bluuebunny/crossref_metadata_2025_split huggingface dataset:
Warfarin pharmacokinetics in the horse
Authors: Thijssen H. H. W. , van den Bogaard A.E. J. M. , Wetzel J. M. , Maes J. H. J. , Muller A. P. 
Published: February 2025

SUMMARY
The pharmacokinetics of racemic warfarin were studied in 6 adult horses. After iv administration, the plasma concentration of warfarin showed a biphasic decline in time. Analysis of the data, according to 2-compartment kinetics, revealed the following constants: biological half-life was 13.3 hours, apparent volume of distribution was 0.46 L·kg-1, body clearance was 25.3 ml·hour-1·kg-1. Warfarin was bound (91.5%) to plasma proteins. Unchanged warfarin was not detected in the urine. Absorption from the gastrointestinal tract was almost complete.
Concentrations of warfarin in tissue were examined in 4 foals that were given 1 g of warfarin orally 14 hours before they were euthanatized. The concentrations in the kidney were higher than those in plasma (about 2 fold). The hypothrombogenic effect of the acute iv and oral administration of warfarin (0.75 mg/kg of body weight) was noticeable only after 60 hours and lasted for about 30 hours. The effect was weak; the maximum effect was a prolongation of 2.3 s (from 11.5 s to 13.8 s) in thromboplastin time.
Effects on cattle and their calves of tansy ragwort (Senecio jacobaea) fed in early gestation
Authors: Johnson A. Earl , Smart Ross A. 
Published: February 2025

SUMMARY
Tansy ragwort (Senecio jacobaea) fed to pregnant cows on gestation days 15 through 30 in lethal and near-lethal doses did not cause detectable damage to 100-day-old or to full-term fetuses as determined by gross examinations, serum enzyme tests chosen to detect hepatic changes, and by histopathologic examinations. Some cows that appeared normal during gestation expired soon after parturition from typical seneciosis apparently triggered by parturition stress.
Pregnant cows fed 12% smaller tansy ragwort doses on gestation days 30 through 45 had only minimal serum enzyme changes and gave birth to normal calves that had normal serum enzymes up to 64 days after parturition.
Assessment of thyroid functional reserve in the cat by the thyrotropin-stimulation test
Authors: Hoenig Margarethe , Ferguson Duncan C. 
Published: February 2025

SUMMARY
Serum thyroxine (T4) concentrations before and after various iv doses of bovine thyrotropin (tsh) were measured over a 48-hour period in 19 healthy cats. Base-line T4 values, as measured by radioimmunoassay, varied greatly. The peak T4 concentration occurred 6 hours after tsh injection, and there was an increase in post-tsh serum T4 concentration that was linearly related to the logarithm of the dose. Greatest stimulation was seen with the highest dose used (1 U of tsh/kg of body weight), and 6 hours after administration of this dose, the serum T4 concentration range was 4.1 to 8.4 μg/dl. The post-tsh serum T4 concentration and the absolute increase in serum T4 concentration after tsh administration correlated more closely with the tsh dose than did the ratio of post-tsh serum T4 concentration to base-line T4 concentration. Therefore, in cats with normal thyroid-binding protein concentrations, the former indices should represent the most reliable assessment of thyroid functional reserve.
Studies on the pathogenesis of epizootic bovine abortion
Authors: Kimsey P. B. , Kennedy P. C. , Bushnell R. B. , Casaro A. P. , BonDurant R. H. , Oliver M. N. , Kendrick J. W. 
Published: February 2025

SUMMARY
Ornithodoros coriaceus Koch ticks were fed on 37 pregnant cows. The fetuses were obtained from the cows at 23 to 126 days after maternal tick exposure. Characteristic lesions of epizootic bovine abortion were observed only in those fetuses recovered 100 days more or after maternal tick exposure. Fetuses collected between 50 and 100 days showed mild-to-moderate lymphoid and mono-nuclear cell hyperplasia. Reaction in fetuses studied < 50 days after maternal tick exposure were mild. Lesions could not be seen in 2 of the youngest fetuses.
Increases in serum immunoglobulin concentrations were present only in those fetuses examined 80 days or more after their dams had been exposed to ticks. The specificity of the immunoglobulins could not be determined. Sera from 12 fetuses tested failed to fix comple-ment in tests for group-specific chlamydial antibodies.
A wide variety of microbiological cultivation attempts were made to recover the causative agent of epizootic bovine abortion from these fetuses; however, no agent was recovered regularly, and chlamydial organisms were not recovered from any, The significance of 2 recovered agents, apparently viral, is still to be determined. Fetal tissues, both frozen and fresh, collected from fetuses of dams exposed to a feeding of ticks were capable of reproducing the disease after inoculation into pregnant cows or directly into fetuses.
Effect of feeding corn naturally contaminated with aflatoxin on feed efficiency, on physiologic, immunologic, and pathologic changes, and on tissue residues in steers
Authors: Richard J. L. , Pier A. C. , Stubblefield R. D. , Shotwell O. L. , Lyon R. L. , Cutlip R. C. 
Published: February 2025

SUMMARY
Two of 3 groups of Holstein-Friesian steers (groups II and III; n = 5 each) were fed a ration containing corn naturally contaminated with 800 ng of aflatoxin/g. The other group of steers (group I; n = 5) was fed a ration containing noncontaminated corn. The respective rations were fed for 17.5 weeks, except the ration given to group III; the latter's first diet (contaminated with aflatoxin) was changed to a noncontaminated diet after 15 weeks, continuing for the remaining 2.5 weeks. All steers were killed and tissues and fluids were obtained for aflatoxin analysis.
Although aflatoxin B1 and M1 could be detected in blood and urine at several sampling times during the experimental period in groups II and III steers (given the diets containing aflatoxin), there appeared to be no effects on body weight gains and immune phenomena, such as lymphoblastogenesis and antibody production, but there was a waning of the delayed cutaneous hypersensitivity in steers given aflatoxin-contaminated diets. In group III animals (diet was changed to noncontaminated ration at 15 weeks), aflatoxin B1 and M1 disappeared from urine before they were slaughtered. All tissues and fluids, except the rumen contents from these group III steers, were void of detectable aflatoxins B1 and M1 at necropsy. The concentrations of aflatoxin B1 in the rumen content of the latter steers were low. All tissues collected at necropsy from the group II steers fed the aflatoxin diet throughout the 17.5 weeks had detectable aflatoxins B1 or M1 present.
Scanning electron microscopic study of bovine leukemic cells
Authors: Yoshikawa Takashi , Oyamada Takashi , Yoshikawa Hiroyasu , Koyama Hiroyuki , Komoriya Yasunobu 
Published: February 2025

SUMMARY
Scanning electron microscopic observation of (i) leukemic cells in peripheral blood and tumor tissues of 11 cattle with bovine leukosis (adult form, n = 5; calf form, n = 2; and thymic form, n = 4) and (ii) peripheral lymphocytes from 2 cattle with persistent lymphocytosis and from 3 healthy cattle revealed morphologic differences of cell surface structures among various forms of bovine leukosis. These differences indicated an interrelationship of cell surface morphologic features between peripheral lymphocytes and tumor cells. Leukemic cells from cattle with the thymic and calf forms characteristically had a smooth surface. In cells from cattle with the adult form, the majority of abnormal cells in the peripheral blood, possessed numerous elongated microvilli on the cell surface, whereas tumor cells in the tissue were pleomorphic with a long villous, plicated surface or had stubby projections. Most of the peripheral lymphocytes from cattle with persistent lymphocytosis were characterized by a dense arrangement of elongated microvilli on the cell surface.
Influence of intramammary infusion of polymyxin B on the clinicopathologic course of endotoxin-induced mastitis
Authors: Ziv G. , Schultze W. D. 
Published: February 2025

SUMMARY
The influence of giving 1 dose of polymyxin B (l.6 × 106 U/quarter) by the intramammary route to dairy cows to modify the clinicopathologic course of mastitis induced by intramammary infusion of Escherichia coli endotoxin (1 mg/quarter) was examined. Pretreatment with polymyxin B or its simultaneous administration reduced and delayed the typical febrile and leukopenic responses to endotoxin infusion, prevented an increase in plasma lactate dehydrogenase activity and a reduction in plasma zinc concentration, but only marginally influenced the degree of udder inflammation and had no effect on leukocytosis in the milk. Intramammary infusion of polymyxin B at 30 or 60 minutes after endotoxin was infused prevented the increase in plasma lactate dehydrogenase activity and moderated the decrease in plasma zinc concentration, but otherwise failed to alter the clinicopathologic course of endotoxin-induced acute mastitis.
Cell culture-derived Babesia bovis vaccine: Sequential challenge exposure of protective immunity during a 6-month postvaccination period
Authors: Kuttler K. L. , Levy M. G. , Ristic M. 
Published: February 2025

SUMMARY
Cell culture-derived soluble Babesia bovis vaccine admixed with a saponin adjuvant was administered in 2 doses, 3 weeks between doses, to 18 yearling heifers. An additional 9 heifers served as nonvaccinated controls. Comparable groups of these animals were challenge exposed at 131 and 178 days after vaccination, using 1 × 108 B bovis organisms contained in freshly collected blood from a splenectomized calf with ascending parasitemia. Challenge exposure led to no deaths of vaccinated animals, whereas 4 of the control (nonvaccinated) animals died of disease. All clinical and hematologic variables examined indicated that the vaccinated animals had gained immunologic protection in comparison with the control group. An immune recognition as manifested by an anamnestic humoral response to challenge exposure was in evidence in the vaccinated animals.
Acute monensin toxicosis in swine: Effect of graded doses of monensin and protection of swine by pretreatment with selenium-vitamin E
Authors: Van Vleet John F. , Amstutz Harold E. , Weirich Walter E. , Rebar Alan H. , Ferrans Victor J. 
Published: February 2025

SUMMARY
Thirty-two weanling pigs (approx 20 kg each) were used for 2 studies of monensin toxicosis. In the 1st study, 5 groups (designated A through E) of 4 pigs each were given a single oral dose of monensin (10, 20, 30, 40, or 50 mg/kg of body weight) and were observed for 4 days to determine the clinical signs and pathologic alterations. The clinical signs of monensin toxicosis were dose related and included anorexia, diarrhea, lethargy, ataxia, dyspnea, and myoglobinuria; then, death. Clinical signs were not produced by the 10 mg/kg dose of monensin, but mortality resulted within 1 day among pigs given the 50 mg/kg dose. The frequency and severity of monensin-induced myonecrosis were dose-related. Affected pigs had bilaterally symmetrical pale areas of damage in the cranial and caudal thigh muscles, shoulder muscles, and loin muscles. Microscopically, the affected muscles had extensive hyaline necrosis with macrophagic invasion and early regeneration. In a few pigs, there was myocardial necrosis—most often involving the left atrial wall. Myoglobinuria was seen grossly in the pigs given the 50 mg/kg dose that died 1 day after dosing.
In the 2nd study, 6 pigs in 1 group (F) were orally given the 50 mg/kg dose of monensin a day after they were treated with selenium-vitamin E (Se as selenite at dosage of 0.25 mg/kg, and vitamin E as α-tocopherol acetate at dosage of 17 IU/kg); in the other group (G), 6 pigs were treated with placebo (saline solution) before dosing with monensin. Partial protection against monensin toxicosis was provided by Se-E pretreatment as demonstrated by (i) absence of mortality in group F pigs, (ii) smaller increases in serum aspartate aminotransferase and creatine kinase activities in group F pigs than in group G pigs, and (iii) less frequent and less severe clinical signs and lesions.
Bacteriophage typing of Staphylococcus hyicus subsp hyicus isolated from pigs
Authors: Kawano Junichi , Shimizu Akira , Kimura Shige 
Published: February 2025

SUMMARY
Four phages were isolated and used for typing Staphylococcus hyicus subsp hyicus isolated from pigs with or without exudative epidermatitis (ee) in Japan. Sixty-four (85.3%) of the 75 isolates examined were typeable at either routine test dilution (RTD) or 100 × RTD. Two or more kinds of phage patterns were present in the isolates from each pig with ee. All isolates from healthy pigs showed a single-phage pattern.
Fourteen (32.6%) of 43 isolates and 7 (87.5%) of 8 isolates from pigs with ee in Belgium and Czechoslovakia, respectively, were typeable with the 4 phages.
None of 180 isolates of S aureus, 7 (6.4%) of 110 isolates of S intermedius, and 2 (2.3%) of 86 isolates of S epidermidis were typeable.
Antibiotic-associated colitis due to Clostridium difficile in a Kodiak bear
Authors: Orchard John L. , Fekety Robert , Smith James R. 
Published: February 2025

SUMMARY
Clostridium difficile and its toxins usually are present in feces of laboratory animals and persons with antibiotic-associated colitis. We report antibiotic-associated colitis in a captive Kodiak bear (Alaskan brown bear, Ursus arctos) in which C difficile and its cytotoxin were found in feces. This indicates that the colitis associated with C difficile and its toxins can occur in nonlaboratory large animals and that this organism may be the causative agent in certain cases of idiopathic colitis in animals. This case also indicates that nonlaboratory animals may be a source of the organism.
Use of alpha-naphthyl acetate esterase staining to identify T lymphocytes in cattle
Authors: Kajikawa O. , Koyama H. , Yoshikawa T. , Tsubaki S. , Saito H. 
Published: February 2025

SUMMARY
Peripheral blood lymphocytes (pbl), lymph nodes, and/or spleens from clinically normal cattle were examined for cytochemical staining of α-naphthyl acetate esterase (anae). Two types of positive-staining patterns in anae staining resulted. By a combination of anae staining and latex-ingesting test, diffuse anae-positive cells were considered as mononuclear phagocytic cells. Using erythrocyte rosettes, erythrocyte antibody complement rosettes, nylon-wool column technique, surface immunoglobulin (SIg) staining, and the anae staining technique, granular anae-positive lymphocytes were shown to be T lymphocytes.
The frequency of T and B lymphocytes in pbl, spleens, and lymph nodes of clinically normal cattle was measured, using anae staining and SIg staining. In pbl, 47.7% were anae-positive and 26.9% were SIg-positive; in spleens, 22.4% were anae-positive and 53.7% were SIg-positive; and in lymph nodes, 38.5% were anae-positive and 28.3% were SIg-positive. The frequencies of T and B lymphocytes in pbl, spleens, and/or lymph nodes from cattle with enzootic bovine leukosis (ebl) and cattle with persistent lymphocytosis and in tumor cells from cattle with ebl were measured. When compared with those of clinically normal cattle, pbl, spleens, and lymph nodes of cattle with ebl and the pbl of cattle with persistent lymphocytosis contained numerous SIg-positive cells and few anae-positive cells. Tumor cells from cattle with ebl contained 7.3% anae-positive and 78.0% SIg-positive cells.
Bovine genital campylobacteriosis (vibriosis): Vaccination of experimentally infected bulls
Authors: Vasquez L. A. , Ball L. , Bennett B. W. , Rupp G. P. , Ellis R. , Olson J. D. , Huffman M. H. 
Published: February 2025

SUMMARY
The therapeutic efficacy of a Campylobacter fetus subsp venerealis bacterin was determined in experimentally infected bulls. Ten of twelve 5-year-old Angus bulls became infected after being infused intrapreputially with C fetus subsp venerealis. Of the 10 bulls, 6 were vaccinated with 5 ml of C fetus subsp venerealis vaccine on 2 occasions 4 weeks apart.
Preputial washings of the vaccinated bulls were culturally negative by the 8th week after primary vaccination. None of the 18 heifers exposed to the vaccinated bulls became infected. The 4 infected, nonvaccinated bulls remained culturally positive to C fetus (P < 0.002), and each bull infected at least 1 heifer (P < 0.001). Two noninfected, nonvaccinated bulls remained culturally negative and did not infect any heifer.
The 4 infected, nonvaccinated bulls were then vaccinated. Two bulls remained infected 9 weeks after primary vaccination, as determined by the virgin heifer test and cultural examination of preputial washings. Serologic data from 7 sampling periods were different (P < 0.001) for vaccinated vs nonvaccinated bulls at 4 (against K antigen) or 6 (against O antigen) weeks after primary vaccination.
Vaccination was effective in eliminating the infection in most of the infected bulls, but cannot be recommended as the sole measure of control in infected herds.
Protection against Pasteurella pneumotropica during infection with Angiostrongylus cantonensis
Authors: Laubach Harold E. , Kocan A. Alan 
Published: February 2025

SUMMARY
Lung infections of specific-pathogen-free rats were studied to determine cross-immunity between infections with Pasteurella pneumotropica and Angiostrongylus cantonensis. Rats were found to have differences in mortality due to pneumonic infections with P pneumotropica and A cantonensis and to coinfections of P pneumotropica and A cantonensis. Single infections of P pneumotropica were not dosage-dependent in their lethality for specific-pathogen-free rats. The mortality of coinfection with P pneumotropica and A cantonensis was significantly lower than that of a monoinfection with P pneumotropica, demonstrating a cross-protective phenomenon.
Preparation of biologically active components of Mycobacterium bovis, using Triton X-100 or potassium chloride
Authors: Hall Michael R. , Thoen Charles O. 
Published: February 2025

SUMMARY
Methods of producing antigen extracts of Mycobacterium bovis are described. Extraction of M bovis with a chaotropic salt, potassium chloride, or a nonionic detergent, Triton X-100, before autoclaving resulted in the production of soluble M bovis components. These antigens induced delayed-type hypersensitivity responses when injected intradermally in M bovis-sensitized guinea pigs. A comparison of the diameters of the hypersensitivity responses (on the basis of equal protein concentrations in the inoculums) revealed that the potassium chloride extract and the Triton extract of M bovis induced similar responses compared to the response induced with a purified protein derivative of M bovis. These findings indicate alternative methods may be used for the production of biologically active extracts of M bovis.
Ultrastructural myocardial alterations in monensin toxicosis of cattle
Authors: Van Vleet John F. , Ferrans Victor J. 
Published: February 2025

SUMMARY
The myocardial ultrastructural alterations induced in monensin toxicosis were studied in 20 beef calves weighing approximately 180 kg. Six of the calves were given (orally) 25 mg of monensin/kg of body weight, 7 calves were given 40 mg/kg and 5 calves were given 40 mg/kg on days 0 and 7; 2 calves were controls. The calves were euthanatized on days 1, 2, 4, 8, 9, and 11 to determine the sequential development of the cardiac lesions. The initial ultrastructural alterations seen in damaged myocytes from days 1 to 11 in all treated calves were extensive sarcoplasmic vacuolation from mitochondrial swelling and lipid droplet accumulation. By day 4, many degenerated myocytes also contained dense compact myelin figures. From day 4 to day 11, myocardial necrosis had developed in degenerated myocytes of the calves that were given the one or two 40 mg/kg doses of monensin. Necrotic myocytes appeared either as dense fibers with intact sarcomeres or disrupted fibers with hypercontraction bands. Lysing necrotic myocytes had disrupted masses of contractile material, pyknotic nuclei, swollen mitochondria with scattered dense matrical granules, and persisting “tubes” of external lamina. Areas of myocardial necrosis had extensive infiltration of macrophages into the inter-stitium and within the sarcolemmal “tubes” of necrotic myocytes. Macrophages engulfed and lysed fragments of necrotic myocytes. Occasionally, activated fibroblasts were present in the interstitium in areas of myocardial necrosis, but collagen deposition was not observed. Monensin cardiotoxicosis in cattle is characterized by initial myocyte degeneration and delayed onset of myocyte necrosis, and provides a useful model for studies of drug-related myocardial injury.
Respiratory syncytial virus pneumonia in young calves: Clinical and pathologic findings
Authors: Bryson D. G. , McNulty M. S. , Logan E. F. , Cush P. F. 
Published: February 2025

SUMMARY
Nine young calves given respiratory syncytial virus by a combined intranasal and intratracheal route developed a severe respiratory tract disease in which coughing, tachypnea, and hyperpnea were prominent clinical features. Calves were euthanatized on postinoculation (initial) days (pid) 1 to 13.
At necropsy, large areas of consolidation were present in the cranial, middle, accessory, and cranial parts of the caudal lung lobes of calves killed between pid 4 and 13. Histopathologic examination revealed widespread and severe lesions in small bronchi, bronchioli, and alveoli. Multinucleate epithelial syncytia on bronchiolar and alveolar walls, many containing eosinophilic intracytoplasmic inclusion bodies, were present in the lungs of calves killed on pid 4, 5, and 6. Necrosis and epithelial loss, hyperplasia, and metaplasia were also observed in the epithelium of small bronchi and bronchioli. The lumina of these airways were occluded to varying degrees with exudate. Exudate was present within alveoli, and interalveolar septa were markedly thickened. Collapse of the thickened septa produced large areas where alveolar air spaces were totally obliterated.
Repair was evident in the lungs of calves killed at pid 10 and 13 with reepithelialization of damaged bronchiolar mucosa, organization of bronchiolar exudate leading to bronchiolitis obliterans, and peribronchial and peribronchiolar fibrosis.
Inoculation of 3 calves by an intranasal route alone produced a less severe clinical disease with only minimal lesions present at necropsy.
Experimental respiratory syncytial virus pneumonia in young calves: Microbiologic and immunofluorescent findings
Authors: McNulty M. S. , Bryson D. G. , Allan G. M. 
Published: February 2025

SUMMARY
Young calves were inoculated with respiratory syncytial virus (rsv) intranasally or by a combined intranasal and intratracheal route and were killed between postinoculation (initial) days (pid) 1 and 14. Viral antigens were detected by immunofluorescence in nasopharyngeal cells from calves killed between pid 2 and 10. Evidence of infection of the trachea and lungs with rsv was obtained by immunofluorescence and virus isolation in calves inoculated by the combined route, but not in calves inoculated intranasally. Within the lungs, rsv antigens were observed in epithelial cells of bronchioli and alveoli.
The only virus detected in inoculated calves was rsv. With the exception of 1 calf, bacteria or mycoplasmas were not isolated from the lower respiratory tracts of inoculated calves. Antibody to rsv was not detected in calves killed up to pid 5, but 4 of 5 colostrum-deprived calves killed between pid 10 and 13 had antibodies to rsv. Preexisting, maternally derived antibody to rsv did not protect the calves from infection. Seemingly, the clinical signs of pneumonia and pathologic lesions observed in inoculated calves were caused by rsv infection.
A new analgesic drug combination in the horse
Authors: Robertson J. T. , Muir W. W. 
Published: February 2025

SUMMARY
A xylazine and butorphanol drug combination produced minimal and transient hemodynamic effects and no significant respiratory depression when administered to 6 healthy horses. Combining xylazine and butorphanol produced a synergistic analgesic effect and provided good chemical restraint for a standing surgical procedure.