bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transplacental infection of porcine fetuses following experimental challenge inoculation with encephalomyocarditis virus
Authors: Christianson W. T. , Kim H. S. , Yoon I. J. , Joo H. S. 
Published: January 2024

Summary
Ten multiparous sows were inoculated between 46 and 50 days of gestation with a fetal swine isolate of encephalomyocarditis virus (emcv) to investigate the ability of the virus to cause transplacental infection and fetal death. Four sows (group 1) were inoculated im with emcv MN-25 that had been passaged 4 times on baby hamster kidney-21 line cell monolayers. Two sows were euthanatized at postinoculation (pi) day 23, and the other 2 sows at pi day 44. An additional 6 sows (group 2) were inoculated IM with the same virus that had been passaged 5 additional times in pigs. Two sows were euthanatized at 14 days, and the remaining 4 sows at PI day 28. Clinical signs were not observed in any of the sows, whereas all sows seroconverted to emcv. In group 1, only 2 of 50 fetuses were mummified. Virus was not recovered, although emcv antibodies were detected in the 2 mummified fetuses. In group 2, the 2 sows that were euthanatized at PI day 14 had 26 normal fetuses and there was no evidence of fetal infection. However, in the 4 sows euthanatized at Pi day 28, 20 of 48 fetuses were mummified, hemorrhagic, or edematous. Encephalomyocarditis virus was recovered from 21 of 48 fetuses. Transplacental infection and fetal deaths in pregnant sows was achieved following infection with emcv passaged in pigs.
Evaluation of colostral IgGl absorption in newborn calves after treatment with alkalinizing agents
Authors: Ayers M. Wayne , Besser Thomas E. 
Published: January 2024

Summary
The effects of alkalinizing agents, administered prior to feeding colostrum, on blood-gas and acid-base values and on absorption of IgGl were determined in 40 newborn Holstein calves. Two treatments, sodium bicarbonate (3 mEq/kg of body weight, IV) and doxapram HCl (2 mg/kg, IV), were evaluated, using a randomized complete-block experimental design. These treatments resulted in significant (P< 0.01) alteration of blood-gas and acid-base values, generally in the direction of normal values for adult cattle. Significant least squares mean effects were detected for sodium bicarbonate treatment on blood pH ( + 0.04 units, P < 0.01), Pco2( + 4.1 mm of Hg, P <0.01), and HCO3 concentration ( + 4.4 mEq/L, P < 0.01). Significant least squares mean effects were detected for doxapram HC1 treatment on blood pH ( + 0.06 pH units, P <0.01) and Pco2(–5.2 mm of Hg, P <0.01). Absorption of colostral IgGl was not affected by the treatments given or by the altered blood-gas and/or acid-base status.
Prevalence of bovine group A rotavirus shedding among dairy calves in Ohio
Authors: Lucchelli A. , Lance S. E. , Bartlett P. B. , Miller G. Y. , Saif L. J. 
Published: January 2024

Summary
Fecal samples were collected from 450 neonatal calves ranging from 1 to 30 days old, between May, 1988 and May, 1989 to estimate the prevalence of bovine group A rotavirus in a stratified random sample of Ohio daily herds. Calves were from 47 dairy herds chosen to be representative of Ohio herds. Bovine group A rotavirus was detected in fecal samples by a cell culture immunofluorescence test (ccif) and elisa. Of 450 samples tested, 46 (10%) were positive by ccif and 67 (15%) were positive by elisa. The agreement beyond chance between the 2 assays was good (kappa = 0.65). The overall prevalence rate of rotavirus shedding was 16.4% (74/450). Forty-three percent (29/67) of the samples positive by elisa were subgroup 1, none were subgroup 2, and the remaining 57% (38/67) could not be assigned to either subgroups 1 or 2. Thirty herds (62.5%) had at least 1 group A rotavirus-positive calf (mean number of samples per positive herd = 12.4), and 17 herds (37.5%) had no rotavirus-positive calves (mean number of samples per negative herd = 6.0). A live oral rotacoronavirus vaccine was used in neonatal calves of only 1 herd and 3 of 17 (17.6%) calves from this herd were positive for group A rotavirus. The percentage of the rotavirus-positive fecal samples from all calves (n = 450) when stratified by fecal consistency was as follows: 28.3% (13/46) had liquid feces; 25.6% (10/39) had semiliquid feces; 23.4% (22/94) had pasty feces; and 10.7% (29/271) had firm feces. Of the rotavirus-positive calves (n = 74), 17.6% (13/74) had liquid feces; 13.5% (10/74) had semiliquid feces; 29.7% (22/74) had pasty feces; and 39.2% (29/74) had firm feces. The average age of calves shedding rotavirus was 14 days (range, 1 to 30 days). Double-stranded (ds) rna extracted from 36 samples positive by 1 or both tests was examined by polyacrylamide gel electrophoresis. All samples positive by this technique (30/36) had long dsrna migration patterns, typical of group A rotaviruses, including samples from calves in the herd in which the oral vaccine was used. Moreover, the electrophoretic migration pattern of group A rotavirus dsrna in these vaccinated calves differed from that of the rotavirus vaccine strain, suggesting the rotavirus strain circulating in this herd was not the vaccine strain. All samples negative by ccif or elisa that had volumes > 5 ml (n = 323) were also subjected to dsrna extraction and polyacrylamide gel electrophoresis for detection of additional group A or nongroup A rotaviruses; none of them were positive by this technique.
Ultrasonographic appearance of the ovaries of dogs during the follicular and luteal phases of the estrous cycle
Authors: Wallace Shellie S. , Mahaffey Mary B. , Miller Doris M. , Thompson Fred N. , Chakraborty Prabir K. 
Published: January 2024

Summary
Ultrasonography of the ovaries of 10 bitches was performed daily, using a 7.5-Mhz transducer with a built-in stand-off pad, from the onset of proestrus until the onset of metestrus. Ovarian size, shape, location, echogenicity, follicular development, and apparent ovulation were monitored. Blood samples were collected twice daily for luteinizing hormone determination and daily for progesterone determination. Vaginal smears were made daily for cytologic evaluation. Ultrasonograms were evaluated independent of hormonal and cytologic data, and the day of ovulation was noted. Initially, the ovaries were uniform and had an echogenicity that was equal to or slightly greater than that of the renal cortex. Follicles appeared as focal hypoechoic to anechoic rounded structures. Ovaries were easier to identify as follicular development progressed. Ovarian size increased with time. Apparent ovulation was characterized by a decrease in number of follicles seen from 1 day to the next, but 1 or more follicles remained in at least 1 ovary of 7 of 10 bitches. The ovaries had an oval shape that became rounded after ovulation. At some time after ovulation, all bitches had cystic (anechoic) structures indistinguishable from follicles. These structures increased in echogenicity and decreased in size with time and may have been follicles that did not ovulate, corpora hemorrhagica, fluid-filled corpora lutea, or cyctic luteinized follicles. Time of ovulation determined by ultrasonography paralleled that predicted on the basis of hormonal data in 9 of 10 bitches and with cytologic findings in all bitches.
Isoelectric focusing of soluble proteins from Fasciola hepatica L, 1758 and Fascioloides magna B, 1875
Authors: Lee C. G. , Zimmerman G. L. , Mulrooney D. M. 
Published: January 2024

Summary
Isoelectric focusing was performed on the soluble proteins of whole-body and excretory-secretory products (esp) of Fasciola hepatica and Fascioloides magna. Adult F hepatica flukes were recovered from experimentally infected sheep and esp obtained from the flukes; portions of liver were cut and frozen at - 70 C. Fascioloides magna adults were collected from naturally infected white-tailed deer and esp obtained; portions of liver were collected from noninfected white-tailed deer.
Adult flukes and their host tissues were homogenized and centrifuged; protein concentrations with their esp were determined and adjusted to < 2.50 mg/ml. Seven esp samples from F hepatica and 1 from Fascioloides magna were subjected to isoelectric focusing with the 2 species of fluke and their respective host liver homogenates. After separation, gels were stained with silver and scanned on a laser densitometer.
Protein banding patterns of the 2 species of flukes were dissimilar. In the pH range of 3.5 to 9.6, the body protein had approximately 30 peaks and esp about 23 peaks in both species. Overall banding patterns of the body protein and esp of both species were distinct from those of respective host tissues. Of the peaks reported as dominant, 3 of the body protein and 2 of esp were shared between the 2 species. Fascioloides magna had more dominant peaks than F hepatica. This technique of soluble protein isoelectric focusing is simple and reproducible, and the 2 fluke species can easily be differentiated by this technique, as well as by morphologic characteristics.
Prevalence of Haemophilus parasuis serovars among isolates from swine
Authors: Rapp-Gabrielson Vicki J. , Gabrielson David A. 
Published: January 2024

Summary
Two hundred sixty Haemophilus spp isolates that had been obtained from the respiratory tract and other sites of swine were acquired from diagnostic laboratories, primarily in the United States and Canada. The majority of isolates (243/260) were biochemically characterized as H parasuis; however, a few isolates of taxa distinct from H parasuis (taxa "minor group," D, E, and F) were identified. Fourteen H parasuis serovars were identified, and of those previously described, the most prevalent were 5 (24.3% of isolates), 4 (16.1%), 2 (8.2%), and 7 (3.7%). Three new serovars that were also prevalent included ND4 (11.1%), ND3 (8.6%), and ND5 (6.6%). Serovars 1, 3, 6, C, D, and new serovars ND1 and ND2 were infrequently identified, and 15.2% of isolates were nontypeable. It was not uncommon to isolate multiple serovars from swine of the same herd or related herds. Distribution of serovars among isolates from the United States and Canada was generally similar; however, a higher prevalence of serovar 5 and a lower prevalence of serovars 2, ND3, and ND5 were evident in isolates from Canada. Comparison of isolates obtained from the respiratory tract of swine without polyserositis with those obtained from swine with polyserositis revealed an increased frequency of serovars 4 and 5, and a decreased frequency of serovar 2, among isolates from swine with polyserositis. However, all prevalent serovars were isolated from swine with polyserositis, and data were not indicative of an association between serovar, site of isolation, or pathogenic potential.
Pharmacokinetics of phenobarbital in horses after single and repeated oral administration of the drug
Authors: Knox D. A. , Ravis W. R. , Pedersoli W. M. , Spano J. S. , Nostrandt A. C. , Krista L. M. , Schumacher J. 
Published: January 2024

Summary
Six healthy mature horses were orally administered a single dose of phenobarbital (26 mg/kg of body weight), then multiple doses (13 mg/kg) orally for 42 consecutive days. Seventeen venous blood samples were collected from each horse after the single dose study and again after the last dose on day 42. Plasma phenobarbital concentration was determined by use of a fluorescence assay validated for horses. Additional blood samples (n = 11) were collected on days 8 and 25 to determine peak and trough concentrations, as well as total body clearance. Phenobarbital disposition followed a one-compartment model. Mean kinetic variables after single and repeated orally administered doses (42 days) were: elimination half-life = 24.2 ± 4.7 and 11.2 ± 2.3 hours, volume of distribution = 0.960 ± 0.060 and 0.914 ± 0.119 L/kg, and clearance = 28.2 ± 5.1 and 57.3 ± 9.6 ml/h/kg, respectively. Results indicated that significant (P < 0.05) difference in half-life and oral clearance existed between single and repeated dosing. The significant decrease in half-life after repeated dosing with phenobarbital may be indicative of enzyme induction. Significant difference was not observed between baseline serum enzyme concentration and concentration measured on day 42, except for γ-glutamyltransferase activity, which was significantly increased on day 42 in 3 of the 6 horses. On the basis of increases in oral clearance observed over 42 days, dose adjustments may be required. By days 25 to 42, pharmacokinetic values indicated that dosages of phenobarbital between 25 and 27 mg/kg administered orally every 24 hours may be needed to maintain steady state plasma concentration of phenobarbital at 20 μg/ml of plasma in mature horses.
Influence of furosemide on hemodynamic responses during exercise in horses
Authors: Olsen S. C. , Coyne C. P. , Lowe B. S. , Pelletier N. , Raub E. M. , Erickson H. H. 
Published: January 2024

Summary
Four hours prior to exercise on a high-speed treadmill, 4 dosages of furosemide (0.25, 0.50, 1.0, and 2.0 mg/kg of body weight) and a control treatment (10 ml of 0.9% NaCl) were administered iv to 6 horses. Carotid arterial pressure (cap), pulmonary arterial pressure (pap), and heart rate were not different in resting horses before and 4 hours after furosemide administration. Furosemide at dosage of 2 mg/kg reduced resting right atrial pressure (rap) 4 hours after furosemide injection. During exercise, increases in treadmill speed were associated with increases in rap, cap, pap, and heart rate. Furosemide (0.25 to 2 mg/kg), administered 4 hours before exercise, reduced rap and pap during exercise in dose-dependent manner, but did not influence heart rate. Mean cap was reduced by the 2-mg/kg furosemide dosage during exercise at 9 and 11 m/s, but not at 13 m/s. During recovery, only rap was decreased by furosemide administration. Plasma lactate concentration was not significantly influenced by furosemide administration. Furosemide did not influence pcv or hemoglobin concentration at rest prior to exercise, but did increase both variables in dose-dependent manner during exercise and recovery. However, the magnitude of the changes in pcv and hemoglobin concentration were small in comparison with changes in rap and pap, and indicate that furosemide has other properties in addition to its diuretic activities. Furosemide may mediate some of its cardiopulmonary effects by vasodilatory activities that directly lower pulmonary arterial pressure, but also increase venous capacitance, thereby reducing venous return to the atria and cardiac filling.
Efficacy of ivermectin delivered from a sustained-release bolus against inhibited early fourth-stage larvae of Ostertagia ostertagi and other nematodes in cattle
Authors: Williams J. C. , Plue R. E. 
Published: January 2024

Summary
The anthelmintic efficacy of ivermectin (ivm) delivered from a sustained-release (sr) bolus was evaluated against natural infections with gastrointestinal tract nematodes in 12 crossbred beef heifers in spring. The 12 calves were randomly allotted to 2 groups of 6 calves each. Group-1 calves were treated with an sr bolus designed to deliver 8 mg of ivermectin/d. Group-2 calves were nontreated controls. Cattle groups were kept in separate concrete-floored pens (grass hay nutrition) and slaughter was performed at 35 days after treatment. Fecal egg counts for group-1 calves remained zero after treatment, except for detection of < 1 egg/g of feces in 1 calf at the time of slaughter; counts in nontreated calves increased. Mean and range of Ostertagia ostertagi inhibited larvae in nontreated calves were 27,093 and 10,622 to 56,368, respectively. Efficacy of the ivm sr bolus was 100% against O ostertagi developing fourth-stage larvae (L4) and inhibited early L4, Haemonchus placei adults, Cooperia punctata and C spatulata adult males, Cooperia spp adult females, Cooperia spp L4, Trichostrongylus colubriformis adults, Bunostomum phlebotomum adults, and Oesophagostomum radiatum adults. Efficacy for O ostertagi and T axei adults was 99.9%. Numbers of nontreated calves infected with C pectinata adult males and Oes radiatum L4 were too low to evaluate efficacy. Calves treated with the ivm bolus gained 10.2 kg, whereas nontreated calves lost 1.8 kg. Abomasal lesions were clearly greater in nontreated calves on the basis of index comparisons of abomasal weight and total live weight and gross pathologic features.
Inhibition of equine mononuclear cell proliferation and leukotriene B4 synthesis by a specific 5-lipoxygenase inhibitor, A-63162
Authors: Olsen S. C. , Atluru D. , Atluru S. , McVey D. S. , Erickson H. H. 
Published: January 2024

Summary
The lipoxygenase metabolites of arachidonic acid have an important role in lymphocyte activation. We used a specific 5-lipoxygenase inhibitor, A-63162, to examine the role of 5-lipoxygenase (5-lo) in equine blood mononuclear cell (bmc) proliferation and leukotriene B4 (ltb4) synthesis after stimulation with mitogen (phytohemagglutinin, pha) or calcium ionophore (A23187). The A-63162 inhibited pha-induced equine bmc proliferation and, at the same concentration, also inhibited A23187-induced ltb4 synthesis. The presence of exogenous interleukin 2 (il-2) or the cyclooxygenase inhibitor indomethacin, failed to reverse the immunosuppression caused by A-63162. Further, we found that A-63162, at the concentration that inhibited bmc proliferation and ltb4 synthesis, had no effect on bmc viability. The addition of the specific protein kinase C inhibitor, H-7, did not inhibit A23187-induced ltb4 synthesis. Results indicate that 5-lipoxygenase metabolites may have an important role in equine lymphocyte activation and that protein kinase C has no role in regulating ltb4 production after A23187 stimulation.
Cardiopulmonary responses to experimentally induced gastric dilatation in isoflurane-anesthetized dogs
Authors: Hodgson D. S. , Dunlop C. I. , Chapman P. L. , Grandy J. L. 
Published: January 2024

Summary
Gastric dilatation was experimentally induced in 6 anesthetized dogs maintained with constant-dose isoflurane in oxygen. An intragastric balloon was used to distend the stomach with a constant 30 mm of Hg pressure for 3.5 hours. The was maintained between 35 and 45 mm of Hg, using intermittent positive-pressure ventilation. Cardiopulmonary measurements prior to stomach distension (baseline) were compared with measurements taken during 0.1, 0.5, 1.0, 1.5, 2.5, and 3.5 hours of stomach distension by analyzing the change from baseline in a randomized-block analysis with each dog as a block. After distending the stomach, cardiac index increased (P < 0.01) from 1.5 to 3.5 hours. Stroke volume did not change, thus the increase in the cardiac index was attributable to an increase in heart rate. During inflation, increases were observed in systemic arterial, pulmonary arterial, and right atrial pressure. Respiratory frequency was unchanged; however, to maintain constant, it was necessary to progressively increase peak airway pressure. Although tended to decrease during gastric dilation, the dogs were never hypoxemic. These results indicate that when our methods are used to maintain a constant anesthetic dose of isoflurane in oxygen, an observed increase in cardiovascular performance is expected. This differs from other studies in anesthetized dogs that have shown reduction in cardiovascular performance following gastric dilatation.
Plasma renin activity and aldosterone and vasopressin concentrations during incremental treadmill exercise in horses
Authors: McKeever Kenneth H. , Hinchcliff Kenneth W. , Schmall L. Michael , Reed Stephen M. , Lamb David R. , Muir William W. 
Published: January 2024

Summary
Six untrained mares were subjected to incremental treadmill exercise to examine exercise-induced changes in plasma renin activity (pra) and plasma aldosterone (aldo) and plasma arginine vasopressin (avp) concentrations. Plasma renin activity, aldo and avp concentrations, and heart rate (hr) were measured at each step of an incremental maximal exercise test. Mares ran up a 6° slope on a treadmill set at an initial speed of 4 m/s. Speed was increased 1 m/s each minute until hr reached a plateau. Plasma obtained was stored at − 80 C and later was thawed, extracted, and assayed for pra and aldo and avp values by use of radioimmunoassay. Exercise caused significant increase in hr from 40 ± 2 beats/min (mean ± sem) at rest to 206 ± 4 beats/min (hrmax) at speed of 9 m/s. Plasma renin activity increased from 1.9 ± 1.0 ng/ml/h at rest to a peak of 5.2 ± 1.0 ng/ml/h at 9 m/s, paralleling changes in hr. Up to treadmill speed of 9 m/s, strong linear correlations were obtained between exercise intensity (and duration) and hr (r = 0.87, P < 0.05) and pra (r = 0.93, P < 0.05). Heart rate and pra reached a plateau and did not increase when speed was increased from 9 to 10 m/s. Plasma aldo concentration increased from 48 ± 16 pg/ml at rest to 191 ± 72 pg/ml at speed of 10 m/s. Linear relation was found between exercise intensity (and duration) and aldo concentration (r = 0.97, P < 0.05). Plasma avp concentration increased from 4.0 ± 3.0 pg/ml at rest to 95 ± 5.0 pg/ml at speed of 10 m/s. The relation between avp concentration and exercise intensity (and duration) appeared to be curvilinear, and was described by an exponential function (r = 0.92, P < 0.05). These data indicate that pra and aldo and avp concentrations increase in horses during progressive treadmill exercise.
Effect of bilateral stimulation on spinal evoked potentials in dogs
Authors: Poncelet L. , Delauche A. , Vinals C. , Balligand M. 
Published: January 2024

Summary
We compared the effects of bilateral vs unilateral tibial nerve stimulation of percutaneously recorded spinal evoked potentials (sep) in the lumbar and caudal thoracic area in dogs. The overall amplitude of the sep is increased by this means. Use of this method could improve legibility of the recordings. Amplitudes of root and interneuronal components of the sep are doubled as are cranially transmitted depolarizations. However, the amplitude of the sep component arising from the primary afferents’ depolarization was less than doubled. Latencies of the components were unaffected by bilateral stimulation. Careful observation of the latencies disclosed a 0.9-ms delay in transmission of the fastest component in the midlumbar area. This delay was consistant with results of previous cordotomy experiments, and could influence precision of conduction velocity measurement.
Characterization of a Salmonella choleraesuis isolate after repeated neutrophil exposure
Authors: Roof Michael B. , Kramer Theodore T. , Roth James A. , Minion F. Chris 
Published: January 2024

Summary
Salmonella choleraesuis strain 38 (glycerol-positive fermentation) was repeatedly exposed to porcine neutrophils in an attempt to mimic in vivo conditions of the host immune system. After phagocytosis, viable intracellular S choleraesuis were isolated and the process was repeated at least 5 times. A fifth-passage strain-38 neutrophil-adapted clone, 38PMNa-5X, was isolated, and was compared with the parent wild-type strain 38 for changes. Strain 38PMNa-5X had increased resistance to killing by hydrogen peroxide and phagocyte killing by porcine neutrophils, as measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction. Strain 38PMNa-5X was less invasive than the parent strain on Vero cell monolayers, and had been cured of a 50-kb plasmid. The 50-kb plasmid was marked with bacteriophage mini-Mu (kanamycin resistant) and was reinserted into strain 38PMNa-5X. Strain 38PMNa-5X was avirulent in mice, but the isolates with reinserted plasmids had intermediate resistance to neutrophil and hydrogen peroxide killing and had restored invasiveness and mouse virulence. Differences in complement sensitivity and enzymatic activity were not observed between the strains.