bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of analgesia and cardiorespiratory effects of epidurally administered butorphanol in isoflurane-anesthetized dogs
Authors: Troncy Eric , Cuvelliez Sophie G. , Blais Diane 
Published: January 2024

Abstract

Objective
To determine variations in minimal alveolar concentration (MAC) of isoflurane and analgesic and cardiorespiratory effects of lumbosacral epidural administration of 0.25 mg of butorphanol/kg of body weight in dogs.

Animals
16 healthy male dogs.

Procedure
Dogs were anesthetized with isoflurane alone. Eight dogs received butorphanol (group B) and the others an equal volume of isotonic saline solution (group S) administered by a catheter inserted in the lumbosacral epidural space. Isoflurane MAC was determined before and 30 minutes after the epidural injection, along with noxious stimulation to the fore- and hind limbs. Cardiorespiratory variables were recorded prior to and until 120 minutes after epidural administration. At that time, isoflurane anesthesia was ended, and nociception (toe pinch and pin-prick responses) was evaluated for 7 hours. Dogs were observed for 3 days to determine presence of neurologic side effects.

Results
For group-B dogs, isoflurane MAC decreased by 31 ± 8.6% after butorphanol was administered. Cutaneous insensitivity (to pin-prick nociceptive test) persisted for 3 hours after the end of isoflurane anesthesia in group-B dogs. No response was observed to toe pinch stimulation for 80 minutes after anesthesia.

Conclusions
Epidural administration of 0.25 mg of butorphanol/kg in dogs was safe; minimal cardiorespiratory and no neurologic side effects were observed, and analgesia and an isoflurane-sparing effect were apparent.

Clinical Relevance
The short duration of action of epidurally administered butorphanol limits its value for clinical practice. (Am J Vet Res 1996;57:1478-1482)
Cerebrospinal fluid acid-base status during normocapnia and acute hypercapnia in equine neonates
Authors: Geiser Dennis Richard , Andrews Frank Michael , Rohrbach Barton Wing , Provenza Melanie Kay 
Published: January 2024

Abstract

Objective
To determine normal acid-base status of the CSF and to compare it with changes during acute hypercapnia in equine neonates.

Animals
10 clinically normal foals between 1 and 12 days old.

Procedure
CSF and arterial and venous blood samples were collected every 15 minutes during 45 minutes of normocapnia and 90 minutes of hypercapnia in isoflurane-anesthetized foals. CSF samples were collected via a subarachnoid catheter placed in the atlanto-occipital space.

Results
Comparison of blood and CSF gases during normocapnia indicated that CSF was significantly more acidic than blood. The lower pH was attributable to higher CO2 and lower bicarbonate concentrations than those in blood. During hypercapnia, CSF CO2 increased and pH decreased parallel to changes in blood, but changes were not as great as similar changes in venous blood, indicating that some degree of buffering occurs in the CSF of foals.

Conclusions
Normal CSF acid-base status in equine neonates is similar to that in other domestic species. The blood-brain and blood-CSF interfaces in neonates allow rapid diffusion of CO2, but allow only slow diffusion of bicarbonate. Equine neonates are capable of buffering respiratory-induced acid-base changes in the CSF, but the buffering capacity is less than that of the vascular compartment.

Clinical Relevance
Neonatal foals may develop severe respiratory compromise, resulting in hypoxemia and hypercapnia. Because the ability of the CSF to buffer acid-base changes in neonates is reduced, hypercapnia may contribute to the CNS abnormalities that often develop in sick neonates. Thus, normal blood gas values should be maintained in diseased equine neonates. (Am J Vet Res 1996;57:1483-1487)
Effects of acepromazine maleate and phenoxybenzamine on urethral pressure profiles of anesthetized, healthy, sexually intact male cats
Authors: Marks Steven L. , Straeter-Knowlen Ingrid M. , Moore Michael , Speth Robert , Rishniw Mark , Knowlen Grant G. 
Published: January 2024

Abstract

Objectives
To evaluate the effects of 2 compounds with α-adrenergic antagonist properties on the urethral pressures of anesthetized, healthy, sexually intact male cats, and to evaluate one of the compounds for effect on striated muscle.

Animals
20 healthy, sexually intact male cats.

Procedure
Cats were anesthetized with halothane, and urethral pressure profilometry was performed before and after treatment. 125l-labeled α-bungarotoxin bound to nicotinic receptors of murine skeletal muscle was used in a competitive binding study with acepromazine maleate.

Results
Acepromazine maleate significantly decreased intraurethral pressures in the preprostatic (19%) and pro-static (21%) regions of the urethra. There was no effect on the postprostatic/penile segment. Acepromazine did not inhibit 125l-labeled α-bungarotoxin binding to nicotinic receptors in murine skeletal muscle. Phenoxybenzamine significantly decreased intraurethral pressures (14%) in the preprostatic region of the urethra only.

Conclusions
Acepromazine maleate and phenoxy-benzamine have effects on the smooth muscle of the urethra of healthy, male cats. Acepromazine has no effect on striated muscle.

Clinical Relevance
α-Adrenergic compounds may be used in the pharmacologic management of feline urinary tract disease. (Am J Vet Res 1996;57:1497-1500)
Effects of long-term treatment with enalapril or hydralazine on the renin-angiotensin-aldosterone system and fluid balance in dogs with naturally acquired mitral valve regurgitation
Authors: Haggstrom Jens , Hansson Kerstin , Karlberg Bengt E. , Kvart Clarence , Madej Andrzej , Olsson Kerstin 
Published: January 2024

Abstract

Objective
To study long-term effects of enalapril, an angiotensin-converting enzyme inhibitor, and hydralazine, an arteriodilator, on renin-angiotensin-aldosterone system and fluid balance before and after administration of furosemide.

Animals
22 dogs with clinical signs of congestive heart failure (CHF) attributable to mitral regurgitation.

Procedure
After initial examination, 12 dogs received enalapril and 10 received hydralazine. Dogs were re-examined 3 weeks and 6 months after initial examination. Furosemide was added after the 3-week examination, and at 6 months, dogs had received furosemide for at least 4 months.

Results
Angiotensin II and aldosterone plasma concentrations were low before treatment, and only aldosterone became significantly decreased after enalapril monotherapy. Concentrations of both hormones and heart rate increased in dogs receiving hydralazine monotherapy, and fluid retention was evident. After long-term treatment with either of the 2 drugs together with furosemide, angiotensin II and aldosterone values increased in both groups. Natriuresis and kaliuresis developed in all dogs, with greatest effect in those receiving enalapril and furosemide. These dogs had decreased plasma sodium concentration, whereas potassium concentration was equally decreased in both groups. After 6 months, the enalapril group, but not the hydralazine group, had increased cardiac size. All dogs had moderate reduction of weight and were azotemic, although changes were more pronounced in those of the hydralazine group.

Conclusion
The 2 drugs have different effects on the renin-angiotensin-aldosterone system and fluid balance in dogs with CHF. (Am J Vet Res 1996;57:1645–1652)
Endotoxin stimulates in vitro pituitary growth hormone release in eicosanoid-dependent manner
Authors: Coleman E. S. , Sartin J. L. 
Published: January 2024

Abstract

Objective
To investigate the signal transduction pathways by which endotoxin stimulates in vitro pituitary cell growth hormone (GH) release.

Animals
Pituitary cell cultures derived from 6 sheep.

Procedure
Signal transduction pathways involved in endotoxin-mediated GH release from sheep pituitary cell cultures were evaluated by the use of specific blockers of arachidonic acid and its metabolites, extracellular calcium, protein kinase C, and protein kinase A. Cell cultures were exposed to the specific blockers in the presence or absence of endotoxin (Escherichia coli O55:B5, 10 μg/ml) for 24 hours. In addition, effects of endotoxin on GH cell content and GH mRNA values were determined.

Results
Nordihydroquairetic acid (lipoxygenase blocker, 10 μM, 30 μM) and eicosatetraynoic acid (arachidonic acid competitor, 10 μM) decreased endotoxin-stimulated GH release. The calcium channel blocker verapamil (25 μM) decreased baseline and endotoxin-stimulated GH release. Phorbol myristate acetate-induced down-regulation of protein kinase C, indomethacin, or the protein kinase A blocker H89 did not alter endotoxin-stimulated GH release. Endotoxin increased GH mRNA values by 50.1 ± 6.0%, but the cell content of GH was not affected.

Conclusions
A direct effect of endotoxin on the pituitary gland to stimulate GH secretion was evident, an effect mediated predominantly by arachidonic acid and its metabolites through the lipoxygenase pathway. Endotoxin-stimulated GH release requires extracellular calcium and is associated with increased cell GH mRNA content.

Clinical Relevance
A better understanding of the signal transduction pathways involved in endotoxin-mediated effects will allow more appropriate therapeutic intervention in clinical cases of endotoxemia. (Am J Vet Res 1996;57:1662–1667)
Antibody responses measured by various serologic tests in pigs orally inoculated with low numbers of Toxoplasma gondii oocysts
Authors: Dubey J. P. , Andrews C. D. , Lind P. , Kwok O. C. H. , Thulliez P. , Lunney J. K. 
Published: January 2024

Abstract

Objective
To follow antibody responses measured by various serologic tests in pigs orally inoculated with low (≤ 10 oocysts) numbers of Toxoplasma gondii oocysts.

Animals
24, 2- to 3-month-old pigs.

Procedure
Pigs (n = 42) were inoculated orally with 10 (14 pigs) or 1 (28 pigs) infective oocysts, and 6 pigs served as uninoculated controls. Blood (serum) samples were obtained at 1- to 3-week intervals until euthanasia. At necropsy, the brain, heart, and tongue of pigs were bioassayed in mice and cats for isolation of T gondii. Modified agglutination test (MAT), using whole, fixed tachyzoites and mercaptoethanol; latex agglutination test (LAT); indirect hemagglutination test (IHAT); Sabin-Feldman dye test (DT); and ELISA were used to evaluate serologic responses to T gondii.

Results
T gondii was isolated from tissues of 13 of 14 pigs each fed 10 oocysts, 17 of 28 pigs each fed 1 oocyst, and 0 of 6 control pigs. 29 of 30 T gondii-infected pigs developed antibodies when measured by MAT, DT, and ELISA; the 1 seronegative-infected pig had been fed 10 oocysts and was euthanatized 69 days after inoculation. LAT detected antibodies in 26 of 30 T gondii-infected pigs. IHAT detected antibodies in 11 T gondii-infected pigs.

Conclusion
MAT, DT, and ELISA were more sensitive serologic assays than LAT and IHAT for detecting antibodies induced by low numbers of T gondii in pigs. (Am J Vet Res 1996;57:1733–1737)
Effects of selenium and vitamin E administration during a late stage of pregnancy on colostrum and milk production in dairy cows, and on passive immunity and growth of their offspring
Authors: Lacetera Nicola , Bemabucci Umberto , Ronchi Bruno , Nardone Alessandro 
Published: January 2024

Abstract

Objective
To determine effects of selenium (Se) and vitamin E (VE) administration in late pregnancy on Se status, plasma immunoglobulin concentrations, and colostrum and milk production of dairy cows, and on Se status, passive immunity, and growth of their offspring.

Animals
25 Holstein cows and their offspring.

Procedure
3 and 1.5 weeks before calving, sodium selenite (5 mg/100 kg of body weight) and d, l-α-tocopheryl acetate (25 IU/100 kg) were administered to 13 cows. The other 12 cows were not treated. Se status was assessed by measurement of glutathione peroxidase activity of erythrocytes (GSH-Px-E).

Results
The 13 treated cows had higher (P < 0.01) GSH-Px-E values at calving and during the first 12 weeks of lactation. Changes in plasma immunoglobulin concentrations before or after calving did not differ between the 2 groups of cows. During the first 36 hours after calving (4 milkings), treated cows produced 22% more colostrum than did their nontreated counterparts (P < 0.005). Percentages of colostral immunoglobulins did not differ between the 2 groups. During the first 12 weeks of lactation, treated cows produced 10% more milk than did nontreated cows (P < 0.005). GSH-Px-E values at birth and 28 days of life were significantly higher in calves from treated cows. Plasma immunoglobulin concentrations and body weight during the first 56 days after birth did not differ between calves born to treated or non-treated cows.

Conclusions and Clinical Relevance
Cows given Se and VE in late pregnancy produce large quantities of colostrum and milk. Colostrum produced from cows given Se and VE is suitable to feed newborn calves and to be stored for later use. Improvement of Se status in calves born to cows given Se and VE in late pregnancy is not beneficial to passive immunity and growth. (Am J Vet Res 1996;57:1776–1780)
Isolation and characterization of the canine melanoma antigen recognized by the murine monoclonal antibody IBF9 and its distribution in cultured canine melanoma cell lines
Authors: Oliver J. L. , Wolfe L. G. , Lopez M. K. , Church-Bird A. , Toivio-Kinnucan M. , Dietrich M. A. 
Published: January 2024

Abstract

Objective
To characterize the canine melanoma antigen recognized by the murine monoclonal antibody IBF9 as to its cellular location, molecular size, protein and glycogen contents, and distribution in cell lines.

Sample Population
7 cultured canine melanoma cell lines.

Procedure
Molecular characteristics of the antigen were determined by western blotting, enzymatic digestion studies, and tunicamycin inhibition studies. Distribution of the antigen in the cultured melanoma cell lines was determined by flow cytometry.

Results
The antigen consists of 2 proteins with molecular mass of 89 and 85 kd. Tunicamycin and enzymatic digestion studies indicated that these proteins contained little glycosylation. Immunogold and immunofluorescence studies localized the antigen to the cell surface. Antigen expression was consistent within each cell line, with > 90% of the cells positive for all cell lines except 1 (80%). Percentage of positive cells and relative intensity of immunostaining were constant throughout all phases of the cell cycle.

Conclusions
The antigen identified by MAB IBF9 is a well-conserved and highly expressed cell surface protein present during all phases of the cell cycle in all malignant canine melanoma cell lines examined.

Clinical Relevance
Because of consistency in expression, the antigen may have potential for use in dogs for melanoma immunodiagnostics and immunotherapy. (Am J Vet Res 1997;58:46–52)
Characterization of anatomic communications among the antebrachiocarpal, middle carpal, and carpometacarpal joints in cattle, using intra-articular latex, positive-contrast arthrography, and fluoroscopy
Authors: Desrochers André , St.-Jean Guy , Cash Walter C. , Hoskinson James J. , DeBowes Richard M. 
Published: January 2024

Abstract

Objective
To evaluate the frequency and sites of communication among the antebrachiocarpal, middle carpal, and carpometacarpal joints in cattle.

Animals
137 limbs were obtained from 72 fresh bovine cadavers submitted for necropsy because of problems unrelated to the carpus.

Procedure
1 of the 3 injection sites was randomly assigned to both carpi of each ox, and a mixture of latex and barium sulfate was injected into the joint. Communication between 2 or more joints was determined by the presence of latex and contrast material in a joint adjacent to the injected joint by examination of frozen sections, positive-contrast arthrography, and fluoroscopy.

Results
Communication existed among the 3 joints in 18 specimens (13.1%). The middle carpal joint and the carpometacarpal joint always communicated. The antebrachiocarpal joint communicated with the middle carpal joint between the ulnar and intermediate carpal bones. The middle carpal and carpometacarpal joints always communicated between the fourth and fused second and third carpal bones. In a few specimens, additional sites of communication were identified at the palmar aspect of the fourth carpal bone and the fused second and third carpal bones.

Conclusions and Clinical Relevance
Individual anatomic variation of the carpus in cattle should be considered when diagnostic or treatment protocols are established. (Am J Vet Res 1997;58:7–10)
Biochemical, histochemical, and immunohistochemical characterization of distal tibial osteochondrosis in horses
Authors: Lillich J. D. , Bertone Alicia L. , Malemud Charles J. , Weisbrode Steven E. , Ruggles Alan J. , Stevenson Sharon 
Published: January 2024

Abstract

Objective
To compare the biochemical, histochemical, and immunohistochemical profiles of articular cartilage from horses with naturally acquired distal tibial osteochondrosis (OC) with cartilage from a similar location in clinically normal horses.

Animals
9 affected horses (group 1, 16 OC lesions) and 4 control horses (group 2, 8 normal osteochondral specimens).

Procedure
OC specimens were collected during arthroscopic removal of the fragment, and control specimens were collected by aseptic osteotomy. Uronic acid, total protein, total glycosaminoglycan (GAG), chondroitin sulfate (CS), and keratan sulfate (KS) contents were determined. Histomorphologic, histochemical, and immunohistochemical examinations were performed on specimens after snap freezing at −80 C and cryosectioning. Monoclonal antibodies (MAB) 3B3 and 5D4 were applied for location of epitopes of CS and KS, respectively.

Results
OC lesions had significantly lower quantity of uronic acid, total GAG, and CS, compared with normal cartilage. OC cartilage had significantly less intense staining with toluidine blue, along with irregular cellularity and tidemark characteristics, compared with normal cartilage. Monoclonal antibodies 3B3 and 5D4 stained OC cartilage, whereas MAB 5D4 did not stain control cartilage. Additionally, MAB 3B3 and 5D4 stained the fibrous tissue that was found firmly attached to the OC lesion located between the parent distal portion of the tibia and OC fragment.

Conclusion
OC cartilage lesions of the distal intermediate ridge of the tibia in horses are biochemically, histochemically, and immunohistochemically distinct from normal cartilage from the same location. Results may reflect the inability of the chondrocyte of the developing joint to alter matrix components that would allow proper maturation and differentiation into bone. (Am J Vet Res 1997;58:89–98)
Spectro-temporal mapping of the surface electrocardiogram in clinically normal dogs
Authors: Calvert Clay A. , Kushner Lynn I. , Jacobs Gilbert J. , Brown John 
Published: January 2024

Abstract

Objectives
To establish data for selected variables of the signal-averaged ECG and determine whether sedation affects segment lengths and points within the terminal QRS complex where windows began.

Sample Population
Overtly healthy dogs with no detected abnormalities.

Procedure
Signal-averaged ECG (600 beats) were obtained from dogs in left-lateral recumbency, using X, Y, and Z leads with 26-gauge subdermal platinum electrodes. Frequency-domain analyses were performed by fast Fourier transform (FFT), using a postprocessing computer software package. Analyses were extracted from 30-, 40-, and 50-millisecond windowed (Blackman-Harris) segments of the terminal 10 or 20 milliseconds of the QRS complex and ST segment. Correlation ratios were calculated by cross-correlation of frequency spectra of each FFT in the range of 40 to 200 Hz. The reference spectrum was the last FFT (nearest the T wave). Spectro-temporal maps were plotted for each analysis.

Results
Noise levels were < 1 μV. Sedation resulted in less noise and slower heart rate, but did not affect results. Correlation ratios were not different among 30-, 40-, and 50-millisecond segments, but were lower when 20 (vs 10) milliseconds of the terminal QRS was included. Spectro-temporal maps were similar in all subjects.

Conclusions
Use of sedation facilitated the procedure without affecting results. Segment lengths of 40 and 50 milliseconds, beginning 10 milliseconds prior to the end of the QRS complex and analyzed in the range of 40 to 200 Hz, yielded correlation ratios > 67%, 95% of the time.

Clinical Relevance
Spectro-temporal mapping may identify dogs with ventricular late potentials (high-frequency signals commonly associated with myocardial fibrosis) that may be at increased risk of sudden death. (Am J Vet Res 1997;58:211–217)
Determination of an effective dose of eltenac and its comparison with that of flunixin meglumine in horses after experimentally induced carpitis
Authors: Hamm D. , Turchi P. , Johnson J. C. , Lockwood P. W. , Thompson K. C. , Katz T. 
Published: January 2024

Abstract

Objectives
To titrate a clinically effective eltenac dosage (0.1, 0.5, and 1.0 mg/kg of body weight), compared with vehicle only, and to compare efficacy of the most effective eltenac dosage with that of 1.1 mg of flunixin meglumine/kg.

Animals
40 healthy horses, ranked after model induction on the basis of lameness severity, were randomly assigned to 5 treatment groups, with 4 replicates of 10 horses each.

Procedure
On day -5, after surgical preparation of the left carpal region, 0.7 ml of Freund's complete adjuvant was injected into the intercarpal space. Horses were observed daily, from the day of carpitis induction to day 0, when stride length was used as the method of ranking horses for randomization to treatment assignment. Treatments were administered IV once daily for 3 consecutive days, starting on day 0. Prior to carpitis induction on day -5, and at time 0 (pretreatment). 2, 4, 12, 24, 36. 48, 60, 72, and 96 hours after treatment initiation, resting respiratory rate and pulse, rectal temperature, carpal circumference, carpal flexion angle, stride length, carpal hyperthermia, and signs of carpal pain were recorded.

Results
Compared with the vehicle and 0.1 mg of eltenac/kg, 0.5 and 1.0 mg/kg caused statistically significant improvements (ie, reduction of carpal circumference, increase in carpal flexion angle, and increase in stride length of the affected limb), but values did not differ significantly between the 2 dosages. Thus, a dose-response plateau for eltenac was reached at 0.5 mg/kg.
Comparison with flunixin meglumine at a dosage of 1.1 mg/kg did not indicate significant differences between the 2 treatment groups at the pivotal time of 96 hours for carpal circumference, carpal flexion angle, stride length, carpal hyperthermia, and signs of carpal pain. Adverse reactions were not observed.

Clinical Relevance
Under conditions of this study, a dosage plateau for eltenac was determined (0.5 mg/kg) that was statistically equivalent to eltenac (1.0 mg/kg) and flunixin meglumine (1.1 mg/kg) in a 3-day IV dosing regimen. (Am J Vet Res 1997;58:298–302)