bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of chronic gonadotropin-releasing hormone agonist treatment on serum luteinizing hormone and testosterone concentrations in boars
Authors: Almond Glen W. , Esbenshade Ken L. , Smith Craig A. , Richards R. Gregg
Published: January 2024

Mature boars were subjected to chronic treatment with a gonadotropin-releasing hormone (GnRH) agonist, goserelin (D-Ser[But]6, Azgly-NH210), and serum luteinizing hormone (lh) and testosterone concentrations were measured. Ten sexually mature boars were randomly assigned to treatment (n = 5) or control (n = 5) groups. On day 0, boars were implanted sc (day 0) with 2 GnRH agonist implants (1 mg of GnRH/implant) or sham implants. Blood samples were collected at 12-hour intervals on days – 2 and –1, at 6-hour intervals on days 0 through 4, and at 12-hour intervals on days 5 through 8. In addition, blood samples were collected at 15-minute intervals for 6 hours on days –1, 0, 4, and 8. Serum testosterone and (lh concentrations were determined by radioimmunoassay. Maximal (lh (7 ± 1 ng/ml) and testosterone (26 ± 3 ng/ml) concentrations were observed at 5 and 18 hours, respectively, after GnRH agonist treatment. Subsequently, (lh and testosterone concentrations decreased to pretreatment values (0.3 ± 0.1 ng/ml and 1.8 ± 0.4 ng/ml, respectively) by 24 and 48 hours, respectively, after GnRH agonist implantation. Few differences in the characteristics of pulsatile (lh release were observed between the groups. Testosterone and lh concentrations in samples collected at 6- and 12-hour intervals and pulsatile (lh release did not change after sham treatment of control boars. Whereas previous reports indicated that chronic GnRH administration suppressed serum lh and testosterone concentrations in rams, rats, and dogs, our results indicate that chronic GnRH agonist treatment induced transitory increases, without subsequent suppression, in lh and testosterone concentrations in mature boars.
Development of monoclonal antibody ELISA for simultaneous detection of bovine coronavirus, rotavirus serogroup A, and Escherichia coli K99 antigen in feces of calves
Authors: Thorns Christopher J. , Bell Michael M. , Chasey David , Chesham John , Roeder Peter L.
Published: January 2024

A rapid elisa was developed for simultaneous detection of bovine coronavirus (bcv), rotavirus (rv) serogroup A, and Escherichia coli K99 antigen in feces of calves. A mixture of 3 monoclonal antibodies specific for bcv, rv, or K99 was used successfully to capture the antigens; the same antibodies labeled with peroxidase were used to detect bcv, rv, or K99. The triple elisa was compared with standard reference diagnostic methods by examining feces from experimentally and naturally infected and healthy calves. All the components of the test were highly specific (> 90%) and sensitive (bcv, 77%; K99, 93%; rv, 100%) when used in a format requiring short incubation steps at 20 C and visual recording of results.
Ultrasonographic examination of the liver in sheep
Authors: Braun Ueli , Hausammann Karin
Published: January 2024

The purpose of the study reported here was to get detailed information about the normal size and texture of the liver in sheep by means of ultrasonographic examinations. Structure, location, and shape of the liver, gallbladder, portal vein, and caudal vena cava were examined ultrasonographically in 100 sheep. Furthermore, 10 sheep were scanned 10 times within 2 weeks to determine reproducibility of findings. Examinations were performed on the right side of the abdomen in the seventh through twelfth intercostal spaces. In each intercostal space, the dimensions of the liver, and, if visible, the location and diameter of the caudal vena cava and portal vein were determined. The angle of the liver, and location and size of the gallbladder also were determined. Ultrasonographic measurements of liver size and location in healthy sheep can be used as references for changes in liver size attributable to illness.
Increased elastase activity in nasal mucus associated with nasal colonization by Pasteurella haemolytica in infectious bovine rhinotracheitis virus-infected calves
Authors: Briggs Robert E. , Frank Glynn H.
Published: January 2024

Four healthy calves were inoculated with Pasteurella haemolytica serotype 1 by instillation of a broth culture into the middle nasal meatus of the left nostril. Four weeks later, calves were exposed to infectious bovine rhinotracheitis virus by aerosol into both nostrils. All calves became ill, from approximately day 3 through day 10 after virus exposure, and shed increased amounts of nasal mucus. Two calves were induced to shed P haemolytica by the virus infection, and 2 calves required reinoculation with P haemolytica for nasal passages to become actively colonized.

Elastase activity in nasal mucus increased about 15-fold within 3 days and peaked about 60-fold over baseline by 7 days after virus exposure. Activity of N-acetyl-β-d-glucosaminidase, a measure of cell damage and serum leakage, increased slightly by day 3 and reached plateau on day 5, almost threefold over baseline activity. Protein and carbohydrate content increased at a rate similar to that of N-acetyl-β-d-glucosaminidase activity with about 12-fold and sixfold increases, respectively. None of the variables returned to baseline by 19 days after virus exposure. Increased elastase activity preceded colonization by P haemolytica and decreasing elastase activity preceded decreasing P haemolytica concentration in the nasal secretions. A causal relation between elastase activity and P haemolytica colonization could be mediated by cleavage of epithelial cell surface fibronectin and exposure of receptors.
Modulation of thermal killing of bovine lymphocytes and preimplantation mouse embryos by alanine and taurine
Authors: Malayer Jerry R. , Pollard John W. , Hansen Peter J.
Published: January 2024

Addition of alanine and taurine blocked killing of lymphocytes caused by culture at 45 C. The optimal concentration for thermoprotection was achieved at 12.5 mM for l-alanine and 5 mM for taurine. Both d and l forms of alanine provided thermoprotection. The effect of these agents was not simply to increase osmolarity of the culture medium, because NaCl did not provide thermoprotection at comparable concentrations. Alanine and taurine were each tested at concentration of 50 mM for ability to block heat shock-induced killing and developmental retardation of 8- to 16-cell mouse embryos. Both agents enhanced embryo development after exposure to high temperature, though development remained less than that for embryos not exposed to high temperature. In one experiment, for example, 81% of embryos cultured at 38 C advanced in development during culture vs 0% at 42 C, 15% at 42 C with alanine, and 32% at 42 C with taurine. The beneficial effect of alanine at high temperature may have been partly attributable to effects independent of thermoprotection, because development of embryos cultured at 38 C was also improved by alanine.
Investigation of antibodies to extractable nuclear antigens in dogs
Authors: White Stephen D. , Rosychuk Rod A. W. , Schur Peter H.
Published: January 2024

Determination of antibodies to specific nuclear antigens, termed extractable nuclear antigen (ena), was investigated in healthy dogs and in dogs with autoimmune, inflammatory, and neoplastic diseases. Using a counter-immunoelectrophoresis method, the dogs' sera were tested for antibodies against the nuclear antigens single-stranded dna, Sm, Ro, La, ribonucleoprotein, Scl, and proliferating cell nuclear antigen. Antibodies to the Ro antigen were found in 1 dog with discoid lupus erythematosus, in 1 dog with pemphigus erythematosus, and in 1 dog with facial pyoderma and chronic superficial keratitis. In 15 dogs, antibodies were detected to ena, but the precipitin lines were too weak to identify the specific ena. These antibodies were found in some dogs with systemic lupus erythematosus, discoid lupus erythematosus, pemphigus erythematosus, dermatomyositis, vitiligo, lymphoma; in the dog with facial pyoderma and chronic superficial keratitis; and in 1 healthy dog. The highest percentage of dogs with antibodies to ena in a large series (> 8) of this study was in dogs with systemic lupus erythematosus (4 of 13; 31%).
Morphologic and biochemical study of sternal cartilage autografts for resurfacing induced osteochondral defects in horses
Authors: Vachon Anne M. , McIlwraith C. Wayne , Powers Barbara E. , McFadden Paul R. , Amiel David
Published: January 2024

Using biodegradable pins, sternal cartilage autografts were fixed into osteochondral defects of the distal radial carpal bone in ten 2 to 3-year-old horses. The defects measured 1 cm2 at the surface and were 4 mm deep. Control osteochondral defects of contralateral carpi were not grafted. After confinement for 7 weeks, horses were walked 1 hour daily on a walker for an additional 9 weeks. Horses were euthanatized at 16 weeks. Half of the repair tissue was processed for histologic and histochemical (H&E and safranin-O fast green) examinations. The other half was used for the following biochemical analyses: type-I and type-II collagen contents, total glycosaminoglycan content, and galactosamine-to-glucosamine ratio. On histologic examination, the repair tissue in the grafted defects consisted of hyaline-like cartilage. Repair tissue in the nongrafted defects consisted of fibrocartilaginous tissue, with fibrous tissue in surface layers. On biochemical analysis, repair tissue of grafted defects was composed predominantly of type-II collagen; repair tissue of nongrafted defects was composed of type-I collagen. Total glycosaminoglycan content of repair tissue of grafted defects was similar to that of normal articular cartilage. Total glycosaminoglycan content of nongrafted defects was 62% of that of normal articular cartilage (P < 0.05). Repair tissue of all defects was characterized by galactosamine-to-glucosamine ratio significantly (P < 0.05) higher than that of normal articular cartilage. These results at 16 weeks after grafting indicate that sternal cartilage may potentially constitute a suitable substitute for articular cartilage in large osteochondral defects of horses.
Hematologic values in newborn beef calves
Authors: Adams R. , Garry F. B. , Aldridge B. M. , Holland M. D. , Odde K. G.
Published: January 2024

Hematologic values were determined in 35 beef calves at birth, at 24 and 48 hours, and in 22 of these calves at 3 weeks after birth. Thirty calves did not have clinical signs of disease throughout the 3-week period. Variables that changed significantly over time in these healthy calves included hematocrit, rbc count, hemoglobin concentration, mean cell volume, mean cell hemoglobin concentration, wbc count, neutrophil-to-lymphocyte ratio, and plasma total protein and serum immunoglobulin concentrations.

Of the 35 calves, 5 had clinical signs of disease at 3 weeks. Comparison of hematologic values from these calves with values for healthy calves revealed significant differences at each sample collection time, although disease was not evident at the 3 early sample times. The band neutrophil count and the neutrophil-to-lymphocyte ratio differed between the 2 groups at birth. At 24 hours, the monocyte count was higher in the 5 ill calves. At 48 hours, total leukocyte, mature neutrophil, and monocyte counts, and neutrophil-to-lymphocyte ratio also were higher in the 5 calves. At 3 weeks when clinical signs of disease were detectable in the 5 calves, the total leukocyte, band neutrophil, and mature neutrophil counts, neutrophil-to-lymphocyte ratio, and plasma total protein and fibrinogen concentrations were higher.

When calves were grouped and compared at each sample collection time on the basis of sex (male vs female) and meconium staining at delivery (no staining vs staining), significant differences in hematologic values were not observed between groups. When calves were grouped on the basis of delivery assistance (assistance vs no assistance), hematocrit, rbc count, and hemoglobin concentration were significantly lower in delivery-assisted calves during the first 48 hours of life.
Measurement of serum myoglobin concentrations in horses by immunodiffusion
Authors: Holmgren Nils , Valberg Stephanie
Published: January 2024

Quantitative immunodiffusion in one dimension was performed in 6-mm Duran tubes containing a 1% Nobel agar solution and various dilutions of antisera. A series of dilutions of pure myoglobin in equine sera as well as plasma from horses with rhabdomyolysis were tested. Standard curves were prepared of the migration distance of the formed precipitate from the meniscus of the gel after 3, 6, 12, and 24 hours. The clearest line of precipitate was formed with a 1:20 dilution of antisera in agar. Standard curves were nonlinear and plasma myoglobin could be detected at 2 μg of myoglobin/ml or greater. The test was optimal, with an error of 5.6%, when read at 24 hours at approximately 25 C. Tubes with agar could be stored for 6 months at 4 C without affecting the accuracy of the test. The specificity of myoglobin for skeletal or cardiac muscle, and its rapid clearance from serum after muscle necrosis, make it ideally suited for evaluating acute muscle damage and for testing the susceptibility of horses for rhabdomyolysis following an exercise test.
Isolation and characterization of α1-acid glycoprotein from horses, and its evaluation as an acute-phase reactive protein in horses
Authors: Taira Tomoko , Fujinaga Toru , Tamura Keiji , Izumi Minoru , Itoh Hiroshi , Tsunoda Nobuo , Yamashita Kazuto , Okumura Masahiro , Mizuno Shinya
Published: January 2024

Equine α1-acid glycoprotein (α1ag) was isolated from equine serum by successive ammonium precipitation, anion- and cation-exchange chromatographies, and gel filtration. Purified equine α1ag had a molecular weight of 46,000 ± 1,000, and contained 31.4% carbohydrate. Gel isoelectric focusing revealed an isoelectric point range of 2.8 to 3.7. With immunoelectrophoresis, it was found that α1ag migrated to the α1-globulin region.

Single radial immunodiffusion was used for quantitative measurement of α1ag in equine serum. In clinically normal foals, serum α1ag was undetectable (≤ 20 ng/ml) in ≤ 7-day-old foals, but was detected by 14 days. The α1ag concentration (mean ± sd) increased to reach mean adult values of 99.23 ± 26.90 μg/ml by 1 year of age. The α1ag concentration in pregnant mares decreased at 2 to 3 months before parturition, then gradually increased until 1 day after parturition, when a brief decrease was observed. The concentration increased again at 2 weeks after foaling, then a decrease was observed, after which the α1ag concentration increased again by 2 to 4 months after parturition.

The concentration of serum α1ag quickly rose to peak values 2 to 3 days after castration and jejunojejunostomy in adult horses, returning to baseline values by 14 to 28 days after surgery. The α1ag was concluded to be an acute-phase reactive protein in horses.
Comparison of antibody responses in cattle to outer membrane proteins from Pasteurella haemolytica serotype 1 and from eight untypeable strains
Authors: Simons K. R. , Morton R. J. , Fulton R. W. , Confer A. W.
Published: January 2024

Membrane associated proteins from 8 untypeable Pasteurella haemolytica strains were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and compared with those of P haemolytica serotypes 1 and 2. Cattle antisera obtained from P haemolytica serotype 1 vaccine trials were used in immunoblotting assays to compare the membrane proteins from the 8 untypeable strains with those from P haemolytica serotypes 1 and 2. Densitometry was used to identify bands, and using linear regression analyses, the peak area optical densities (measuring antibody response) were correlated to lesion scores from the vaccinated calves. Significant antibody responses to proteins of 99, 69, 60, 55, 47, 45, 39, 33, 30, 16, and 14.5 kDa were detected for 4 or more of the 8 P haemolytica untypeable strains. Serotypes 1 and 2 of P haemolytica contained a comigrating 30-kDa protein. Antibody responses to proteins of 39, 33, and 32.5 kDa were significant for 3 of the untypeable strains and had significant correlation to lesion scores. Antibody responses to various other proteins were significant for 2 untypeable strains each.
Effects of intra-articular administration of methylprednisolone acetate on normal articular cartilage and on healing of experimentally induced osteochondral defects in horses
Authors: Shoemaker R. Stuart , Bertone Alicia L. , Martin George S. , McIlwraith C. Wayne , Roberts E. D. , Pechman Robert , Kearney Michael T.
Published: January 2024

The effects of intra-articular administration of methylprednisolone acetate (mpa) on the healing of full-thickness osteochondral defects and on normal cartilage were evaluated in 8 horses. In group-1 horses (n = 4), a 1-cm-diameter, full-thickness defect was created bilaterally in the articular cartilage on the dorsal distal surface of the radial carpal bone. Cartilage defects were not created in group-2 horses (n = 4). One middle carpal joint was randomly selected in each horse (groups 1 and 2), and treated with an intra-articular injection of 100 mg of mpa, once a week for 4 treatments. Injections began 1 week after surgery in group-1 horses. The contralateral middle carpal joint received intra-articular injections of an equivalent volume of 0.9% sodium chloride solution (scs), and served as a control. Horses were evaluated for 16 weeks, then were euthanatized, and the middle carpal joints were examined and photographed. Synovial and articular cartilage specimens were obtained for histologic and histochemical evaluation.

Gross morphometric evaluation of the healing defects in group-1 horses revealed that 48.6% of the defect in control joints and 0% of the defect in mpa-treated joints was resurfaced with a smooth, white tissue, histologically confirmed as fibrocartilage. This replacement tissue was a firmly attached fibrocartilage in control joints and a thin fibrous tissue in mpa-treated joints. The articular cartilage in joints treated with mpa had morphologic changes, including chondrocyte cluster formation, loss of palisading architecture, and cellular necrosis in both groups of horses. Histochemical (safranin-0) staining intensity was reduced significantly (P < 0.05) in all layers of articular cartilage in mpa-treated joints in groups 1 and 2. In the replacement tissue, intense safranin-0 staining was found only in the chondrocyte clusters deep in the tissue of control joints, confirming fibrocartilage repair. Intra-articular administration of mpa in this dosing regimen thus induced degenerative changes in normal articular cartilage and resulted in histomorphologic changes in the repair of full-thickness articular osteochondral defects in horses.
Biological properties and genetic analysis of the ompA locus in chlamydiae isolated from swine
Authors: Kaltenboeck Bernhard , Storz Johannes
Published: January 2024

Eight strains of Chlamydia psittaci isolated from swine with pneumonia, pleuritis, pericarditis, and enteritis were characterized through analysis of the major outer membrane protein gene ompA by a two-step polymerase chain reaction, by their interactions with cells in culture, and the morphologic features and ultrastructure of intra-cellular inclusions. Amplified chlamydial ompA dna fragments were differentiated by restriction endonuclease digestion. Chlamydial isolates were separated into 2 types on the basis of ompA restriction fragment length polymorphism. Strains of type L71 had finely granular inclusions, whereas those of type 1710S contained pleomorphic reticulate bodies (rb) in the inclusions, which are characteristic of aberrant chlamydial developmental forms. Chlamydial types L71 and 1710S required centrifuge-assisted inoculation for efficient infection of cell cultures. Cultivation in cell culture medium containing cycloheximide increased the numbers of chlamydial inclusions about 1.5-fold. These strains formed few elementary bodies in yolk sac cells of chicken embryos. Ultrastructurally, unique doublet rb were observed, particularly in strains of the ompA type L71. These doublets consisted of 2 rb, bounded by a cytoplasmic membrane, contained within a common cell wall and an extended periplasmic space. Ultrastructural examination of strains of the ompA type 1710S confirmed the aberrant chlamydial developmental forms, but evidence of viral infection of the rb as a cause of these aberrant forms was not found. The strain S45 isolated from intestinal sites of swine was a trachoma restriction fragment length polymorphism type. With the mouse biotype, it represented the second isolate from animals of Chlamydia trachomatis.
Influence of conditioned media from bovine cotyledon tissue cultures on function of bovine neutrophils
Authors: Hoedemaker Martina , Lund Lisa A. , Weston Patricia G. , Wagner William C.
Published: January 2024

Bovine fetal placental (cotyledon) tissue obtained from pregnant cows on days 255, 265, and 275 of gestation, as well as immediately after parturition (n = 5) was incubated in media for 48 hours, and the incubation media were collected. Neutrophils from 4 ovariectomized nonpregnant cows were incubated for 2 hours with conditioned media from placental tissue cultures or medium (control). Immediately after incubation, the neutrophils were subjected to the following leukocyte function assays: chemotaxis against zymosan-activated serum, chemotaxis against undiluted conditioned media (only neutrophils that were incubated in medium only), random migration, ingestion of 125I-iododeoxyuridine Staphylococcus aureus (125I-IdUR-S aureus), iodination of proteins, cytochrome C reduction, and antibody-independent and -dependent cell-mediated cytotoxicity. Conditioned media from cultured cotyledon tissue was chemoattractant for bovine neutrophils, and increased chemotactic response of neutrophils against zymosan-activated serum by 13%. The following neutrophil functions were decreased: random migration by 25%, iodination of proteins by 44%, cytochrome C reduction by 13%, and antibody-dependent cell-mediated cytotoxicity by 5%. Ingestion of 125I-IdUR-S aureus and antibody-independent cell-mediated cytotoxicity were not influenced by coincubation of neutrophils and conditioned media. Time of gestation did not alter the effects of conditioned media on neutrophil function. It was concluded that chemotactic properties of cotyledon tissue extracts, as has been reported earlier, may be attributable to substances released by fetal placental tissue. Those substances might also locally or systemically influence the oxygen-dependent antimicrobial system of neutrophils, thereby causing an increased susceptibility to bacterial infections in the peripartum period.
Comparison of the nonionic contrast agents, iopromide and iotrolan, for positive-contrast arthrography of the scapulohumeral joint in dogs
Authors: van Bree Henri , Van Rijssen Bernadette , Tshamala M. , Maenhout T.
Published: January 2024

Arthrographic quality and synovial inflammatory response were examined to compare the use of iopromide with that of iotrolan for arthrography of the scapulohumeral joint in 6 dogs. Radiographs obtained 1 and 3 minutes after injection of either nonionic compound were of similar quality, but radiographs obtained 5 minutes after injection of iotrolan were significantly (P < 0.05) better than those obtained after injection of iopromide.

Results of analysis of synovial fluid samples obtained at 1, 3, 7, and 14 days after injection of contrast media were not significantly different between the 2 groups. Histologic examination of synovium and articular cartilage 2 weeks after injection of iopromide or iotrolan revealed minimal inflammatory response for both contrast agents. Injection of iopromide and iotrolan into the scapulohumeral joints of dogs had less effect on synovial fluid than that reported after injection of ionic compounds.
Protein kinase-C activity in phorbol myristate acetate-stimulated neutrophils from newborn and adult cattle
Authors: Doré Monique , Neilsen Nancy R. , Slauson David O.
Published: January 2024

Neutrophils from newborn calves have been shown to be deficient in ability to generate superoxide anion (O2-) after stimulation of the respiratory burst enzyme with the phorbol ester, phorbol 12-myristate 13-acetate (pma). This compound activates the O2--generating enzyme of bovine neutrophils through a pathway involving protein kinase C (pkc). To investigate the biochemical basis underlying this functional difference between neutrophils from newborn and adult cattle, we measured and compared the activity of the enzyme pkc in nonstimulated and pma-stimulated bovine neutrophils. Neutrophils from newborn calves (n = 5) and adult cows (n = 5) were stimulated with various concentrations of pma (0, 10, 100, and 500 ng/ml) for 3 minutes, and pkc activity was assayed in the cytosolic and the membrane fractions. In nonstimulated cells, most pkc activity was detected in the cytosolic fraction of neutrophils from newborn and adult cattle. Activity ofpkc in the cytosol was dependent on the presence of added calcium and phospholipids, whereas membrane-associated pkc in nonstimulated cells did not have such dependence. Significant differences in pkc activity were not observed between newborn and adult cattle in either the cytosolic or the membrane fractions from nonstimulated cells. Stimulation with pma caused redistribution of pkc activity in the cell (translocation) in newborns and adults, consisting of decrease in cytosolic pkc activity and increase in membrane-associated pkc activity. Similar to that in nonstimulated cells, pkc activity in cytosolic fractions from pma-stimulated neutrophils was dependent on the presence of cofactors (calcium and phospholipids), whereas pkc activity in the membrane did not have such requirement. Translocation of pkc from the cytosol to the membrane was expressed as percentage of decrease of activity in the cytosol and increase of activity in the membrane, compared with that in nonstimulated cells. Overall, significant differences were not evident in the ability of neutrophils from newborn and adult cattle to translocate pkc after stimulation with various concentrations of pma. Results indicate that differences in redistribution of pkc activity are not responsible for the difference observed in O2- production between neutrophils from newborn calves and adult cattle after cells are stimulated with pkc agonists.
Effect of diet on results obtained by use of two commercial test kits for detection of occult blood in feces of dogs
Authors: Cook Audrey K. , Gilson Stephen D. , Fischer W. David , Kass Philip H.
Published: January 2024

To evaluate the effect of diet on results obtained by use of 2 commercial test kits for detection of occult blood in feces, 5 dogs were fed 7 diets in randomized sequence. Dry and canned diets with various principal ingredients were evaluated. Each diet was offered twice over a 24-hour period, followed by a 36-hour nonfeeding period. Fecal specimens were collected twice daily, and tests for occult blood were performed within 12 hours. The dietary origin of fecal specimens was confirmed by use of colored markers fed with each diet, and was correlated with estimates of gastrointestinal tract transit time. A modified guaiac paper test and an o-tolidine tablet test were performed on each specimen.

Of 59 specimens, 4 were positive for occult blood, using the o-tolidine tablet test. Three positive results were associated with a mutton-based canned diet, and 1 positive result was associated with a canned beef-based diet. Of 59 specimens, 11 were positive for occult blood, using the modified guaiac paper test. Four positive results were associated with the mutton diet, and 3 positive results were associated with the beef diet. Of the remaining 5 diets, 4 caused 1 positive reaction.

Results were inconsistent with the null hypothesis that the distribution of positive occult blood test results is not affected by diet (P < 0.025), and indicate that diet can affect the specificity of peroxidase-based tests for detection of occult blood in canine feces. Diet modification prior to testing is recommended.
Reference serum biochemical values for emus and ostriches
Authors: Okotie-Eboh G. , Bailey C. A. , Hicks K. D. , Kubena L. F.
Published: January 2024

Reference serum biochemical values were determined in blood samples from 15 male, 18 female, and 4 unsexed emus (Dromaius novaehollandiae) 1 to 48 months old. Serum biochemical values also were obtained for 19 male, 26 female, and 4 unsexed ostriches (Struthio camelus) 1 to 60 months old. Parametric (mean ± 2 sd) and nonparametric (fifth to 95th percentile) reference ranges and linear trends as influenced by age were determined for enzyme activities and concentrations of glucose, inorganic phosphate, bun, uric acid, creatinine, triglyceride, cholesterol, total protein, and albumin. Species differences for all analytes, except cholesterol and inorganic phosphate concentrations, were detected. Creatine kinase values in ostriches were higher than those in emus. There were no linear relationships between age and analyte values in emus, and sex did not significantly (P < 0.05) affect the values in emus. Analyte values in ostriches tended to increase with age, but cholesterol, creatine kinase, inorganic phosphate, and alkaline phosphatase concentrations decreased with age. Glucose, triglyceride, γ-glutamyltransferase, and cholinesterase concentrations in ostriches were not linearly associated with age. Age had a greater effect on the analyte values of female ostriches than it did on male ostriches. Concentrations generally increased with age in female ostriches, except for cholesterol, cholinesterase, inorganic phosphate, and alkaline phosphatase concentrations, which decreased with age.
Hemodynamic and respiratory responses to variable arterial partial pressure of oxygen in halothane-anesthetized horses during spontaneous and controlled ventilation
Authors: Steffey E. P. , Willits N. , Woliner M.
Published: January 2024

Cardiovascular and respiratory responses to variable Pao2 were measured in 6 horses anesthetized only with halothane during spontaneous (sv) and controlled (cv) ventilation. The minimal alveolar concentration (mac) for halothane in oxygen was determined in each spontaneously breathing horse prior to establishing Pao2 study conditions—mean ± sem,0.95 ± 0.03 vol%. The Pao2 conditions conditions of > 250, 120, 80, and 50 mm of Hg were studied in each horse anesthetized at 1.2 mac of halothane and positioned in left lateral recumbency. In response to a decrease in Pao2, total peripheral resistance and systolic and distolic arterial blood pressure decreased (P < 0.05) during sv. Cardiac output tended to increase because heart rate increased (P < 0.05) during these same conditions. During cv, cardiovascular function was usually less than it was at comparable Pao2 during sv (P < 0.05). Heart rate, cardiac output, and left ventricular work increased (P < 0.05) in response to a decrease in Pao2, whereas total peripheral resistance decreased (P < 0.05). During sv, cardiac output and stroke volume increased and arterial blood pressure and total peripheral resistance decreased with duration of anesthesia at Pao2 > 250 mm of Hg. During sv, minute expired volume increased (P < 0.05) because respiratory frequency tended to increase as Pao2 decreased. Decrease in Paco2 (P < 0.05) also accompanied these respiratory changes. Although oxygen utilization was nearly constant over all treatment periods, oxygen delivery decreased (P < 0.05) with decrease in Pao2, and was less (P < 0.05) during cv, compared with sv, for comparable Pao2 values. Muscle and hepatic-derived serum biochemical values were substantially increased and evidence of depressed renal function was observed in these horses immediately after anesthesia recovery. These serum biochemical changes exceeded values in horses previously studied during prolonged halothane anesthesia in the absence of low Pao2.
Keratin and associated proteins of the equine hoof wall
Authors: Grosenbaugh D. A. , Hood D. M.
Published: January 2024

In this study, we described water-insoluble proteins extracted from the germinative regions (stratum internum and coronary band epithelium) and the cornified outer surface (stratum medium) of the equine hoof wall. Two major types of polypeptides were identified: the intermediate filaments (if) and the if-associated proteins. The if, including keratins, composed a major portion of this fraction, had electrophoretic mobilities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the range of 40 to 80 kDa, and reacted with acidic or basic keratin-specific monoclonal antibodies. Differences in the composition of keratins between germinative layers and the stratum medium were seen. Another less well-characterized group of polypeptides associated with the if also were extracted with the water-insoluble polypeptide fraction. These associated proteins had an apparent molecular weight between 10 and 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and contained a higher percentage of sulfur-containing amino acids than did the if. Water-insoluble protein fractions compared favorably with those found in other less-specialized keratinizing tissue with respect to size, immunoreactivity with monoclonal antibody, and amino acid composition.
Regional brain blood flow during prolonged submaximal exercise in ponies
Authors: Sikkes Bridget P. , Manohar Murli , Duren Stephen E. , Day Jennifer , Baker John P.
Published: January 2024

Experiments were carried out on 8 healthy ponies to examine the effects of prolonged submaximal exercise on regional distribution of brain blood flow. Brain blood flow was ascertained by use of 15-μm-diameter radionuclide-labeled microspheres injected into the left ventricle. The reference blood was withdrawn from the thoracic aorta at a constant rate of 21.0 ml/min. Hemodynamic data were obtained with the ponies at rest (control), and at 5, 15, and 26 minutes of exercise performed at a speed setting of 13 mph on a treadmill with a fixed incline of 7%. Exercise lasted for 30 minutes and was carried out at an ambient temperature of 20 C. Heart rate, mean arterial pressure, and core temperature increased significantly with exercise. With the ponies at rest, a marked heterogeneity of perfusion was observed within the brain; the cerebral, as well as cerebellar gray matter, had greater blood flow than in the respective white matter, and a gradually decreasing gradient of blood flow existed from thalamus-hypothalamus to medulla. This pattern of perfusion heterogeneity was preserved during exercise. Regional brain blood flow at 5 and 15 minutes of exercise remained similar to resting values. However, at 26 minutes of exercise, vasoconstriction resulted in a significant reduction in blood flow to all cerebral and brain-stem regions. In the cerebellum, the gray matter blood flow and vascular resistance remained near control values even at 26 minutes of exercise. Vasoconstriction in various regions of the cerebrum and brainstem at 26 minutes of exertion may have occurred in response to exercise-induced hypocapnia, arterial hypertension, and/or sympathetic neural activation.
Bacterial survival, lymph node changes, and immunologic responses of cattle vaccinated with standard and mutant strains of Brucella abortus
Authors: Cheville N. F. , Jensen A. E. , Halling S. M. , Tatum F. M. , Morfitt D. C. , Hennager S. G. , Frerichs W. M. , Schurig G.
Published: January 2024

Forty-eight cattle were used in 4 experiments; 6-week-old calves in experiments 1-3 (n = 24) and 10-month-old heifers in experiment 4 (n = 24). In experiments 1-3, 7 groups of 3 calves each were inoculated sc with 5 strains of Brucella abortus: virulent strain 2308 (2 groups), vaccine strain 19 (2 groups), and mutant strains RB51, 19Δ31K, and 19ΔSOD. Sera and lymph node tissues were examined at 2-week intervals for evidence of infection. At postinoculation (pi) week 12, 2 calves in each group were given dexamethasone for 5 days. Calves were then euthanatized and lymphoid tissue, spleen, liver, and bone marrow were examined for evidence of B abortus. Calves given strain 2308 had large numbers of bacteria in their lymph nodes, marked granulomatous lymphadenitis in the deep cortex, and loss of lymphoid cells in superficial cortical areas. In addition, they had high serum antibody titers at pi week 16. Calves given strain 19, or genetic mutants derived from strain 19, cleared bacteria from lymph nodes more rapidly, had less lymphoid destruction, and developed antibody titers that did not persist for 16 weeks. The RB51 strain (rough) was cleared most rapidly from lymphoid tissues and induced serum antibody responses only to the core of the lipopolysaccharide molecule. Treatment of calves with dexamethasone did not cause B abortus to reappear in tissues of any calves, nor did serum antibody titers increase.

In experiment 4, designed to compare the effects of age, 4 groups (n = 4) of 10-month-old heifers were given 1 B abortus strain each (19, RB51, 19Δ31K, or 19ΔSOD), using the same methods. Results of bacteriologic culturing and antibody responses were similar to those in the calves, except that strain RB51 persisted longer in heifers. Results of these studies indicated that, in cattle, the genetically engineered deletion mutants of B abortus do not cause unusual lesions, do have characteristics that closely resemble the parental strain, and could be candidates for use in a live vaccine.
Evaluation of clinical signs of disease, bronchoalveolar and tracheal wash analysis, and arterial blood gas tensions in 13 horses with chronic obstructive pulmonary disease treated with prednisone, methyl sulfonmethane, and clenbuterol hydrochloride
Authors: Traub-Dargatz J. L. , McKinnon A. O. , Thrall M. A. , Jones R. L. , Bruyninckx W. , Blancquaert A-M. B. , Dargatz D. A.
Published: January 2024

We evaluated the efficacy of 3 treatments for chronic obstructive pulmonary disease in horses: prednisone (400 mg/horse, po, daily; n = 7), methyl sulfonmethane (10 g/horse, po, q 12 h; n = 6), and clenbuterol hydrochloride (0.4 mg/horse, po, q 12 h; n = 7). A fourth group acted as controls (n = 6) and was not treated. The treatment period lasted 10 days. Each horse was a member of 2 different groups for 10 days, separated by an 18-day interval of no treatment. All horses were housed together in an outdoor pen without bedding. Horses were fed alfalfa/grass hay mix ad libitum from a large feeder. The same batch of hay was fed throughout the study. Multiple physical and laboratory variables were monitored prior to, during, and at the end of each 10-day trial period. Changes in lung sounds, respiratory effort, degree of anal movement, nasal discharge, temperature, respiratory rate, or heart rate were not significant. Changes in arterial blood gas tensions, tracheal wash or bronchoalveolar lavage cytologic findings, or phagocyte function were not significant. All horses were tachypneic and most were tachycardic. The median value for Pao2 was below normal for all horses. All tracheal wash and most bronchoalveolar lavage cytologic findings represented a suppurative response. Negative linear correlation was observed between Pao2 and degree of respiratory effort in these horses (eg,Pao2 decreased, the degree of respiratory effort increased).
Polymorphisms of a scrapie-associated fibril protein (PrP) gene and their association with susceptibility to experimentally induced scrapie in Cheviot sheep in the United States
Authors: Maciulis Alma , Hunter Nora , Wang Shiquan , Goldmann Wilfred , Hope James , Foote Warren C.
Published: January 2024

The duration of the incubation period for scrapie, a fatal transmissible neurodegenerative disorder of sheep and goats, is mainly determined by the Sip gene, which has 2 alleles (sA—susceptible and pA—resistant). A diagnostic test is not available to detect scrapie in live animals. We analyzed genomic dna extracted from frozen sheep brains collected from Cheviot sheep of the United States that had been inoculated with the SSBP/1 scrapie inoculum. Digestion of the dna with EcoRI or HindIII followed by the addition of a scrapie-associated fibril protein (PrP)-specific marker probe, yielded fragments of 6.8 (e1) and 4.0 (e3) kb, or 5.0 (h1) and 3.4 (h2) kb, respectively. Fragments e1 and h2 were associated with the histopathologic diagnosis of scrapie, and fragments e3 and h1 were associated with survival. A valine/alanine polymorphism within the PrP coding region that resulted in a BspHI site was further used to determine the genotype of these Cheviot sheep. Digestion of polymerase chain reaction fragments with BspHI resulted in an undigested fragment b– (0.840 kb), digested fragments b+ (0.460 and 0.380 kb), or both types of fragments. Survival time of b+/b+ homozygous sheep was significantly (P < 0.01) shorter (218 ± 26.0 days) than survival time for b−/b− sheep (> 700 days after inoculation). Results indicated that b+ and b− are markers for the Sip sA and pA alleles, respectively. The intermediate duration of the incubation period for heterozygous sheep (b+/b−; 342.9 ± 25.3 days) indicated that the Sip sA allele is expressed codominantly to the Sip pA allele.
Effects of three antiarthritic drugs on fibronectin and keratan sulfate synthesis by cultured canine articular cartilage chondrocytes
Authors: Steinmeyer Jürgen , Burton-Wurster Nancy , Lust George
Published: January 2024

Because articular chondrocytes are a target for drugs that can influence the integrity of cartilage, we investigated the effects of 3 antiarthritic drugs, glycosaminoglycan polysulfate, diclofenac-Na, and S-adenosylmethionine sulfate p-toluenesulfonate on total protein, fibronectin, and dna synthesis, as well as on extradomain-A fibronectin and keratan sulfate content. Glycosaminoglycan polysulfate stimulated dose-dependent incorporation of [35S]methionine into protein and fibronectin, whereas incorporation of [3H]thymidine into dna was unaffected. Total fibronectin, extradomain-A fibronectin, and keratan sulfate content were high in chondrocyte cultures treated with glycosaminoglycan polysulfate. In contrast, fibronectin and dna synthesis, as well as extradomain-A fibronectin and keratan sulfate content were unaffected by diclofenac-Na. S-Adenosylmethionine decreased dose-dependently the synthesis of fibronectin, as well as the content of fibronectin and keratan sulfate. At the highest concentration of S-adenosylmethionme tested, findings suggest that cell viability was impaired as assessed by the release of lactate dehydrogenase into the media.
Effect of titanium endoprostheses on bone mineral density measurements, using quantitative computed tomography
Authors: Markel Mark D. , Morin Richard L. , Roy Robert G. , Gottsauner-Wolf Florian , Chao Edmund Y. S.
Published: January 2024

Quantitative computed tomography has been used extensively to measure bone mineral density; particularly in the vertebral column and in the proximal portion of the femur in human beings with osteoporosis. Other potential applications of this technique include evaluation of bone adjacent to metallic endoprostheses and evaluation of fractures as they heal. Unfortunately, metal causes severe image degradation, principally seen as starburst streaking. One method used to decrease these artifacts is by imaging less-attenuating materials, such as titanium alloy. Titanium decreases image degradation sufficiently to allow accurate determination of the geometric properties of cadaveric bone. In our study, the effect of a titanium segmental endoprosthesis on bone mineral density measurement was determined by use of bone specimens from dogs and calibration standards. Titanium decreased the bone mineral density of calibration solutions from 6.8 (500 mg/cm3) to 17.7% (250 mg/cm3), and increased bone mineral density of cortical bone by 5.3%. Titanium did not affect the repeatability of these scans, indicating that the error caused by titanium was systematic and can be corrected. Our data were suggestive that quantitative computed tomography can be used to measure bone mineral density of cortical bone adjacent to titanium endoprostheses, with a predictable increase in density measurement.
Biomechanical comparison of three internal fixations for treatment of slipped capital femoral epiphysis in immature dogs
Authors: Belkoff Stephen M. , Millis Darryl L. , Probst Curtis W.
Published: January 2024

The biomechanical strength and stiffness of 3 fixation techniques used to repair acute slipped capital femoral epiphysis were evaluated in bone specimens from immature dogs. A servohydraulic testing machine was used to create slipped capital femoral epiphysis in 9 pairs of femurs by shearing the capital femoral epiphysis along the physis in a craniocaudal direction. The slip was reduced and repaired with 1, 2, or 3 double-pointed, 1.6-mm (0.062-inch) smooth pin(s) and retested. The strength and stiffness of each intact femur (which served as the control) and repaired femur were compared. Results of the study indicated that differences among the failure strengths of 1- and 2-pin fixations and their respective controls were not significant; however, the 3-pin fixation was 29% stronger than its control and was 60 and 45% stronger than the 1- and 2-pin fixations, respectively. One- and 2-pin fixations were 34 and 24% less stiff than their respective controls, whereas the stiffness of the 3-pin fixation was similar to its control. The 2- and 3-pin fixations were 48 and 76% stiffer, respectfully, than the 1-pin fixation, but were not significantly different, compared with each other.
Analysis of glycoprotein I (gI) negative and aberrant pseudorabies viral diagnostic isolates
Authors: Katz Jonathan B. , Pederson Janice C.
Published: January 2024

Glycoprotein I (gI) phenotypes and genotypes of 4 pseudorabies viral diagnostic isolates were evaluted by use of in vitro dna amplification, monoclonal antibody binding, gI-specific serodiagnostic responses, and in vivo virulence approaches. Three viruses were avirulent and did not elicit gI-specific serologic responses, react with gI-specific monoclonal antibodies, or contain gI epitope-encoding dna sequences. The fourth virus was virulent and did elicit a gI-specific serodiagnostic response. Compared with reference virulent Pseudorabies viruses, however, the fourth isoslate had reduced reactivity with a group of gI monoclonal antibodies and had a single nucleotide sequence substitution with a corresponding putative amino acid change in the epitopically dominant portion of the gI molecule. Presumably, the first 3 isolates represented diagnostic recoveries of viruses derived from gI-deleted modified-live Pseudorabies viral vaccines, whereas the fourth isolate was a virulent but gI-aberrant wild-type virus. Thoroughly assessing the gI status of pseudorabies viral diagnostic isolates was considered to be essential in evaluating the epidemiologic importance of these viruses and in monitoring the validity of gI-based vaccine companion tests now used worldwide in Pseudorabies control and eradication programs.