bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunizing Properties of Westphal Lipopolysaccharide from an Avian Strain of Pasteurella multocida
Authors: Rebers Paul A. , Phillips Marshall , Rimler Richard , Boykins Robert A. , Rhoades Keith R. 
Published: February 2025

SUMMARY
A purified lipopolysaccharide (lps) antigen from an encapsulated strain of Pasteurella multocida was obtained by a modification of the Westphal extraction procedure in which most of the capsular polysaccharides were separated from the lps by partitioning between water and phenol. The lps-enriched fraction was then digested with deoxyribonuclease and ribonuclease, pelleted by ultracentrifugation, and fractionated by equilibrium buoyant density gradient centrifugation in cesium chloride. These procedures removed most of the protein and extraneous polysaccharide components.
The capability of the original extract to induce protection in chickens, mice, and rabbits was determined; evidence of protection was obtained only in chickens. Chicken antiserum obtained by inoculation of the original extract or of the purified lps gave a single line in gel diffusion with homologous lps and with Heddleston's heat-stable antigen of the homologue type; a reaction was not obtained with any of the 15 other serotype antigens. The antiserum obtained by use of the original extract had the same qualitative reactions as did that obtained by use of the purified lps, but the antiserum obtained with the purified lps had stronger serologic reactions and was more effective in the passive protection test. Up to 86% of the chickens given 0.3 ml of the latter antiserum were protected against a challenge exposure which killed 100% of the controls. Pasteurella multocida lps is an important serologic marker in Heddleston's typing system, and antibodies induced against the lps contribute to the protection of chickens.
Effect of Cyclophosphamide Treatment on Clinical and Serologic Response of Rats to Infection with Leptospira interrogans serovar icterohaemorrhagiae
Authors: Thiermann A. B. 
Published: February 2025

SUMMARY
Young albino rats were immunosuppressed with cyclophosphamide and exposed to virulent and low-virulence Leptospira interrogans serovar icterohaemorrhagiae 820K. In rats exposed to virulent and low virulence leptospires, microscopic agglutinating antibody responses occurred later, and longer leptospiremic phase and more massive tissue invasion by the organisms were observed in immunosuppressed rats than in immunocompetent controls. Clinical and pathologic signs of illness were more severe in the immunosuppressed animals than in immunocompetent controls. When exposed to low-virulence leptospires, immunosuppressed rats became infected and developed signs of illness and 2 of 16 died. Immunocompetent rats rapidly developed a humoral response and did not develop any signs of illness, and with 1 exception, organisms were not recovered from any tissues.
Viral Contamination of Bovine Fetal Lung Cultures and Bovine Fetal Serum
Authors: Rossi C. R. , Bridgman C. R. , Kiesel G. K. 
Published: February 2025

SUMMARY
Commercial bovine fetal serum (bfs) and bovine fetal lung (bfl) cells were tested for viruses. The only virus detected in any sample was noncytopathogenic bovine viral diarrhea virus (bvdv). Of 37 bfl cultures initiated, 34 were negative for bvdv, 1 was positive, and 2 were suspicious in that the source of bvdv contamination was not certain. Of 9 lots of irradiated sera tested, 1 (10%) was positive for bvdv; of 21 lots of nonirradiated sera tested, 13 (62%) were positive for bvdv. As judged by intensity of fluorescence in infected cultures, some cell strains were much more susceptible to bvdv than other strains. Heat inactivation of serum at 56 C for 30 minutes was found to be an unreliable method of eliminating bvdv from sera.
Esophageal and Intrapleural Pressures in the Healthy Conscious Pony
Authors: Derksen F. J. , Robinson N. E. 
Published: February 2025

SUMMARY
Pleural and esophageal pressures were compared in 6 standing sedated ponies. Pleural pressure was measured with blunt needles attached to transducers and inserted in the 10th intercostal space level with and 10 and 20 cm above the point of the shoulder. Two balloons (a condom and an esophageal balloon) attached to transducers measured esophageal pressure in the cranial, middle, and caudal portions of the thoracic part of the esophagus. Tidal volume was measured by integrating a flow signal derived from a pneumotachograph attached to an endotracheal tube inserted through a tracheostomy. Frequency responses of all measuring systems were matched. The change in pleural pressure during respiration was greatest in the middle and ventral portions of the thorax, less in the dorsal portion of the thorax and in the middle and caudal portions of the thoracic part of the esophagus, and least in the cranial portion of the thoracic part of the esophagus. The type of esophageal balloon had no effect on the measured pressure change. Regional variations in esophageal or pleural pressure during breathing caused variations in the calculated dynamic compliance. Pleural pressure gradients of 0.33 cm of water/cm of descent and 0.484 cm of water/cm of descent were recorded in the dorsal and ventral halves of the thorax, respectively, and may result in regional variations in lung inflation similar to those observed in persons.
Influence of Plasma A Esterase on Anthelmintic Action of Haloxon in Sheep
Authors: Baker Norman F. , Fisk Robert A. 
Published: February 2025

SUMMARY
Controlled trials were conducted to evaluate the anthelmintic action of haloxon in 2 phenotypes of lambs, 1 having an A esterase in plasma which rapidly hydrolyzes di-(2-chloroethyl)aryl phosphates and the other without this enzyme. A total of 116 lambs, 57 with and 59 without the plasma A esterase, 6 to 9 months old, harboring naturally acquired nematode infections were used in 3 trials. Haloxon was administered orally at 20, 25, and 35 mg/kg of body weight. Nematodes against which haloxon was evaluated in the abomasum were Ostertagia circumcincta and Trichostrongylus axei and in the small intestine were T vitrinas, T colubriformis, Nematodirus spathiger, and N filicollis. The anthelmintic efficiency of haloxon did not differ in the 2 phenotypes of sheep.
Evaluation of an Induced Pasteurella multocida Swine Pneumonia Model
Authors: Bentley O. Eugene , Farrington Daniel O. 
Published: February 2025

SUMMARY
A reproducible swine pneumonia model was developed, utilizing Pasteurella multocida (strain MSU 7) and a rapid endotracheal inoculating technique. The model provided a means of testing various factors, such as therapeutic agents that may influence the course of pulmonary pasteurellosis. In a series of experiments, 81 infected nonmedicated pigs had a morbidity of 96% and a mortality of 22%. Pasteurella multocida was isolated from 62% of the lungs at necropsy; 86% of the lungs had gross lesions characteristic for strain MSU 7 pneumonic pasteurellosis when the pigs were necropsied 7 days after inoculation.
Sedimentation Coefficient of African Swine Fever Virus
Authors: Trautman R. , Pan I. C. , Hess W. R. 
Published: February 2025

SUMMARY AND CONCLUSIONS
The sedimentation coefficient of the infective unit of African swine fever in tissue culture harvest fluids was measured in a preparative ultracentrifuge. The boundary locator method used also permitted making an estimate of heterogeneity. The sedimentation coefficient ranged from 3,000 to 8,000 Svedberg units, representing many classes of infective particles.
Electron microscopy on culture fluids from infected cells showed many kinds of virus-containing units.
Sucrose-CsCl gradient centrifugation was used to concentrate and to purify (partly) African swine fever virus for analytical ultracentrifugation. The optical patterns of the physical particles revealed a range of coefficients from 1,800 to 3,200 Svedberg units in tris-buffered saline solution at 20 C and buoyant densities from 1.19 to 1.24 g/ml in CsCl. The disparity of these values from those obtained by preparative ultracentrifugation indicates a change in the virus structure or a selection of viral populations on purification (or both).
Attempts to Reactivate Bovid Herpesvirus-2 in Experimentally Infected Calves
Authors: Castrucci G. , Frigeri F. , Cilli V. , Tesei B. , Arush A. M. , Pedini B. , Ranucci S. , Rampichini L. 
Published: February 2025

SUMMARY
A study was carried out to determine whether bovid herpesvirus-2 (bhv-2) is able to induce a recurrent infection in experimentally infected calves.
Twelve calves infected with the virus were treated with dexamethasone (dms) beginning 69 days after the infection, ie, several weeks after the animals had recovered from the disease and were negative for bhv-2.
The stress induced by dms treatment failed to reactivate the clinical condition or to induce shedding of bhv-2. However, treatment with dms reactivated a latent infectious bovine rhinotracheitis (ibr) virus infection in all calves previously inoculated with bhv-2, and also in 2 noninoculated controls. The reactivation of ibr virus occurred without any clinical evidence of the disease, but the virus was isolated from nasal and pharyngeal swabbings and from the organs. A proliferative ganglionitis of the trigeminal ganglion was also observed.
Because of the interference by ibr virus, this study did not resolve the question as to whether bhv-2 can induce a recurrent infection.
In Vivo and in Vitro Measurement of Tendon Strain in the Horse
Authors: Lochner Frank K. , Milne Dennis W. , Mills Earl J. , Groom Jack J. 
Published: February 2025

SUMMARY
Strain gauges were applied to the superficial flexor tendon, deep flexor tendon, and suspensory ligament of sound adult horses. Maximum tendon strain occurred during full weight bearing while walking, when the forelimb was perpendicular to the ground surface. There was decrease in tendon strain with increase in hoof angle for the deep digital flexor, but no change in tendon strain for the superficial digital flexor and suspensory ligament with changing hoof angle. At physiologic rates of strain, tendons were able to withstand large loads without yielding. Load strain curves developed in vitro indicated that during walking, the deep digital flexor was calculated to load to 416.8 kg; the superficial flexor tendon to 362.9 kg; and the suspensory ligament to 172.4 kg. This study shows that in the horse, strain in flexor tendons during walking was in excess of 5%, indicating strains within the visco-elastic range.
Incompatibility of R Plasmids Derived from Salmonella and Escherichia coli Strains Isolated Simultaneously from a Bovine Fecal Sample
Authors: Ishiguro Naotaka , Sato Gihei , Ichijo Shigeru , Konishi Tatsuo 
Published: February 2025

SUMMARY
Seven strains of Salmonella typhimurium were isolated from 2 fecal samples of calves, and the strains were resistant to ampicillin, chloramphenicol, kanamycin, nalidixic acid, streptomycin, sulfadimethoxine, and tetracycline. Also, 11 Escherichia coli strains were obtained from 1 of the 2 samples, and these strains possessed the identical drug resistance patterns as did the salmonellae.
The thermosensitive R plasmids conferring sextuple drug resistance and mercury resistance from Salmonella strains were Fi− (no fertility inhibition) and belonged to incompatibility group H1, whereas conjugative 6 R plasmids isolated from 11 E coli strains were Fi+ (fertility inhibition) and belonged to incompatibility group FII. Thermosensitive R plasmids conferring sextuple drug (ampicillin, chloramphenicol, kanamycin, streptomycin, sulfadimethoxine, and tetracycline) have not been reported in Japan. Genetic relationship of R plasmids derived from the multiresistant strains of Salmonella and E coli was discussed on the basis of incompatibility properties of R plasmids.
Glucose-Stimulated Fluid Absorption in the Pig Small Intestine During the Early Stage of Swine Dysentery
Authors: Argenzio R. A. 
Published: February 2025

SUMMARY
Kinetics of glucose-stimulated water absorption and small bowel absorptive function in normal pigs and pigs affected with swine dysentery were examined with a steadystate perfusion technique. Glucose-dependent stimulation of solute and water absorption was shown in normal pigs with a transport constant of 46.9 mM and a maximum change in volume transport capacity of 78.3 ml/h/50 cm of jejunum. The entire small intestine of normal pigs absorbed 10 ml/min of an isotonic fluid when the luminal glucose concentaatinn was 80 mM, whereas the intestine secreted 3 ml/min when glucose was replaced by mannitol. These absorptive and secretory rates in infected pigs were identical to those in control pigs. Electrolyte and acid-base values in arterial blood were unchanged after the rapid administration of 500 ml of a glucose-electrolyte solution into the proximal portion of the small bowel, and the plasma glucose response in control and infected pigs was identical. Seemingly, small bowel absorptive function is normal in pigs with swine dysentery and provides a rational approach to oral, glucose-electrolyte therapy for restoring the extracellular fluid losses that occur with this disease.
Evaluation of a Modified Live-Virus Vaccine for the Prevention of Porcine Parvovirus-Induced Reproductive Disease in Swine
Authors: Paul P. S. , Mengeling W. L. 
Published: February 2025

SUMMARY
Each of 5 gilts was vaccinated im with modified live-virus (mlv) vaccine for porcins parvovirus (ppv), and 5 gilts were used as nonvaccinated controls. Vaccinated gilts developed hemagglutination-inhibiting (hi) antibodies to ppv (titer of 320 to 1,280) by 2 weeks after vaccination. All gilts were bred, and at about 40 days of gestation their immunity was challenged by intranasal and oral administration of a virulent strain of ppv. Gilts were killed at about 84 days of gestation and their Utters were examined. Litters from vaccinated gilts comprised 59 live and 2 dead fetuses. Neither the virus nor antibodies to the virus were detected in any of the fetuses. In contrast, litters from nonvaccinated gilts comprised 25 live and 29 dead fetuses, and ppv was isolated from all dead and 9 live fetuses. Viral antigen was detected by direct immunofluorescence in the lungs of all ppv-infected fetuses, and 7 of the live infected fetuses had hi antibodies.
Modified live virus did not cause transplacental fetal infection in 3 seronegative gilts inoculated at about 40 days of gestation. All 3 gilts had antibodies to ppv (80 to 640) when killed at about 84 days of gestation, and neither hi antibodies nor ppv were detected in any of the 20 live and 1 dead fetuses from these gilts. Modified live virus replicated in the tissues of fetuses of 2 gilts inoculated in utero. Seven of 8 fetuses inoculated with mlv died and were infected.
These results demonstrated the efficacy of mlv vaccine for the prevention of ppv-induced reproductive disease in swine. Although mlv did not cross the placental barrier in pregnant animals, its pathogenicity for porcine fetuses after direct in utero inoculation indicates that its use should be limited to nonpregnant animals.
Response of Muscle Spindle Primary Endings to Static Stretch in Acute and Chronic Spinal Cats
Authors: Bailey Cleta Sue , Lieberman James S. , Kitchell Ralph L. 
Published: February 2025

SUMMARY
To evaluate fusimotor activity, the response of muscle spindle primary endings to static stretch was recorded from group Ia fibers in 8 control cats and in 31 cats at 3, 6, 14, 30, and 60 days after lumbar spinal cord transection. The spindle responses and clinical status of each group were compared with those of the control group. At 3 days after transection, the cats were hypotonic and mildly hyperreflexic. Spindle responses were significantly depressed. By day 6, the cats were mildly hypertonic and significant spindle recovery had occurred, although the responses were still significantly depressed from control levels. Spindle responses, hypertonia, and hyperreflexia continued to increase to day 30. At this time, spindle responses remained significantly depressed, although the cats were markedly hypertonic and hyperreflexic. A significant change in spindle activity or clinical status did not occur from 30 to 60 days after transection.
Antiparasitic Activity of Ivermectin in Critical Tests in Equids
Authors: Lyons E. T. , Drudge J. H. , Tolliver S. C. 
Published: February 2025

SUMMARY
Ten critical tests, using 9 horses and 1 pony, were conducted to evaluate antiparasitic activity of a solution of ivermectin [22, 23-dihydroavermecin B1 (MK-933)] administered in single doses via stomach tube at dosage rates of 50 (3 tests), 100 (3 tests), or 200 (4 tests) μg/kg of body weight.
Removal of 91% to 100% was recorded at all 3 dosage levels (No. of infected animals in parentheses) for 2nd instar (7) and 3rd instar (10) Gaserophilus nasalis, immature (5) and mature (5) Oxyuris equi, Strongylus vulgaris (9), S edentatus (8), and small strongyles (10; only 83% removal in 1 animal at 100 μg/kg). Small strongyles in 2 animals were from benzimdazole-resistant sources and removal was 96% (200 μg/kg) and 100% (100 μ/kg). All mature Parascaris equorum parasites in 2 animals (50 μg/kg) and S equinus in 2 animals (100 μg/kg and 200 μg/kg) were removed.
Removal of G intestinalis 2nd instar (9) was 79% to 100%, 97% to 99%, and 100%, and of 3rd instar (10) was 67% to 88%, 86% to 100%, and > 99% to 100% at dosage rates of 50, 100, or 200 μg/kg, respectively. Probable activity against 4th-stage Habronema spp, 5th-stage Habronema muscae, or both (all 3 dosage levels) and 5th-stage Draschia megastoma (100 μg/kg) was indicated. There was no activity found against tapeworms (Anoplocephala magna and A perfoliata). Transient loosening of feces was obtserved for 1 animal 200 (μg/kg) after treatment but whether it was drug related was unknown.
Endomyocardial Biopsy in the Dog
Authors: Burk Ronald L. , Tilley Lawrence P. , Henderson B. Marshall , James V. C. 
Published: February 2025

SUMMARY
A technique for transvenous endomyocardial biopsy of the right ventricular septum was modified from an existing procedure described in man and was applied in the dog. More than 120 procedures were performed in 36 dogs. One dog died, but lesions noticed at necropsy were not sufficient to establish the specific cause of death. Other fatalities or major complications were not encountered.
Efficacy of Ivermectin Against Dirofilaria immitis Larvae in Dogs 31, 60, and 90 Days After Infection
Authors: Blair Lyndia Slayton , Campbell William C. 
Published: February 2025

SUMMARY
Ivermectin, given as a single oral dose of 0.05 mg/kg, prevented the maturation of Dirofilaria immitis in dogs if given at 31 or 60 days after infection. When treatment was delayed 90 days after infection, maturation of worms occurred in 3 of 5 dogs.
Transmission of Anaplasma marginale Theiler by Dermacentor andersoni Stiles and Dermacentor variabilis (Say)
Authors: Kocan Katherine M. , Hair Jakie A. , Ewing S. A. , Stratton Louie G. 
Published: February 2025

SUMMARY
Cattle were inoculated with a Virginia isolate of Anaplasma marginale Theiler and served as an infective source for laboratory-reared Dermacentor andersoni Stiles and D variabilis (Say) nymphs. Following a molt and subsequent feeding of adult ticks on susceptible cows, transstadial transmission of A marginale occurred from cattle with parasitemias ranging from undetectable (in a carrier cow) to a peak of 27% (in an acutely ill cow). Homogenates of gut tissue from unfed, incubated, and feeding adult ticks that were infected as nymphs were all infective; however, the prepatent period varied according to treatment of ticks after they had molted to the adult stage. Prepatent periods of infections in calves resulting from injection of homogenated tissue from unfed adult ticks was 29 and 34 days longer than the prepatent periods that developed in calves exposed to homogenated tissue from ticks that were feeding or incubated at 37 C for 3 days. Transovarial transmission did not occur when F1 larvae, hatched from eggs produced by female ticks known to be infective, fed on susceptible cattle.
Carriage of Campylobacter jejuni in Healthy and Diarrheic Animals
Authors: Prescott J. F. , Bruin-Mosch C. W. 
Published: February 2025

SUMMARY
Feces from normal and diarrheic animals were cultured for Campylobacter jejuni. A clear difference could not be detected in carriage between normal and diarrheic cattle, horses, pigs, and dogs. Too few diarrheic goats, sheep, and rabbits were sampled for conclusions to be made. Carrriage rates (%) detected in normal animals were as follows: ducks 88.3, chickens 23.8, sheep 13.6, rabbits 11.3, goats 2.7, cattle 2.5, and dogs 0.5. The organism was not isolated from horses and mink. Carriage rates varied within a species between animals from different sources.
Lasalocid for Improved Weight Gains and Control of Coccidia in Lambs
Authors: Foreyt William J. , Parish Steven M. , Foreyt K. M. 
Published: February 2025

SUMMARY
Lasalocid at 25 mg/kg of feed was highly effective in reducing numbers of oocysts in feces of naturally infected ewes and lambs. Treated ewes were fed lasalocid-medicated feed before and after parturition, and the 17 lambs from these ewes also were fed medicated feed until market weight. Lambs fed medicated feed gained 5.26 kg more (P < 0.05) than did the 17 nontreated lambs from nontreated ewes. Naturally infected lambs maintained in semiconfinement acquired coccidia infections between 23 and 64 (mean of 38) days after birth. A coccidiostat given before and during the time coccidia-naive lambs were first exposed to coccidia was necessary to achieve the greatest production response to treatment.
When naturally infected feeder lambs (30.9 kg) maintained in semiconfinement were fed lasalocid-medicated feed at 25 mg/kg of feed or unmedicated feed for 91 days, no significant difference (P > 0.05) in rate or efficiency of gain was detected, even though lasalocid was highly effective against coccidia.
Enzyme-Linked Immunosorbent Assay for Detection of Bluetongue Virus Antibodies
Authors: Hübschle O. J. B. , Lorenz R. J. , Matheka H. D. 
Published: February 2025

SUMMARY
The immune response to bluetongue virus in sheep and cattle was studied by applying a newly developed indirect enzyme-linked immunosorbent assay (elisa). Purified virus obtained by sucrose gradient centrifugation was used at a concentration of 0.01 optical density units to coat individual wells (200 μl) of a microtitration plate. Dilution of antigen was performed in 0.05 M carbonate buffer, pH 9.6, and adsorption lasted for at least 16 hours at 4 C. Coated plates retained their activity for 10 weeks when stored at 4 C. Sera recovered from experimentally infected sheep and cattle were tested together with known negative sera. A good correlation between results was obtained with the modified complement-fixation test and the elisa; however, the elisa proved to be more sensitive. The group specificity of the elisa was proven by testing various type-specific sheep and cattle immune sera. The elisa has potential for the detection of group-specific antibodies to bluetongue virus infection.