bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of magnesium-induced urinary disease in the cat and comparison with feline urologic syndrome
Authors: Finco Delmar R. , Barsanti Jeanne A. , Crowell Wayne A. 
Published: February 2025

SUMMARY
Aggregates of struvite crystals caused urethral obstruction in a high percentage of cats fed moist and dry diets supplemented with Mg oxide. Some of the diets were associated with cystolith formation as well. The percentage of Mg in the experimental diets was a misleading indicator of Mg intake because of differences between moist and dry diets in their caloric density. Magnesium homeostasis was maintained in cats ingesting large quantities of Mg. Tissue (kidney, muscle, and rib) concentrations of Mg were the same in cats fed high Mg and control diets. Plasma Mg concentration was increased only in cats ingesting the largest amount of Mg. Magnesium homeostasis was maintained by a marked increase in urine Mg excretion. However, urine Mg concentration was not directly related to Mg intake, apparently because of differences between diets in intestinal absorption of Mg.
Urethral obstruction of experimental cats was not associated with a transient increase in Mg intake, nor did obstructing cats have higher urine Mg concentrations than did nonobstructing cats fed the same diet. This observation indicates that factor(s) other than urine Mg concentration are important in urethral obstruction.
Cats with urethral obstruction due to naturally occurring disease, feline urological syndrome (fus), had markedly lower urine Mg concentrations than cats fed high Mg diets. This finding refutes the theory that cats develop fus because of primary Mg hyperabsorptive phenomena or because of a primary urinary leak of Mg. It also indicates that factors other than urine Mg concentration are involved in the genesis of naturally occurring urethral obstruction. Another difference between the natural and the induced disease was related to the character of the urinary precipitates. Experimental diets higher in Mg concentration caused urolith formation, which is uncommon with fus. Lower Mg diets caused obstruction with aggregates of crystals, but mucus was not observed. However, in the experimental disease induced in the present study, urinary precipitates were predominantly or exclusively struvite, as has been reported in the natural disease.
Many similarities were seen between the diet-induced disease and fus, but factors in addition to Mg intake are involved in the natural disease. The importance of Mg, compared with the undefined factors, remains to be established.
Adhesion of Corynebacterium pilosum by pili to epithelial cells of bovine vulva
Authors: Hayashi A. , Yanagawa R. , Kida H. 
Published: February 2025

SUMMARY
Piliated (P+) and nonpiliated (P-) clones of Corynebacterium pilosum were selected, and their adhesion to the epithelial cells of the bovine vulva and vaginal vestibule was examined. The number of P+ bacteria of C pilosum that adhered to vulval epithelial cells was greater than that of P- bacteria. The adhesion of P+ bacteria, but not P- bacteria, to the epithelial cells was inhibited by the antipilus antiserum; therefore, the adhesion of C pilosum to the epithelial cells of the vulva was primarily dependent on the pili. The number of C pilosum that adhered to the epithelial cells of the bovine vulva and of the vaginal vestibule increased by decreasing the pH.
Effect of the morantel sustained-release bolus, used during one grazing season, on the sensitivity of Ostertagia and Cooperia to morantel tartrate in calves
Authors: Newby T. J. , Yazwinski T. A. , Presson B. L. , Holtzen H. M. , Bischoff M. J. , Featherstone H. E. 
Published: February 2025

SUMMARY
Infective 3rd-stage larvae of Ostertagia and Cooperia, obtained from the feces of nonmedicated and morantel sustained-release bolus (msrb)-treated calves, were orally administered to 2 groups of parasite-free calves. After a 42-day maturation period, a therapeutic dose of morantel tartrate was administered to half of the calves from each group. All calves were necropsied 7 days after treatment. After comparing the nematode counts for the nonmedicated and morantel-treated calves of each group, morantel tartrate was demonstrated to be equally effective against the nonmedicated-derived and msrb-derived nematode populations. The sensitivity of Ostertagia spp and Cooperia spp to morantel tartrate, therefore, was not diminished after use of the msrb for a single grazing season.
Linkage of genes for heat-stable enterotoxin, drug resistance, K99 antigen, and colicin in bovine and porcine strains of enterotoxigenic Escherichia coli
Authors: Harnett N. M. , Gyles C. L. 
Published: February 2025

SUMMARY
Linkages among genes for production of Escherichia coli heat-stable enterotoxin (st), drug resistance, K99 antigen, and colicin were investigated in 2 bovine and 3 porcine strains of enterotoxigenic E coli. In conjugation experiments, all 5 isolates transferred enterotoxigenicity and the ability to produce K99; 4 of the 5 isolates also transferred antibiotic resistance markers, and 3 colicinogenic strains transmitted the ability to produce colicin. In 2 of the 3 colicin-producing strains, the genes for colicin were located along with those for K99 and st on a single plasmid. One of these 2 strains transferred the genes for tetracycline resistance and production of both mouse-active st (STa) and mouse-inactive st, whereas the other transmitted the gene(s) for STa only. Transformation studies with the 3rd strain revealed that the K99 determinant resided on a 22-megadalton (Mdal)R plasmid, and that STa and colicin production were on a 65-Mdal plasmid. Analysis of the plasmids from the transformation experiments revealed that the larger plasmid was conjugative and the smaller plasmid was nonconjugative; stable cointegrate formation occurred between these 2 plasmids. Genetic information coding for the production of STa and K99 were also present on a single plasmid of approximately 80 Mdal in both noncolicinogenic strains.
Anaplasma marginale infections in American bison: Experimental infection and serologic study
Authors: Zaugg J. L. , Kuttler K. L. 
Published: February 2025

SUMMARY
Anaplasma marginale was experimentally transmitted from cattle to bison and back to cattle. Of the 2 splenectomized and 1 intact American bison calves (Bison bison) inoculated with a North Texas A marginale stabilate, 1 splenectomized and 1 intact bison exhibited clinical signs of anaplasmosis. Active parasitemias in these bison were observed along with positive reactions in the rapid card agglutination and complement fixation tests. Blood from the infected bison produced disease in splenectomized bovine calves.
Screening tests for anti-Anaplasma antibodies in 178 blood samples collected from adult bison from the National Bison Range, Montana, revealed 1 rapid card agglutination test-positive sample, and 110 negative, 40 suspect, and 28 positive (15.7%) complement fixation test samples.
Rifampin in the horse: Comparison of intravenous, intramuscular, and oral administrations
Authors: Burrows G. E. , MacAllister C. G. , Beckstrom D. A. , Nick J. T. 
Published: February 2025

SUMMARY
The plasma concentrations and pharmacokinetics of rifampin disposition were determined after a single iv, im, or oral dose of 10 mg/kg of body weight and an oral dose of 25 mg/kg. The overall elimination rate constants per minute were similar for the 10 mg/kg dose (0.0021 ± 0.0004, iv; 0.0017 ± 0.0002, im; and 0.0023 ± 0.0006, orally). The apparent bioavailability was moderate to low for im and oral administrations (59.8% ± 3.2% and 39.5% ± 5.0%, respectively). The rate of absorption was most rapid for oral administration with an absorption half-life of 249.7 ± 71.6 minutes as compared with 403.5 ± 89.7 minutes for im administration. However, the im route produced longer detectable plasma concentrations (50 hours in 2 of the 4 horses). Based on bacterial sensitivity information derived for human and canine isolates, the daily oral administration of 10 mg of rifampin/kg administered in the feed represents a reasonable dose for susceptible gram-positive bacterial pathogens. Higher doses (≥ 25 mg/kg) or iv administration would be required for most gram-negative bacteria. Adverse effects of sufficient severity to limit use of the drug, especially by the oral route of administration, were not encountered under the single-dose experimental conditions used.
Cell-mediated and humoral immune response to Mycoplasma hyopneumoniae in pigs enhanced by dextran sulfate
Authors: Kishima M. , Ross R. F. , Kuniyasu C. 
Published: February 2025

SUMMARY
The effect of dextran sulfate (ds), known to be cytotoxic to macrophages, on the cell-mediated and humoral immune response to nonviable Mycoplasma hyopneumoniae in pigs was investigated. The cell-mediated immune response was determined by means of lymphocyte transformation a test, using uptake of [3H]thymidine in a microculture system and the humoral immune response by means of a microplate complement-fixation test. Peripheral blood lymphocytes from pigs vaccinated with nonviable M hyopneumoniae and ds incorporated substantially more [3H]thymidine than did those from pigs given Mycoplasma or ds alone. The transformation of lymphocytes from M hyopneumoniae-ds vaccinated pigs was enhanced when M hyopneumoniae cells used in the assay system were heated at 60 C for 30 minutes. Similarly prepared M flocculare and M hyorhinis cells also stimulated lymphocytes from M hyopneumoniae-ds vaccinated pigs, but not nearly as great as when M hyopneumoniae cells were used. The humoral antibody response and the cell-mediated immune response to nonviable M hyopneumoniae was markedly enhanced by ds. Pigs were vaccinated with nonviable M hyopneumoniae and/or ds 4 times and challenge exposed intratracheally with viable M hyopneumoniae. Pigs vaccinated with M hyopneumoniae and ds had less severe pneumonia than did nonvaccinated pigs.
Pharmacokinetics of digoxin in sheep: Limitations of the use of biological half-life for interspecies extrapolation
Authors: Dix L. P. , Bai S. A. , Rogers R. A. , Anderson D. L. , Riviere J. E. 
Published: February 2025

SUMMARY
After of single iv digoxin injection of 50 μg/kg of body weight, the serum digoxin concentrations of 4 sheep were fitted to a 2-compartment open model. The mean value for the elimination half-life was 7.15 hours; for area volume of distribution, 13.8 L/kg; and for total body clearance, 1.36 L/kg/hr. A comparison of this study with previous studies in sheep and cattle revealed that serious misconceptions could arise if one chose to rely upon elimination half-life as the sole descriptor of drug disposition. A more informative characterization was determined to be total body clearance and area volume of distribution.
Effect of washing on motility and acrosome morphology of frozen-thawed goat spermatozoa
Authors: Memon Mushtaq A. , Bretzlaff Katherine N. , Ott Randall S. 
Published: February 2025

SUMMARY
Semen from 4 bucks was collected using an artificial vagina and was pooled and divided into 6 aliquots. Three aliquots were washed twice, 15 minutes each time, with Ringer's solution, and the fluid was removed by centrifugation at 950 × g between washes. All 6 aliquots (3 washed and 3 unwashed) were extended with skim milk-glycerol, lactose-egg yolk-glycerol, or tris (hydroxymethyl) aminomethane-citric acid-egg yolk-glycerol and were frozen in straws to −196 C. The semen was then thawed and kept at 37 C for 8 hours. Percentage of sperm motility was estimated, and the percentage of normal acrosomes (na) was determined at 0, 2, 4, 6, and 8 hours after thawing. The experiment was repeated 7 times. The data indicated a significant positive effect (P = 0.0009) of washing on motility, but no effect (P = 0.5347) of extender. There was also a significantly higher percentage of na in washed semen (P < 0.0001). Sperm extended in tris aminomethane-citric acid-egg yolk-glycerol had more na than those extended in lactose-egg yolk-glycerol. Sperm motility and acrosome morphology were depressed also in the presence of seminal plasma for the milk extender, which did not contain egg yolk. Removal of seminal plasma from goat semen was beneficial in preserving the integrity of the spermatozoa after freezing, regardless of the extender used.
Effect of a once-daily suckling program on gastrointestinal parasitism in Angus cows and calves
Authors: Ciordia H. , Stuedemann J. A. , Wilkinson S. R. , McCampbell H. C. , Caudle A. B. , Ernst J. V. 
Published: February 2025

SUMMARY
Over a 2-year period involving a total of 168 Angus cows and their calves, 2 studies were conducted to evaluate the effect of once-daily suckling on cow reproduction, calf growth, and gastrointestinal parasitism. Experiment I compared 2 restricted suckling (rs) groups with 1 normal suckling (ns) group. Each group consisted of 24 cows with their calves (24 cows-calves/group = 24 cows and 24 calves/group). In the rs groups, suckling by the calves was restricted to once a day for 45 days, and then the calves were allowed to suckle normally throughout the remainder of the experiment. In the ns group, the calves suckled normally throughout the experiment. Experiment II compared 2 groups of rs cow-calves (24 cow-calves/group) with 2 groups of 24 ns cow-calves/group.
In experiment I, there were ne differences (P < 0.05) in pregnancy rate or in the average number of nematode eggs/g of feces (epg) between the cows from the 2 treatment groups. The rs calves consistently had higher epg counts than did the ns calves during the 45 days of rs (169 vs 62 epg, P < 0.05) and from the time of their return to pasture until weaning (266 vs 186 epg, P = 0.27). The rs calves also had a higher average coccidia oocyst count during the rs period only. In experiment II, rs cows had a higher pregnancy rate (87.6% vs 66.0%, P < 0.05) and a shorter postpartum interval (83 vs 101 days, P < 0.05) than did ns cows. There was no difference in epg from cows, but the rs calves had higher epg during the rs period (160 vs 115, P = 0.19) and during the pasture period (329 vs 154, P < 0.05) than did the ns calves. In both experiments, ns calves had higher (P < 0.05) adjusted 205-day weights and actual weaning weights than did the rs calves. In experiment I, adjusted 205-day weights for the ns and rs calves were 160.1 and 129.0 kg, respectively. In experiment II, adjusted 205-day weights for ns and rs calves were 148.7 and 121.9 kg, respectively. Under the conditions of the present study, the rs technique improved conception rates in young cows, but resulted in lighter calves with a higher degree of internal parasitism.
Bovine anaplasmosis: Transplacental transmission as it relates to stage of gestation
Authors: Zaugg J. L. 
Published: February 2025

SUMMARY
Six mature, pregnant, anaplasmosis-susceptible and 3 anaplasmosis-carrier beef cows were used in Anaplasma in utero transmission studies. Susceptible cows were randomly allotted into 3 groups of 2 cows each and were inoculated with a Virginia A marginale stabilate. Each group was Anaplasma-exposed once during 1 of the 3 trimesters of pregnancy. Blood samples were obtained from each fetus at various stages of development for evaluation and for subinoculation into splenectomized calves once during gestation. Precolostral blood from neonates was also subinoculated into individual susceptible calves.
Two of the 9 splenectomized calves given fetal blood inoculations developed acute anaplasmosis. The dam of 1 fetus with infective blood was Anaplasma-exposed during the 2nd trimester of pregnancy, and the dam of the second fetus was exposed during her 3rd trimester. Infective fetal blood was obtained during the same trimester of gestation in which the dams were inoculated. Calves given neonatal precolostral blood did not develop anaplasmosis.
Demonstration of vaccine-induced immunity to anaplasmosis without induction of persistent postvaccinal complement-fixing and agglutinating antibodies in yearling steers
Authors: Corrier Donald E. , Johnson Janice S. , Wagner Gerald G. 
Published: February 2025

SUMMARY
The protective effect and anti-Anaplasma complement-fixing and agglutinating antibody responses induced in yearling steers by vaccination with an inactivated Anaplasma marginale vaccine were evaluated by challenge exposure. Eleven 12- to 14-month-old Hereford × Angus steers were randomly allotted into 6 principals and 5 controls. The principals were injected im with 5 ml of vaccine on days 0 and 21. On day 70, the 11 steers were challenge exposed by iv inoculation of A marginale-infected blood.
After a prolonged prepatent period, the vaccinated steers developed a significantly (P < 0.01) lower A marginale parasitemia (8.0%) than did the nonvaccinated controls (26.3%). The persistence of a ≥ 0.5% parasitemia was significantly (P < 0.025) reduced from 34 days in the control to 21 days in the vaccinated group. The percentage reduction in pcv was significantly (P < 0.025) less in the vaccinated group (34%) as compared with the controls (57%). Complement-fixing and agglutinating antibody responses induced by vaccination did not persist for more than 21 days after the 2nd vaccine injection and did not interfere with positive seroconversion resulting from challenge exposure.
Arterial to end-tidal CO2 tension and alveolar dead space in halothane- or isoflurane-anesthetized ponies
Authors: Meyer Robert E. , Short Charles E. 
Published: February 2025

SUMMARY AND CONCLUSIONS
The correlation between end-tidal partial pressure of CO2 (PetCO2) and arterial (PaCO2) was determined for spontaneously breathing ponies under halothane or isoflurane anesthesia. The PetCO2 was useful as a trend indicator of PaCO2 during the first 60 minutes of halothane or isoflurane anesthesia when PaCO2 values were < 60 to 70 mm of Hg. Halothane anesthesia lasting > 90 minutes was associated with PaCO2 values in excess of 60 to 70 mm of Hg, a large arterial- to end-tidal PCO2 difference (PaCO2-PetCO2) and a significant increase in alveolar dead space. These effects were not seen during the same period of isoflurane anesthesia. Arterial blood gas analysis is therefore recommended during halothane anesthesia when the PetCO2 is > 60 to 70 mm of Hg. A decrease in alveolar capillary perfusion relative to alveolar ventilation is the most likely cause for the increase in alveolar dead space during halothane anesthesia. Based on these findings, isoflurane may be superior to halothane for prolonged anesthesia of spontaneously breathing horses.
Direct current stimulation of bone production in the pony: Observations with a diaphyseal osteotomy model
Authors: Collier M. A. , Brighton C. T. , Rendano V. T. , Schryver H. F. , Kallfelz F. A. 
Published: February 2025

SUMMARY
Electrically induced osteogenesis exhibits a dose response curve and can induce bone formation in the absence of trauma and in nonunions. Electrically induced osteogenesis, using direct electric current (dc) in a third metacarpal diaphyseal osteotomy model, in conjunction with internal fixation and postoperative loading, was investigated. Twelve young adult ponies of mixed sex were divided into 2 treatment groups (A and B) of 3 stimulated and 3 controls each and evaluated, using a specifically designed procedure. Stimulated ponies in both groups were given 20 μA of dc via an implanted bone growth stimulator (bgs); group A ponies were stimulated for 60 days and group B ponies for 120 days. Biocompatibility of the bgs was excellent in all ponies. Radiographically, there was more advanced healing with better vascular development in the ponies stimulated for 60 days compared with controls, but no discernible difference was seen at 120 days. Nuclear medical bone imaging revealed a peak uptake at 4 weeks in stimulated groups and the uptake decreased after 8 weeks. Radiopharmaceutical uptake in stimulated ponies was consistently below control uptake throughout the study. Mean specific gravity (sg) of specimens prepared for testing materials properties for group A and B controls were 2.044 ± 0.119 and 1.939 ± 0.065, respectively. The sg for group A and group B stimulated were 1.992 ± 0.049 and 1.876 ± 0.031, respectively. The sg of specimens obtained from metacarpi of age-matched control ponies was 2.194 ± 0.166. The ultimate bending strengths and the flexural moduli of elasticity in 60-day control ponies and stimulated ponies were 57 ± 8.4, 59 ± 23.9 MN/m2 and 89 ± 3.5, 106 ± 6.5 MN/m2 and in 120-day control ponies and stimulated ponies were 13 ± 1.0, 13 ± 3.2 GN/m2 and 13 ± 2.89, 15 ± 0.577 GN/m2, respectively. Sixty-day samples and 120-day samples had ultimate bending strengths (su) of 25% and 50% that of unfractured cortex, respectively. These findings indicate that 20 μA of dc stimulation on a diaphyseal osteotomy model may not stimulate sufficient bone production to affect the mechanical properties of the bone. Therefore, based on our research, clinical use of bgs in fresh fracture management cannot be recommended.
Direct current stimulation of bone production in the horse: Preliminary study with a “gap healing” model
Authors: Collier M. A. , Brighton C. T. , Norrdin R. , Twardock A. R. , Rendano V. T. 
Published: February 2025

SUMMARY
The effect of a 20-μA direct-current implantable bone growth stimulator (bgs) on bone production with a “gap healing” model in the horse was evaluated. The right and left 4th metatarsal bones (Mt-4) were used in 7 adult horses to create the “gap healing” model. A 4-mm section of the Mt-4 bone was resected bilaterally in each horse. The bgs was surgically placed into the 7 left Mt-4 defects. The 7 right Mt-4 defects served as controls. Six horses survived the 16-week experimental period.
Signs of pain, decreased range of limb motion, or lameness was not observed in any animal during the 16 weeks. None of the animals showed complete healing radiographically. Four stimulated sites showed less periosteal reaction and 2 showed greater reaction than the 6 controls. The greatest amount of periosteal reaction or bone resorption was seen around the screws and plates in both groups. Uptakes of 99mTc-MDP in counts/pixel for control sites and stimulated sites were 7.90 and 8.25 in the “gap defect” and 5.19 and 5.06 in the areas adjacent to the gap defect. The ratio of uptake between the gap defect and adjacent area was 1.5 and 1.58 respectively. Biocompatability of the bgs was excellent; however, 1 horse had a broken cathode wire 5 cm from the generator capsule at 6 weeks. All polyethylene cathode sheaths were fluid filled at 16 weeks. The average mineralization rates were 1.57 ± 0.34, 1.71 ± 0.28 mm/day and bone formation activity was 0.0182 ± 0.171, and 0.0168 ± 0.0149 mm2/day for control limbs and stimulated limbs, respectively.
There was no significant difference between groups in any of the histomorphometric values measured. Direct current (20 μA) did not increase bone production in this experiment. Methods to objectively evaluate electrically induced osteogenesis and a “gap defect” model for bgs research on the horse are discussed. The results provide a basis for additional research on electrical stimulation of fractures in the horse and for dose-response studies.