of the microtubule-disrupting agents colchicine and vincristine sulfate in culture medium inhibited proplatelet formation, whereas the microfilament-disrupting agent cytochalasin B had a less pronounced inhibition.
N-Acetyl-β-D-glucosaminidase activities, milk somatic cell counts, and blood leukocyte and erythrocyte counts in cows after heat-induced stress or after intravenous administration of adrenocorticotropic hormone
Authors: Berning L. M. , Paape M. J. , Miller R. H. , LeDane R. A. 
Published: February 2025

SUMMARY
Six midlactation, nonpregnant cows were subjected to heat-induced stress or to repeated injections of adrenocorticotropic hormone (acth). The heat stress (experiment 1) consisted of subjecting the cows to 7 days of fluctuating temperatures (21 C during the day, 32 C during the night). The acth-induced stress (experiment 2) was accomplished by giving each of the cows 100 IU of acth twice daily for 4 consecutive days. The cows' milk somatic cell counts (mscc), milk N-acetyl-β-d-glucosaminidase (NAGase) activity, quarter milk production (ie, milk production per mammary quarter), blood leukocyte counts, and plasma concentrations of NAGase were monitored in both experiments. Although heat stress did not result in significant differences in NAGase, heat stress did significantly (P < 0.05) decrease milk production.
The acth administrations resulted in increased milk NAGase activity, mscc, and blood leukocyte counts, and in decreased plasma NAGase activity and quarter milk production. Therefore, milk NAGase activity and Msec were not affected by short-term heat stress, but were increased by acth-induced stress. Blood erythrocyte concentrations were not affected by heat stress or by acth-induced stress.
Immunologic memory responses induced in BALB/c mice by cross-linked outer membrane extracts of four Salmonella serotypes
Authors: Kudrna David A. , Teresa George W. , Arnzen Jeanene M. , Beard K. Scott , Olson Deborah 
Published: February 2025

SUMMARY
Outer membrane proteins (omp), extracted from Salmonella enteritidis, S anatum, S typhimurium, and S infantis, were cross-linked to form a large immunogen (4-omp-lipopolysaccharide [lps]). Vaccinations with 4-omp-lps dissolved in phosphate-buffered saline solution and 4-omp-lps emulsified with muramyl dipeptide were capable of eliciting specific and sustained primary IgM and IgG responses in BALB/c mice, as well as inducing immunologic memory for 130 days. In addition to 4-omp-lps-specific responses, substantial IgM and IgG responses specific for each live homologous organism were detected over the 130-day trial. In comparison with vaccination with 4-omp-lps dissolved in phosphate-buffered saline solution, responses specific for the antigen or the homologous Salmonella were not markedly increased in mice vaccinated with 4-omp-lps emulsified with muramyl dipeptide. Seemingly, cross-linked omp, without the inclusion of muramyl dipeptide, may have potential as vaccine components and may induce immunologic memory.
Compound-action potentials of myelinated fibers in the saphenous nerve of the dog: In situ electrophysiologic and behavioral studies
Authors: Whalen L. R. , Spurgeon T. L. , Boggie L. C. 
Published: February 2025

SUMMARY
Compound-action potentials (cap) were recorded directly from the surface of fascicles of the distal portion of the saphenous nerve (sn) of dogs in situ. Potentials were evoked through needle electrodes and were recorded through bipolar stainless steel electrodes.
Stimuli of 10-μs duration and of 0.4 ± 0.15-mA amplitude evoked a monophasic cap. Sensory conduction velocities of afferent fibers, the action potentials of which contributed to this evoked compound potential, ranged from 62.4 ± 2.8 m/s for the most rapidly conducting fibers to 30.5 ± 2.4 m/s for the least rapidly conducting fibers. Stimuli of 25-μs duration and of 2.2 ± 0.8-mA amplitude evoked a second, longer latency cap in addition to the first cap. Sensory conduction velocities of afferent fibers, the action potentials of which contributed to this evoked compound potential, ranged from 20.4 ± 2.9 m/s for the most rapidly conducting fibers to 13.7 ± 1.0 m/s for the least rapidly conducting fibers. Low-amplitude, negative peaks were recorded between the first and second major potentials elicited by the longer duration stimuli. Stimuli of still longer duration and higher currents induced contractions of the caudal part of the sartorius muscle by current spread in 9 of 12 dogs. In 3 dogs, a third monophasic cap was evoked, having a maximal conduction velocity of 1.7 ± 0.2 m/s.
After section of the distal portion of the sn on one side in each of 2 dogs, an absence of signs of sensory deficit was found on clinical neurologic examination. The area of cutaneous innervation of the cranial branch of the distal portion of the sn was determined electrophysiologically.
Seasonal occurrence and distribution of Gasterophilus intestinalis and Gasterophilus nasalis in the stomachs of equids in Texas
Authors: Price R. E. , Stromberg P. C. 
Published: February 2025

SUMMARY
Stomachs of 271 horses and ponies from 2 sources were evaluated for the presence of Gasterophilus intestinalis and G nasalis larvae, through 2 overlapping 12-month periods of bot fly activity in southern Texas. Equids (n = 140) from one source had nearly 96% of their stomachs infected, whereas equids (n = 131) from another source had 44% of their stomachs infected by Gasterophilus spp.
Seasonal dynamics of the bot infection indicated the highest average number of bot larvae per infected stomach occurred in the winter and spring. The smallest average number of bots per infected stomach occurred in the fall. Higher percentages of early (2nd instar plus young 3rd instar) larvae of G intestinalis were observed in the fall in equids from both sources. The late (more fully developed older 3rd instar) G intestinalis larvae outnumbered the early larvae in the winter, spring, and summer. Seasonal variation in numbers and development status of the larvae was consistent with the largest period of adult bot fly activity occurring during the fall.
The 2 species of bots had different predilection sites of attachment. Gasterophilus intestinalis larvae concentrated in the nonglandular portions of the stomach near the margo plicatus on the cranial (parietal) surface of the stomach and in the most dorsal extent of the saccus cecus. Gasterophilus nasalis larvae attached almost exclusively in the first ampulla of the duodenum. Predilection sites for both Gasterophilus spp occurred in dorsally positioned areas in the alimentary tract favoring increased availability of oxygen.
Pharmacokinetics and interactions of digoxin with phenobarbital in dogs
Authors: Ravis W. R. , Pedersoli W. M. , Turco J. D. 
Published: February 2025

SUMMARY
In one experiment, 5 dogs were administered digoxin (0.022 mg/kg of body weight, iv), were rested for 2 weeks, were then given phenobarbital (13.2 mg/kg orally) for 14 days, and then were given digoxin again (0.022 mg/kg, iv). Comparing prephenobarbital (control) digoxin half-lives of 42.4 ± 8.8 hours and postphenobarbital digoxin half-lives of 18.0 ± 2.2 hours, the half-life was significantly (P < 0.05) decreased after phenobarbital administration. Clearance was increased by 84%, and the volume of distribution given was decreased by 34%.
In a second experiment, 5 dogs were given digoxin (0.022 mg/kg, orally) daily for 11 days, and the digoxin kinetics were evaluated after the last dosing. The dogs were then rested and given phenobarbital (13.2 mg/kg, orally) once daily for 14 days and digoxin (0.022 mg/kg) once daily for 11 days, and the pharmacokinetics of digoxin was determined on the last day of dosing. Significant differences in steady-state serum concentrations and the pharmacokinetics of digoxin were not found between the control and phenobarbital phases of the experiment. Mean (± SD) half-lives of digoxin were 29.0 ± 7.2 hours before phenobarbital treatment (control) and were 34.8 ± 7.2 hours after phenobarbital treatment.
In comparing results of the single-dose experiment vs the oral multiple-dose experiment, dogs had shorter half-lives for digoxin after multiple dosing. Therefore, if phenobarbital and digoxin are to be chronically coadministered orally, an adjustment in the digoxin dose is not necessary.
Pharmacokinetics of phenolsulfonphthalein in horse and pony mares
Authors: Hinchcliff Kenneth W. , McGuirk Sheila M. , MacWilliams Peter S. 
Published: February 2025

SUMMARY
Pharmacokinetics of phenolsulfonphthalein (psp) in horse and pony mares was determined after injection of 1 mg/kg of body weight, iv. A plasma psp concentration vs time curve was described adequately in horses and ponies by an open, 2-compartment model. There were significant differences in the elimination phase parameters, apparent volume of distribution at steady state, and apparent volume of distribution of horses and ponies. The harmonic mean elimination half-life of psp in horses was significantly longer (P < 0.001) than that in the ponies (16.4 and 10.0 minutes, respectively). The mean plasma clearance of psp in horses was significantly (P < 0.05) less than that in ponies (0.00554 and 0.00701 L/min/kg, respectively). There was no difference between horses and ponies in the metabolic clearance of psp. The fraction of the administered dose of psp excreted in the urine in the first 15 minutes was not significantly different between horses and ponies.
Pharmacokinetics of oxytetracycline hydrochloride in rabbits
Authors: McElroy Donita E. , Ravis William R. , Clark Carl H. 
Published: February 2025

SUMMARY
Pharmacokinetics of oxytetracycline HCl (otc) was studied in rabbits. After 10 mg of otc/kg of body weight was administered iv, the distribution half-life was 0.06 hour, terminal half-life was 1.32 hours, volume of distribution area was 0.861 L/kg, and total body clearance was 0.434 L/kg/h. After 10 mg of otc/kg was given im, the absorption half-life was 2.09 hours, extent of absorption was 71.4%, and total body clearance of the absorbed fraction was 0.576 L/kg/h. Based on these kinetic data, a dosage of 15 mg of otc/kg, every 8 hours was developed. This dose given im for 7 consecutive days resulted in observed steady-state maximum and minimum concentrations (mean ± sd) of 4.7 ± 0.3 μg/ml and 3.2 ± 0.6 μg/ml, respectively. Twice this dose (30 mg of otc/kg, every 8 hours) given im caused anorexia and diarrhea.
Canine distemper virus-induced thrombocytopenia
Authors: Axthelm Michael K. , Krakowka Steven 
Published: February 2025

SUMMARY
Effects of canine distemper virus (cdv) infection on circulating platelet values were studied in gnotobiotic dogs inoculated with R252-cdv. Thrombocytopenia (< 200,000 platelets/μl) was present on postinoculation day (pid) 5 and persisted through pid 15. Peak thrombocytopenia occurred on pid 10 (< 85,000 platelets/μl). Thrombocytopenia was accompanied by lymphopenia, neutropenia, and monocytopenia. Platelet membrane-bound cdv antigen and IgG were present from pid 7 onward; neither the third component of complement nor IgM was detected on platelets from cdv-inoculated dogs. The mean number of megakaryocytes per unit of bone marrow surface area was unchanged. Megakaryocyte infection was present in dogs euthanatized on pid 4 (0.33%), increased slightly in dogs euthanatized on pid 8 (3%), and increased sharply in dogs euthanatized on pid 9 and 10 to 17.8% and 8.3%, respectively. Phagocytosis of platelets by stellate reticuloendothelial (Kupffer's) cells in the liver was prominent in dogs euthanatized from pid 5 onward. Seemingly, cdv-induced thrombocytopenia was mediated by virus-antibody immune complexes on platelet membranes. Decreased platelet production after pid 8 resulting from direct viral infection of megakaryocytes was a likely contributing factor and occurred against a background of profound virus-induced dysfunctions of all hematopoietic cellular elements.
Effect of RA233 on metastasis in dogs with osteosarcomas
Authors: Hamilton Helen B. , LaRue Susan M. , Withrow Stephen J. 
Published: February 2025

SUMMARY
The influence of RA233, an inhibitor of platelet function, on the occurrence of metastasis in 18 dogs with osteosarcomas was evaluated. At feast 24 hours before surgical removal of the primary tumor, dogs were given RA233 orally (20 mg/kg of body weight divided into 3 equal doses).
Original sites of the osteosarcoma included humerus, 6 dogs; radius, 5 dogs; tibia, 3 dogs; femur, 2 dogs; maxilla, 1 dog; and mandible, 1 dog. Survival time for 13 dogs euthanatized for progression of neoplastic disease ranged from 3 months to 10 months, with a mean survival time of 5.5 months. Medication was discontinued in 1 dog because of possible adverse reaction. One dog died of disease unrelated to the tumor, and one dog was euthanatized after the surgery. Two dogs were tumor free 9 and 17 months after surgery. Seemingly, the metastasis potential was not diminished in dogs given 20 mg of RA233/kg/day.
Comparisons of feline panleukopenia virus, canine parvovirus, raccoon parvovirus, and mink enteritis virus and their pathogenicity for mink and ferrets
Authors: Parrish Colin R. , Leathers Charles W. , Pearson Renee , Gorham John R. 
Published: February 2025

SUMMARY
Parvoviruses from mink (mink enteritis virus [mev]), cats (feline panleukopenia virus [fpv]), raccoons (raccoon parvovirus [rpv]), and dogs (canine parvovirus [cpv]) were compared. Restriction enzyme analysis of the viral rep-licative-form dna revealed no consistent differences between fpv and rpv isolates, but cpv and mev isolates could be distinguished readily from other virus types.
Feline panleukopenia virus, rpv, and mev, but not cpv, replicated to high titers in mink. However, on the first passage, disease and microscopic lesions were observed only in mink inoculated with mev. Feline panleukopenia virus and rpv isolates replicated in ferrets, but disease or microscopic lesions were not observed. Feline panleukopenia virus and rpv isolates could be passaged repeatedly in mink and ferrets. Virulence of fpv and rpv isolates was low compared with that of mev, and only a single mink inoculated with fpv or with rpv developed clinical disease on the sixth passage of virus.
Antibodies to spotted fever-group rickettsiae in dogs in North Carolina
Authors: Breitschwerdt Edward B. , Moncol Daniel J. , Corbett Wayne T. , MacCormack J. Newton , Burgdorfer Willy , Ford Richard B. , Levy Michael G. 
Published: February 2025

SUMMARY
A seroepidemiologic survey was conducted to determine the prevalence of antibodies reactive with 4 spotted fever-group (sfg) rickettsiae in sera of dogs from various geographic regions in North Carolina. Serum specimens were obtained from 600 dogs, and antibody titers were determined, using microimmunofluorescence. Data analysis (setting as the criterion for a positive result, a Rickettsia rickettsii titer ≥ 1:64) overestimated the actual prevalence of canine exposure to this rickettsia. When data were analyzed by considering each dog's serologic response to all 4 rickettsial antigens simultaneously, the prevalence rate for exposure to R montana was 15%, to R rhipicephali was 11%, and to R rickettsii was 5%. A definitive exposure to R bellii was not observed, and the identification of the specific inciting rickettsia could not be established for 13% of the dogs, because of identical highest titers to 2 or more antigens.
Our data indicate that canine exposure to R rhipicephali is prevalent in the eastern coastal region, whereas exposure to R montana takes place uniformly throughout the state. Rickettsia rickettsii exposure appears to be more prevalent in the central Piedmont region, but rarely is encountered in the western mountains. Regional sero-prevalence for canine R rickettsii exposure approximates that for human exposure. Our findings support earlier suggestions that dogs may serve as environmental sentinels for establishing the geographic prevalence of foci of spotted fever.
Serologie responses of calves to sequential infections with epizootic hemorrhagic disease virus serotypes
Authors: Bowen R. A. 
Published: February 2025

SUMMARY
Six calves were inoculated with 1 of 2 North American serotypes of epizootic hemorrhagic disease virus (ehdv) and then inoculated with the second serotype 16 weeks later. One calf did not develop an immune response to ehdv after primary inoculation and was removed from the study. Viremia after primary inoculation was transient. Although each infected calf developed a high serum neutralizing antibody titer to ehdv, at no time after inoculation with one or both viruses was antibody detected that neutralized any US serotypes of bluetongue virus. After exposure to both serotypes of ehdv, 4 of 5 calves developed antibodies that cross-reacted with group-specific bluetongue virus antigens.
In vitro sensitization and stimulation of bovine lymphocytes with encapsulated or nonencapsulated Smith strain of Staphylococcus aureus
Authors: Ojo-Amaize Emmanuel A. , Guidry Albert J. 
Published: February 2025

SUMMARY
An in vitro immunization procedure was developed, whereby bovine blood and mammary gland lymphocytes were isolated, and their blastogenic responses (measured by [3H]thymidine uptake) to sensitization and subsequent stimulation with selected antigens were determined. Capsular extracts of Staphylococcus aureus, encapsulated S aureus, and nonencapsulated S aureus were used as test antigens. Differences were observed between kinetics of the secondary response to encapsulated and nonencapsulated S aureus. The secondary response to nonencapsulated S aureus peaked in 48 hours, whereas the secondary response to the encapsulated S aureus peaked in 72 hours. The delayed peak response to encapsulated S aureus was observed only when encapsulated S aureus was used for sensitization of lymphocytes, regardless of whether the encapsulated or nonencapsulated strain was used for stimulation. Sensitization of lymphocytes with the nonencapsulated strain and stimulation with the encapsulated strain did not alter the kinetics of the secondary response of cells sensitized with the nonencapsulated strain. Seemingly, T and B cells were responsive to in vitro immunization with S aureus antigens.
Mechanism and isotypes involved in passive immunoglobulin transfer to the newborn alpaca (Lama pacos)
Authors: Garmendia Antonio E. , McGuire Travis C. 
Published: February 2025

SUMMARY
Crias, newborn alpacas (Lama pacos), that were almost agammaglobulinemic at birth had a 70% increase in total serum proteins within 24 hours largely because of absorption of γ globulins from colostrum. Immunoglobulin G was the isotype in highest concentration in colostrum and in serum from 24-hour-old crias. The serum IgG concentration of 10 crias increased linearly (r = 0.97) from a mean of 0.3 mg/ml ( ± 0.1 sd) for serum collected before crias suckled to a maximal mean of 30.1 mg/ml (± 8.1 sd) at 24 hours. The 24-hour concentration decreased by half in 10 days. Immunoglobulin M also was absorbed from colostrum and increased linearly (r = 0.99) from a mean of 0.5 mg/ml (± 0.1 sd) for serum collected before crias suckled to a maximal mean of 4.2 mg/ml (± 2.2 sd) 24 hours after birth. The 24-hour serum concentration of IgM decreased by half in 7 days. Therefore, on a weight basis, 7 times more IgG than IgM was transferred to crias; IgG accounted for > 85% of the passively transferred proteins in serum of 24-hour-old crias.
Absorption of functional antibodies of IgG and IgM isotypes from colostrum of immunized dams by crias also was demonstrated. Immunoglobulin G and IgM antibody titers to chicken RBC increased linearly to maximal geometric mean titers of 1,139 and 843, respectively, 24 hours after birth. The 24-hour IgG and IgM antibody titers decreased by half in 6 and 3.8 days, respectively.
Purified alpaca IgG had a molecular mass of 166 kilodaltons, a predominant γ mobility, and an extinction coefficient of 14.1. Purified alpaca IgM had a molecular mass of 1,000 kilodaltons, a β mobility, and an extinction coefficient of 12.8. In immunodiffusion, alpaca IgG had partial antigenic identity with human IgG, and alpaca IgM had partial antigenic identity with bovine IgM.
Neurophysiology maps of cutaneous innervation of the hind limb of sheep
Authors: Kirk E. J. , Kitchell R. L. , Johnson R. D. 
Published: February 2025

SUMMARY
The area of skin supplied by afferent fibers in a peripheral nerve is called the cutaneous area (ca) of that nerve. The ca of hind limb nerves that were responsive to movement of wool/hairs were mapped neurophysiol-ogically in 25 barbiturate-anesthetized sheep.
The ca of the dorsal cutaneous branches of the caudal lumbar spinal nerves and of the sacral spinal nerves extended over the lateral aspect of the thigh. The ca of the lateral cutaneous femoral nerve was restricted to the stifle region, that of the saphenous nerve did not reach the digits, that of the deep peroneal nerve lay between the 3rd and 4th digits, and that of the lateral plantar nerve was confined to the lateral aspect of the 4th digit. The ca of the superficial peroneal nerve enveloped the dorsal, medial, and lateral aspects of the distal portions of the hind limb. In some sheep, the boundaries of the ca of the superficial peroneal nerve were juxtaposed caudally in such way that the medial plantar nerve did not have an autonomous zone.
Differences in sizes of the ca resulted in corresponding differences in the overlap between adjacent ca and concomitant differences in the sizes of autonomous zones.
Effect of ranitidine on gastric acid secretion in young male horses
Authors: Campbell-Thompson Martha L. , Merritt A. M. 
Published: February 2025

SUMMARY
Gastric cannulas were placed surgically in 5 young male horses. After a 2-week recovery period, horses were studied once a week. Horses were fasted for 24 hours, and gastric fluid output was collected for 5 continuous hours. Volumes were recorded every 15 minutes, and pH and hydrogen ion concentration were determined in an aliquot from each period. In 10 basal experiments, using 5 horses, volume, pH, and hydrogen ion concentration were continuously variable. Mean acid output was 45.1 ± 2.02 μEq/15 min/kg (mean ± sem). In 6 experiments, using 3 horses, 0.5 mg of ranitidine/kg of body weight, given as an rv bolus after a 1-hour basal collection, significantly (P < 0.02) inhibited hourly total acid output for 4 hours, but did not significantly change pH. The cannulation technique was done without complications, and horses tolerated the cannula for several months. Seemingly, the horse has a continuously variable gastric acid secretion, and histamine type-2 receptors have a role in this process.