bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epidemiological characteristics of bovine clinical mastitis caused by Staphylococcus aureus and Escherichia coli studied by DNA fingerprinting
Authors: Lam T. J. G. M. , Lipman L. J. A. , Schukken Y. H. , Gaastra W. , Brand A. 
Published: January 2024

Abstract

Objective
To study the epidemiology of clinical mastitis caused by Escherichia coli and Staphylococcus aureus by differentiating isolates with DNA fingerprinting techniques, using polymerase chain reaction.

Design
Milk samples were collected from cases of clinical mastitis in dairy cows. Escherichia coli and S aureus isolates from these cases were compared within and between cows and herds.

Sample Population
Seven dairy herds with an average bulk milk somatic cell count < 150,000/ml, and incidence of cows with clinical mastitis of > 25%/y.

Procedure
Chromosomal DNA was isolated from E coli and S aureus strains isolated from cases of clinical mastitis, and amplified by polymerase chain reaction, using enterobacterial repetitive intergenic consensus primers for E coli and a random amplified polymorphic DNA primer for S aureus. Escherichia coli and S aureus strains were identified and differentiated, using their DNA polymorphism pattern.

Results
Multiple E coli genotypes were found in each of the herds. Persistent infections with E coli were sporadic. Only a limited number of different S aureus genotypes was found in each of the herds studied. Recurrent cases of S aureus mastitis were found in 25% of quarters with clinical S aureus mastitis. Comparing S aureus isolates from different herds indicated that 1 S aureus genotype was most prevalent.

Conclusions
Because different quarters were infected with different genotypes, it was concluded that E coli is an environmental pathogen, and does not generally spread from quarter to quarter. The hypothesis that S aureus mastitis is a contagious disease, spreading from infected to uninfected quarters, could not be rejected. (Am J Vet Res 1996;57:39-42)
Transmission of two pseudorabies virus strains that differ in virulence and virus excretion in groups of vaccinated pigs
Authors: Bouma A. , De Jong M. C. M. , Kimman T. G. 
Published: January 2024

Abstract

Objective
To determine whether 2 Pseudorabies virus (PRV) strains that differ in virulence differ in transmission among vaccine strain 783-inoculated pigs.

Design
Three experiments were conducted, each with 2 groups of 10 pigs inoculated with the glycoprotein E-negative vaccine 783. In the first 2 experiments, half of one group was inoculated with the mildly virulent strain Sterksel, and half of the other group was inoculated with the virulent strain NIA-3. The remaining pigs were contact-exposed to the inoculated pigs. In the third experiment, 2 pigs in each group were inoculated with strain NIA-3, and the other 8 pigs in each group were contact-exposed to these 2 pigs.

Animals
Specific-pathogen-free pigs that were seronegative for antibodies to PRV.

Procedure
Estimation of the transmission of virus in each group was based on a stochastic model, in which the observable variable was the number of contact infections. The sole parameter of the model was the reproduction ratio θ. A glycoprotein E ELISA was used to determine whether infection occurred. Virus excretion in the oropharyngeal fluid was determined by plaque assay to measure infectivity.

Results
Vaccinated pigs had a significant difference in virus excretion between the mildly virulent and virulent strains. Sterksel strain-inoculated pigs shed significantly more virus than did NIA-3 strain-inoculated pigs. Despite this difference in virus excretion, the 2 strains did not differ in transmission.

Conclusions
Both PRV strains would be eliminated from a population of vaccine strain 783-inoculated pigs. (Am J Vet Res 1996;57:43-47)
Distribution and appearance of elastic fibers in the dermis of clinically normal dogs and dogs with solar dermatitis and other dermatoses
Authors: Frank Linda A. , Calderwood-Mays Maron B. , Kunkle Gail A. 
Published: January 2024

Abstract

Objective
To determine the distribution and amount of elastic fibers in the dermis of clinically normal dogs and dogs with dermatoses, particularly solar dermatitis.

Design
Skin specimens from 7 anatomic sites were obtained from 19 clinically normal dogs after euthanasia to evaluate the normal distribution o elastic fibers. Biopsy specimens also were obtained from 34 dogs with dermatoses, including 16 with solar dermatitis. Tissue sections were stained with H&E, Verhoeff-van Gieson, and periodic acid-Schiff.

Animals
19 clinically normal dogs and 34 dogs with dermatoses.

Procedure
Numbers of elastic fibers were graded subjectively. Comparisons between clinically normal dogs and dogs with dermatoses were made.

Results
Normal elastic fibers were present in low numbers in the dermis of adult dogs, regardless of anatomic site or presence or severity of dermatitis. Condensed elastotic material was visualized in only 2 dogs with solar dermatitis. In both dogs, the elastotic material was Verhoeff-van Gieson and periodic acid-Schiff stain positive but was not visible with H&E stain. The most frequent histopathologic finding in the dermis of dogs with solar dermatitis was superficial dermal fibrosis.

Conclusions
The dermis of clinically normal dogs does not contain abundant elastic fibers. Alterations of elastic fibers in dogs with solar dermatitis are rare. Superficial dermal fibrosis may be a better indicator of solar damage.
Analgesic, hemodynamic, and respiratory effects of caudal epidurally administered xylazine hydrochloride solution in mares
Authors: Skarda Roman T. , Muir William W. 
Published: January 2024

Abstract

Objective
To examine effects of 0.25 mg of xylazine/kg of body weight diluted to a total volume of 6 ml/450 kg with sterile 0.9% NaCl, administered into the epidural space of the sacrococcygeal joint on perineal analgesia, sedation, ataxia, and respiratory and cardiovascular function in standing mares:

Design
Randomized, blinded study, using xylazine (treatment) and 0.9% NaCl (controls). At least 2 weeks elapsed between the treatments.

Animals
Eight healthy mares.

Procedure
Blood samples were drawn. Systemic hemodynamics were determined, including cardiac output and pulmonary arterial, systemic arterial, and right atrial pressures. Two-way ANOVA with repeated measures was used to detect significant (P < 0.05) differences between mean scores of analgesia, sedation, ataxia, and cardiorespiratory variables before and during a 3-hour testing period. Analgesia was determined by lack of sensory perception to electrical stimulation at the perineal dermatome and no response to needle prick stimulation extending from coccyx to S3 dermatomes. Sedation was determined by head ptosis.

Results
Epidurally administered xylazine induced variable bilateral caudal analgesia extending from coccyx to S3, with minimal sedation, ataxia, and cardiovascular and respiratory depression in standing mares. Analgesia was attained at 15 ± 6 minutes and lasted for 165 to over 180 minutes. Heart and respiratory rates, systolic, diastolic, and mean arterial blood pressure, PCV, hemoglobin concentration, arterial oxygen content, and oxygen transport were decreased after xylazine, but not 0.9% NaCl, treatment. Cardiac output, stroke volume, mean right atrial pressure, mean pulmonary artery pressure, systemic vascular resistance, pulmonary vascular resistance, arterial and mixed venous pH and gas tensions (Po2 and Pco2), oxygen consumption, blood temperature, and rectal temperature did not change significantly (P < 0.05) after epidural administration of xylazine or 0.9% NaCl.

Conclusions
Caudal epidurally administered xylazine (0.25 mg/kg in 6 ml of 0.9% NaCl) can be given safely to induce prolonged (> 2 hours) caudal analgesia with minimal sedation, ataxia, and circulatory and respiratory disturbances in conscious, standing mares.
Effects of inhalation anesthetic agents on response of horses to three hours of hypoxemia
Authors: Whitehair Karen J. , Steffey Eugene P. , Woliner Michael J. , Willits Neil H. 
Published: January 2024

Abstract

Objective
To study the effects of inhalation anesthetic agents on the response of horses to 3 hours of hypoxemia.

Design
Controlled crossover study.

Animals
Five healthy adult horses.

Procedure
Horses were anesthetized twice: once with halothane, and once with isoflurane in O2. Anesthetized horses were positioned in left lateral recumbency. Constant conditions for the study began at 2 hours of anesthesia. A constant agent dose of 1.2 minimum alveolar concentration, PaO2 of 50 ± 5 mm of Hg, and PaCO2 of 45 ± 5 mm of Hg were maintained for 3 hours. Circulatory measurements were made at 0.5, 1, 2, and 3 hours of hypoxemia (anesthesia hours 2.5, 3, 4, and 5). Blood was collected from horses for biochemical analyses before anesthesia, within a few minutes after standing, and at 1, 2, 4, and 7 days after anesthesia.

Results
Cardiac index was greater (P = 0.018) during isoflurane than halothane anesthesia. Cardiac index remained constant during the 3 hours of hypoxemia during halothane anesthesia, whereas it decreased from the baseline during isoflurane anesthesia. Marginally nonsignificant P values for an agent difference were detected for arterial O2 content (P = 0.051), and oxygen delivery (P = 0.057). Serum activities of aspartate transaminase (P = 0.050) and sorbitol dehydrogenase (P = 0.017) were higher in halothane-anesthetized horses than in isoflurane-anesthetized horses. Circulatory function was better in hypoxemic horses anesthetized with isoflurane than with halothane. Isoflurane resulted in less muscular injury in hypoxemia horses than did halothane anesthesia. Halothane anesthesia and hypoxemia were associated with hepatic insult.

Conclusion
Isoflurane is better than halothane for hypoxemic horses.(Am J Vet Res 1996;57:351-360)
Effects of vitamin E on mammary and blood leukocyte function, with emphasis on Chemotaxis, in periparturient dairy cows
Authors: Politis I. , Hidiroglou N. , White J. H. , Gilmore J. A. , Williams S. N. , Scherf H. , Frigg M. 
Published: January 2024

Abstract

Objective
To determine the effect of vitamin E supplementation on the immune system of dairy cows.

Design
The following immune parameters were followed: production of chemotactic factors and superoxide by mammary macrophages and chemotactic responsiveness of blood neutrophils.

Animals
16 healthy Holstein dairy cows.

Procedure
Dairy cows were assigned to 1 of 2 experimental groups: control (no vitamin E supplementation) and vitamin E supplemented. Supplementation of vitamin E started 4 weeks before and continued up to 8 weeks after parturition, and included oral supplementation of vitamin E at the rate of 3,000 IU/cow/d. In addition, the same group of cows received 1 injection of vitamin E (5,000 IU) 1 week prior to the expected date of parturition. Blood samples were collected weekly throughout the experimental period.

Results
Vitamin E supplementation enhanced by 30 to 83% (P < 0.05) chemotactic responsiveness of blood neutrophils beginning 2 weeks before to 4 weeks after parturition, compared with controls. There were no differences in production of superoxide or chemotactic factors by mammary macrophages between control and vitamin E-supplemented cows.

Conclusions
Vitamin E supplementation prevents the periparturient inhibition of neutrophil Chemotaxis. It is unlikely that vitamin E affects directly the function of mammary macrophages. (Am J Vet Res 1996;57:468–471)
Disposition and excretion of 6-methoxy-2-naphthylacetic acid, the active metabolite of nabumetone in horses
Authors: Soma L. R. , Uboh C. E. , Rudy J. A. , Smith M. S. 
Published: January 2024

Abstract

Objective
To examine, in horses, the disposition and excretion of the active metabolite 6-methoxy-2-naphthylacetic acid (6MNA) of the nonsteroidal anti-inflammatory prodrug nabumetone.

Design
Pharmacokinetic analysis of 6MNA after oral administration of nabumetone and IV administration of 6MNA.

Procedure
Using a crossover design, 5 horses were orally administered 3.7 mg of nabumetone/kg of body weight. After a 3-week washout period, 4 horses were administered 2.5 mg of 6MNA/kg, IV.

Results
Absorption of nabumetone from the gastrointestinal tract and its metabolism to 6MNA had a median appearance half-life of 0.88 hour. The elimination half-life was 11 hours. Area under the plasma concentration time curve for 6MNA after oral administration of nabumetone was 120.6 mg/h/L. A dose of 2.5 mg/kg of 6MNA administered IV resulted in plasma concentration nearly equivalent to that induced by the orally administered dose. Disposition of 6MNA was modeled as a one-compartment, first-order elimination. The area under the plasma concentration time curve for IV administration of 6MNA was 117.0 mg/h/L, and the specific volume of distribution was 0.247 L/kg. The distribution half-life and the elimination half-life were 0.56 and 7.90 hours, respectively. Percentage of total dose recovered in urine for the 36-hour collection period after the oral and IV administrations was 7.4 and 5.3%, respectively.

Conclusions
Metabolism of nabumetone to 6MNA, as reported in other species, also occurs in horses. There were a number of additional metabolites of nabumetone in urine that could not be fully identified and characterized. (Am J Vet Res 1996;57:517–521)
Inhibition of the protease activity in tracheobronchial aspirates of horses with chronic obstructive pulmonary disease
Authors: Koivunen Anna-Liisa , Maisi Päivi , Fang Weihuan , Sandholm Markus 
Published: January 2024

Abstract

Objectives
To clarify the role of proteolytic enzymes in the pathogenesis of chronic obstructive pulmonary disease (COPD) in horses, and to investigate new possibilities for treatment of this disease by interfering in the proteolytic process.

Design
Effect of antiproteolytic activity of selected protease inhibitors on tracheal aspirates was studied in vitro, and the inhibition profiles were compared with those of purified proteases.

Sample Population
Respiratory tract secretions with antiproteolytic activity from 9 horses with COPD.

Procedure
Caseinolytic agar-diffusion assay.

Results
The protease-inhibition profile of tracheal aspirates differed from horse to horse. The profiles did not resemble that of any of the pure proteases. Acetylcysteine, pentamidine, and diminazene were most effective in inhibiting proteolytic activity in tracheal aspirates in vitro.

Conclusions
A mixed type of proteolytic activity is present in the respiratory tract secretions of horses with COPD.

Clinical Relevance
Acetylcysteine, pentamidine, and diminazene seem to have potential to be used in vivo to protect the lungs of horses with COPD from proteolytic damage. (Am J Vet Res 1996; 57:603–607)
Comparison of hematologic reference intervals between culture system and type of hybrid striped bass
Authors: Hrubec Terry C. , Smith Stephen A. , Robertson John L. , Feldman Bernard , Veit Hugo P. , Libey George , Tinker Mary Kay 
Published: January 2024

Abstract

Objective
To determine and compare hematologic reference intervals for hybrid striped bass from different culture systems and for 2 types of hybrid.

Design
Observational comparison study.

Animals
Clinically normal sunshine bass (reciprocal hybrid striped bass, female Morone chrysops × male M saxatilis) raised in high-density recirculating systems, sunshine bass raised in tanks with biofilters, and palmetto bass (original hybrid striped bass, female M saxatilis × male M chrysops) raised in tanks with biofilters.

Procedure
Hematologic reference intervals were determined for fish from the different production systems, following the National Committee for Clinical Laboratory Standards guidelines. Reference intervals from the 3 groups were compared.

Results
Reference intervals were significantly different between sunshine bass in the 2 culture systems and between sunshine and palmetto bass. Many of the differences were slight, but notable differences were observed. Sunshine bass in recirculating systems had higher total leukocyte, lymphocyte, neutrophil, and monocyte counts than did either hybrid in tanks. Palmetto bass had a greater number of neutrophils than monocytes, whereas sunshine bass had more monocytes than neutrophils. Additionally, palmetto bass had a lower PCV and hemoglobin value than did either group of sunshine bass.

Conclusions
Separate reference intervals should be developed for hybrid striped bass in different culture systems and for different types of hybrids.

Clinical Relevance
Determining reference intervals for hybrid striped bass provides a tool to assess the health status of these fish. (Am J Vet Res 1996; 57:618–623)
Blood biochemical reference intervals for sunshine bass (Morone chrysops × Morone saxatilis) in three culture systems
Authors: Hrubec Terry C. , Smith Stephen A. , Robertson John L. , Feldman Bernard , Veit Hugo P. , Libey George , Tinker Mary Kay 
Published: January 2024

Abstract

Objective
To determine and compare biochemical reference intervals for sunshine bass (hybrid striped bass) from 3 culture systems.

Design
Observational comparison study.

Animals
Clinically normal sunshine bass (reciprocal hybrid striped bass, female Morone chrysops × male M saxatilis) raised in high-density recirculating systems (80 g/L), low-density tanks (5 g/L) with biofilters, and cages (70 g/L) in a fresh water pond.

Procedure
Biochemical reference intervals were determined for fish from the different production systems following the National Committee for Clinical Laboratory Standards guidelines. Reference intervals from the 3 groups were compared.

Results
Reference intervals were significantly different between sunshine bass in the various culture systems. Though most of the differences in reference intervals were minor, fish in the high-density recirculating system had higher concentrations of total protein, albumin, globulin, creatinine, and phosphorus, and lower chloride values. There were no significant differences in glucose concentrations among the 3 groups of fish, and no differences in cortisol concentrations between fish in tanks and cages.

Conclusions
Separate reference intervals should be developed for hybrid striped bass in different culture systems.

Clinical Relevance
Determining biochemical reference intervals for hybrid striped bass provides a tool to assess the health status of these fish. (Am J Vet Res 1996; 57:624–627)
Pharmacokinetic model for cefazolin distribution during total hip arthroplasty in dogs
Authors: Marcellin-Little Denis J. , Papich Mark G. , Richardson Daniel C. , DeYoung David J. 
Published: January 2024

Abstract

Objectives
To compare cefazolin pharmacokinetics in serum and concentrations in tissues during total hip arthroplasty in dogs with and without hip dysplasia, and to calculate the optimal dosage of cefazolin for prophylactic use during total hip arthroplasty.

Animals
10 dogs with hip dysplasia and 3 clinically normal dogs.

Procedure
Blood samples and tissue specimens from the coxofemoral joint capsule, acetabulum, and femur were obtained during unilateral total hip arthroplasty. Cefazolin concentrations in serum and tissue specimen supernatant were determined, using high-performance liquid chromatography, for use in pharmacokinetic analysis. Mathematical simulation of serum cefazolin concentrations was used to to predict the optimal dose.

Results
Mean pharmacokinetic constants (SEM) were 0.146 (0.013) mm-1 for α, 4.74 min for t1/2α,, 0.015 (0.004) min-1 for ß, and 46.83 min for t1/2ß. Significant difference was not detected for cefazolin distribution and elimination between dogs with and without hip dysplasia. Additionally, significant difference was not observed in pharmacokinetic parameters describing distribution and elimination between the first and second doses of cefazolin. The predicted optimal dosage regimen was 8 mg/ kg of body weight, IV, every hour or 22 mg/kg, IV, every 2 hours.

Clinical Relevance
For prophylactic IV treatment during total hip arthroplasty, use of cefazolin at a dosage of 8 mg/kg every hour or 22 mg/kg every 2 hours should maintain serum cefazolin concentrations at least 10× the minimum inhibitory concentration for 3 to 4 hours. (Am J Vet Res 1996; 57:720–723)
Hemodynamic effects of medetomidine-midazolam-butorphanol and medetomidine-midazolam-buprenorphine combinations and reversibility by atipamezole in dogs
Authors: Pypendop Bruno , Serteyn Didier , Verstegen John 
Published: January 2024

Abstract

Objective
To characterize the hemodynamic effects of medetomidine (1 mg/m2 of body surface area; dosage, 39 to 46 μg/kg of body weight, IM) and midazolam (1 mg/kg of body weight, IV) combined with butorphanol (0.1 mg/ kg, IV), buprenorphine (10 μg/kg, IV), or saline solution. Reversibility of these effects by atipamezole (2.5 mg/m2; dosage, 97.5 to 115 μg/kg, IM) was evaluated.

Design
2 treated groups and 1 control group, without repetition.

Animals
15 clinically normal dogs (3 groups of 5).

Procedure
Medetomidine was administered at time 0; midazolam and butorphanol, buprenorphine, or saline solution at time 20; and atipamezole at time 60. Heart rate, systemic and pulmonary arterial pressures, central venous pressure, body temperature, cardiac output, and arterial and mixed venous blood gas tensions and pH were measured. Cardiac index, stroke index, systemic and pulmonary vascular resistances, and left and right stroke work indexes were calculated.

Results
Body temperature, heart rate, cardiac index, and stroke index were significantly decreased below baseline values in some groups. Central venous pressure, pulmonary capillary wedge pressure, and systemic vascular resistance were significantly increased above baseline in all groups. Arterial and venous Po2 and pH decreased in all groups and Pco2 increased, but these changes were more pronounced when buprenorphine was administered. Arterial pressure decreased after atipamezole administration.

Conclusions
The combinations seemed to result in cardiorespiratory depressant effects of similar importance and most of these effects, which are related to medetomidine, were reversed by atipamezole. (Am J Vet Res 1996; 57:724–730)