bluuebunny/crossref_metadata_2025_split huggingface dataset:
Duration of effects of dietary fish oil supplementation on serum eicosapentaenoic acid and docosahexaenoic acid concentrations in dogs
Authors: Hansen Rodney A. , Ogilvie Gregory K. , Davenport Deborah J. , Gross Kathy L. , Walton Judy A. , Richardson Kristi L. , Mallinckrodt Craig H. , Hand Michael S. , Fettman Martin J. 
Published: January 2024

SUMMARY

Objective
To determine how long serum concentrations of ω-3 fatty acids remain elevated after cessation of dietary fish oil supplementation.

Animals
12 healthy Beagles.

Procedure
Baseline serum concentrations of linoleic acid, linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were measured. Dogs were then fed a diet supplemented with soybean oil or fish oil for 8 weeks, and serum fatty acid concentrations were measured while dogs were fed the experimental diets and for 18 weeks after they were switched to a maintenance diet.

Results
For dogs fed the fish oil diet, serum EPA and DHA concentrations were significantly increased by week 1 and remained increased for 7 (DHA concentration) or 3 (EPA concentration) weeks after dietary fish oil supplementation was discontinued.

Conclusions
In dogs, supplementation of the diet with fish oil may have effects for several weeks after dietary supplementation is discontinued.

Clinical Relevance
Studies of the effects of fish oil supplementation that use a crossover design should allow for an appropriate washout period. (Am J Vet Res 1998;59:864–868)
Use of peripheral temperature and core-peripheral temperature difference to predict cardiac output in dehydrated calves housed in a thermoneutral environment
Authors: Constable Peter D. , Walker Pamela G. , Morin Dawn E. , Foreman Jonathan H. , Thurmon John C. 
Published: January 2024

SUMMARY

Objective
To investigate the relation between cardiac output (CO) and peripheral (fetlock) temperature (PT) and core-peripheral (rectal-fetlock) temperature difference (CPTD) in dehydrated calves housed in a thermoneutral environment.

Animals
28 male dairy calves 3 to 10 days old.

Procedure
Severe dehydration and watery diarrhea were induced by administering diuretics (furosemide, hydrohlorothiazide, spironolactone) and sucrose solution. Cardiac output was measured by means of thermodilution, core temperature was determined by placing a digital thermometer in the rectum, and PT was measured by taping a thermistor to the left hind fetlock and insulating the thermistor from ambient air.

Results
In thermoneutral ambient temperatures (10 to 24 C), PT and CPTD were constant and independent of CO at normal or high CO values but were linearly dependent on CO below a critical value (78% of normal CO output). Regression equations were developed that predicted CO from measured PT or CPTD. At ambient temperatures below the lower critical temperature for neonatal calves (8 to 10 C), normal values for PT and CPTD in healthy calves were significantly different from those at thermoneutral ambient temperatures.

Conclusions and Clinical Relevance
Peripheral temperature and CPTD are practical, noninvasive, and inexpensive but only moderately useful methods for predicting CO in hemodynamically stable calves housed in a thermoneutral environment. Thus, these parameters are of some value in daily monitoring of the response to treatment and in determining need for IV fluid administration in dehydrated calves housed at a dry still-air temperature of 10 to 24 C but are of minimal to no value in calves housed at < 10 C. (Am J Vet Res 1998;59:874–880)
Influence of exogenous hyaluronan on synthesis of hyaluronan and collagenase by equine synoviocytes
Authors: Lynch Timothy M. , Caron John P. , Arnoczky Steven P. , Lloyd James W. , Stick John A. , Render James A. 
Published: January 2024

SUMMARY

Objective
To evaluate the influence of exogenous hyaluronan (HA) on in vitro synthesis of HA and collagenase by equine synoviocytes from normal and inflamed joints.

Animals
9 adult horses.

Procedure
Synoviocytes for culture were taken from the middle carpal joint of 3 horses with normal joints (control) and 6 horses with osteochondral fractures (principal). Synoviocytes were propagated in monolayer cultures and were incubated with 3 commercial HA products at concentrations of 0, 200, 400, and 1,500 μg/ml. Newly synthesized HA was radiolabeled with [3H]glucosamine and quantified by cetylpyridinium chloride precipitation and liquid scintillation counting. The hydrodynamic size of radioactive HA was determined by high-performance liquid chromatography, and collagenase activity was evaluated by use of a quantitative radioactive collagen film assay.

Results
Exogenous HA influenced neither the rate of synthesis nor the hydrodynamic size of the newly produced HA by control or principal cell cultures. Culture supernatants from abnormal synovium, exposed to 400 and 1,500 μg of exogenous HA/ml, contained significantly more collagenase activity than did those exposed to lower concentrations.

Conclusion
Although HA is thought to have beneficial effects in equine arthropathies, the principal mechanisms of action of HA do not appear to be stimulation of synthesis of HA of augmented molecular weight or marked inhibition of collagenase synthesis. (Am J Vet Res 1998;59:888–892)
Alteration in adrenocortical function in horses with recurrent airway obstruction after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively
Authors: Rush Bonnie R. , Worster Allison A. , Flaminio M. Julia B. F. , Matson Charles J. , Hakala Joyce E. 
Published: January 2024

Abstract

Objective
To determine alteration in adrenocortical function in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively.

Animals
6 horses with inducible and reversible heaves.

Procedure
Episodes of heaves were induced by exposure to moldy hay and straw for 7 days (natural challenge). Horses then underwent treatment (aerosolized beclomethasone, parenterally administered dexamethasone, and aerosolized propellant) for 7 days. Horses remained in the mold-contaminated environment for 7 days after discontinuation of drugs. Adrenocortical function was determined by serial evaluation of Cortisol concentration in serum obtained on days 0, 7, 9, 12, 14, 16, 19, and 21. Adrenocorticotropic hormone stimulation testing was performed in 4 horses/treatment group on days 0, 7, 14, and 21.

Results
Endogenous Cortisol production was suppressed in beclomethasone- and dexamethasone-treated horses within 2 days of treatment but recovered to values similar to those in propellant-treated horses approximately 2 and 4 days after discontinuation of drugs. Serum Cortisol concentration in propellant-treated horses gradually decreased during the study and was significantly lower than baseline on days 14, 16, 19, and 21. Mean increase in serum Cortisol concentration in response to ACTH stimulation testing after beclomethasone and dexamethasone administration did not differ significantly from the response observed in propellant-treated horses.

Conclusions
Aerosol and parenteral administration of beclomethasone and dexamethasone, respectively, suppressed adrenocortical function; however, endogenous cortisol production resumed approximately 2 and 4 days after discontinuation of drugs. Responsiveness to ACTH stimulation testing was not affected by the 7-day treatment period. (Am J Vet Res 1998;59:1044–1047)
Effects of a prostaglandin E1 analogue, misoprostol, on renal function in dogs receiving nephrotoxic doses of gentamicin
Authors: Davies Charlotte , Forrester S. Dru , Troy Gregory C. , Saunders Geoffrey K. , Shell Linda G. , Johnston Spencer A. 
Published: January 2024

Abstract

Objective
To determine whether the prostaglandin E1 analogue, misoprostol, could preserve renal function in dogs receiving nephrotoxic doses of gentamicin.

Animals
12 (6/group) healthy sexually intact male dogs.

Procedure
All dogs were given high doses of gentamicin (10 mg/kg of body weight, IV, q 8 h, for 8 consecutive days). Six dogs (treatment group) received misoprostol (3 μg/kg, PO, q 8 h for the duration of the study) and 6 dogs (control group) received vehicle (1 capsule, PO, q 8 h). Renal function was assessed before treatment (day 0) and on days 3, 6, 9, and 11 after initiation of treatment by measurement of serum biochemical variables, urine specific gravity, and exogenous creatinine clearance. Serum electrolyte and protein concentrations and presence of proteinuria, glycosuria, and cylindruria were also determined. At the end of the study, renal histopathologic changes were evaluated.

Results
Dogs receiving misoprostol had significant reduction in exogenous creatinine clearance with time, compared with dogs receiving vehicle (P = 0.0264). Dogs receiving misoprostol tended to develop more severe azotemia, hyperphosphatemia, and renal histopathologic changes; however, results were not significantly different between groups.

Conclusion
Misoprostol (3 μg/kg, PO, q 8 h) did not preserve renal function and may have exacerbated gentamicin-induced nephrotoxicosis in this group of dogs.

Clinical Relevance
Supplementation of vasodilatory prostanoids may exacerbate renal dysfunction in dogs receiving high doses of gentamicin. (Am J Vet Res 1998;59:1048–1054)
Validation of predictive equations for use of deuterium oxide dilution to determine body composition of dogs
Authors: Burkholder William J. , Thatcher Craig D. 
Published: January 2024

Abstract

Objective
To validate equations predicting body composition of dogs, using deuterium oxide dilution.

Animals
38 female and 37 male dogs selected by defined body weight and body condition criteria.

Procedure
Measured equilibrated deuterium concentration in serum after IV administration of isotope was used to determine isotope space and predict body water, fat, nitrogen, and ash contents determined from analysis of homogenized carcass. Equations predicting body composition were derived, using regression analysis, and were validated, using data-splitting techniques.

Results
Deuterium space (in kilograms) overestimated kilograms of body water content by mean 21.8% ± SD of 4.18%. Regression equations were derived and validated to predict kilograms of body water and ash from kilograms of deuterium space, and proportions of body water, fat, nitrogen, and ash from proportion of deuterium space. Coefficients of determination (r2) and means of standard errors of estimating new values (SEE) were, respectively, 0.993 and 0.4 kg for body water content, and 0.942 and 0.08 kg for ash content. For proportions, SEE were 2.0, 2.7, 0.1, and 0.4% for body water, fat, nitrogen, and ash, respectively. Two factors, time for isotope equilibration and whether samples were processed by vacuum sublimation, improved SEE for proportion of body water from 2.0 to 1.3% and of fat from 2.7 to 1.8%. Equations predicting absolute quantities of fat and nitrogen could be derived but not validated.

Conclusions
Deuterium dilution can be used to predict body composition of dogs with precision equal to that determined for other species. (Am J Vet Res 1998;59:927–937)
Mechanical correlations derived from segmental histologic study of the equine superficial digital flexor tendon, from foal to adult
Authors: Crevier-Denoix Nathalie , Collobert Claire , Sanaa Moez , Bernard Nadine , Joly Cécile , Pourcelot Philippe , Geiger Didier , Bortolussi Claude , Bousseau Benoît , Denoix Jean-Marie 
Published: January 2024

Abstract

Objective
To assess histologic variations of the equine superficial digital flexor tendon (SDFT) according to site and to horse age and activity, and to correlate these data with reported segmental mechanical results.

Sample Population
Superficial digital flexor tendons isolated from 42 horses 0.5 hour to 23 years old.

Procedure
7 segments of each SDFT were delimited and submitted for conventional histologic examination. Each segment was examined and graded for fiber undulation, cellularity, number and size of interfascicular connective spaces (ICS), presence or absence of focal and diffuse chondroid metaplasia, and differentiation of the dorsal (DB) and palmar (PB) borders of the tendon.

Results
Fiber undulation and cellularity significantly decreased with age. The proximal and middle metacarpal segment fibers were significantly less undulated and their ICS were smaller than those of the other segments, especially in old horses. Focal chondroid metaplasia developed from 5 years onward, mainly in the sesamoidean segments. Diffuse chondroid metaplasia was characteristic of the digital region in horses > 6 years old. The DB of the metacarpodigital region tended to differentiate into fibrocartilage in association with age. The PB was generally differentiated as nonfascicular dense connective tissue. Activity induced a decrease in the number and size of the ICS.

Conclusions
The lesser undulation of the proximal and middle metacarpal segments fibers can be correlated to their mechanical behavior (stress-strain curve) and relative weakness within the SDFT. Focal chondroid metaplasia and fibrocartilage on the DB are normal features, related to the compression stresses undergone by the sesamoidean region of the tendon. (Am J Vet Res 1998;59:969–977)
Efficacy of a drug combination of praziquantel, pyrantel pamoate, and febantel against giardiasis in dogs
Authors: Barr Stephen C. , Bowman Dwight D. , Frongillo Marguerite F. , Joseph Steven L. 
Published: January 2024

Abstract

Objective
To evaluate efficacy of a combination of praziquantel, pyrantel pamoate, and febantel at 2 dosages for treating naturally acquired giardiasis in dogs.

Animals
6 male and 9 female Beagles.

Procedure
Dogs were identified as naturally infected with Giardia sp, using the zinc sulfate concentration technique (ZSCT), and were allocated to 1 of 3 groups. Group-1 dogs were treated orally with a praziquantel (5.4 to 7 mg/kg of body weight), pyrantel pamoate (26.8 to 35.2 mg/kg), and febantel (26.8 to 35.2 mg/kg) combination, every 24 hours for 3 doses. Group-2 dogs were treated with the combination once. Group-3 dogs were nontreated controls. Four fecal samples were examined, using the ZSCT, from each dog of each group within 6 days of the last treatment. Dogs were considered to have giardiasis if 1 or more of the fecal samples had positive results for Giardia cysts. Dogs were examined daily for at least 10 days after the last treatment.

Results
Giardia cysts were not detected in the feces of any group-1 dog or in the feces of 2 of 5 group- 2 dogs. Cysts were detected in the feces of 5 of 5 group-3 (nontreated control) dogs. Signs of toxicosis were not observed in any dog.

Conclusion and Clinical Relevance
The current labeled dose (for treatment of various nematodes and cestodes, but not Giardia sp) of the combination given orally once reduces cyst excretion in Giardia-infected dogs, and should be considered for treatment of dogs shedding Giardia cysts, whether or not they have clinical signs of infection. (Am J Vet Res 1998; 59:1134-1136)
Effects of the major Pasteurella multocida porin on bovine neutrophils
Authors: Galdiero Massimiliano , Palomba Eugenio , De Luisa , Vitiello Mariateresa , Pagnini Pietro 
Published: January 2024

Abstract

Objective
To evaluate in vitro effect of the major fraction of outer membrane proteins of Pasteurella multocida with porin-like activities on some biological functions of bovine neutrophils.

Animals
Neutrophils from 5 adult cattle.

Procedure
Variations in such biological processes as actin polymerization and chemotaxis and evaluation of hydrogen peroxide attributable to variable concentrations of P multocida were recorded and compared. Data were obtained, using the porin and lipopolysaccharide (LPS) isolated from a strain of P multocida cultivated in brain-heart infusion (BHI) broth. Various concentrations of porin and LPS were analyzed to evaluate changes in functional activation and microbicidal activity of bovine neutrophils.

Results
The 37.5-kd major polypeptide of the outer membrane of P multocida was isolated. Presence of this porin was significantly correlated with variations of some biological functions of bovine neutrophils. These immunocompetent cells had a concentration-dependent increase in actin polymerization and chemotactic activity. A concentration-dependent variation in the oxidative burst also was observed.

Conclusions
The porins of gram-negative bacteria affect several biological functions of cells involved in the immune response as well as in inflammation. Significant correlation of results of in vitro experiments also was identified between porin and LPS effect. Pretreatment of bovine neutrophils with various concentrations of porin always caused a concentration-dependent increase in examined biological activities. (Am J Vet Res 1998;59:1270–1274)
Characterization of a Pasteurella haemolytica A1 mutant deficient in production of three membrane lipoproteins
Authors: Murphy George L. , Whitworth Lisa C. , Confer Anthony W. , Gaskins Janet D. , Pandher Karamjeet , Dabo S. Mady 
Published: January 2024

Abstract

Objective
To determine whether a Pasteurella haemolytica A1 mutant that is unable to produce membrane lipoproteins has reduced susceptibility to complement-mediated killing, and to characterize the mutant strain.

Sample Population
12 sera from cattle resistant to P haemolytica challenge exposure after vaccination with P haemolytica or its antigens, or after natural exposure.

Procedures
Complement-mediated killing assays were performed, using wild-type and mutant strains and, as antibody source, various immune sera from cattle that were resistant to P haemolytica challenge exposure. Antibody response to whole-cell antigens produced by mutant and wild-type strains, production of outer membrane proteins and iron-regulated outer membrane proteins by the 2 strains, and growth of the 2 strains in various media were analyzed.

Results
Compared with wild-type P haemolytica, the lipoprotein mutant strain had increased susceptibility to bovine complement-mediated killing. Aside from the lipoproteins that are not produced by the mutant, immunoblot analysis did not reveal differences between immunoreactive antigens that are produced by the 2 strains. Some iron-regulated, outer membrane proteins, which usually are only produced by P haemolytica under iron-deficient conditions, were produced constitutively by the mutant. The mutant grew to a lower final cell density and at a lower rate under conditions likely to reflect those encountered in vivo.

Conclusions
Lack of 3 membrane lipoproteins resulted in enhanced susceptibility to bovine complement-mediated killing. Site-specific mutagenesis of genes encoding P haemolytica membrane lipoproteins alters production of iron-regulated outer membrane proteins by P haemolytica. Growth characteristics of the mutant suggested that it may have reduced capacity for survival in vivo. (Am J Vet Res 1998;59:1275-1280)
Evaluation of automated methods of measuring hemoglobin and hematocrit in horses
Authors: Sorrell-Raschi Laurie A. , Tomasic Michael 
Published: January 2024

Abstract

Objective
To evaluate the accuracy of 3 automated methods of determining Hct and hemoglobin (Hb) concentration, compared with manual methods.

Animals
22 clinically normal adult horses of various breeds.

Procedure
A blood sample was obtained from each horse. Six dilutions (representing Hct of 0, 10, 20, 40, 60, or 70%) were prepared from each sample and analyzed, using 1 of 2 blood gas analyzers or a hemoximeter (for automated determinations) or the Wintrobe macrohematocrit and cyanmethemoglobin methods (for manual determinations). Regression analysis was used to determine mean slope relationships between Hct and Hb measurements obtained by use of manual versus automated methods. Slopes were compared, using Student's t-test.

Results
Of the 3 automated methods examined, only 1 blood gas analyzer reported Hct and Hb values that were not significantly different from those determined by use of manual methods; however, this analyzer could not report Hb concentrations below 2.5 g/dl. The other blood gas analyzer reported values for Hct and Hb concentrations that were consistently higher than those obtained by use of manual methods at Hct ≤ 20% and Hb ≤ 6.6 g/dl. The hemoximeter yielded more accurate results if the Hb concentration was between 6.6 and 20 g/dl.

Conclusion
Although there were some limitations in measuring at low Hb concentrations, the method of determining Hb concentration and Hct with blood gas analyzer 2 was more accurate than that with blood gas analyzer 1 (Hct and Hb concentration) or the hemoximeter (Hb only). (Am J Vet Res 1998; 59:1519-1522)
Reproducibility of breath hydrogen concentration measurements in dogs after change of diet
Authors: Bissett S. A. , Spohr A. , Guilford W. G. , Haslett S. J. 
Published: January 2024

Abstract

Objective
To assess reproducibility of breath hydrogen (H2) concentration measurements in dogs on 3 consecutive days after introduction of a new diet.

Animals
10 healthy colony-source dogs.

Procedure
Dogs were fed a commercial pet food for a minimum of 10 days before introduction of a high-carbohydrate commercial diet. Expired breath samples were collected at baseline and every 90 minutes for 18 hours on the first 3 days after introduction of the new diet. The area under the curve (AUC) for breath H2 concentration versus time on days 1,2, and 3 were compared by use of repeated-measures ANOVA.

Results
The (AUC) did not differ significantly among test days 1, 2, and 3.

Conclusions
Expired breath H2 concentration in dogs indicated good reproducibility during the first 3 days after introduction of a new diet.

Clinical Relevance
It is not necessary to provide a period for adaptation to a test diet prior to performing breath H2 tests in dogs. (AmJ Vet Res1998;59: 1523-1525)
Interleukin 8 response by bovine mammary epithelial cells to lipopolysaccharide stimulation
Authors: Boudjellab N. , Chan-Tang H. S. , Li X. , Zhao X. 
Published: January 2024

Abstract

Objective
To determine whether an established bovine mammary epithelial cell line expresses interleukin 8 (IL-8) mRNA and synthesizes antigenic IL-8 in response to lipopolysaccharide (LPS) stimulation.

Sample Population
A bovine mammary epithelial cell line (MAC-T).

Procedure
mRNA was isolated from cells stimulated with graded concentrations of LPS. The first strand of IL-8 cDNA was synthesized, using a reverse transcriptase (RT) reaction with a specific oligonucleotide. Amplification of IL-8 cDNA was obtained by use of polymerase chain reaction (PCR). The MAC-T-derived antigenic IL-8 was quantified by use of a commercial anti-human IL-8 kit in a sandwich ELISA.

Results
RT-PCR revealed expression of MAC-T-derived mRNA within the first hour after stimulation with LPS. Expression of IL-8 mRNA was correlated to production of IL-8 protein detected in medium by use of the sandwich ELISA. Amounts of antigenic IL-8 increased in a dose- and time-dependent manner, and were maximal (57 pg/ml) at 48 hours after stimulation with 20 μg of LPS/ml.

Conclusions
MAC-T cells secrete IL-8 in response to stimulation with LPS in a dose- and time-dependent manner. The results were consistent with our hypothesis that mammary gland epithelial cells can be a source of IL-8 during the early stage of mastitis. Therefore, IL-8 may have a pivotal role in resolving bacterial infections. (Am J Vet Res 1998;59:1563-1567)