bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular characteristics of equine stromelysin and the tissue inhibitor of metalloproteinase 1
Authors: Richardson Dean W. , Dodge George R. 
Published: January 2024

Abstract

Objective
To clone the entire coding sequence of equine matrix metalloproteinase-3 (MMP-3, stromelysin) and tissue inhibitor of metalloproteinase-1 (TIMP-1 ) and compare their nucleotide and amino acid sequences with those of MMP-3 and TIMP-1 from other species.

Samples
Articular cartilage harvested from the joints of 4 foals, 2 yearlings, and 3 adult horses.

Procedure
A cDNA library was constructed from mRNA extracted from equine chondrocytes. The library was screened and clones selected that contained the cDNA for MMP-3 and TIMP-1. The cDNA was sequenced and the nucleotide and deduced amino acid sequences compared with known sequences in other species. Northern blot analysis was performed, using the resulting cDNA clones.

Results
An 1803-bp cDNA for MMP-3 including the entire coding sequence of 1434 bases was cloned and sequenced. A 744-bp cDNA for TIMP-1 including the entire coding sequence of 624 bases was cloned and sequenced. Northern analysis revealed MMP-3 to hybridize to a single mRNA species at approximately 2.1 kb. TIMP-1 hybridized to a single mRNA species at approximately 0.8 kb.

Conclusions
MMP-3 and TIMP-1 were highly homologous to that of other species at the nucleotide and amino acid level although each had unique residues in part of the peptide that is generally conserved.

Clinical Relevance
Understanding the molecular structure of MMP-3 and TIMP-1 and the availability of their cDNA should allow a more detailed understanding of their balance in cartilage and the degradative processes in joint disease. (Am J Vet Res 1998; 59:1557-1562)
Effects of exercise and EDTA administration on blood ionized calcium and parathyroid hormone in horses
Authors: Aguilera-Tejero Escolástico , Garfia Bartolomé , Estepa José C. , López Ignacio , Mayer-Valor Rafael , Rodríguez Mariano 
Published: January 2024

Abstract

Objective
To determine effects of exercise on blood ionized calcium (Ca2+) and plasma parathyroid hormone (PTH) concentrations in horses and to compare the effects of exercise-induced and EDTA-induced hypocalcemia on PTH secretion.

Animals
17 horses entered in a show jumping competition and 5 horses given EDTA.

Procedure
Blood Ca2+ and plasma PTH concentrations were measured before and after exercise in the 17 horses entered in the jumping competition. In the other 5 horses, concentrations were measured during infusion of EDTA IV.

Results
Exercise resulted in a significant decrease in blood Ca2+ concentration and a significant increase in plasma PTH concentration, and blood Ca2+ concentration was correlated with plasma PTH concentration. Administration of EDTA resulted in hypocalcemia and an increase in PTH concentration. For the same decrease in Ca2+ concentration, magnitude of the exercise-induced increase in PTH concentration was similar to magnitude of the EDTA-induced increase.

Conclusions and Clinical Relevance
Results suggest that the increase in plasma PTH concentration in horses after exercise is secondary to hypocalcemia and that the increase in PTH concentration seems to be commensurate with the decrease in Ca2+ concentration. (Am J Vet Res 1998;59:1605-1607)
Effects of 6α-methylprednisolone acetate on an equine osteochondral fragment exercise model
Authors: Frisbie D. D. , Kawcak C. E. , Baxter G. M. , Trotter G. W. , Powers B. E. , Lassen E. D. , McIlwraith C. W. 
Published: January 2024

Abstract

Objective
To determine effects of intra-articularly administered 6α-methylprednisolone acetate (MPA) in exercised horses with carpal osteochondral fragmentation.

Animals
18 horses: 3 groups of 6 each.

Procedure
An osteochondral (chip) fragment was created in 1 randomly chosen middle carpal joint of each horse. Polyionic fluid (PF) was injected into both middle carpal joints of horses in the control group. In horses of the MPA-control group, MPA was injected into the middle carpal joint without an osteochondral fragment; a similar volume of PF was injected into the contralateral middle carpal joint. In the MPA-treated group of horses, 100 mg of MPA was injected into the middle carpal joint containing the osteochondral fragment; a similar volume of PF was injected into the contralateral joint. Injections were administered on postsurgical days 14 and 28, and horses were exercised on a high-speed treadmill for 8 weeks, starting on postsurgical day 15.

Results
Clinical improvement in degree of lameness was not associated with MPA administration. Joints that contained an osteochondral fragment and were treated with MPA had lower prostaglandin E2 concentration in synovial fluid, and lower scores for intimal hyperplasia and vascularity in synovial membrane, compared with PF-treated joints. However, articular cartilage erosion and morphologic lesions suggested possible deleterious effect of intra-articular MPA administration.

Conclusions
Some beneficial effects of MPA administration on synovial fluid and synovial membrane were identified; however, the deleterious findings contrast with those associated with triamcinolone acetonide used in a similar model, but agree with other results of MPA administration in normal and abnormal joints. (Am J Vet Res 1998;59:1619-1628)
Forelimb joint moments and power during the walking stance phase of horses
Authors: Colborne G. Robert , Lanovaz Joel L. , Sprigings Eric J. , Schamhardt H. C. , Clayton Hilary M. 
Published: January 2024

Abstract

Objective
To calculate normative joint moments of force and power for the forelimb of walking horses as a benchmark against which to compare these mechanical variables in horses with specific lameness.

Animals
4 Dutch Warmblood horses with no recent history of lameness.

Procedure
Horses were walked by hand through the test area, and data from 5 walking trials were collected for each horse. Two camera views were combined with vertical and craniocaudal ground reaction forces to calculate net moments of force in the sagittal plane across the carpal, metacarpophalangeal (fetlock), and distal interphalangeal (coffin) joints during the stance phase of the forelimb. Mechanical power was calculated as the product of net joint moment and the joint's angular velocity.

Results
During the early part of the stance phase, the carpal joint had oscillating periods of energy generation and absorption against a predominant flexor moment, then an absorption phase at the end of the stance phase, as the carpus flexed into swing against an extensor moment. The fetlock absorbed energy in the early part of the stance phase, then the terminal part was marked by a large generation of energy across the joint. A flexor moment was measured at the coffin joint throughout the stance phase, and this coincided with a long phase of energy absorption followed by a short phase of generation for push-off.

Conclusion
Consistency of the power data indicates that typical profiles of work exist for each of the joints (carpus, fetlock, and coffin).

Clinical Relevance
Detection of changes to these profiles of work may contribute to diagnosis of specific lameness conditions.(Am J Vet Res 1998;59:609–614)
Construction and characterization of a glycoprotein E gene-deleted bovine herpesvirus type 1 recombinant
Authors: Chowdhury Shafiqul I. , Ross Carolyn S. D. , Lee Bong J. , Hall Vickie , Chu Hsien-Jue 
Published: January 2024

Abstract

Objective
To construct and characterize a recombinant glycoprotein (g)E gene-deleted bovine herpesvirus (BHV) type 1 (BHV-1).

Procedure
The BHV-1 gE gene-coding region and the flanking upstream and downstream sequences were cloned. The aforementioned cloned DNA was digested with suitable enzymes to release the amino terminal two thirds of that region, and was ligated to the β-galactosidase (β-gal) gene. The resulting plasmid DNA was cotransfected with DNA from full-length, wild-type (WT), BHV-1 Cooper strain of the virus. Recombinant viruses expressing β-gal (blue plaques) were plaque purified and assayed further by blot hybridization for genetic characterization and by immunoblotting for reactivity against BHV-1 gE peptide-specific rabbit polyclonal antibody. One recombinant virus, gEΔ3.1IBR, was characterized in vitro and in vivo. The ability of the recombinant virus to induce BHV-1 neutralizing antibodies in infected calves was investigated by plaque-reduction tests.

Results and Conclusions
The gEΔ3.1IBR virus contained a deletion in the viral gE gene-coding sequences where a stable chimeric reporter (β-gal) gene was inserted. One-step growth kinetics and virus yield of the recombinant and parent viruses were similar, but early after infection, the recombinant virus yield was comparatively less. After intranasal inoculation, the recombinant gEΔ3.1IBR virus replicated in the upper respiratory tract of calves, but the amount of progeny viruses produced was hundredsfold reduced, and duration of virus shedding was shorter. Results of in vivo calf experiments and serum neutralization tests indicated that deleting the gE gene has little effect on inducing neutralizing antibodies against BHV-1, but is sufficient to reduce BHV-1 virulence in calves. (Am J Vet Res 1999; 60:227-232)
Evaluation of activity of selected ophthalmic antimicrobial agents in combination against common ocular microorganisms
Authors: Hinkle Karin M. , Gerding Paul A. , Kakoma Ibulaimu , Schaeffer David J. 
Published: January 2024

Abstract

Objective
To determine in vitro efficacy of gentamicin, tobramycin, and miconazole when used in combination, with or without atropine, against Pseudomonas or Aspergillus sp.

Procedure
Selected ophthalmic agents were combined for predetermined times. Sterile disks impregnated with the combined solutions were prepared and placed on Mueller-Hinton plates that were seeded with Pseudomonas or Aspergillus sp. Zones of growth inhibition were measured at postincubation hours 24 and 48.

Results
Tobramycin alone inhibited growth of Pseudomonas sp, whereas miconazole inhibited growth of Aspergillus sp. Significant differences in zones of growth inhibition when atropine was combined with tobramycin, when gentamicin was combined with miconazole, or when atropine was combined with miconazole and gentamicin, were not detected.

Clinical Relevance
Combining selected ophthalmic therapeutic agents for as long as 6 hours does not appear to alter the in vitro efficacy of the agents against microorganisms used in this study. (Am J Vet Res 1999;60:316–318)
Influence of site and age on biochemical characteristics of the collagen network of equine articular cartilage
Authors: Brama Pieter A. J. , TeKoppele Johan M. , Bank Ruud A. , van Weeren P. René , Barneveld Albert 
Published: January 2024

Abstract

Objective
To determine variations in biochemical characteristics of equine articular cartilage in relation to age and the degree of predisposition for osteochondral disease at a specific site.

Sample Population
Articular cartilage specimens from 53 horses 4 to 30 years old.

Procedure
Healthy specimens were obtained from 2 locations on the proximal articular surface of the first phalanx that had different disease prevalences (site 1 at the mediodorsal margin and site 2 at the center of the medial cavity). Water, total collagen, and hydroxylysine contents and enzymatic (hydroxylysylpyridinoline [HP]) and nonenzymatic (pentosidine) crosslinking were determined at both sites. Differences between sites were analyzed by ANOVA (factors, site, and age), and age correlation was tested by Pearson’s product-moment correlation analysis. Significance was set at P < 0.01.

Results
Correlation with age was not found for water, collagen, hydroxylysine contents, and enzymatic crosslinking. Nonenzymatic crosslinking was higher in older horses and was linearly related to age (r = 0.94). Water and collagen contents and HP and pentosidine crosslinks were significantly higher at site 1. Hydroxylysine content was significantly lower at site 1.

Conclusions
Except for nonenzymatic glycation, the composition of articular cartilage collagen does not change significantly in adult horses. A significant topographic variation exists in biochemical characteristics of the articular cartilage collagen network in equine metacarpophalangeal joints. These differences may influence local biomechanical properties and, hence, susceptibility to osteochondral disease, as will greater pentosidine crosslinks in older horses that are likely to cause stiffer and more brittle cartilage. (Am J Vet Res 1999;60:341-345)
Effects of extrathoracic airway obstruction on intrathoracic pressure and pulmonary artery pressure in exercising horses
Authors: Hackett Richard P. , Ducharme Norm G. , Ainsworth Dorothy M. , Erickson Bruce K. , Erb Hollis N. , Soderholm Leo V. , Thorson Lisa M. 
Published: January 2024

Abstract

Objective
To determine whether dorsal displacesment of the soft palate (DDSP) results in pulmonary artery hypertension and leads to increases in transmural pulmonary artery pressure (TPAP); to determine whether pulmonary hypertension can be prevented by prior administration of furosemide; and to determine whether tracheostomy reduces pulmonary hypertension.

Animals
7 healthy horses.

Procedure
Horses were subjected to 3 conditions (control conditions, conditions after induction of DDSP, and conditions after tracheostomy). Horses were evaluated during exercise after being given saline (0.9% NaCI) solution or furosemide.

Results
Controlling for drug, horse, and speed of treadmill, DDSP-induced increase in intrathoracic pressure was associated with a significant increase in minimum (36 mm Hg), mean (82 mm Hg), and maximum (141 mm Hg) pulmonary artery pressure, compared with values for control horses (30, 75, and 132 mm Hg, respectively). Increases in pulmonary artery pressure did not induce concomitant increases in TPAP. Tracheostomy led to a significant reduction of minimum (53 mm Hg), and mean (79 mm Hg) TPAP pressure, compared with values for control horses (56 and 83 mm Hg, respectively). When adjusted for horse, speed of treadmill, and type of obstruction, all aspects of the pulmonary artery and TPAP curves were significantly decreased after administration of furosemide, compared with those for horses given saline (0.9% NaCI) solution.

Conclusions
DDSP was associated with increases in pulmonary artery pressure but not with increases in TPAP.

Clinical Relevance
Expiratory obstructions such as DDSP are likely to result in pulmonary hypertension during strenuous exercise, but may not have a role in the pathogenesis of exercise-induced pulmonary hemorrhage. (Am J Vet Res 1999;60:485-494).
Alveolar clearance in horses with chronic obstructive pulmonary disease
Authors: Votion Dominique M. , Vandenput Sandrina N. , Duvivier Dominique H. , Lambert Philippe , van Erck Emmanuelle , Art Tatiana , Lekeux Pierre M. 
Published: January 2024

Abstract

Objective
To assess sensitivity of scintigraphic alveolar clearance rate as an indicator of alveolar epithelium damage in horses.

Animals
5 healthy horses (group A) and 5 with chronic obstructive pulmonary disease (COPD; group B).

Procedure
Horses underwent clearance rate (k [%/min]) determination. Clearance rate of group-B horses was determined after remission of the disease following 2 months at pasture (remission 1), stabling in a controlled environment (remission 2), and during crisis induced by exposure to moldy hay and straw. Methacholine challenge test was performed at each investigation period to determine nonspecific pulmonary airway hyperresponsiveness. Pulmonary function tests (PFT) also were performed, and cell populations in bronchoalveolar lavage (BAL) fluid were determined on another occasion.

Results
Group-B horses had significantly faster mean clearance rate during crisis (k = 4.30 ± 0.95%/min), compared with that for remission 1 (k = 1.98 ± 0.55%/min), which did not differ from the rate in group-A horses (k = 1.95 ± 0.33%/min). Despite lack of clinical signs of COPD during remission when stabled in a controlled environment, an intermediate value was found (k = 3.20 ± 0.72%/min).

Conclusions
This technique allowed grading of lung damage induced by COPD, whereas use of PFT and determination of BAL fluid cell populations failed to differentiate between remission 1 and remission 2.

Clinical Relevance
Determination of alveolar clearance rate by use of scintigraphy is a sensitive indicator of lung damage. A modified clearance rate was found despite the lack of clinical and functional changes. (Am J Vet Res 1999;60:495-500)
Evaluation of the role of endotoxin and cortisol on modulation of CD18 adhesion receptors in cows with mastitis caused by Escherichia coli
Authors: Roets Eddy , Burvenich Christian , Diez-Fraile Araceli , Noordhuizen-Stassen Elsbeth N. 
Published: January 2024

Abstract

Objective
To determine the effect of mastitis caused by Escherichia coli on expression of CD18 cell surface receptors and to evaluate the involvement and regulation of receptors by lipopolysaccharide (LPS) and cortisol.

Animals
11 clinically normal lactating Holstein-Friesian cows.

Procedure
Binding of CD18 monoclonal antibodies to neutrophils was studied, using flow cytometry, before and after intramammary inoculation of E coli organisms. Effect of LPS and cortisol on expression of adhesion receptors was investigated, using a whole-blood model.

Results
Expression of CD18 adhesion receptors on bovine neutrophils increased 35% by 12 hours after intramammary inoculation of E coli. By 24 hours after inoculation, the number of receptors had returned to control values. High cortisol concentrations (100 nmol/L) were seen 12 to 18 hours after inoculation. Addition of LPS to blood induced a 30% increase in the number of CD18 receptors, and maximal number of receptors was expressed at an LPS concentration of 0.1 ng/ml. A decrease in the number of CD18 receptors was induced by incubation with cortisol or dexamethasone before challenge-exposure with LPS.

Conclusions
An increase in the number of CD18 receptors on neutrophils is mediated by local production of LPS. Subsequent endogenous release of cortisol may prevent additional increases in the number of receptors.

Clinical Relevance
During acute mastitis caused by E coli, there is an increase in the number of CD18 receptors on circulating neutrophils. Cortisol induces a decrease in the number of CD18 receptors, probably modulating the acute inflammatory response in mammary glands of lactating cows. (Am J Vet Res 1999;60:534–540)
Longitudinal study of lymphocyte subsets and major histocompatibility complex-class II expressing cells in mammary glands of sows
Authors: Magnusson Ulf 
Published: January 2024

Abstract

Objective
To determine whether there is variation attributable to reproductive stage in lymphocyte subsets and major histocompatibility complex (MHC) class II expressing cells in mammary glands of sows.

Animals
8 healthy primiparous crossbred sows that had been nursing piglets for 30 to 35 days.

Procedure
Needle biopsy of the mammary gland was performed after parturition, at midlactation, and after weaning. Various lymphocyte subsets and MHC class II expressing cells were detected immunohistochemically, using monoclonal antibodies.

Results
The number of CD8+ cells was significantly lower after parturition than after weaning but not significantly lower than at midlactation. The number of IgA-bearing cells was lower after parturition and after weaning than at midlactation. There were more B cells at midlactation than after weaning. There was no change over time in the number of CD4+ cells or MHC class II expressing cells. Immunohistochemically positive cells were detected only in interalveolar tissue.

Conclusions and Clinical Relevance
Certain lymphocyte subsets in mammary glands of sows are affected by reproductive stage. The data do not support the hypothesis that development of postparturient coliform mastitis may be the result of impaired mammary immune defenses at parturition. (Am J Vet Res 1999;60:546–548)
Distribution and environmental risk factors for paratuberculosis in dairy cattle herds in Michigan
Authors: Johnson-Ifearulundu Yvette , Kaneene John B. 
Published: January 2024

Abstract

Objective
To determine prevalence of paratuberculosis among dairy cattle herds and to identify associated soil-related risk factors.

Sample Population
Serum and soil samples for 121 Michigan dairy herds.

Procedure
Blood samples were collected from cows at each farm and tested for Mycobacterium paratuberculosis, using an antibody ELISA. Soil samples were collected from pastures and exercise lots; pH and available iron content were determined. A questionnaire was administered to collect data regarding farm management practices and productivity.

Results
55% of the herds tested had ≥ 2 M paratuberculosis-positive cattle. Adjusting sample prevalence for distribution of herd size strata yielded a statewide herd prevalence of 54%. Of 3,886 cattle tested, 267 had positive results. Prevalence of test-positive cattle was 6.9%. For every part per million (ppm) increase in soil iron content, there was a 1.4% increase in the risk of a herd being test-positive. An increase in soil pH of 0.1 was associated with a 5% decrease and an increase in soil iron content of 10 ppm was associated with a 4% increase in the number of test-positive cattle. Application of lime to pasture areas was associated with a herd being only 10% as likely to be paratuberculosis positive and with a 72% reduction in number of test-positive cattle.

Conclusions and Clinical Relevance
Prevalence of paratuberculosis-positive dairy herds in Michigan (54%) was greater than expected, but prevalence of paratuberculosis-positive cattle (6.9%) was within anticipated values. These prevalences were associated positively with acidic soil and increased soil iron content. Application of lime to pasture areas was associated with reduced risk of paratuberculosis. (Am J Vet Res 1999;60:589–596)
Health and growth performance of barrows reared in all-in/all-out or continuous flow facilities with or without a chlortetracycline feed additive
Authors: Ice A. D. , Grant A. L. , Clark L. K. , Cline T. R. , Einstein M. E. , Martin T. G. , Diekman M. A. 
Published: January 2024

Abstract

Objective
To compare health and growth peformance in barrows reared in all-in/all-out (AIAO) or continuous flow (CF) management systems.

Animals
400 barrows.

Procedure
Barrows (approx 2 months old) were allotted to 4 replications (100 barrows each); barrows were housed in AIAO or CF rooms (10 pens/room), and 50 pigs/replicate received chlortetracycline (CTC, 110 mg/kg of feed). Barrows from each pen were slaughtered at 3, 4, 5, and 6 months old.

Results
Barrows in the AIAO room had greater total daily gain (TDG) and lean daily gain (LDG) than did barrows in the CF room. Addition of CTC did not improve TDG or LDG in either environment. Barrows in the AIAO room reached body weight of 104.5 kg in 169.7 days, compared with 177.3 days for barrows in the CF room. Feed-to-gain ratio was not affected by management or CTC. Lungs from barrows reared in AIAO facilities had a lower percentage of lesions than did lungs of barrows reared in CF facilities (1.74% vs 9.52%). Addition of CTC did not affect prevalence and extent of lung lesions. Extent of lung lesions was positively correlated with change in serum optical density (OD) to Mycoplasma hyopneumoniae (r = 0.35), but not with change in serum OD to Actinobacillus pleuropneumoniae. Lean growth and serum OD to M hyopneumoniae and A pleuropneumoniae were not correlated.

Conclusions
Health and growth performance were better for barrows in an AIAO facility, compared with a CF facility, but addition of CTC to feed failed to enhance health or performance of barrows in either facility. (Am J Vet Res 1999;60:603–608).