bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of the breath hydrogen test to assess the effect of age on orocecal transit time and carbohydrate assimilation in cats
Authors: Papasouliotis K. , Sparkes A. H. , Gruffydd-Jones T. J. , Cripps P. J. , Harper E. J.
Published: January 2024

Objective

To evaluate the effect of age on orocecal transit time (OCTT) in cats, using the breath hydrogen test, and to assess potential differences in nutrient absorption.

Animals

27 healthy cats.

Procedure

Cats were allocated to the following 3 groups on the basis of age: group A (9 kittens, 5 to 7 months old), group B (9 young adults, 3 to 5 years old), and group C (9 older cats, 12 to 15 years old). Cats were fed a standard canned diet for 2 weeks prior to measurement of OCTT. Exhaled hydrogen concentration (parts per minute [ppm●min]) was monitored for 8 hours after feeding 60 g of the canned diet.

Results

Mean OCTT in group-A cats was 203 minutes (range, 90 to 345 minutes), which was significantly different from that in group-B (317 minutes; range, 180 to 435 minutes) and group-C (309 minutes; range, 225 to 375 minutes) cats. Median area under the breath hydrogen excretion time curve (ppm●min) for the 8-hour monitoring period, first 45 minutes, and 105 minutes after OCTT for the 3 groups was not significantly different among groups.

Conclusions

Kittens had significantly faster OCTT than did adult cats. (Am J Vet Res 1998;59:1299–1302)
Pathologic findings in dogs with shock induced by intravenous administration of heartworm extract
Authors: Kitoh Katsuya , Kitagawa Hitoshi , Sasaki Yoshihide
Published: January 2024

Objective

To examine pathologic findings in dogs with shock induced by IV administration of heartworm (HW) extract.

Animals

22 mixed-breed adult dogs.

Procedures

Heartworm extract was administered IV, and pathologic changes in dogs that died or were euthanatized at 24 hours were examined.

Results

The most severe lesions observed during initial collapse were centralobular congestion in the liver, hemorrhage and edema in the gallbladder wall, and congestion and hemorrhage in mucous membranes of the gastrointestinal tract. These findings disappeared with recovery from collapse. Hyalinization of venous walls of the liver and cardiac muscle were observed in dogs that died during initial collapse. Focal coagulation necrosis in hepatic cells was seen in dogs that were euthanatized at 24 hours. One dog with profuse bloody diarrhea that died during secondary collapse had severe hemorrhage in mucous membranes of the large intestine.

Conclusion

Heartworm extract appeared to contain some substances constricting hepatosplanchnic vessels and some toxic substances that injured the smooth muscle of venous walls, cardiac muscle, and hepatic cells directly or indirectly.

Clinical Relevance

The shock-inducing substances in HW extract may have an important role in the pathophysiologic mechanism of HW disease, and investigation of them may contribute to prevention of the shock reaction attributable to microfilaricide and adulticide use. (Am J Vet Res 1998;59:1417–1422)
Evaluation of selective inhibition of canine cyclooxygenase 1 and 2 by carprofen and other nonsteroidal anti-inflammatory drugs
Authors: Ricketts Anthony P. , Lundy Kristin M. , Seibel Scott B.
Published: January 2024

Objective

To evaluate the activity of carprofen and other nonsteroidal anti-inflammatory drugs (NSAID) against isozymes of canine cyclooxygenases (COX1 and COX2).

Procedure

Constitutive COX1 was obtained from washed canine platelets, and COX2 was obtained from a canine macrophage-like cell line that was induced with endotoxin. Activity of carprofen and other NSAID against COX1 and COX2 was compared. Dose-response curves were plotted, and calculations were performed to identify concentrations that caused 50% inhibition (IC50[μM]) for each isozyme. Ratio of the COX1-to-COX2 IC50 was used as a measure of isozyme selectivity.

Results

Of the compounds evaluated, carprofen had the greatest selectivity for COX2. Potency of carprofen for canine COX2 was more than 100-fold greater than for canine COX1. Inhibition of canine COX2 (IC50, 0.102 μM) for the racemic mixture of carprofen (S and R stereoisomers) was primarily attributable to the S enantiomer (IC50, 0.0371 μM), which was approximately 200-fold more potent than the R enantiomer (IC50, 5.97 μM). Nimesulide had the next highest selectivity for COX2 (38-fold), and tolfenamic acid and meclofenamic acid had 15-fold selectivity for COX2. The other compounds tested did not have substantial selectivity for canine COX2 or were more selective for canine COX1.

Conclusions

Carprofen was found to be a potent inhibitor of canine COX2. Of the compounds tested, carprofen had the highest selectivity for canine COX2.

Clinical Relevance

The selectivity of carprofen for canine COX2 may be an important factor for its use in dogs. (Am J Vet Res 1998;59:1441–1446)
Intensity-dependent effects of acute submaximal exercise on the pharmacokinetics of bromsulphalein in horses
Authors: Dyke T. M. , Sams R. A. , Hinchcliff K. W.
Published: January 2024

Objective

To determine the effects of acute exercise on hepatic blood flow by studying hepatic clearance of bromsulphalein for several submaximal exercise intensities.

Animals

8 adult Standardbred mares.

Procedure

Horses were subjected to 4 submaximal exercise intensities (resting and 40, 60, and 80% maximal oxygen consumption). After horses had been running at the required treadmill speed for 1 minute, bromsulphalein (BSP; 5 mg/kg of body weight, IV) was administered during a 45- to 60-second period, and horses continued at the desired speed for an additional 15 minutes. Blood samples were collected at 2-minute intervals for 30 minutes, and plasma concentration of BSP was determined by spectrophotometry. Estimates of pharmacokinetic variables were compared among the 4 exercise intensities, using a Friedman repeated-measures analysis on ranks and linear regression.

Results

Median values for clearance of BSP from blood and plasma decreased significantly with exercise and was linearly related to exercise intensity. Exercise-induced differences were not detected in the volume of distribution of BSP. Elimination half-life of BSP increased significantly with increasing exercise intensity and was linearly related to exercise intensity.

Conclusions

Acute submaximal exercise has a dramatic effect on clearance of BSP in horses. Presumably, exercise-induced decreases in splanchnic blood flow limit blood flow to the liver, decreasing hepatic clearance of BSP and leading to persistence of plasma concentrations of BSP.

Clinical Implications

Drugs that are efficiently extracted by the liver may have decreased hepatic clearance when horses exercise at submaximal intensities. (Am J Vet Res 1998;59:1481–1487)
Protection against infection and abortion induced by virulent challenge exposure after oral vaccination of cattle with Brucella abortus strain RB51
Authors: Elzer Philip H. , Enright Fred M. , Colby Lesley , Hagius Sue D. , Walker Joel V. , Fatemi Masi B. , Kopec John D. , Beal Victor C. , Schurig Gerhardt G.
Published: January 2024

Objectives

To determine efficacy of orally administered Brucella abortus vaccine strain RB51 against virulent B abortus challenge exposure in cattle as a model for vaccination of wild ungulates.

Animals

20 mixed-breed beef cattle obtained from a brucellosis-free herd.

Procedure

Sexually mature, Brucella-negative beef heifers were vaccinated by mixing > 1010 viable RB51 organisms or diluent with their feed. Heifers were fed individually and consumed their entire ration. Each heifer received approximately 3×1010 colony-forming units (CFU). Six weeks after oral vaccination, heifers were pasture-bred to brucellosis-free bulls. At approximately 186 days' gestation, heifers were challenge exposed conjunctively with 107 CFU of virulent B abortus strain 2308.

Results

Vaccination with the rough variant of B abortus RB51 did not stimulate antibodies against the O-polysaccharide (OPS) of B abortus. After challenge exposure and parturition, strain 2308 was recovered from 80% of controls and only 20% of vaccinates. Only 30% of the vaccinates delivered dead, premature, or weak calves, whereas 70% of the controls had dead or weak calves.

Conclusions

Cattle vaccinated orally with the rough variant of B abortus strain RB51 develop significant (P< 0.05) protection against abortion and colonization and do not produce OPS-specific antibodies.

Clinical Relevance

Results encourage further investigation into use of strain RB51 to vaccinate wild ungulates (elk and bison) orally. (Am J Vet Res1998; 59:1575-1578)Vol 59, No. 12, December 1998
Molecular, clinical, and pathologic comparison of two distinct strains of Haemobartonella felis in domestic cats
Authors: Foley Janet E. , Harrus Shimon , Poland Amy , Chomel Bruno , Pedersen Niels C.
Published: January 2024

Objective

To characterize 2 strains of Haemobartonella felis by use of molecular techniques.

Animals

35 specific-pathogen-free cats, 6 months to 4 years old.

Procedure

Intraperitoneal or IV inoculation with blood containing H felis small form (Hfsm, 18 cats) or H felis large form (Hflg, 11 cats); 6 cats were uninfected controls. Hfsm was evaluated for capability to cross-protect against the more virulent Hflg. Morphology of both strains was compared by light microscopy of Wright-Giemsa-stained blood smears, and the 16S rRNA genes were sequenced.

Results

Infection with Hflg induced signs of depression, fever, and severe macrocytic normochromic anemia with nucleated erythrocytes. More than 95% of erythrocytes were parasitized. Inoculation with Hfsm and uninfected control blood induced mild or no clinical signs and no hematologic abnormalities. Anti-Hfelis lgG was first detected on postinoculation day (PID) 21, and increased to maximal titer of 400 by PID 28. Reactivated infection was observed in 8 of 29 cats (4 Hfsm and 4 Hflg), with 5% parasitized erythrocytes during the later attack. On PID 8, Hflg-inoculated cats had positive results of polymerase chain reaction analysis (PCR) that persisted until cats were treated with doxycycline or oxytetracycline; Hfsm-inoculated cats had positive PCR results that persisted for duration of observation (3 months).

Conclusions

Genetically and morphologically distinct strains of H felis infect cats in the field. The level of genetic difference suggested that these strains may be different species or genera.

Clinical Relevance

PCR is a critical diagnostic aid to detect occult Haemobartonella spp infection, as well as response to treatment and clearance of the organism. (Am J Vet Res 1998;59:1581-1588)
Effect of high-intensity exercise on arterial blood gas tensions and upper airway and cardiac function in clinically normal Quarter Horses and horses heterozygous and homozygous for hyperkalemic periodic paralysis
Authors: Maxson-Sage A. , Parente E. J. , Beech J. , Lindborg S. , May L. L. , Teleis D. C.
Published: January 2024

Objective

To determine the effect of exercise on arterial blood gas tensions and upper airway and cardiac function in clinically normal Quarter Horses and horses heterozygous and homozygous for hyperkalemic periodic paralysis (HYPP).

Animals and Procedure

5 clinically normal Quarter Horses, and 5 heterozygous and 2 homozygous HYPP-affected horses were examined before, during, and after exercise on a high-speed treadmill. Arterial blood gas tensions, ECG, and echocardiogram were obtained prior to exercise. Upper airway endoscopy, collection of arterial blood samples, and continuous electrocardiography were performed during a high-intensity stepwise exercise test. An ECG was obtained within 1 minute after completion of the final step.

Results

None of the horses homozygous or heterozygous for HYPP had signs of weakness or muscle fasciculations before, during, or after exercise. Horses homozygous for HYPP had intermittent laryngospasm, dynamic pharyngeal collapse, and appreciable hypoxemia, hypercapnia, and ventricular premature contractions during exercise. Heterozygous and clinically normal horses did not have any abnormalities. Potassium concentration increased significantly above the baseline reference range during exercise in all groups of horses.

Conclusions

Horses homozygous for HYPP had laryngospasm and dynamic pharyngeal collapse associated with exercise, most likely secondary to increase in potassium concentration. Upper airway dysfunction is the most likely cause of hypoxemia and hypercapnia. Cardiac arrhythmias were most likely caused by a combination of hypoxemia and hyperkalemia. (Am J Vet Res 1998;59:615–618)
Hemodynamic effects of thyroidectomy in sedentary horses
Authors: Vischer Carol M. , Foreman Jonathan H. , Constable Peter D. , Benson G. John , Kline Kevin H. , Freeman David E. , Campbell Karen L. , Grubb Tamara L.
Published: January 2024

Objective

To investigate hemodynamic effects of thyroidectomy in horses at rest.

Animals

6 healthy aged Quarter Horse mares.

Procedure

Horses were monitored for 5 months before and 4 weeks after thyroidectomy and for an additional 4 weeks after administration of thyroid hormone supplement (2.5 µg of thyroxine/kg of body weight, PO, q 12 h, and 0.6 µg of triiodothyronine/kg, PO, q 12 h). Responses to thyroid-stimulating hormone (TSH) were measured before and 4 weeks after thyroidectomy. Other variables monitored daily were resting rectal temperature (T), heart rate (HR), respiratory rate (RR), and body weight (BW), Monthly cardiac output (Q), blood volume (BV), plasma volume (PV), standard electrocardiographic measures, systolic and right ventricular blood pressure, and HR responses were determined after IV administration of isoproterenol and phenylephrine. Variables were analyzed by use of repeated-measures ANOVA.

Results

Complete thyroidectomy was confirmed by minimal response to TSH 4 weeks after surgery. Resting HR, RR, T, Q, and β-adrenergic responsiveness to isoproterenol decreased significantly after thyroidectomy. Resting T, Q, and β-adrenergic responsiveness increased after administration of supplement and was not significantly different from euthyroid values. Blood volume and PV increased significantly after thyroidectomy but did not return to euthyroid values despite administration of supplement. Response to phenylephrine was minimally different between treatments.

Conclusions and Clinical Relevance

Thyroidectomy in horses caused decreased resting HR, RR, T, Q, and isoproterenol responsiveness and increased BV, PV, PQ interval, and QT interval corrected for HR. Some of these surgically induced changes appeared to be partially reversed by administration of thyroid hormone supplement. (Am J Vet Res 1999;60:14–21)
Regulation of α-melanocyte-stimulating hormone secretion from the pars intermedia of domestic cats
Authors: Kemppainen Robert J. , Peterson Mark E.
Published: January 2024

Objective

To identify factors regulating secretion of α-melanocyte-stimulating hormone (α-MSH) from the pars intermedia (PI) of the pituitary gland of cats.

Animals

28 healthy adult cats.

Procedure

Indwelling catheters were placed in 1 jugular vein of each of 7 to 10 cats, depending on treatment group. Sixteen hours later, 3 blood samples were collected for determination of baseline plasma hormone concentrations, and saline solution or a test substance (haloperidol, corticotropin-releasing hormone, bromocriptine, isoproterenol, insulin, or dexamethasone) was administered via the catheter. Subsequent blood samples were collected at regular intervals for up to 240 minutes after injection. Concentrations of ACTH, cortisol, and α-MSH were measured in plasma by use of specific radioimmunoassays. Cats were rested for at least 3 weeks between experiments.

Results

Administration of haloperidol and isoproterenol resulted in increased, and bromocriptine and insulin in decreased, circulating concentrations of α-MSH from baseline. ACTH and plasma cortisol concentrations increased after administration of all test substances except dexamethasone. Dexamethasone injection resulted in decreased plasma concentrations of ACTH and cortisol.

Conclusions

Secretion of α-MSH from the PI of cats appears to be inhibited by dopaminergic activity and stimulated by β-adrenergic influences. Activation of secretion of α-MSH from the PI can be dissociated from activation of secretion of other proopiomelanocortin-derived peptides, such as ACTH, arising from the pars distalis. Regulation of secretory activity of the PI of cats resembles that of rats. (Am J Vet Res 1999;60:245–249)
Purification and biochemical characterization of equine pulmonary surfactant protein D
Authors: Hobo Seiji , Ogasawara Yoshinori , Kuroki Yoshio , Akino Toyoaki , Yoshihara Toyohiko
Published: January 2024

Objective

To characterize surfactant protein D (SP-D) isolated from bronchoalveolar lavage fluid (BALF) of healthy horses.

Sample Population

BALF from 10 Thoroughbreds (5 males, 5 females; 26 to 40 months old) without history or clinical signs of respiratory tract disease.

Procedure

BALF was obtained and centrifuged at 33,000 × g. The supernatant was applied to a mannose-Sepharose 6B affinity column in the presence of calcium, and the bound protein fraction was analyzed by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblot analysis; amino acid composition was determined and partial sequencing was done. Phospholipid binding and liposome aggregation assay were performed, using purified proteins.

Results

The protein isolated by use of mannose affinity matrices was SP-D. It bound carbohydrates and phosphatidylinositol, which are the characteristic features of SP-D isolated from other animal species. Amino acid analysis and partial primary sequence of the isolated protein indicated high homology with rat and human SP-D. Furthermore, immunoblot analysis indicated that equine SP-D reacted with human and rat SP-D-specific antibodies.

Conclusion and Clinical Relevance

SP-D exists in equine lungs; its measurement may be useful in evaluating equine lung disease. (Am J Vet Res 1999;60:368–372)
Identification of serotype by use of serologic assay and detection of the enterotoxin gene of Escherichia coli by means of a polymerase chain reaction assay for isolates from pigs, chickens, and cows
Authors: Jung Hee Kon
Published: January 2024

Objective

To serotype an enterotoxin gene from Escherichia coli isolated from cows, pigs, and chickens in Korea.

Sample population

Isolates from 37 cows with mastitis, 51 diarrheic pigs, and 5 diarrheic chickens.

Procedure

Serogroups and serotypes were identified by slide agglutination testing, using pathogenic E coli sera. Detection of E coli enterotoxins by use of reversed passive latex agglutination and ELISA was compared by proving existence of the gene by polymerase chain reaction (PCR) analysis.

Results and Conclusions

Detection of E coli enterotoxin by either method was positive for 1 strain (O20:H10; heat-labile enterotoxin [LP+], heat-stable enterotoxin [STa+]; isolation rate, 2%) and 3 other strains (0111:H10, 0119:H9, and 0125:H6, STa+; isolation rate, 5.9%) isolated from fecal specimens obtained from diarrheic pigs. The E coli enterotoxin genes were identified by use of PCR analysis in 1 strain containing the 417- and 163-base pair (bp) genes (LT+, Sta+; O20:H10) and in 3 strains containing only the 163-bp gene (STa+; 0111:H10, 0119:H9, and 0125:H6).

Clinical Relevance

Serotyping of E coli enterotoxin may be used to analyze patterns of transmission among species of domestic animals. (Am J Vet Res 1999;60:468-472)
Systemic dexamethasone concentration in horses after continued topical treatment with an ophthalmic preparation of dexamethasone
Authors: Spiess Bernhard M. , Nyikos Sibylle , Stummer Eva , Sahin Ali , Naegeli Hanspeter
Published: January 2024

Objective

To determine concentrations of dexamethasone in serum and urine of horses treated repeatedly with a topically administered ophthalmic dexamethasone preparation.

Animals

4 clinically normal horses (2 mares, 2 geldings).

Procedure

0.1% dexamethasone ophthalmic ointment was administered to the left eye of each horse every 5 to 9 hours for 8 consecutive days, yielding an estimated cumulative dexamethasone dose of 6.4 μg/kg of body weight. Serum and urine samples were obtained before the first dexamethasone treatment, on days 4 and 8 of treatment, and 24, 48, and 96 hours after cessation of treatment. To detect small concentrations of dexamethasone, serum and urine samples were analyzed by use of a competitive enzyme immunoassay.

Results

During the period of continued topical treatment, serum dexamethasone concentrations increased to between 0.10 and 0.49 ng/ml, then decreased below the limit of detection (0.06 ng/ml) within 24 hours after cessation of treatment. Dexamethasone also was detected in urine samples at concentrations of up to 0.98 ng/ml.

Conclusions

Repeated topical administration of dexamethasone ophthalmic ointment generated low, but detectable glucocorticoid concentrations in serum and urine.

Clinical Relevance

Because treatment of performance horses with dexamethasone is prohibited for most types of competitions and because enhanced glucocorticoid detection methods may result in positive test results, owners and trainers may wish to reconsider entering horses in competitions during periods of treatment with ophthalmic dexamethasone preparations. (Am J Vet Res 1999;60:571–576)
Anesthesia of horses with a combination of detomidine, zolazepam, tiletamine, and isoflurane immediately after strenuous treadmill exercise
Authors: Rankin David C. , Greene Stephen A. , Keegan Robert D. , Weil Ann B. , Schneider Robert K. , Bayly Warwick M.
Published: January 2024

Objectives

To evaluate effects of strenuous exercise in adult horses immediately before anesthesia and to determine whether prior exercise affects anesthesia induction, recovery, or both.

Animals

6 healthy Thoroughbreds in good condition and trained to run on a treadmill, each horse serving as its own control.

Procedure

Horses ran on a treadmill until fatigued, then were sedated immediately with detomidine hydrochloride and anesthetized with a zolazepam hydrochloride-tiletamine combination. Anesthesia was maintained with isoflurane in oxygen for another 90 minutes. Blood samples were taken before, during, and after exercise and during anesthesia.

Results

During exercise, changes in heart rate, core body temperature, plasma lactate concentration, arterial pH, and PaCO2 were significant. Plasma ionized calcium concentration was lower after exercise, compared with baseline values, and remained lower at 30 minutes of isoflurane anesthesia. Compared with baseline values, plasma chloride concentration decreased significantly during anesthesia after exercise. Cardiac output during anesthesia was significantly lower than that during preexercise, but significant differences between experimental and control periods were not observed. Arterial blood pressure during anesthesia was significantly lower than that during preexercise and initially was maintained better during isoflurane anesthesia after exercise. Cardiac output and blood pressure values were clinically acceptable throughout anesthesia.

Conclusion

Administration of detomidine hydrochloride followed by zolazepam hydrochloride-tiletamine appeared to be safe and effective for sedation and anesthesia of horses that had just completed strenuous exercise.

Clinical Relevance

Anesthetic given in accordance with this protocol can be used to anesthetize horses that are injured during athletic competition to assess injuries, facilitate first aid, and possibly allow salvage of injured horses. (Am J Vet Res 1999;60:743–748)
Doppler echocardiographic study of left and right ventricular function during dobutamine stress testing in conscious healthy dogs
Authors: Entee Kathleen Mc , Clercx Cécile , Amory Hélène , Michaux Charles , Dardenne Jean-Jacques , Soyeur Daniel , Henroteaux Marc
Published: January 2024

Objective

To evaluate left and right ventricular filling and ejection performances by use of Doppler echocardiography in healthy, conscious dogs submitted to dobutamine stress testing.

Animals

10 unsedated, healthy adult Beagles.

Procedure

Doppler echocardiography was performed during cardiac stress testing on each dog twice at 24-hour intervals. Dobutamine was infused in 10 µg/kg of body weight/min incremental dosages, from 12.5 to 42.5 µg/kg/min. Duration of each step was 15 minutes. Doppler measurements were recorded at baseline and at each stage of dobutamine infusion, whereas aortic diameter was measured at baseline and at peak dosage by use of two-dimensional echocardiography.

Results

Dobutamine infusion induced a significant increase in velocity time integrals and in peak flow velocities at the aortic, pulmonic, mitral, and tricuspid valves. Acceleration time-to-deceleration time ratio at the aortic wave also was increased significantly. On the other hand, ejection time, acceleration time, and deceleration time at the aortic and pulmonic valves and peak flow velocity of the E wave-to-peak flow velocity of the A wave ratio at the mitral and tricuspid valves decreased significantly during the test. The acceleration time-to-deceleration time ratio at the pulmonic wave was unchanged. A significant, progressive increase in cardiac index also was observed during dobutamine infusion, with a maximal increase of 104% from baseline. This was mediated initially by an increase in stroke index and, at higher dosages, by an increase in heart rate.

Conclusions and Clinical Relevance

Doppler echocardiography performed during dobutamine stress testing may be a reliable method of assessing myocardial function in dogs with cardiovascular disease. (Am J Vet Res 1999;60:865–871)
Pharmacokinetics and therapeutic efficacy of rimantadine in horses experimentally infected with influenza virus A2
Authors: Rees William A. , Harkins J. Daniel , Lu Ming , Holland Robert E. , Lehner Andreas F. , Tobin Thomas , Chambers Thomas M.
Published: January 2024

Objective

To determine pharmacokinetics of single and multiple doses of rimantadine hydrochloride in horses and to evaluate prophylactic efficacy of rimantadine in influenza virus-infected horses.

Animals

5 clinically normal horses and 8 horses seronegative to influenza A.

Procedure

Horses were given rimantadine (7 mg/kg of body weight, IV, once; 15 mg/kg, PO, once; 30 mg/kg, PO, once; and 30 mg/kg, PO, q 12 h for 4 days) to determine disposition kinetics. Efficacy in induced infections was determined in horses seronegative to influenza virus A2. Rimantadine was administered (30 mg/kg, PO, q 12 h for 7 days) beginning 12 hours before challenge-exposure to the virus.

Results

Estimated mean peak plasma concentration of rimantadine after IV administration was 2.0 µg/ml, volume of distribution (mean ± SD) at steady-state (VdSS) was 7.1 ± 1.7 L/kg, plasma clearance after IV administration was 51 ± 7 ml/min/kg, and β-phase halflife was 2.0 ± 0.4 hours. Oral administration of 15 mg of rimantadine/kg yielded peak plasma concentrations of < 50 ng/ml after 3 hours; a single oral administration of 30 mg/kg yielded mean peak plasma concentrations of 500 ng/ml with mean bioavailability (F) of 25%, β-phase half-life of 2.2 ± 0.3 hours, and clearance of 340 ± 255 ml/min/kg. Multiple doses of rimantadine provided steady-state concentrations in plasma with peak and trough concentrations (mean ± SEM) of 811 ± 97 and 161 ± 12 ng/ml, respectively. Rimantadine used prophylactically for induced influenza virus A2 infection was associated with significant decreases in rectal temperature and lung sounds.

Conclusions and Clinical Relevance

Oral administration of rimantadine to horses can safely ameliorate clinical signs of influenza virus infection. (Am J Vet Med 1999:60:888–894)
Alterations in bone remodeling in the femur after medullary reaming and cemented hip arthroplasty in dogs
Authors: VanEnkevort Bruce A. , Markel Mark D. , Manley Paul A.
Published: January 2024

Objective

To determine whether medullary reaming alone, or followed by cemented hemiarthroplasty, influenced porosity, vascularity, and new bone formation in the proximal portion of the femur in dogs.

Animals

12 adult mixed-breed dogs.

Procedure

Unilateral femoral head and neck excisions were performed, followed by femoral medullary reaming in 6 dogs and femoral medullary reaming and cemented hemiarthroplasty in 6 dogs; the contralateral femur was used as a control. All dogs were euthanatized 28 days after surgery, and femurs were harvested. Vascularity, porosity, and new bone formation were quantified for all femurs of dogs from both groups at 3 proximal-to-distal levels, 3 regions (periosteal, midcortical, and endosteal), and 4 quadrants (cranial, caudal, medial, and lateral) of the femur.

Results

Medullary reamed and cemented hemiarthroplasty femurs had significant increases in vascularity and porosity at all levels and in new bone formation at levels 2 and 3. Porosity was increased significantly in the periosteal region of the cemented hemiarthroplasty (9.7 ± 0.7%), compared with control (2.3 ± 0.2%) and medullary reamed (8.4 ± 0.7%) femurs. Porosity was increased in the caudal and medial quadrants in the medullary reamed and cemented hemiarthroplasty femurs; vascularity results were similar.

Conclusion

Increased porosity, vascularity, and new bone formation in reamed and cemented hemiarthroplasty-treated femurs supports the theory that surgical trauma associated with medullary reaming is an important factor in early cortical bone loss after hip arthroplasty.

Clinical Relevance

Femoral remodeling associated with reaming and broaching is appreciable but may be only a temporary response, whereas other factors may be responsible for chronic cortical bone loss. (Am J Vet Res 1999;60:922–928)
Response of embryonic chicken lymphocytes to in ovo exposure to lymphotropic viruses
Authors: St. Hill Catherine A. , Sharma Jagdev M.
Published: January 2024

Objective

To examine effects of virus exposure on embryonic lymphoid organ structure, apoptosis, and lymphoid cell subpopulations.

Animals

Eggs of specific pathogen free (SPF) White Leghorn chickens at embryonation day (ED) 17.

Procedures

Eggs were inoculated with 2,000 plaque-forming units (PFU) of serotype 1 herpesvirus (Marek’s disease virus [MDV 1]), 2,000 PFU of herpesvirus of turkeys (MDV 3), or 1,000 embryo infectious doses (EID50) of infectious bursal disease virus (IBDV). On post-inoculation days (PID) 3 and 5, lymphoid organ to body weight ratios were determined, and bursa of Fabricius, thymus, and spleen were evaluated for lesions and apoptosis. Proportions of lymphoid cell subpopulations of PID-3 chicken embryos and 7- to 10-day-old chicks were quantitated by flow cytometry.

Results

Lymphoid organ weights were similar in virus-free, MDV 1, and IBDV groups. Embryos inoculated with 2,000 PFU MDV 3/egg had lower bursal weights than virus-free controls. In a repeated trial, MDV 3 (1,000 PFU to 4,000 PFU) did not reduce bursal weights among groups. Histologic changes were seen in bursae after MDV 1 and IBDV inoculation. Apoptosis was greater in bursae of MDV 1-infected embryos than controls. Lymphoid cell subpopulations were similar among all groups with the exception of CD8+ and IgM+ cells in spleens of IBDV-infected 10-day-old chicks.

Conclusions and Clinical Relevance

Infection with pathogenic strains of MDV 1 and IBDV did not alter lymphocyte subpopulations in embryos or cause complete destruction of lymphoid organs. Changes in lymphoid cell subpopulations exposed as embryos to IBDV were seen only after hatching. (Am J Vet Res 1999;60:937–941)
Effects of inhalation of dust and endotoxin on respiratory tracts of pigs
Authors: Urbain Bruno , Mast Jan , Beerens Dominique , N’Guyen T. Quyen , Goddeeris Bruno , Ansay Michel , Gustin Pascal
Published: January 2024

Objective

To assess the effects of inhalation of feed flour dust and dustborne endotoxin on respiratory tracts of pigs.

Animals

29 healthy Belgian Landrace pigs.

Procedure

Pigs housed in an environmental chamber were exposed for 6 days to feed flour dust (1 to 15 mg/m3) and dustborne endotoxins (50 to 2,500 ng/m3). Effects were evaluated by measuring albumin concentration, lactate dehydrogenase (LDH) activity, cell composition of nasal lavage (NL) and broncho-alveolar lavage (BAL) fluids and blood, and percentages of CD4+ and CD8+ T lymphocytes in blood and lavage fluids. Dustborne endotoxin was obtained by mixing endotoxins from Escherichia coli (serotype O127:B8) with feed flour before spraying the flour in the environmental chamber.

Results

Exposure did not affect cell composition of NL fluid or blood. Total cell counts of BAL fluids were increased in all groups exposed to dust. Macrophage counts were increased in pigs exposed to inhalable dust concentrations as low as 4.4 mg/m3, and lymphocyte counts were increased in groups exposed to high dust concentrations. Percentages of CD4+ and CD8+ T lymphocytes in blood and lavage fluids were unchanged. In all dust-exposed groups, albumin content of BAL fluid was increased, whereas LDH activity was unaffected. Macrophage and lymphocyte infiltration and edema in the bronchi were identified by light microscopy. Effects attributable to E coli endotoxin exposure were not identified.

Conclusions

Inhalation of feed flour dust did not affect nasal mucosa but did induce bronchial airway inflammation. Dustborne endotoxins did not have effects attributable to endotoxin alone. (Am J Vet Res 1999;60:1055-1060)
Hemodynamic and metabolic alterations associated with intravenous infusion of a combination of adenosine triphosphate and magnesium chloride in conscious horses
Authors: Tetens Joanne , Bueno Aloisio C. , Cornick-Seahorn Janyce L. , Hosgood Giselle , Eades Susan C. , Moore Rustin M.
Published: January 2024

Objective

To determine hemodynamic and metabolic effects of IV infusion of ATP-MgCl2 combination and maximal safe IV infusion rate in conscious horses.

Animals

6 adult female horses.

Procedure

All horses received an IV infusion of ATP-MgCl2 combination, beginning at a rate of 0.05 mg of ATP/kg of body weight/min, which was increased by 0.05 mg/kg/min increments at 10-minute intervals until a rate of 1.0 mg/kg/min was achieved. Data were collected prior to the start of the infusion, at the end of each infusion rate, and at 15-minute intervals for the next hour after discontinuation of the infusion. Measured or calculated hemodynamic variables included cardiac output, cardiac index, heart rate, stroke volume, systemic and pulmonary arterial pressures, and systemic and pulmonary vascular resistances. Arterial blood gas tensions, CBC, plasma biochemical profiles, urine volume and specific gravity, and selected clinical signs of disease also were evaluated.

Results

Intravenous infusion of ATP-MgCl2 significantly increased cardiac output, decreased systemic vascular resistance, and caused mild pulmonary hypertension. Magnitude of the hemodynamic alterations was dependent on rate of infusion. Maximal safe infusion rate for these horses was 0.3 mg/kg/min. All horses became lethargic, and their appetites diminished during the infusion; 5 horses had mild signs of abdominal discomfort. Flank sweating was observed in all horses as infusion rate increased. Urine volume and specific gravity and hematologic, biochemical, and arterial blood gas alterations were detected during and after infusion.

Conclusions and Clinical Relevance

Intravenous administration of ATP-MgCl2 in healthy, conscious, adult horses caused various metabolic and hemodynamic alterations that were without appreciable detrimental effects. (Am J Vet Res 1999;60:1140–1147)
Concentration of volatile fatty acids in digesta samples obtained from healthy cows and cows with cecal dilatation or dislocation
Authors: Abegg Richard , Eicher Richard , Lis Jan , Lischer Christoph J. , Scholtysik Günter , Steiner Adrian
Published: January 2024

Objective

To compare concentrations of acetic, propionic, butyric, and i- and n-valerianic acids in digesta samples obtained from the rumen, cecum, proximal loop of the ascending colon (PLAC), and rectum of healthy cows and cows with cecal dilatation or dislocation (CDD).

Animals

20 cows with CDD and 20 healthy cows.

Procedure

Samples were collected from all sites during surgical correction of CDD and also from the rectum 1, 2, and 3 days after surgery (group CDD). Samples from healthy (control) cows, matched on the basis of diet and milk yield, were obtained at a slaughterhouse. Concentrations of volatile fatty acids (VFA) were analyzed by use of gas chromatography. Absolute concentration of each VFA was additionally corrected for pH to allow calculation of the concentration of undissociated VFA.

Results

Absolute concentration and concentration of the undissociated form of all analyzed VFA were significantly increased in samples collected from the cecum and PLAC of cows in group CDD, compared with concentrations for control cows. Within 3 days after surgery, significant decreases of the absolute concentration of butyric, i- and n-valerianic acids, and undissociated i- and n-valerianic acids were evident in samples obtained from the rectum of group-CDD cows. Concentrations of VFA in samples obtained from the rectum during surgery correlated with corresponding VFA concentrations in samples obtained from the PLAC.

Conclusions

Concentrations of VFA are increased in the cecum and PLAC of cows with CDD. However, the role of increased concentrations of VFA in the etiopathogenesis of CDD is unknown. (Am J Vet Res 1999;60:1540–1545)
Epidemiologic analysis of factors influencing exertional rhabdomyolysis in Thoroughbreds
Authors: MacLeay Jennifer M. , Sorum Sandy A. , Valberg Stephanie J. , Marsh Will E. , Sorum Mike D.
Published: January 2024

Objective

To determine incidence, effect on performance, and management practices associated with exertional rhabdomyolysis (ER) in Thoroughbreds.

Sample Population

Medical records for 984 Thoroughbreds and a survey of trainers of horses with and without ER.

Procedures

Medical records for 984 Thoroughbreds stabled at a midwestern racetrack were examined to determine the incidence of ER during the 1995 racing season. A retrospective questionnaire was administered to trainers to determine management practices associated with ER in 59 Thoroughbreds with ER and 47 control Thoroughbreds in training. Multiple logistic regression was used to determine management factors associated with ER.

Results

ER affected 48 of 984 (4.9%) Thoroughbreds. Two-year-old females were most frequently affected, and 36 of 96 (37.5%) trainers had ≥ 1 horse with ER. Horses with ER were more likely not to race during the racing season, compared with control horses. For horses that raced, differences were not found with respect to racing performance between ER and control horses. Exertional rhambdomyolysis developed frequently in susceptible horses that had ≥ 1 day of rest prior to exercise and that galloped during exercise. Horses with ER were commonly fed > 4.5 kg of grain daily. Nervous and extremely nervous horses were 5.4 times more likely, and horses with some form of lameness were 4.2 times more likely, to have ER.

Conclusions and Clinical Relevance

Exertional rhabdomyolysis is common in Thoroughbreds, and ER can be affected by temperament, sex, age, diet, exercise routines, and lameness. Management that minimizes excitability, particularly when tailored to each horse, may be most effective for controlling ER. (Am J Vet Res 1999;60:1562–1566)
Dietary Taurine Improves The Growth Performance, Health Status and Liver Histopathology of Meagre (Argyrosomus Regius) Fed A Reduced Fish Meal Diet
Authors: Güroy Derya , Karadal Onur , Güroy Betül , Emre Yılmaz , Emre Nesrin , Eraslan Durali , Yalım Fatma Banu , Mantoğlu Serhan , Demir Abdullah
Published: January 2024

Research has focused on alternative plant materials or additives that can be used instead of fish meal due to limited stocks and increased feed prices, although it is important for carnivorous fish species. Taurine is a functional amino acid supplemented to low fish meal diets to improve the growth performance of fish. In this study, eight experimental diets with 0%, 0.5%, 1% and 2% ratios of taurine supplemented (T0, T0.5, T1 and T2) high (HFM) and low fish meal (LFM) diets were prepared (defined as HFMT0, HFMT0.5, HFMT1, HFMT2, LFMT0, LFMT0.5, LFMT1 and LFMT2). The experiment was carried out in twenty-four 400 L rectangular fiberglass tanks conducted in a marine water system, and fish (initial mean weight of 23.5 g) were stocked in each tank. The nutrition trial was carried out for 90 days with three replicates. Meagre fed with the HFMT1 diet had a higher final mean weight (FMW) and specific growth rate (SGR) than fish fed with HFMT0 and all LFM diets. Including taurine in all LFM diets also enhanced growth performance. The FMW and SGR of fish fed the LFMT0.5 diet were similar when compared to HFMT0 (P>0.05) and increased compared to that of other LFM diets with taurine (P<0.05). Meagre fed the LFM0.5 diet had a lower feed conversion rate (FCR) than those provided for all HFM diets, although there was no significant difference between treatments. Dietary taurine has decreased the hepatosomatic index (HSI), viscerosomatic index (VSI) and total ammonia-nitrogen excretion (TAN), irrespective of taurine and fish meal levels. Including dietary taurine at both fish meal levels enhances the number of red blood cells (RBC) and whole-body amino acids of meagre. The most remarkable conclusion of this study is the inclusion of taurine in low fish meal diets improved growth performance and profitability in meagre, and the level of 0.5% has been recommended.
Pesticides and Heavy Metal Toxicity in Fish and Possible Remediation – A Review
Authors: Ghafarifarsani Hamed , Fazle Rohani Md. , Raeeszadeh Mahdieh , Ahani Saman , Yousefi Morteza , Talebi Maedeh , Sazzad Hossain Md.
Published: January 2024

Pesticides and heavy metals are considered as potent contaminants in aquatic environment. Both contaminants are sourced into the aquatic ecosystems by various types of anthropogenic as well as natural practices. Such types of aquatic contamination drastically affect the normal activity of associated living organisms particularly fish. Both the pesticides and heavy metals toxicity cause several negative effects on fish growth, physiology, immune response, reproduction, embryonic and larval development as well as different histopathology of major organs including fish gill, kidney, liver, gonads, and intestine. Besides, the consumption of contaminated fish poses a serious health concern to associated consumers. Considering these serious issues, the current review is designed to investigate the toxic effects of pesticides and heavy metals on different aspects of fishes along with their possible sources, major types, and mode of action as well as role of medicinal herbs to mitigate their toxicity.
Functional jaw orthopaedics - does it realize our expectations?
Authors: Rudolph Walter F.T.
Published: January 2024

Functional orthopaedics fulfills treatment expectations whenever the therapeutic devices are used within the limits of their applications. Especially successful has been the application of modified, skeletalized (reduced) activators in the deciduous and the mixed dentition, and the use of functional appliances in the early permanent dentition in Angle Classes I, II, and III malocclusions where primary functional causes exist. Whilst the inter-arch expansion obtained with functional appliances may average more than 3-4 mm and provide good treatment responses, the single tooth movements, including rotations, are more certainly and more effectively carried out with fixed appliances. In the latter types of cases, combined therapy, consisting of pre-treatment with an active fixed appliance and subsequent treatment with the activator, may be more successful.
A study of bilabial lip pressure in a normal population
Authors: Newman Denis G. , Barnes Anthony , Newman Jacqueline
Published: January 2024

Values for bilabial lip pressure on 1,417 children ranging in age from 5 to 18 years of age are presented. The use of bilabial lip pressure values as a tool in monitoring speech production of children with neuromuscular disease, articulation disorders and cleft lip is discussed. Variations with age, sex, height, weight and malocclusion type are presented with mean average values being 5 to 20% larger than the maximum recordings.

In males, the mean values rose by approximately 5% between the ages of 5 and 7 years, remained fairly constant up to age 11, between 11 and 14 years the mean values more than trebled after which they gradually declined with males aged 18 and over having a mean of approximately 75% of the peak at 14 years. In females, the mean values were similar to males up to age 11 years and also demonstrated a sharp increase thereafter peaking at 14 years. The peak for females was, however, only 60% of the corresponding male value, having doubled in the 11-14 year period in contrast to the males who showed a three fold increase. Females exhibited a decline in mean values afte 14 years of a similar relative magnitude to that of the males.

Correlation with height and weight are presented but regression analysis showed that these factors had little additional influence over and above those of subject age.
An alternative view of the temporomandibular joint pain-dysfunction syndrome
Authors: Reade Peter C.
Published: January 2024

An alternative view of the aetiology and treatment of TMJPDS has been presented emphasising the part that a sprain of the temporomandibular joint(s) plays in initiating the condition and the subsequent influence of preexisting occlusal and other factors in maintaining the painful problem rather than allowing the sprain to resolve spontaneously. The rationale for the specific occlusal splint therapy described has been briefly discussed.
Timing of orthodontic treatment: early or late — does it matter?
Authors: Grave Keith C.
Published: January 2024

The objective of this paper is to clarify the perplexing question of when to start treatment. Timing of orthodontic treatment should focus on individual maturation and family patterns. It will simplify treatment, and minimize co-operation problems, and as a consequence it will keep the orthodontist and his patient happy.
Orthodontic bonding – a national survey: Part I – Eesolts and Inferences
Authors: Russell Mark L. , Beech Derrick B. , Brown David
Published: January 2024

A survey of orthodontists in Australia was conducted in 1984. Of 325 questionnaires, there were 203 (65%) respondents. Over 90% had been bonding for three or more years, with a clear preference for composites over acrylic, for smaller mesh bases over larger bases, and for anteriors over full bonding although a significant number include premolars. It would seem that one third had not changed bonding products, but those who did change gave an interesting assortment of reasons for their change. A mean estimated failure rate of 5.6% is close to that reported in other surveys. Plastic brackets have gone out of favour.

A future article will look at correlations between such things as bonding technique, adhesive type and failure rates; recycling and “black spot” lesions.