bluuebunny/crossref_metadata_2025 huggingface dataset:
Induction of dual infections in newborn and three-week-old pigs by use of two plaque size variants of porcine reproductive and respiratory syndrome virus
Authors: Park Bong K. , Joo Han S.
Published: January 2024

Objective

To determine whether pigs can be dually infected with different plaque variants of porcine reproductive and respiratory syndrome virus (PRRSV).

Animals

2 pregnant sows, 20 newborn pigs, and 20 three-week-old pigs.

Procedure

The 2 late-term pregnant sows were inoculated with the PRRSV small-plaque variant MN-Hs, and their pigs were challenge exposed at 7 days of age with the PRRSV large-plaque variant MN-HI. In addition, twelve 3-week-old pigs were inoculated with MN-Hs virus. Two groups of the pigs were challenge exposed with MN-HI virus at 14 and 42 days after initial inoculation. Virus was isolated from the pigs at various intervals, plaque sizes were examined, and serologic testing was performed.

Results

From the 2 groups of ten 7-day-old pigs, small-plaque PRRSV was isolated from 8 and 10 pigs. After subsequent challenge exposure, dual infections were diagnosed in 3 of 10 inoculated and 4 of 10 contact control pigs. In 3-week-old pigs infected with MN-Hs virus, dual infections were documented in 2 of 6 pigs when challenge exposed 14 days after initial infection. Virus was not isolated from sera of another 6 pigs challenge exposed 42 days after initial infection. Serum neutralization antibody was detected in all 6 pigs at challenge exposure.

Conclusions

Dual infections were documented in viremic newborn pigs and 3-week-old pigs, using 2 plaque variants of PRRSV. (Am J Vet Res 1997;58: 257–259)
Use of nested polymerase chain reaction to identify feline herpesvirus in ocular tissue from clinically normal cats and cats with corneal sequestra or conjunctivitis
Authors: Stiles Jean , McDermott Michelle , Bigsby Deborah , Willis Michelle , Martin Charles , Roberts Wayne , Greene Craig
Published: January 2024

Objective

To use a nested polymerase chain reaction (PCR) to detect feline herpesvirus (FHV-1) DNA in conjunctiva or cornea from clinically normal cats and cats with conjunctivitis or corneal sequestra.

Samples

Conjunctival snip biopsy specimens from 50 cats with conjunctivitis and 50 clinically normal cats; 28 keratectomy specimens from 26 cats with sequestra, and 13 specimens from clinically normal cats.

Procedure

Tissue specimens were digested, and FHV-1 DNA was amplified, using a double round of PCR. Products were visualized by use of agarose gel electrophoresis.

Results

Polymerase chain reaction was positive in 27 of 50 (54%) conjunctival specimens from cats with conjunctivitis and 6 of 50 (12%) specimens from clinically normal cats. Difference in the results between cats with conjunctivitis and clinically normal cats was statistically significant. Polymerase chain reaction was positive in 5 of 28 (18%) corneal specimens from cats with sequestra and 6 of 13 (46%) clinically normal cats. Distribution of positive results between clinically normal cats and those with sequestra was not significant.

Conclusion

Cats with conjunctivitis were more likely to have a positive PCR result than were clinically normal cats, making it likely that FHV-1 was associated with the disease state. Herpesvirus DNA could not be detected in most corneas from cats with sequestra.

Clinical Relevance

Polymerase chain reaction is a useful clinical test for identifying FHV-1 DNA in cats with conjunctivitis, yielding greater sensitivity over that of currently available tests. Herpesvirus may be less of a cause of corneal sequestration in the commonly affected breeds, Himalayan and Persian, than other factors, such as lagophthalmos or corneal metabolic defects. (Am J Vet Res 1997;58:338–342)
Use of Rhodococcus equi virulence-associated protein for immunization of foals against R equi pneumonia
Authors: Prescott J. F. , Nicholson V. M. , Patterson M. C. , Meleiro M. C. Zandona , Araujo A. Caterino de , Yager J. A. , Holmes M. A.
Published: January 2024

Objective

To evaluate use of the virulence-associated protein of Rhodococcus equi in immunizing foals against R equi pneumonia.

Animals

Eight (experimental group) and 6 (controls) mares with their foals.

Procedure

Virulence-associated protein extracted from R equi was used to prepare an acetone-precipitated, Triton ×-extracted (APTX) antigen. After determination of the efficacy of passive immunization, in untreated foals or in foals given plasma from a horse vaccinated with APTX antigen or from a nonvaccinated horse, a field trial was done to evaluate the efficacy of vaccination of 8 mares, twice with APTX before parturition, and of their foals at ages 3 and 5 weeks; 6 mares and their foals served as unvaccinated controls. All 2-day-old foals were given plasma from local donor horses inoculated with a locally produced bacterin. Serum opsonizing activity produced by vaccination with APTX was determined. Passively immunized foals were challenge exposed with an aerosol of virulent R equi. Foals of the field trial were exposed to enzootic R equi infection.

Results

Inoculation with APTX resulted in high IgG antibody titers with opsonizing activity. Passive immunization of foals with plasma from an immunized horse enhanced bacterial clearance from the lungs, compared with that in foals not given plasma or given plasma without APTX antibodies. Vaccination of mares and foals exposed to natural infection resulted in development of R equi pneumonia in 4 of 8 vaccinated foals, but in only 1 of 6 unvaccinated foals,.

Conclusions

Vaccination with APTX antigen led to high-titer, opsonizing antibody. Plasma from a vaccinated horse appeared to enhance clearance of R equi from the lungs of foals. Paradoxically, vaccination of mares and their foals with APTX antigen did not protect foals and may have enhanced R equi pneumonia in the foals. (Am J Vet Res 1997;58:356-359)
Changes in nutrient and protein composition of cat milk during lactation
Authors: Adkins Yuriko , Zicker Steven C. , Lepine Allan , Lönnerdal Bo
Published: January 2024

Objective

To evaluate changes in the nutrient and protein composition of cat milk during lactation.

Animals

12 lactating domestic shorthair cats.

Procedure

Milk samples collected on days 1, 3, 7, 14, 28, and 42 after parturition were analyzed for concentrations of nitrogen, nonprotein nitrogen, casein, whey proteins, amino acids, total lipids, lactose, citrate, minerals, and trace elements. Individual milk proteins (caseins and whey proteins) were analyzed by use of polyacrylamide gradient gel electrophoresis.

Results

True protein concentration ranged from 6.3 to 8.6% and was as high in mature milk as in colostrum. Nonprotein nitrogen as a portion of total N was constant (approx 8%), as was the whey-to-casein ratio (approx 50:50). Total lipid concentration was high (9.3%) in colostrum, rapidly decreased, then increased to 9% in mature milk. Lactose concentration was constant at 4%. Milk calcium, iron, and copper concentrations increased markedly during lactation, and magnesium and zinc values remained constant. Colostrum and early milk had a low Ca-to-P ratio of 0.4:0.9. Although calcium concentration increased with time, phosphate concentration also increased so that the Ca-to-P ratio remained constant in mature milk at 1.0: 1.2. The major whey proteins had molecular weights of approximately 14,000, 19,000, 40,000 and 80,000. The 80,000 protein (possibly lactoferrin) decreased in concentration during lactation. Two major casein subunits of approximately 28,000 and 33,000 were found, and both increased during early lactation.

Conclusions

Nutrient composition of cat milk and, thus, provision of nutrients to nursing kittens changes over time. (Am J Vet Res 1997;58:370-375)
Prophylaxis of respiratory distress syndrome in premature calves by administration of dexamethasone or a prostaglandin F2α analogue to their dams before parturition
Authors: Zaremba Wolfgang , Grunert Eberhard , Aurich Jörg E.
Published: January 2024

Objective

To investigate effects of preterm induction of calving by administration of flumethasone and dinoprost on the lecithin-to-sphingomyelin ratio in amniotic fluid and on neonatal respiratory distress after birth.

Animals

45 dairy cows and their newborn calves.

Procedure

Amniotic fluid from 45 cows was obtained and tested between days 258 and 270 of gestation. Cows were then given flumethasone (10 mg; n = 15), dinoprost (25 mg; n = 15), or saline solution (n = 15). Thirty hours later, left flank cesarean section was performed, amniotic fluid was collected, and the calf was delivered. Blood for determination of progesterone was withdrawn at amniotic fluid sample collections and before induction of calving. Blood for analysis of pH and base deficit was collected from calves during cesarean section and repeatedly after birth. Phospholipids in amniotic fluid were measured by thin-layer chromatography, and progesterone was determined by radioimmunoassay. Base deficit and pH were measured, using a blood gas analyzer.

Results

Before treatments, a corpus luteum was present in all cows and the lecithin-to-sphingomyelin ratio in amniotic fluid did not differ between groups. Thirty hours after injections of flumethasone and dinoprost, progesterone concentration had decreased (P < 0.05) and the lecithin-to-sphingomyelin ratio was significantly (P < 0.05) higher than values in controls. In calves delivered after flumethasone or dinoprost treatments, the degree of acidosis was significantly (P < 0.05) less than that in controls.

Conclusions

Flumethasone and dinoprost, given to pregnant cows, accelerate fetal lung maturation and improve respiratory function after birth. (Am J Vet Res 1997;58:404–407)
Effects of continuous venovenous hemofiltration on cardiopulmonary function in a porcine model of endotoxin-induced shock
Authors: Murphey E. D. , Fessler J. F. , Bottoms G. D. , Latshaw H. , Johnson M. , Mueller B. , Clark W. , Macias W.
Published: January 2024

Objective

To determine whether continuous venovenous hemofiltration, proposed to remove inflammatory mediators from circulation, would resolve cardiopulmonary derangements in a model of established endotoxic shock.

Animals

16 clinically normal pigs.

Procedure

Endotoxin was infused, IV, into anesthetized pigs for a total of 50 minutes. Thirty minutes after termination of the infusion period, extracorporeal circulation was initiated through a 50-kd diafilter, or past the filter without ultrafiltrate formation. Cardiac and respiratory variables were monitored for a period of 4 hours.

Results

Infusion of lipopolysaccharide resulted in a severe hypodynamic circulatory state, with significant decreases in mean arterial pressure and cardiac output concurrent with a significant increase in pulmonary arterial pressure. Hemofiltration was not associated with any correction of lipopolysaccharide-induced cardiopulmonary derangements.

Conclusions

Continuous venovenous hemofiltration, as used in this acute experiment, did not improve cardiopulmonary dysfunction during endotoxic shock.

Clinical Relevance

Continuous venovenous hemofiltration needs further investigation before it can be recommended as a clinically effective treatment. (Am J Vet Res 1997;58:408–413)
Effect of maturation and aging on the histomorphometric and biochemical characteristics of equine superficial digital flexor tendon
Authors: Gillis Carol , Pool Roy R. , Meagher D.M. , Stover Susan M. , Reiser Karen , Willits Neil
Published: January 2024

Objective

To assess tendon morphology and non-reducible crosslink concentration, and associations of these findings with horse age and previously reported mechanical and ultrasonographic findings.

Sample Population

Superficial digital flexor tendon samples were obtained from 23 horses aged 2 to 23 years. The tendons had undergone ultrasonography and were submitted to biomechanical testing in the physiologic range prior to sample acquisition.

Procedure

Samples were sectioned in a transverse plane; then dorsal, palmar, central, lateral, and medial regions were evaluated for fascicle cross-sectional area (CSA), septal width, and vessel density (the product of vessel numbers and vessel CSA per field). Contiguous samples were analyzed for collagen crosslinking.

Results

Central fascicles were significantly larger than fascicles in other tendon regions. Fascicle CSA decreased significantly with increasing age. Because total tendon CSA is unrelated to increasing age, fascicle numbers appeared to increase with increasing age. Regional or age effects on septal width were not found. There was no age or regional effect on vessel numbers, density, or fractional area.

Fascicle CSA was positively correlated with total tendon CSA; fascicle CSA was negatively correlated with elastic modulus. Hydroxypiridinium concentration tended to increase with increasing horse age; this effect was associated with a positive correlation between hydroxypiridinium values and elastic modulus.

Conclusions

Equine superficial digital flexor tendon undergoes an increase in structural organization and an increase in nonreducible crosslinks with maturation and aging. These changes are associated with an increase in elastic modulus. (Am J Vet Res 1997; 58:425–430)
Influence of two diets on pharmacokinetic parameters of allopurinol and oxypurinol in healthy Beagles
Authors: Bartges Joseph W. , Osborne Carl A. , Felice Lawrence J. , Koehler Lori A. , Ulrich Lisa K. , Bird Kathy A. , Chen Menglan
Published: January 2024

Objectives

To determine whether diet influences the metabolism of IV administered allopurinol in healthy dogs.

Animals

6 healthy female Beagles, 4.9 to 5.2 years old and weighing 9.6 to 11.5 kg.

Procedures

Allopurinol was administered IV (10 mg/kg) while dogs consumed a 10.4% protein (dry weight), casein-based diet or a 31.4% (dry weight), meat-based diet. After each dose, plasma samples were obtained at timed intervals, and concentrations of allopurinol and its active metabolite, oxypurinol, were determined by high-performance liquid chromatography. An iterative, nonlinear regression analytical program was used to determine the weighted leastsquares, best-fit curves for plasma allopurinol and oxypurinol concentration-time data. From these data, pharmacokinetic parameters were calculated.

Results

Pharmacokinetic parameters for allopurinol and oxypurinol were not different when comparing the effect of diet.

Conclusion

There is no influence of diet on pharmacokinetic parameters of allopurinol or oxypurinol.

Clinical Relevance

In contrast to observations in human beings, allopurinol metabolism is not influenced by diet. Therefore, formation of xanthine-containing calculi in dogs consuming a high-protein diet and receiving allopurinol is probably not attributable to alteration of allopurinol metabolism. (Am J Vet Res 1997;58:511–515)
Use of Doppler ultrasonography to evaluate renal arterial blood flow in horses
Authors: Hoffmann K. L. , Wood A. K. W. , Kirby A. C.
Published: January 2024

Objectives

To obtain Doppler ultrasonographic images of renal arteries in horses and to establish reference range values for systolic and diastolic renal arterial blood flow and resistive indices. Also to determine whether Doppler ultrasonography could be used in horses to detect changes in renal blood flow after IV administration of furosemide.

Animals

11 clinically normal adult horses.

Procedures

Pulsed-wave Doppler examinations were performed on arcuate arteries of 5 sedated horses. Continuous-wave Doppler examinations were performed on pyelorenal arteries in 7 nonsedated horses and were repeated in 6 horses after furosemide administration. Peak-systolic velocity (SV) and end-diastolic velocity (EDV) were measured and the resistive indices (RI) were calculated.

Results

Using pulse-wave Doppler ultrasonography in sedated horses, arcuate arteries were determined to have a SV of 0.406 ± 0.116 m/s (mean ± SD), EDV of 0.184 ± 0.057 m/s, and Rl of 0.549 ± 0.044. Using continuous-wave Doppler ultrasonography in nonsedated horses, pyelorenal arteries were determined to have SV of 1.047 ± 0.009 m/s, EDV of 0.510 ± 0.006 m/s, and Rl of 0.512 ± 0.004. Doppler waveforms from the arcuate and pyelorenal arteries had a low resistance flow pattern, characterized by a systolic peak followed by a continuous antegrade diastolic flow. After furosemide administration, the pyelorenal arterial velocities increased, but the RI remained unchanged.

Conclusions

Doppler ultrasonography may be used to record renal blood flow in horses and to detect changes following furosemide administration.

Clinical Relevance

Doppler ultrasonographic images may assist in the diagnosis of renal diseases that affect either blood flow or Doppler waveform. (Am J Vet Res 1997;58:697–701)
Modeling study of compensatory head movements in lame horses
Authors: Vorstenbosch M. A. T. M. , Buchner H. H. F. , Savelberg H. H. C. M. , Schamhardt H. C. , Barneveld A.
Published: January 2024

Objective

To study the role of head movements in lame horses.

Sample Population

11 Dutch Warmblood horses.

Procedure

A 2-segment 2-dimensional inverse dynamic model of trotting horses was developed: trunk and head/neck segment joined in a neck joint. Model input consisted of averaged segmental inertial properties and averaged kinematic data, taken from 11 horses, trotting on a treadmill (3.5 m/s) in 3 conditions of induced lameness: sound, mildly lame, and moderately lame. Dynamic and static effects were analyzed.

Results

Dynamic effects were found to be considerably larger than static effects. In the moderately lame condition, the maximal neck joint vertical force during the lame stance phase had a 27% decrease, compared with the sound situation. Neck joint sagittal torque and maximal vertical force on the trunk decreased by 31 and 13%, respectively. Load distribution between forelimb and hind limb indicated a relative load shift from the lame forelimb to the diagonal hind limb during the lame stance phase. The sound contralateral forelimb carried a higher load while the ipsilateral hind limb was unloaded.

Conclusion

It could be concluded that asymmetric head movements have a major role in lameness compensation, which can be explained by inertial interaction between trunk and head/neck segment. Static effects, such as caudad shifting of the body center of mass, are of minor importance.

Clinical Relevance

This report clarifies the mechanism of lameness compensation and the method of lameness diagnosis. (Am J Vet Res 1997;58:713–718)
Humoral response of dairy cattle to spirochetes isolated from papillomatous digital dermatitis lesions
Authors: Walker Richard L. , Read Deryck H. , Loretz Kathleen J. , Hird David W. , Berry Steven L.
Published: January 2024

Objective

To determine whether a humoral response against spirochetes isolated from papillomatous digital dermatitis (PDD) lesions is elicited in dairy cattle affected with PDD.

Sample Population

41 cattle with PDD from 8 dairies (study population) and 30 cattle from 2 dairies free of PDD (control population). Additionally evaluated were 32 cattle from a dairy with a past history of PDD but no current disease, and 52 cattle from a dairy with high prevalence of PDD, 25 with and 27 without detectable lesions.

Procedure

ELISA were used to evaluate the humoral response of all cattle to representative isolates from 2 groups of spirochetes of unknown species isolated from PDD lesions. Specificity of the response was evaluated, using immune sera prepared against each of the spirochetes, and by adsorption studies of immune and field sera. The potential for confounding by an antibody response to other spirochetes associated with diseases of cattle was assessed.

Results

The antibody response (specific) to both PDD spirochete groups of cows with PDD was significantly increased, compared with that of cows from PDD-free dairies. There was no association between antibody response to PDD-associated spirochetes and antibody response to other spirochetal diseases of cattle. None of the cattle from the dairy with previous history of PDD but without current disease were classified as test positive by either PDD ELISA. There was a significant (P < 0.01) difference in classification results for both PDD ELISA for cattle with PDD from the dairy with a high herd prevalence of PDD, compared with cattle without detectable disease from the same dairy.

Conclusions and Clinical Relevance

The humoral response in cattle with PDD lesions was significantly different from that in cattle without detectable lesions, thus providing additional information regarding the potential role of spirochetes isolated from PDD lesions in the etiopathogenesis of PDD. (Am J Vet Res 1997;58:744–748)
Relation between serologic response and pathologic findings in sheep with naturally acquired paratuberculosis
Authors: Pérez V. , Tellechea J. , Badiola J. J. , Gutiérrez M. , Marín J. F. García
Published: January 2024

Objective

To investigate the relation between lesions and serologic response in sheep with naturally acquired paratuberculosis and to evaluate the efficacy of agar gel immunodiffusion (AGID) and ELISA as diagnostic tests.

Animals

134 adult sheep, culled by the owner from flocks with history of severe chronic weight loss.

Procedure

Before euthanasia, blood samples were collected and serum was obtained. AGID and ELISA were performed, using a protoplasmic antigen of Mycobacterium paratuberculosis. Sensitivity and specificity of these techniques were evaluated, using histopathologic findings as a reference. Histologic studies were carried out focusing on specimens containing intestinal organized lymphoid tissue.

Results

Of the sheep examined, 46.3% had lesions that were classified in 5 categories, according to their location, extension, cellular types, and presence of acid-fast bacilli. Regarding serologic test results, 37.1% of sheep with lesions had a positive AGID result, and all sheep without lesions had negative results. However, ELISA positivity was slightly greater—48.4% of sheep with lesions; however, by use of ELISA, 11.1% of sheep without lesions had positive results.

Conclusion

A close relation between pathologic findings and serologic response was determined, especially between presence of acid-fast bacilli (potentially heavily shedding sheep) in the intestinal lesions and positivity to serologic tests, especially AGID.

Clinical Relevance

On the basis of these results, together with its high specificity, reliability, and the difficulty of fecal specimen culture in sheep, AGID is proposed as a useful tool for seeking evidence of paratuberculosis in live sheep, and therefore, is suggested as the basis for control programs in areas in which the disease is a serious threat to sheep production. (Am J Vet Res 1997;58:799–803)
Serum concentrations of zinc and copper in Bull Terriers with lethal acrodermatitis and tail-chasing behavior
Authors: Uchida Yoshiko , Moon-Fanelli Alice A. , Dodman Nicholas H. , Clegg Michael S. , Keen Carl L.
Published: January 2024

Objective

To establish similarities or differences in tissue concentrations of zinc, copper, and iron in Bull Terriers with lethal acrodermatitis (LAD) and tail-chasing behavior (TCB) and to confirm the suspicion that copper is involved in the etiopathogenesis of LAD.

Samples

Serum samples from 29 Bull Terriers (9 control dogs, 6 dogs with LAD, 14 dogs with TCB), and liver and kidney specimens from 2 dogs and 1 and 4 dogs with LAD or TCB, respectively.

Procedure

Serum, liver, and kidney mineral (zinc, copper, and iron) concentrations in Bull Terriers with LAD or TCB and in a group of control dogs were analyzed, using flame atomic absorption after wet ashing technique.

Results

Serum zinc and copper concentrations were lower (P < 0.05) in dogs with LAD, compared with values for control dogs and dogs with TCB. Liver zinc and copper concentrations were similar to serum values. Kidney zinc and copper concentrations were similar among the 3 groups. Serum, liver, and kidney iron concentrations had a wide range of variability within all 3 groups.

Conclusion

Copper deficiency is associated with LAD. The primary cause of LAD may be copper deficiency, with zinc involved secondarily, or combined zinc and copper deficiencies. The role of ion deficiency in TCB was not clarified.

Clinical Relevance

Serum zinc and copper concentrations should be determined when LAD is suspected. (Am J Vet Res 1997;58:808–810)
Protection of dogs against canine distemper by vaccination with a canarypox virus recombinant expressing canine distemper virus fusion and hemagglutinin glycoproteins
Authors: Pardo M. Camila , Bauman John E. , Mackowiak Marc
Published: January 2024

Objectives

To evaluate the safety and efficacy of a live canarypox virus recombinant-canine distemper virus (CDV) combination vaccine against virulent CDV challenge exposure, and to document lack of interference among the other modified-live virus (MLV) components.

Animals

33 specific-pathogen-free (SPF) Beagle pups (7 to 10 weeks old).

Procedure

A canarypox virus recombinant-CDV combination vaccine was tested for safety and efficacy along with MLV components (canine adenovirus type 2, canine coronavirus, canine parainfluenza virus, and canine parvovirus) in 26 SPF Beagle pups. The combination vaccine was rehydrated with either Leptospira canicola-L icterohaemorrhagiae combination bacterin (vaccine 1) or sterile diluent (vaccine 2). An additional group of 7 seronegative SPF pups received the control MLV components devoid of the combination vaccine (vaccine 3). Two vaccinations were administered 21 days apart, either IM or SC. The dose of the combination vaccine used to inoculate these pups was 40 times lower than the recommended commercial dose. At 21 days after the booster vaccination, all pups were challenge exposed with a virulent CDV strain, then were observed for 21 days to record morbidity and mortality.

Results

Adverse local or generalized reactions were not induced by vaccinations. All vaccinates seroconverted to CDV. Serum antibody titers to MLV components were not different, with or without inclusion of the combination vaccine. After challenge exposure, morbidity and mortality in vaccinates were 0% (0/26); in control dogs, values were 100% morbidity and 86% mortality (6/7). Brain impression smear slides made from all dogs that did not survive challenge exposure were CDV positive by use of a direct fluorescein isothiocyanate method.

Conclusions

The canarypox virus-CDV combination vaccine, administered SC or IM, is a safe product that elicits CDV seroconversion, does not interfere with other vaccine components, and protects vaccinated pups against virulent CDV challenge exposure. (Am J Vet Res 1997;58:833–836)
Overexpression of p53 tumor suppressor protein in spontaneously arising neoplasms of dogs
Authors: Gamblin Rance M. , Sagartz John E. , Couto C. Guillermo
Published: January 2024

Objective

To determine prevalence of p53 tumor suppressor protein overexpression in spontaneously arising tumors of dogs, using the CM-1 polyclonal antibody and immunohistochemical methods.

Design and Sample Population

Retrospective analysis was performed on archived, paraffin-embedded tumor tissue from dogs. A total of 226 tumors were evaluated, including tumors of epithelial, mesenchymal, and round cell origins.

Procedure

Overexpression of p53 was detected by indirect immunohistochemical methods, using the CM-1 rabbit anti-human p53 polyclonal primary antibody. Protein overexpression was determined by use of a grading system based on percentage of stained tumor nuclei.

Results

Nuclear overexpression of p53 was detected in most squamous cell carcinomas, nasal ade-nocarcinomas, and perianal gland adenocarcinomas. Hemangiopericytomas, transitional cell carcinomas, mammary adenocarcinomas, apocrine gland adenocarcinomas, intestinal adenocarcinomas, mast cell tumors, and cutaneous histiocytomas had low numbers of nuclei overexpressing p53. Remaining tumor types had intermediate p53 nuclear overexpression. Cytoplasmic staining was observed in some carcinomas, particularly intestinal adenocarcinomas.

Conclusions

Overexpression of p53 is common in spontaneously arising neoplasms of dogs.

Clinical Relevance

Prospective determination of p53 status in some tumor types may be as clinically useful in determining prognosis and predicting survival times for dogs with cancer as it is for human beings with cancer. (Am J Vet Res 1997;58:857–863)
Cardiopulmonary effects of sevoflurane, compared with halothane, enflurane, and isoflurane, in dogs
Authors: Mutoh Tatsushi , Nishimura Ryohei , Kim Hwi-Yool , Matsunaga Satoru , Sasaki Nobuo
Published: January 2024

Objective

To evaluate cardiopulmonary effects of sevoflurane (Sevo), compared with halothane (Hal), enflurane (Enf), and isoflurane (Iso).

Animals

24 healthy Beagles, randomly assigned to 4 groups of 6 dogs each.

Procedure

Dogs under spontaneous ventilation were anesthetized with Sevo, Hal, Enf, or Iso. After minimum alveolar concentration (MAC) of each anesthetic was determined, anesthesia was maintained at light (1 MAC), moderate surgical (1.5 MAC), and deep (2 MAC), stages and cardiopulmonary variables at conscious state (baseline) and each anesthesia stage were measured.

Results

In dogs of the Sevo group, heart rate increased significantly from the baseline value at all anesthesia stages. Systemic vascular resistance during Sevo anesthesia decreased gradually with increasing anesthesia stage, which was accompanied by dose-dependent decreases in systolic, mean, and diastolic arterial blood pressures. At 1.5 and 2 MAC Sevo, stroke index decreased slightly but significantly from the baseline value; however, cardiac index was unchanged because of the significant increase in heart rate. Respiratory rate decreased significantly at 2 MAC from that at 1 MAC Sevo. Tidal volume and dead space-to-tidal volume ratio were unchanged at all anesthesia stages of Sevo, resulting in significantly decreased expired and alveolar ventilation at 2 MAC, compared with values at 1 and 1.5 MAC Sevo. increased and pHa decreased significantly, depending on anesthesia stage; increased significantly from baseline values, and remained constant because of inhalation of 100% O2.

Conclusion

Cardiovascular effects of Sevo were greater than those of Hal, similar to those of Iso, and less than those of Enf. Respiratory effects of Sevo were similar to those of Iso at all anesthesia stages, greater than those of Hal at 2 MAC, and less than those of Enf at 1.5 and 2 MAC. Up to the moderate surgical anesthesia stage, Sevo can be used safely in dogs undergoing spontaneous ventilation. (Am J Vet Res 1997;58:885–890)
High resolution protein electrophoresis of equine cerebrospinal fluid
Authors: Furr Martin , Chickering William R. , Robertson John
Published: January 2024

Objective

To determine normal CSF electrophoresis patterns in horses, and to determine whether the electrophoretic scans from horses with cervical compression differ from those of neurologically normal horses.

Animals

32 horses assigned to 1 of 2 groups: neurologically normal (n = 18) or cervical compression (n = 14).

Procedure

CSF was collected from 18 neurologically normal horses referred to the Marion duPont Scott Equine Medical Center, and protein electrophoresis was performed to describe the normal equine CSF electrophoretogram. Results of CSF electrophoresis from 14 horses with cervical compression were then compared with results for the neurologically normal horses.

Results

Horses with cervical compression had decreased β-globulin fraction, and 1 or 2 prominent post-β2 peak(s). When the presence of post-β peaks was used as a diagnostic criterion for cervical compression, the test had sensitivity of 71.4% and specificity of 81.8%, The positive and negative predictive values were 83.3 and 69.2%, respectively.

Conclusion and Clinical Implications

Electrophoresis of CSF may be a useful diagnostic aid in evaluation of horses with neurologic disease. (Am J Vet Res 1997;58:939–941)
Variations in the mechanical properties of cartilage from the canine scapulohumeral joint
Authors: Korvick Donna , Athanasiou Kyriacos
Published: January 2024

Objective

To measure the intrinsic material properties of scapulohumeral joint cartilage in adult dogs and determine whether regional differences exist within or between the humeral and glenoid cartilages.

Samples

Paired shoulder joints from 7 clinically normal adult dogs.

Procedure

An automated indentation apparatus was used to obtain the intrinsic mechanical properties of the cartilage at 7 sites on each joint surface.

Results

Topographic variations in mechanical properties of the glenoid and humeral cartilages were observed. The largest aggregate modulus (HA) for the humerus was seen at the caudocentral site (0.92 MPa) and for the scapula was seen at the centrocenter site (0.84 MPa). The mean shear modulus (μ) of humeral cartilage (0.23 MPa) was significantly greater than that of the glenoid cartilage (0.19 MPa). The mean Poisson's ratio (ν) of humeral cartilage (0.24) was significantly smaller than that for the glenoid cartilage (0.29). Mean humeral cartilage aggregate modulus (0.71 MPa) was larger than the value for glenoid cartilage (0.67 MPa), but these differences were not significant. There were no significant differences in the compressive stiffness of the opposing cartilage in the canine scapulohumeral joint.

Conclusions

Differences in mechanical properties between opposing humeral and glenoid cartilages are not a cause of cartilage injury in the scapulohumeral joint of adult dogs. The mechanical properties of cartilage from young dogs with open physes and incomplete subchondral bone plates may be different from those of adult dogs. (Am J Vet Res 1997;58:949–953)
Assessment of current techniques for determining tracheal luminal stenosis in dogs
Authors: Huber Michael L. , Henderson Ralph A. , Finn-Bodner Sue , Macintire Douglass K. , Wright James C. , Hankes Gerald H.
Published: January 2024

Objective

To assess the accuracy of current antemortem and postmortem techniques for determining tracheal luminal stenosis.

Animals

15 dogs.

Procedure

Percentage of tracheal luminal stenosis (PTLS) was determined by 6 methods, using measurements obtained by radiography, tracheoscopy, and necropsy after selected tracheostomy techniques were performed. To calculate PTLS, dorsoventral tracheal diameter was measured from preoperative and postoperative lateral cervical radiographic views. Preoperative or normal tracheal segments adjacent to the stenotic area were used to obtain normal tracheal diameter measurements. Planimetrically determined cross-sectional area (CSA), obtained from pre- and postoperative tracheoscopic photographs, was used to calculate PTLS. The CSA of tracheal specimens obtained at necropsy was determined, using the formula for an ellipse. Percentage of luminal stenosis was calculated, using CSA of the stenotic site and of segments craniad and caudad to the site obtained at necropsy or at surgery. All methods were compared with the control method of planimetrically determined CSA of sections obtained at necropsy of the tracheostomy and segments craniad and caudad to the site.

Results

Correlation was poor for radiographic and tracheoscopic techniques (r = 0.146 to 0.458, P > 0.05) The formula for an ellipse accurately predicted PTLS when measurements obtained at surgery (r = 0.516, P = 0.049) or segments craniad and caudad (r = 0.853, P < 0.001) to the site were used.

Conclusion

Antemortem methods of assessing PTLS did not correlate with control planimetric methods. Methods using CSA determined by tracheal diameter were weakly correlated to control planimetric techniques.

Clinical Relevance

Accurate measurement of the degree of tracheal stenosis cannot be made in clinical patients using current techniques. (Am J Vet Res 1997;58:1051–1054)
Application of multiplex polymerase chain reaction for rapid identification of Campylobacter jejuni and C coli associated with reproductive failure
Authors: Wesley Irene V. , Sanderson Thomas P. , Larson David J. , Harmon Karen M. , Andrews John J. , Miskimins Dale W. , Zeman David H.
Published: January 2024

Objective

To evaluate a multiplex polymerase chain reaction (PCR) to distinguish Campylobacter jejuni from C coll as causes of reproductive failure.

Procedure

Review of clinical cases of reproductive failure attributed to C jejuni or C coli.

Results

A case of swine abortion was attributable to infection with C coli. The porcine abortion isolates were verified as C coli by restriction fragment length polymorphism and multiplex PCR. Cases of endometritis in a fox and in mink caused by C jejuni were reviewed, and isolates were confirmed as C jejuni by results of the multiplex PCR.

Conclusion

Multiplex PCR was useful in identifying C coli and C jejuni recovered from atypical cases of reproductive failure. Multiplex PCR in conjunction with conventional assays may be useful for verifying other unusual instances of campylobacteriosis. (Am J Vet Res 1997;58:1070–1075)
Clinical, morphologic, and biochemical characteristics of Chediak-Higashi syndrome in fifty-six Japanese Black cattle
Authors: Ogawa Hiroyuki , Tu Chien-Hsien , Kagamizono Hitoshi , Soki Kozo , Inoue Yuziro , Akatsuka Hiroto , Nagata Shun-ichi , Wada Takeru , Ikeya Masahisa , Makimura Susumu , Uchida Kazuyuki , Yamaguchi Ryozi , Otsuka Hiromitu
Published: January 2024

Objective

To characterize Chediak-Higashi syndrome (C-HS) in Japanese Black cattle.

Animals

56 of 200 cattle with a bleeding disorder and giant granules in leukocytes.

Procedure

Clinical observation, CBC, hemostatic screening test, platelet aggregometry, electron microscopy, platelet constituent analysis, and ophthalmoscopic examination were done.

Results

Affected Japanese Black cattle had increased bleeding tendency and abnormal granules in their leukocytes. Susceptibility to infection was not increased. Cutaneous albinism was evident in 6 newborn calves, but not in most affected cattle. In all affected cattle, the tapetal fundus was pale and the nontapetal fundus was almost devoid of pigment. By electron microscopy, a remarkable decrease in the number of dense granules in platelets was observed. Functionally, collagen-induced platelet aggregation was markedly reduced.

Conclusions

This bleeding disorder was diagnosed as C-HS. With regard to susceptibility to infection, albinism, and mortality, clinical manifestations of C-HS in Japanese Black cattle were moderate, compared with C-HS in human beings and Hereford cattle.

Clinical Relevance

Because an autosomal recessive mode of inheritance was documented and recessive homozygotes could be easily detected, C-HS in Japanese Black cattle can be controlled. (Am J Vet Res 1997;58:1221–1226)
Effect of postexercise carbohydrate supplementation on muscle glycogen repletion in trained sled dogs
Authors: Reynolds A. J. , Carey D. P. , Reinhart G. A. , Swenson R.A. , Kallfelz F. A.
Published: January 2024

Objective

To evaluate the effect of immediate postexercise carbohydrate supplementation on muscle glycogen (MG) repletion during the first 4 hours of recovery in sled dogs.

Animals

24 Alaskan Huskies.

Procedure

Dogs were assigned to 1 of 3 treatment groups, and a muscle biopsy specimen was obtained 1 hour before and immediately (group A) or 4 hours (groups B and C) after a 30-km run. Immediately after exercise, dogs in group A and group C were given water; dogs in group B were given a glucose polymer solution (1.5 g/kg of body weight) in water.

Results

At 4 hours after exercise, MG concentration was significantly greater in group-B than in group-C dogs; the value in group-C dogs was not different from the value in group-A dogs immediately after exercise. Assuming similar rates of glycogen depletion between treatment groups, during the first 4 hours of recovery, group-B dogs replaced 49% of the glycogen used during exercise. Plasma glucose concentration was significantly greater in group-B than in group-A and group-C dogs at 100 minutes after exercise.

Conclusions

Immediate postexercise carbohydrate supplementation in sled dogs leads to increased glucose concentration, which in turn promotes more rapid rate of MG repletion in the first 4 hours of recovery than is observed in dogs not given supplements.

Clinical Relevance

For dogs running in multiple heats on a single day or over several consecutive days, immediate postexercise carbohydrate supplementation may promote more rapid and complete recovery between bouts of exercise. (Am J Vet Res 1997;58:1252–1256)
Detection of antibodies to Aspergillus fumigatus in serum of horses with mycosis of the auditory tube diverticulum (guttural pouch)
Authors: Guillot Jacques , Sarfati Jacqueline , Ribot Xavier , Jensen Henrik E. , Latgé Jean-Paul
Published: January 2024

Objective

To detect antibodies against Aspergillus fumigatus antigens in serum samples from horses and to evaluate the relevance of this method as an alternative approach to the diagnosis of mycosis of the auditory tube diverticulum (guttural pouch mycosis [GPM]).

Animals

Twelve clinically normal horses (controls) and 12 horses with GPM diagnosed by endoscopic observation of characteristic mycotic plaques.

Procedure

Antibodies to A fumigatus antigens were detected in serum by use of an ELISA and immunoblot analysis with extracellular antigens.

Results

Antibodies against A fumigatus antigens were found in healthy and diseased horses. Titer of total Aspergillus antibodies was not diagnostic for GPM. In contrast, immunoblot analysis results indicated that 2 antigens of 22 and 26 kd were constantly recognized by sera from diseased horses.

Conclusions

Reactivity to 22- and 26-kd A fumigatus antigens, as measured by immunoblot analysis, seemed to be diagnostic for GPM in horses. (Am J Vet Res 1997;58:1364–1366)
Immunohistochemical diagnosis of pestivirus infection associated with bovine and ovine abortion and perinatal death
Authors: Thür B. , Hilbe M. , Strasser M. , Ehrensperger F.
Published: January 2024

Objective

To establish a reliable, rapid, economical method for detection of pestivirus infection in bovine and ovine fetuses and to examine participation of these viruses in abortions and neonatal mortality.

Animals

213 bovine and 31 ovine fetuses, as well as 36 newborn calves and 25 lambs, which had died within 3 days after birth, were tested for bovine viral diarrhea virus (BVDV) and border disease virus by use of different methods.

Procedure

Detection of BVDV in fetuses was performed by immunohistochemical methods, using a panel of monoclonal antibodies against pestivirus antigens on cryostat and paraffin sections and by virus isolation in cell culture; in some instances, an antigencapture ELISA was performed. Results of the various methods were compared.

Results

Sensitivity of BVDV detection by immunohistochemical methods and virus isolation in cell culture was equal; however, it decreased in association with autolysis. In autolytic fetuses, use of formalin-fixed, paraffin-embedded brain sections was the most favorable method. Antigen detection by ELISA was less sensitive.

Conclusions

Immunohistochemical analysis of cryostat sections of brain, skin, thyroid gland, abomasum, and placenta is a rapid, sensitive method for detecting pestiviruses in fetuses. In the presence of advanced autolysis, this method used on formalin-fixed, paraffin-embedded brain sections is recommended over the other described methods. (Am J Vet Res 1997;58:1371–1375)
Evaluation of platelet activation and platelet-neutrophil aggregates in ponies with alimentary laminitis
Authors: Weiss Douglas J. , Evanson Oral A. , McClenahan David , Fagliari José J. , Jenkins Katherine
Published: January 2024

Objectives

To determine whether platelets are hyperaggregable or form platelet-neutrophil aggregates during the prodromal stages of acute laminitis of ponies.

Animals

Healthy adult ponies: 8 experimental and 6 control.

Procedures

Acute laminitis was induced by oral administration of corn starch and wood flour to 8 ponies, and indices of platelet activation were evaluated. Blood samples were collected before and at 4, 8, 12, 24, 28, and 32 hours after carbohydrate administration, and PCV, total plasma protein concentration, platelet count, activated clotting time, whole blood recalcification time, spontaneous platelet aggregation, ex vivo platelet aggregation responses, and platelet-neutrophil aggregates were determined. When lameness was first detected, ponies were euthanatized and arteriography and histologic examination of hooves were performed.

Results

Carbohydrate overload was associated with hyperaggregability of platelets throughout the prodromal stages of laminitis and increased numbers of platelet-neutrophil aggregates. Reduction of blood supply to affected hooves was variable, and blood clots were found in 6 of 11 laminitis-affected hooves.

Conclusions

Platelets were hyperaggregable throughout the prodromal stages of carbohydrate-induced laminitis and formed platelet-neutrophil aggregates. Platelet-neutrophil aggregates may initiate or contribute to development of acute laminitis.

Clinical Relevance

Anti-platelet therapy may be useful for treatment of acute alimentary laminitis in horses. (Am J Vet Res 1997;58:1376–1380)
Cytogenetic alterations in eight mammary tumors and tumor-suppressor gene p53 mutation in one mammary tumor from dogs
Authors: Mayr Burkhard , Dressier Andrea , Reifinger Martin , Feil Christian
Published: January 2024

Objective

To identify mutations in canine mammary tumors.

Animals

10 tumor-bearing dogs.

Procedure

Culture of neoplastic cells originating from mammary tumors was performed, and trypsin-G banding was used for cytogenetic investigations. The same tumors were subjected to molecular genetic screening by use of DNA extraction, polymerase chain reaction, DNA elution, and DNA sequencing for ras oncogenes and the p53 tumor suppressor gene.

Results

A broad spectrum of chromosome aberrations was observed, including trisomies, reciprocal translocations, and structural and numerical X-chromosome alterations and deletions. Molecular genetic analysis revealed a tumor suppressor p53 gene mutation in codon 249 of exon 7 in one instance. Interestingly, analyzed mammary tumors were free of mutations in N-ras, K-ras and H-ras, exons 1 and 2.

Conclusions

Chromosome alterations are wide-spread in canine mammary tumors, but no ras family mutations were detected in tumors from these 10 dogs.

Clinical Relevance

Knowledge about chromosome, oncogene, and tumor suppressor gene damage could be helpful for diagnosis and prognosis of neoplastic diseases in dogs. (Am J Vet Res 1998;59:69–78)
Effects of propofol anesthesia on intradermally injected histamine phosphate in clinically normal dogs
Authors: Kennis Robert A. , Robertson Sheilah A. , Rosser Edmund J. , Hauptman Joseph G.
Published: January 2024

Objective

To compare skin test reactivity of ID injected histamine phosphate in clinically normal dogs that were physically restrained or anesthetized with propofol.

Animals

12 clinically normal adult dogs.

Procedure

Nonanesthetized dogs (group 1) were restrained and shaved on the right side of the thorax. A single injection of sterile buffered saline solution (negative control) and 5 serial dilutions of histamine phosphate (0.05 ml each) were injected ID. Wheal size was measured after 15 minutes. Propofol anesthetized dogs (group 2) were shaved, and saline solution and histamine were administered ID. Wheal size was measured as for nonanesthetized dogs. Hemoglobin saturation, heart and respiratory rates, and times to sternal recumbency and standing were recorded for anesthetized dogs. Twenty-four hours later, groups were reversed, and testing was repeated on the left side of the thorax.

Results

Mean wheal size was significantly (P < 0.05) less in dogs during propofol anesthesia. Heart and respiratory rates were well maintained but hemoglobin saturation decreased during the first 6 minutes of anesthesia.

Conclusions and Clinical Relevance

Although statistically significant, the difference in mean wheal size may not be clinically important. Propofol anesthesia may be used during ID skin testing in atopic dogs. Further studies to assess effects of propofol on the reactivity of ID injected aeroallergens should be performed before recommending its use. (Am J Vet Res 1998;59:7–9)