bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of a visual analogue scale and a numerical rating scale for assessment of lameness, using sheep as a model
Authors: Welsh Elizabeth M. , Gettinby George , Nolan Andrea M.
Published: January 2024

A study was designed to compare use of an numerical rating scale (nrs) and a visual analogue scale (vas) for subjective assessment of lameness, using sheep as a model. The nrs consisted of 5 divisions, 0, 1, 2, 3, and 4; 4 of these divisions (1–4) described lameness. The vas used a 100-mm horizontal line with vertical bars at either end; one end was labeled 'sound' and the other was labeled 'could not be more lame.' Two independent observers graded lameness in 62 sheep, and between- and within-observer differences were assessed for each scoring system to compare the nrs with the vas.

Results indicated no significant differences between the 2 observers scoring lameness, using either the vas or the nrs. The scores obtained, using the vas, were not normally distributed, although differences between scores for the 2 observers were. The nrs scores followed a normal distribution pattern. Investigation of repeated measurement for the same sheep, using both scales, revealed no significant difference between either. A comparison of the nrs and vas scores made by each observer indicated that although correlation was good (observer 1; r = 0.94; observer 2; r = 0.95), there was not perfect agreement. The maximal nrs score of 4 was associated with vas values > 68 mm, indicating that the nrs divisions did not reflect equal increases in lameness. The vas and nrs scores for each observer were highly reproducible, although they were more variable for sheep that were regarded as moderately lame.

Results indicate that although the nrs and vas compared favorably with respect to repeatability, reproducibility, and use by 2 observers, the vas is inherently more sensitive. In addition, the nrs and vas should not be used interchangeably.
Coxofemoral joint laxity from distraction radiography and its contemporaneous and prospective correlation with laxity, subjective score, and evidence of degenerative joint disease from conventional hip-extended radiography in dogs
Authors: Smith Gail K. , Gregor Thomas P. , Rhodes W. Harker , Biery Darryl N.
Published: January 2024

A 3-year prospective study of large-breed dogs (4 months to 3 years of age) was conducted to evaluate the influence of radiographic positioning and age on coxofemoral joint (hip) laxity, subjective hip score, and development of degenerative joint disease (djd). The dogs (n = 142) were breeder- or client-owned and represented 14 breeds. With dogs under heavy sedation, hips were radiographed in the standard hip-extended position and in the new compression/distraction position at 4, 6, 12, 24, and 36 months of age. The standard hip-extended radiographic view was evaluated by 3 methods: subjective evaluation by a board-certified veterinary radiologist (WHR), according to the standard 7-point Orthopedic Foundation for Animals (OFA) scoring scheme (OFA/WHR); joint laxity quantitation, using the Norberg angle (NA) method; and subjective scoring by a veterinary orthopedic surgeon for radiographic evidence of djd. The hips in the distraction radiographic view were evaluated for passive hip laxity, as measured by use of a unitless distraction index (di).

Results of the study indicated that at a specific age (4, 6, 12, 24, or 36 months), all methods of hip evaluation correlated with each other at a moderate level (P < 0.05). The strength of contemporaneous correlation tended to increase with age of evaluation. Longitudinally, the between-method correlations were usually significant (P < 0.05), but not at a sufficiently high level to permit reliable between-method prediction. Prospective intraclass (within-method) statistical analysis of the various hip-scoring methods indicated that di was superior to NA and OFA/WHR in comparability of score over time. The intraclass correlation coefficient ranged from 0.55 to 0.91 for di in contrast to 0.40 to 0.78 for NA, and 0.06 to 0.39 for OFA/WHR over the age intervals of the study. For reference, the highest Kappa of 0.39 for the subjective OFA/WHR scoring reflected a maximal level of agreement between time intervals, only slightly better than chance. The associated large error questions the predictive use of the 7-point, subjective hip-scoring scheme, particularly prior to the age of 2 years.
Sequential study of pancreatic structure and function during development of pancreatic acinar atrophy in a German Shepherd Dog
Authors: Westermarck Elias , Batt Roger M. , Vaillant Camille , Wiberg Maria
Published: January 2024

Sequential assessments of pancreatic structure and function were performed on a female German Shepherd Dog bred from parents with exocrine pancreatic insufficiency (epi), to monitor development of pancreatic acinar atrophy in this breed. Determinations of serum trypsin-like immunoreactivity (tli), results of N-benzoyl-l-tyrosyl-p-aminobenzoic acid test, fecal soy bean stimulation test (sst), and gross and histologic examinations of the pancreas did not provide evidence of exocrine pancreatic disease up to 13 months of age. However, electron microscopy revealed degenerative abnormalities of acinar cells that were already apparent at 6 weeks and became more extensive with age. Examination of the pancreas at 22 months of age also indicated no gross or histologic abnormalities, but electron microscopy revealed widespread degenerative changes, including dilatation of the rough endoplasmic reticulum and extensive fusion of zymogen granules affecting most of the acinar cells. Serum tli concentration was markedly reduced at that time, indicative of epi, but the dog remained healthy and results of the sst were normal. Within 1 month, the dog had developed clinical signs of epi, and not only serum tli concentration, but also results of the N-benzoyl-l-tyrosyl-p-aminobenzoic acid test and sst were compatible with severe loss of exocrine pancreatic tissue. This loss was confirmed by gross and histologic examination of the pancreas at 25 months, which revealed typical features of pancreatic acinar atrophy, including scattered and disorganized exocrine cells in the small remnants of pancreatic tissue. These findings indicate that in German Shepherd Dogs, pancreatic acinar atrophy may involve interference with normal intracellular processing of zymogen granules, which precedes progressive and eventual rapid loss of exocrine pancreatic tissue.
Effect of age on theophylline pharmacokinetics in dogs
Authors: Alberola Jordi , Pérez Yolanda , Puigdemont Ana , Arboix Margarita
Published: January 2024

Differences between neonatal and adult animals in their response to drugs can usually be attributed to altered disposition processes. Effect of age on the pharmacokinetics of theophylline was determined after IV administration of the drug to 10 groups of dogs at 1, 2, 3, 4, 8, 12, 16, 24, 52, and 104 weeks of age.

Plasma theophylline concentration curves for all groups were adjusted to a biexponential kinetic, with rapid initial distribution phase and slower elimination phase. It also was noticed that young dogs have a slower elimination half-life (1 week old, t1/2β = 987 minutes) than do older animals (8 weeks old, t1/2β = 138 minutes). The values then plateaued until 16 weeks of age, increasing slightly at more advanced age (104 weeks old, t1/2β = 282 minutes). A similar pattern was followed with respect to clearance (1-week-old pups, Cl = 1.17 ml/min/kg of body weight), which increased progressively to reach a value of 7.09 ml/min/kg at 16 weeks of age, then decreased to 3.5 ml/min/kg at 104 weeks of age. Volume of distribution β, in relation to body weight, was not significantly different between age groups (between 1.2 and 1.6 L/kg; P ≤ 0.03).

Theophylline biotransformation mechanisms may be mainly responsible for Cl and t1/2β variations. This leads us to suggest that quantitative and qualitative modifications in the P-450 mono-oxygenase system are responsible for the variations observed in pharmacokinetic variables of theophylline between dogs of different ages.

These findings may have clinical relevance with regard to the therapeutic range of theophylline. For this reason, dosage should be carefully adjusted in younger animals.
Effect of polysulfated glycosaminoglycan on osteoarthritic equine articular cartilage in explant culture
Authors: Caron J. P. , Toppin D. S. , Block J. A.
Published: January 2024

Middle carpal cartilage explants from 4 horses with mild osteoarthritis involving that joint were maintained in tissue culture to test the effects of a polysulfated glycosaminoglycan (psgag) on proteoglycan synthesis and degradation. Cultures were exposed to 0.025 or 25 mg of psgag/ml for 48 hours, after which the medium was replaced with medium containing similar doses of psgag and 35S. Subsequently, the sulfated proteoglycan content of the medium and extracts of the explants was measured. Gel filtration chromatography was used to estimate the size and to purify the principal, large proteoglycan monomer, which was further characterized by digestion, using glycosidic enzymes. In a second experiment, explants were incubated with 35S for 48 hours, and were subsequently exposed to the same concentrations of the psgag for an additional 48 hours. The amount of remaining labeled proteoglycan was determined for culture medium and cartilage extracts. Gel filtration chromatography was used to assess the hydrodynamic size of the large proteoglycan monomer. Aliquots of proteoglycans from the second experiment were incubated in high-molecular weight hyaluronate and chromatographed to assess reaggregation.

Polysulfated glycosaminoglycan caused a significant (P ≤ 0.04) decrease in sulfated proteoglycan synthesis by cartilage explants. Radioactive proteoglycan content in explants labeled prior to exposure to psgag were similar. Large proteoglycan monomer size was similar in both experiments (median partition coefficient [KAV] = 0.40), and was not influenced by psgag treatment. Prelabeled explants exposed to hyaluronate and chromatographed under associative conditions had similar proportions of the radiolabel eluting as proteoglycan aggregate. Enzymatic digestion of newly synthesized large monomer revealed a mild dose-dependent increase in the proportion of keratan sulfate substitution on core protein. It was concluded that psgag in vitro, at the dosages evaluated, caused a decrease in proteoglycan synthesis, had little effect on labeled proteoglycan degradation, did not influence the size of large monomer, and caused a modest increase in the concentration of keratan sulfate in proteoglycans synthesized by osteoarthritic equine chondrocytes.
Effects of a 44-day administration of phenobarbital on disposition of clorazepate in dogs
Authors: Forrester S. Dru , Wilcke Jeff R. , Jacobson John D. , Dyer Karen R.
Published: January 2024

The disposition of clorazepate, a benzodiazepine anticonvulsant, was determined in dogs after administration of a single oral dose of clorazepate (2 mg/kg of body weight) and after oral administration of clorazepate (2 mg/kg, q 12 h) concurrently with phenobarbital (5 mg/kg, q 12 h) for 44 consecutive days. Serum concentrations of nordiazepam, the active metabolite of clorazepate, were measured. After a single oral dose of clorazepate, maximal nordiazepam concentrations ranged from 569.6 to 1,387.9 ng/ml (mean, 880.2 ± 248.9 ng/ml) and were detected 16.8 to 131.4 minutes (mean, 85.2 ± 36 minutes) after dosing. After administration of phenobarbital for 44 consecutive days, maximal nordiazepam concentrations were significantly (P < 0.01) lower, ranging from 209.6 to 698.5 ng/ml (mean, 399.3 ± 155.6 ng/ml) at 68.4 to 145.8 minutes (mean, 93 ± 25.8 minutes) after dosing. Mean area under the curve (AUC) on day 1 (mean, 3.37 ± 0.598 ng·min/ml) was significantly (P < 0.001) greater than AUC on day 44 (1.66 ± 0.308 ng·min/ml). Oral clearance was significantly (P < 0.01) greater on day 44 (12.44 ± 2.55 ml/min/kg), compared with that on day 1 (6.16 ± 1.35 ml/min/kg). Values for area under the first moment curve, oral volume of distribution, mean residence time, and elimination half-life were not significantly altered by concurrent administration of phenobarbital.

Administration of phenobarbital altered the disposition of clorazepate such that the amount of nordiazepam in circulation during each dose interval was significantly reduced. Adequate control of seizures in epileptic dogs, therefore, may require higher dosages of clorazepate when it is coadministered with phenobarbital.
Comparison of the properties and concentrations of the isoforms of retinol-binding protein in animals and human beings
Authors: Burri Betty J. , Neidlinger Terry R. , Zwick Harry
Published: January 2024

We used size-exclusion high-performance liquid chromatography (hplc) to investigate the properties of the 2 isoforms of vitamin A-containing (holo) retinol-binding protein (rbp) in animals: the form that is bound to transthyretin (holo-ttr-rbp), and the form that does not bind to ttr (holo-free rbp). We also used radial immunodiffusion to measure immunologically active rbp (apo + holo rbp). We compared the isoforms of rbp in animals with those of human beings to determine which animal is the best model of human rbp. Size-exclusion hplc detected holo-free and holo-ttr-rbp in every animal species studied. Apparent concentration of holo-ttr-rbp varied among species: that of rabbits and dogs > > that of apes, sheep, goats, monkeys, rhinoceroses, felids, rats, human beings, and deer > that of pigs, zebra, and bison > that of penguins. Dogs have unusual rbp chromatograms; they have high concentration of rbp, but also appear to transport much of their vitamin A on proteins other than rbp. Human rbp antibody preparations could detect apo + holo rbp immunologic activity only in apes, monkeys, and felids. Apes and monkeys appeared to have complete cross-reactivity to human rbp antibodies. Felids may have substantial, but partial, cross-reactivity. Apes and monkeys appear to be the most relevant animal models for study of human rbp transport. However, there is a need for less-expensive models. Further research is needed, but in the interim, rats or sheep may be satisfactory for some purposes.
Determination of hemagglutination-inhibition titers to influenza A virus in porcine sera by use of an enzyme-linked immunosorbent assay
Authors: Lee Brian W. , Bey Russell F. , Baarsch Mary J. , Morrison Robert B. , Freese Wayne
Published: January 2024

An elisa-based method to estimate hemagglutination-inhibition (hi) titer was developed. Subtype specificity was obtained by using purified H1 and H3 hemagglutinin antigens. Using the linear relation that exists between elisa and hi methods, regression lines for HIN1- and H3N2-monospecific porcine antisera were constructed. Approximation of actual hi titer could be obtained from insertion of elisa values into the appropriate regression line. The hi estimations were within 50% of the actual measured hi value 84% of the time. In young pigs that had suckled immune sows, use of this elisa revealed estimated hi titer > 320 at 2 and 4 weeks of age. After a typical farm outbreak of influenza A/swine (HIN1), estimated hi titers remain high for 4 to 6 months. Subtype-specific estimation of the distribution frequency of positive influenza A (HIN1 or H3N2) results for sera from swine in regional herds indicated that 31.3 and 7.4% of the swine tested were positive (hi > 41) for H1N1 and H3N2, respectively. From these observations, we conclude that in many circumstances, an elisa-based hi estimation method could be used as a substitute for the hi test.
Evaluation of bacterins containing three predominant phage types of Salmonella enteritidis for prevention of infection in egg-laying chickens
Authors: Barbour Elie K. , Frerichs Wayne M. , Nabbut Nassim H. , Poss Peter E. , Brinton Marshall K.
Published: January 2024

Six Salmonella enteritidis bacterin formulations differing in adjuvant content and whole-cell inactivation procedures were evaluated in egg-laying chickens. Chickens given S enteritidis bacterins containing modified Freund's incomplete adjuvant had greater humoral immune responses to S enteritidis than did birds given other bacterin formulations (P < 0.05). Better protection against infection by S enteritidis phage types 8, 13a, and 23 was obtained in birds vaccinated with bacterin 5. Bacterin 5 contained S enteritidis cells inactivated by 20% acetone and modified Freund's incomplete adjuvant.
Effect of phenylbutazone and repeated endotoxin administration on hemostasis in neonatal calves
Authors: Semrad Susan D. , Dubielzig Richard
Published: January 2024

Twenty newborn Holstein calves were allotted at random to 4 groups: group A received 0.9% sterile saline solution; group B received phenylbutazone (5 mg/kg of body weight, iv) and 0.9% sterile saline solution; group C received progressively increasing doses of endotoxin (0.1 to 15 μg/kg); and group D received phenylbutazone and endotoxin similarly as did calves of groups B and C, respectively. Phenylbutazone was given once daily and saline solution or endotoxin were given every 8 hours for 5 days. Clinical variables—pcv, plasma total protein and fibrinogen concentrations, platelet count, prothrombin time, activated partial thromboplastin time, and fibrin degradation products concentration were measured at 24-hour intervals. Necropsy was performed on each calf.

Phenylbutazone suppressed the clinical response to endotoxin challenge until large doses (7.5 to 15 μg/kg) were administered. Calves of groups C and D remained stable until they abruptly developed severe dyspnea necessitating euthanasia. Thrombocytopenia and leukopenia developed after the initial endotoxin dose. Prothrombin time was prolonged and pcv suddenly decreased at 96 hours. Necropsy revealed consistent lesions in the vascular endothelium and lungs. Phenylbutazone administration did not enhance or ameliorate endotoxin-induced hemostatic alterations or pathologic lesions.
Production of monoclonal antibodies specific for antigens derived from tissue of chinook salmon (Oncorhynchus tshawytscha) affected with plasmacytoid leukemia
Authors: Newbound Garret C. , Markham Robert J. F. , Speare David J. , Saksida Sonja M. , Després Beatrice M. , Horney Barbara S. , Kibenge Frederick S. , Sheppard Judith A. , Wright Glenda M. , Kent Michael L.
Published: January 2024

Two distinct monoclonal antibodies (mab) were prepared for testing with kidney, spleen, and retrobulae tissue imprints made from chinook salmon (Oncorhnchus tshawytscha) affected with plasmacytoid leukemia. (pl). Hybridomas were prepared from mice immunized with whole and lysed cells purified from renal or retrobular pl-positive tissues, which had been obtained from naturally and experimentally infected fish from British Columbia, Canada. The mab reacted with at least 4 morphologically different cell types; of fluorescence was associated with the plasma membrane and cytoplasm. The mab also reacted with kidney imprints made from chinook salmon affected with a pl-like lymphoproliferative disease in California, indicating that these 2 diseases might be caused by a similar agent. The mab did not react with any of the kidney or spleen imprints made from wild chinook salmon collected from a river in Ontario, Canada
Effects of subject velocity on force plate-measured ground reaction forces in healthy Greyhounds at the trot
Authors: Riggs C. M. , DeCamp C. E. , Soutas-Little R. W. , Braden T. D. , Richter M. A.
Published: January 2024

Force plate gait analysis was used to study the effects of subject velocity on ground reaction forces. Seven adult Greyhounds were trotted at 3 distinct velocities: 1.5 to 1.8 m/s, 2.1 to 2.4 m/s, and 2.7 to 3.0 m/s. Forelimb and hind limb peak vertical forces increased with increase in velocity (P < 0.05). Forelimb and hind limb vertical impulses decreased as velocity increased (P < 0.05). Significant variations were not observed for craniocaudal or mediolateral peak forces or impulses. It was concluded that velocity significantly (P < 0.05) influenced ground reaction forces and impulses, and must be controlled in experimental design.
Effects of intra-articular chlorhexidine diacetate lavage on the stifle in healthy dogs
Authors: Anderson Mark A. , Payne John T. , Kreeger John M. , Wagner-Mann Colette C. , Schmidt Donald A. , Mann F. A.
Published: January 2024

Eight dogs were determined to be orthopedically normal on the basis of prelavage physical examination, stifle radiography, synovial fluid analysis, and force plate analysis (peak vertical force normalized for body weight, and time on the force plate). Each dog had 1 stifle randomly assigned to be lavaged with 100 ml of a commercially available 0.05% (w/v) chlorhexidine diacetate solution, and the contralateral stifle was lavaged with lactated Ringer’s solution.

Difference was not detected between the chlorhexidine diacetate and lactated Ringer’s solution-treated joints, with regard to results of synovial fluid analysis and clinical lameness evaluations on days 4 and 8 after lavage. Chlorhexidine diacetate caused a more intense synovitis than did lactated Ringer’s solution, as determined by histologic evaluation of synovial membrane specimens after necropsy on day 8; however, a difference in the intensity of toluidine blue staining of articular cartilage was not found between treatments. Chlorhexidine diacetate, as a 0.05% (w/v) solution, cannot be recommended as a joint lavage fluid until the duration of inflammatory changes in the synovial membrane are determined or until the chemical constituents of chlorhexidine diacetate causing the synovitis can be identified and removed.
Effects of concurrent administration of phenylbutazone and flunixin meglumine on pharmacokinetic variables and in vitro generation of thromboxane B2 in mares
Authors: Semrad Susan Diane , Sams Richard Alvin , Harris Orville Newton , Ashcraft Susan Marie
Published: January 2024

Flunixin meglumine and phenylbutazone are nonsteroidal anti-inflammatory drugs commonly used for the management of colic, endotoxemia, and musculoskeletal disorders in equids. Although it is not usually recommended, there appears to be an increasing trend to use nonsteroidal anti-inflammatory drugs in combination to enhance or prolong their effects. Therefore, we studied the effect of concurrent administration of flunixin (1.1 mg/kg of body weight, iv) as flunixin meglumine and phenylbutazone (2.2 mg/kg, iv) on the pharmacokinetics of each drug and on in vitro thromboxane B2 production.

Pharmacokinetic variables calculated for each drug when given alone and in combination were similar to those reported. Serum thromboxane B2 production was significantly (P = 0.05) suppressed for 12, 8, and 24 hours after administration of flunixin, phenylbutazone, and the drugs in combination, respectively. These results indicate that although concurrent administration of these drugs at the aforementioned dosages does not alter either drug disposition or clearance, it prolongs their pharmacologic effect.
Somatosensory potentials in dogs with naturally acquired thoracolumbar spinal cord disease
Authors: Poncelet Luc , Michaux Charles , Balligand Marc
Published: January 2024

Somatosensory evoked potentials (sep) were recorded at the scalp and at various levels along the lumbar and caudal thoracic parts of the spine in response to tibial nerve stimulations. The sep were observed in 24 diseased dogs, 2 with a vertebral fracture, 1 with a spinal cord tumor, 1 with a vertebral tumor, and 20 with disk herniation. Cord compression location was confirmed by myelography, laminectomy, or both. The clinical state had significant (P < 0.0001) influence on sep characteristics. The scalp-recorded sep latency changed only in association with the most severe lesions; spine-recorded sep conduction velocity was lower in association with mild lesions; scalp-recorded sep amplitude changed with lesions of intermediary severity. Because these 3 electrophysiologic variables were influenced differently by cord damage, it was possible to discriminate the various clinical grades by use of these techniques. However, dogs with signs of pain only could not be differentiated from clinically normal dogs. The evoked injury potential was observed in all but 4 diseased dogs, and its maximal amplitude corresponded, in all cases, with cord damage location. Increased duration (P < 0.05) of the spine-recorded sep was associated with longstanding problems, but not necessarily with clinically detectable malfunction. Use of sep and evoked injury potential for identifying lateralized cord damage may be of value.
Colorimetric diagnosis of prolonged bluetongue viremia in sheep, using an enzyme-linked oligonucleotide sorbent assay of amplified viral nucleic acids
Authors: Katz Jonathan B. , Gustafson Gary A. , Alstad A. David , Adler Karl A. , Moser Kathryn M.
Published: January 2024

Each of 5 US-origin serotypes of bluetongue virus (btv) was inoculated into a separate pair of sheep. The duration of each animal's ensuing viremia was monitored, using a btv serogroup-specific nested polymerase chain reaction (pcr) method and an embryonating chicken egg (ece) inoculation procedure. Mean duration of viremia was 100 and 38 days for the pcr and ece methods, respectively. This difference was significant (P < 0.001) and documents a more prolonged viremia in virus-exposed sheep than has been reported. A dual internal oligonucleotide solution hybridization procedure was developed for the rapid (2 hours) colorimetric detection and identification of btv-specific pcr products. This enzyme-linked oligonucleotide sorbent assay (elosa) relied on annealing of separate biotinylated and fluores-ceinated probes to the amplified btv nucleic acid; these complexes were captured on streptavidin-coated microtitration wells and were detected, using a horseradish peroxidase-labeled antifluorescein antibody conjugate. End-point dilution analyses of pcr products indicated that the elosa was more sensitive than gel electrophoretic or comparable colorimetric slot-blot hybridization techniques. The btv pcr-elosa system represents a more sensitive and expeditious means of diagnosing btv-induced viremia than does the ece procedure currently used. The combination of elosa with pcr should facilitate practical application of nucleic acid technology to diagnostic veterinary medicine.
Pharmacokinetics of phenylbutazone in neonatal foals
Authors: Wilcke Jeff R. , Crisman Mark V. , Sams Richard A. , Gerken Diane F.
Published: January 2024

Single doses (2.2 mg/kg of body weight) of phenylbutazone (pbz) were administered iv to 6 neonatal horses (5 to 17 hours old at time of dosing). Plasma concentrations of pbz and its metabolite oxyphenbutazone were monitored serially for 120 hours after drug administration. Pharmacokinetic variables were calculated, using 1- and 2-compartment open models. Descriptive equations from the best model for each foal were then used to derive model-independent variables describing pbz disposition. Median volume of distribution at steady-state was 0.274 L/ kg (range, 0.190 to 0.401 L/kg). Median terminal half-life was 7.4 (6.4 to 22.1) hours, and median total plasma clearance of pbz for foals in this study was 0.018 L/kg/h (range, 0.013 to 0.038 L/kg/h). Volume of distribution was larger, half-life was longer, and total clearance was lower, compared with similar values reported for administration of pbz to adult horses.
Lack of residual lung damage in horses in which Rhodococcus equi-induced pneumonia had been diagnosed
Authors: Ainsworth Dorothy M. , Beck Kathy A. , Boatwright Celeste E. , Snedden Kimberly A. , Rebhun William C.
Published: January 2024

The effect of prior Rhodococcus equi-induced pneumonia on pulmonary health was investigated in 5 horses (< 24 months old) using endoscopy, radiography, hematologic and bronchoalveolar lavage analyses, and pulmonary function testing. Rhodococcus equi-induced pnuemonia had been diagnosed in principal horses when they were foals. Diagnosis was based on positive results of transtracheal aspiration and thoracic radiography at the time of initial clinical examination. Results of reevalution of the respiratory system of these horses (R + ) were compared with those of 5 age-matched healthy horses (R −) that lacked clinical or historical evidence of foalhood pneumonia.

Significant differences in variables between the 2 groups of horses were not evident. In both groups, most horses had radiographic evidence of an accentuated bronchointerstitial pattern, although results of analysis of bronchoalveolar lavage specimens were normal and mononuclear cells predominated. Variability in results of the pulmonary function tests was observed within and between the 2 groups of horses. Only normalized dynamic lung compliance was slightly lower in the previously infected horses, but this difference was not significant. We concluded that horses previously infected with and successfuly treated for R equi-induced pneumonia do not have detectable evidence of residual lung damage.
Free segmental paw pad grafts in dogs
Authors: Swaim Steven F. , Bradley Dino M. , Steiss Janet E. , Powers Robert D. , Buxton Donald F.
Published: January 2024

After removal of 1 metatarsal pad and formation of a granulation tissue bed, free segmental 6- × 8-mm grafts from digital pads were sutured into recessed same-size recipient sites in the granulation tissue. In 5 dogs, the grafted area had been denervated by excision of a segment of the tibial nerve at the level of the tarsus. The grafted area was not denervated in the remaining 5 dogs. In both groups of dogs, the grafts placed around the periphery of the wound healed, blocked ingrowth of delicate epithelium from the surrounding skin, and provided a tough keratinized epithelium that covered the wound's center. As healing progressed, the grafts coalesced as the wounds contracted. Weight bearing resulted in graft expansion to provide functional weight-bearing tissue.

Dogs of the denervated group had clinical and histologic evidence of collateral sensory reinnervation of the denervated area. However, with the exception of 1 dog, results of sensory nerve action potential tests indicated that reinnervation may not have been by way of regeneration across the excisional gap in the nerve.

Evaluation of reinnervation of the tibial autonomous zone in 2 additional dogs revealed clinical evidence that collateral reinnervation began between 19 and 28 days after nerve excision and progressed proximad to distad. Results of sensory nerve action potential tests indicated that reinnervation may not have been via regeneration across the excision site. Results of fluorescent tracer studies did not have positive findings regarding the route of collateral reinnervation.

Segmental paw pad grafts can be used effectively to provide weight-bearing tissue on a dog's limb. With local nerve damage on the distal portion of the limb, collateral innervation can grow into the area to reinnervate tissues, including pad grafts.
Effects of dietary sodium intake on blood pressure measurements in partially nephrectomized dogs
Authors: Greco Deborah S. , Lees George E. , Dzendzel Gerald , Carter Alice B.
Published: January 2024

Systolic, diastolic, and mean arterial blood pressure were measured by femoral artery puncture every other day in 2 groups (n = 4) of partially nephrectomized (approx 75%) dogs fed 2 concentrations of dietary sodium beginning 9 weeks after partial nephrectomy was completed. In a double crossover design, dogs were fed a low-sodium (0.18% sodium on a dry-weight basis) or high-sodium (1.3% sodium on a dry-weight basis) diet in 2 sequences (l/h/l or h/l/h) for 3 consecutive 4-week observation periods. Significant effect of sequence was found in dogs fed the l/h/l sequence, compared with those fed the h/l/h sequence. Systolic blood pressure was significantly (P < 0.05) increased in dogs fed the l/h/l sequence (175 ± 16 mm of Hg), compared with dogs fed the h/l/h sequence (156 ± 14 mm of Hg). Mean arterial blood pressure was higher, but not significantly different, for the l/h/l sequence (116 ± 8 mm of Hg) vs the h/l/h sequence (109 ± 6 mm of Hg). Significant difference in diastolic pressure was not observed between the l/h/l (86 ± 10 mm of Hg) and h/l/h (86 ± 10 mm of Hg) sequences. Restricted sodium intake (0.18% sodium on a dry-weight basis) was associated with moderate systolic hypertension in dogs with experimentally induced chronic renal disease. Acute fluctuations in dietary sodium intake had no apparent immediate effect on blood pressure in dogs with this mild to moderate degree of renal dysfunction.
Substance P immunohistochemical study of the sensory innervation of normal subchondral bone in the equine metacarpophalangeal joint
Authors: Nixon Alan J. , Cummings John F.
Published: January 2024

Serial sections of bone and soft tissue from the metacarpophalangeal joints of 2 mature and 2 immature horses were evaluated for substance P immunoreactive sensory nerve fibers. Formalin-fixed specimens were sectioned, either nondemineralized or demineralized with formic acid or edta. Rabbit antiserum to substance P (sp) was used in the streptavidin-biotin-peroxidase complex method for immunolocalization of sp antigen, and staining with 3,3′- diaminobenzidine was used for permanent identification of sp fibers. Abundant sensory nerve fibers were identified in the joint capsule, synovial membrane subintimal layers, collateral ligaments, suspensory ligament and distal sesamoidean ligament attachments to the sesamoid bones, and the periarticular periosteal layers. Sparse sp-immunoreactive nerve fibers were found in subchondral bone plates of the metacarpus, proximal first phalanx, and dorsal articular surface of the sesamoid bones. Most sp fibers were associated with blood vessels in the small cancellous spaces and haversian canals of the subchondral bone. The deeper marrow spaces contained increased numbers of sp sensory fibers; a few appeared in small groups and as several sp-immunoreactive fibers in a larger nerve. Cortical bone contained only a few sp fibers in the haversian canals. Substance P fibers were not identified in the osteocytic lacunae, canaliculi, or the bony lamellae of the haversian systems of the subchondral bone plate, and its extension to the metaphyseal and diaphyseal cortical bone. Equine metacarpophalangeal joint soft tissues have an abundant sensory nerve supply, similar to that of other species. However, the subchondral bone plate also has sparse sensory nerve fibers, which is a unique finding, and may help explain signs of bone pain associated with disease states of the fetlock.
Immunopathologic study and characterization of the phenotype of transformed cells in sheep with bovine leukemia virus-induced lymphosarcoma
Authors: Murakami K. , Aida Y. , Kageyama R. , Numakunai S. , Ohshima K. , Okada K. , Ikawa Y.
Published: January 2024

We used monoclonal antibodies and immunohistologic examination of lymph nodes, to elucidate the pathogenesis of lymphosarcoma induced by infection with bovine leukemia virus (blv). The superficial cervical lymph nodes from 3 blv-infected but apparently healthy sheep and 5 sheep with fullblown lymphosarcoma were examined. We also investigated the integration of bovine leukemia provirus by use of Southern blotting. In lymph nodes from sheep lacking clinical signs of infection, in which the provirus had been integrated at multiple sites in the genome, many large hypertrophic follicles were observed in the cortex. These follicles had germinal centers consisting of CD4+T cells and B cells that expressed surface IgM (slgM) and major histocompatibility complex (mhc) class-II antigens, but not B cell-specific B2 molecule. The percentage of CD4+T cells in the cortex was significantly (P < 0.05) higher than that of the controls and sheep with lymphosarcoma. In all sheep with lymphosarcoma, the lymph nodes were completely destroyed by proliferating neoplastic cells, and in addition, small atrophic follicles, which consisted of normal B-cell marker-positive cells, were seen near the trabecula and the subcapsule. In these instances, neoplastic cells appeared to be a monoclonal population derived from a single CD5− B-cell lineage and to be classified as 2 types, CD5−CD4−CD8−B2+MHC class-II+sIgM+ and CD5−CD4−CD8−B2+mhc class-II+sIgM−. Moreover, CD8+T cells infiltrated diffusely throughout the tumorous lymph nodes apart from the atrophic follicles, and CD4+T cells were observed around atrophic follicles. Both types of T cells were small-size, normal lymphocytes with round and noncleaved nuclei, and were apparently non-neoplastic cells. In fact, after separation by use of a panning method, it seems that, in blood mononuclear cells from BLV-infected sheep without clinical signs of infection, but in lymphosarcomatous stages, the proviral genome was integrated only in B cells and not in T cells. Thus, we conclude that the host's immune response may be still maintained at a lymphosarcomatous stage.
Differentiation of Mycoplasma hyopneumoniae, M flocculare, and M hyorhinis on the basis of amplification of a 16S rRNA gene sequence
Authors: Stemke Gerald W. , Phan Robert , Young Theresa F. , Ross Richard F.
Published: January 2024

To differentiate Mycoplasma hyopneumoniae, the cause of mycoplasmal pneumonia in pigs, from M flocculate and M hyorhinis, an assay, using the polymerase chain reaction to amplify a segment of the 16S rrna gene sequence, was developed. The assay was found to be useful for identification of field isolates, as well as for identification of laboratory-adapted strains. Amplification of dna from M hyopneumoniae and M flocculare resulted in products of 200 and 400 base pairs, respectively. The dna from M hyorhinis was not amplified. The assay was sensitive enough to detect as little as 1,000 genome equivalents of M hyopneumoniae and M flocculare dna. Sensitivity was increased 100-fold by increasing the concentration of magnesium ion in the reaction buffer from 2 to 4 mM; however, dna from M hyorhinis was also amplified under these conditions. The DNA from several walled bacteria and from other mycoplasmas was also tested, but none of these dna samples was amplified, suggesting that the assay was specific for porcine mycoplasmas.
Effect of in vitro and in vivo migration of bovine neutrophils on binding and expression of Fc receptors for IgG2 and IgM
Authors: Worku Mulumebet , Paape Max J. , Filep Renee , Miller Robert H.
Published: January 2024

Binding of endogenous and exogenous homologous IgG2 and IgM to bovine neutrophils before and after in vitro migration through micropore filters, and in vivo migration through mammary tissues after intramammary injection of endotoxin was evaluated by use of flow cytometry. Immunoglobulin binding to neutrophils at 4 and 37 C was also evaluated. Before and after in vitro migration, neutrophils with endogenously bound IgG2 and IgM averaged 1 and 2% and 23 and 7%, respectively. Before and after in vivo migration, IgG2 and IgM binding averaged 1 and 7% and 26 and 15%, respectively. Before and after in vitro migration, binding of purified IgG2 and IgM averaged 75 and 67% and 8 and 24%, respectively. Before and after in vivo migration, percentage of neutrophils binding purified IgG2 and IgM averaged 92 and 98% and 54 and 70%, respectively. When serum was used as a source of exogenous immunoglobulins, binding of total IgG after in vitro migration increased from 5% to 28% and of IgM from 4% to 20%. After in vivo migration, binding increased from 21% to 47% and from 24% to 56%, respectively. Exogenous binding of IgG2 at 4 and 37 C averaged 75 and 84%, and binding of IgM averaged 8% at either temperature. Endogenous IgG2 was unaffected by temperature; however, binding of IgM decreased from 23% at 4 C to 2% at 37 C. These data indicate that endogenous binding was higher for IgM before migration than after migration, in vitro and in vivo. Furthermore, migration in vivo through cellular matrices induced receptor upregulation for IgG and IgM. Source and concentration of ligand and serum components, other than immunoglobulins, appeared to contribute to receptor expression and availability. Neutrophils that were exposed to endotoxin and migrated into milk expressed more receptors than did unstimulated and nonmigrating neutrophils. The association of IgM with its receptor was temperature-dependent.
Resistance of Chinese Meishan, Fengjing, and Minzhu pigs to the K88ac+ strain of Escherichia coli
Authors: Michaels Rita D. , Whipp Shannon C. , Rothschild Max F.
Published: January 2024

The microscopic brush border membrane adherence assay was used to determine resistance (nonadherence) and susceptibility (adherence) of Chinese pigs (n = 289) to the K88ac+ strain of Escherichia coli-mediated disease. This study estimates prevalence of resistance to diarrheal disease in multiple family lines (no common ancestry for a minimum of 3 generations) for the Chinese Meishan, Fengjing, and Minzhu breeds. Results of in vitro assays indicate that pigs of the Meishan breed are highly resistant (nonadherent) to K88ac+ E coli-mediated disease. The gene conferring susceptibility to K88act E coli-mediated disease exists at low frequency in pigs of the Minzhu breed. Minzhu-type (crossbred) pigs of both phenotypes (susceptible and resistant) were identified in ratios consistent with a 1-locus gene model. Given that all susceptible pigs were from 1 site, frequency of susceptibility within this Minzhu population is estimated at 8%. Inheritance within the Fengjing breed is still unclear because a weakly adherent phenotype, as well as the resistant phenotype, was identified. The weakly adherent phenotype was observed in pigs derived from multiple family lines. Expression of the weakly adherent phenotype in terms of susceptibility to disease is not known at this time.
Antigenic composition of Pasteurella haemolytica serotype-1 supernatants from supplemented and nonsupplemented media
Authors: Mosier Derek A. , Simons K. René , Chengappa M. M. , Confer Anthony W.
Published: January 2024

Supernatant preparations containing antigens produced by Pasteurella haemolytica serotype 1 grown in nonsupplemented RPMI 1640 medium and 3 grown in supplemented RPMI 1640 media were evaluated. Antigens were detected by immunoblotting each supernatant preparation with sera from 20 cattle with various degrees of resistance to experimentally induced pneumonic pasteurellosis. Antigen antibody bands at 49 and 30 kd were correlated with resistance in all 4 media. A 66-kd antigen-antibody band was correlated with resistance in 2 media, and antigen-antibody bands at 100 and 16 kd were correlated with resistance in 1 medium each. These results indicated that the number and relative amount of resistance-associated antigens in P haemolytica supernatants can be optimized on the basis of type of growth medium used.
Holding power of orthopedic screws in the large metacarpal and metatarsal bones of calves
Authors: Blikslager Anthony T. , Bowman Karl F. , Abrams C. Frank , Seaboch Timothy R. , Hunt Elaine L.
Published: January 2024

Holding power was determined for various orthopedic screws in bones of calves. Holding power was defined as maximal tensile force required to remove a screw divided by thickness of bone engaged by the screw (kKN/mm). Comparative pull-out tests were performed, using pairs of large metacarpal or metatarsal bones from calves aged 3 to 14 days. Comparisons were made of the holding power of 6.5-mm fully threaded cancellous screws and 5.5-mm cortical screws in the proximal and distal metaphyses, and of 4.5-mm and 5.5-mm cortical screws in the diaphysis. Sixteen repetitions of each comparative trial were performed.

There was no statistically significant difference in the holding power of 4.5- and 5.5-mm cortical screws in the diaphysis. There was no significant difference in the holding power of 5.5-mm cortical and 6.5-mm fully threaded cancellous screws in the proximal metaphysis. In the distal metaphysis, 6.5-mm fully threaded cancellous screws had significantly (P < 0.001) greater holding power than did 5.5-mm cortical screws. There was no significant difference between the mean holding power of 5.5-mm cortical screws in the proximal metaphysis and 5.5-mm cortical screws in the distal metaphysis. There was significantly (P < 0.01) greater mean holding power of 6.5-mm cortical, fully threaded cancellous screws in the distal metaphysis, compared with the proximal metaphysis.
Evaluation of laser Doppler flowmetry for measuring coronary band and laminar microcirculatory blood flow in clinically normal horses
Authors: Adair Henry S. , Goble Dallas O. , Shires G. M. H. , Sanders W. L.
Published: January 2024

Once daily for 3 days, laser Doppler flowmetry was used in 5 healthy, nonsedated adult horses to evaluate coronary band and laminar microcirculatory blood flow (mbf) in both forelimbs. The coronary band had significantly (P < 005) higher mbf than did the laminae on the days evaluated. Significant variation in mbf was not found over the 3-day measurement period in any one site. Significant (P < 0.05) variation was found in coronary band mbf among horses. This variation was not observed in laminar mbf. On occlusion of the digital arteries at the level of the fetlock, marked decrease in coronary band and laminar mbf was observed. Twenty minutes after iv administration of acetylpromazine, marked increase in coronary band and laminar mbf was observed. The technique was easily performed in standing nonsedated horses, did not inflict discomfort, lacked complications, and measurements were repeatable. This technique provides an index of digital mbf, either intermittently or continuously, avoiding introduction of invasive variables associated with other techniques.
Activity of diclazuril against Toxoplasma gondii in cultured cells and mice
Authors: Lindsay David S. , Blagburn Byron L.
Published: January 2024

The capability of diclazuril, a benzeneacetonitrile anticoccidial agent, to inhibit development of tachyzoites of Toxoplasma gondii was examined in cultured human foreskin fibroblast cells and in Hsd:ICR mice. Treatment of infected cell cultures with 10.0, 1.0, 0.1 or 0.01 μg of diclazuril/ml for 3 days resulted in > 99% reduction in tachyzoite counts, compared with controls. Treatment with 0.005 μg of diclazuril/ml resulted in > 97% reduction in tachyzoite counts, compared with controls. Treatment of host cells with 10.0, 1.0, 0.1, and 0.01 μg of diclazuril/ml for 24 hours prior to tachyzoite inoculation resulted in 97, 31, 0, and 0% reduction in tachyzoite counts, compared with controls, respectively, 3 days after inoculation. All mice that were treated orally with 10.0 mg of diclazuril/kg of body weight and 80% of mice treated orally with 1.0 mg of diclazuril/kg 1 day prior to and for 10 days after tachyzoite inoculation were protected against acute toxoplasmosis. Mice treated with 10.0 mg of diclazuril/kg did not develop protective immunity, whereas mice treated with 1.0 mg of diclazuril/kg survived challenge exposure.