bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of monoclonal antibodies and capture immunoassays for feline immunodeficiency virus
Authors: Dreitz Matthew J. , Dow Steven W. , Fiscus Susan A. , Hoover Edward A.
Published: January 2024

We generated monoclonal antibodies (mab) against feline immunodeficiency virus (fiv) and characterized these mab by single competition enzyme immunoassays (eia), immunoblot analysis, and radioimmunoprecipitation. Four mab identified 3 distinct epitopes of the fiv p24/26 gag major core protein. One mab recognized the pl6/17 gag protein; none recognized envelope proteins. We developed an fiv p26 antigen capture eia that proved more sensitive (0.5 ng of p26/ml), less expensive, and less timeconsuming than reverse transcriptase assay. The same mab were used to develop an antibody eia specific for fiv p26. The mab and capture assays reported should prove useful in fiv diagnosis and research.
Subcellular pathologic features of glucocorticoid-induced hepatopathy in dogs
Authors: Rutgers H. Carolien , Batt Roger M. , Vaillant Camille , Riley Jane E.
Published: January 2024

Dogs are particularly susceptible to development of glucocorticoid-induced hepatopathy, but the mechanisms are not well understood. We investigated the pathogenesis of glucocorticoid hepatopathy by examining sequential morphologic and biochemical changes in the liver of dogs during steroid administration.

Six adult Beagles were given prednisolone acetate (4 mg/kg of body weight, once daily for 24 days, im). Serum samples and percutaneous liver biopsy specimens were obtained before the start of the study (treatment day [td] 0) and at td 5, 10, 15, and 25. There were significant (P < 0.05) and progressive increases in serum activities of alkaline phosphatase, γ-glutamyltransferase, and alanine transaminase. Light microscopic changes in liver biopsy specimens included progressive hepatocellular swelling and vacuolation. Electron microscopy revealed glycogen accumulation, peripheral displacement of organelles, and prominent dilatation of bile canaliculi, compared with findings at td 0. Liver biopsy specimens taken at td 25 had significantly (P < 0.05) increased activities of the plasma membrane enzymes, alkaline phosphatase and γ-glutamyltransferase, and 5'-nucleotidase was significantly (P < 0.01) decreased. Subcellular fractionation on reorientating sucrose density gradients revealed high-density peaks of alkaline phosphatase and γ-glutamyltransferase, compatible with a specific increase in the biliary canalicular component of the enzyme activities. Neutral α-glucosidase activity was shifted to the denser fractions, indicative of an increase in the proportion of rough to smooth endoplasmic reticulum and consistent with enhanced synthesis of plasma membrane proteins. There also was evidence for progressive increase in fragility of intracellular organelles, particularly lysosomes.

These findings indicate that glucocorticoid hepatopathy in dogs is associated with progressive alterations not only to the plasma membrane, but also to other subcellular organelles.
Enzyme release by bovine neutrophils
Authors: Watson G. L. , Slocombe R. F. , Robinson N. E. , Sleight S. D.
Published: January 2024

Release of enzymes from cytoplasmic granules has been postulated to have a major role in neutrophil-mediated tissue injury. Secretion or release of primary granules, specific granules, and cytosolic enzymes by bovine neutrophils was examined by quantifying the release of β-glucuronidase, B12-binding protein, and lactate dehydrogenase, respectively, in response to predetermined amounts of phorbol myristate acetate, calcium ionophore, and opsonized zymosan. These responses were compared with the enzyme release induced by exposure to live or dead, unopsonized or opsonized Pasteurella haemolytica. The greatest release of β-glucuronidase, B12-binding protein, and lactate dehydrogenase was observed in neutrophils exposed to live organisms partially because of neutrophil lysis. Bovine neutrophils respond markedly to particulate agonists, live or dead, pathogenic or nonpathogenic, by a selective release of specific granules, an effect enhanced by opsonization. Particulate agonists induce minimal primary granule release other than that induced by cell death. Because bovine neutrophils contain quantitatively high numbers of specific granules, the high rate of secretion/release in response to P haemolytica organisms could have a major role in the tissue responses that characterize the lesions of pneumonic pasteurellosis.
Noninvasive detection of nonsteroidal anti-inflammatory drug-induced gastropathy in dogs
Authors: Meddings Jon B. , Kirk David , Olson Merle E.
Published: January 2024

Nonsteroidal anti-inflammatory drugs (nsaid) are widely used for treatment of people and animals. Their use is limited by frequent side effects commonly involving the gastrointestinal tract, most important of which is development of ulcerating lesions principally in the stomach. Unfortunately, presence of such lesions is often unsuspected because clinical signs may be overlooked until a complication develops. We reported that such damage can be detected by measuring the increase in gastric permeability that is a hallmark of this condition. Sucrose is a novel probe molecule for determination of site-specific gastric permeability. As a disaccharide, it is large enough to be effectively excluded by the intact gastric epithelium, and because it is rapidly digested within the small intestine, absorption of the intact molecule implies damage proximal to this site. Recently, we found that increased sucrose permeability is useful in predicting presence of endoscopically relevant gastric damage in people. We extended these results to the detection of nsaid-induced gastropathy in dogs. Dogs treated with aspirin developed nsaid-induced gastropathy (including gastric ulceration), and the degree of endoscopically detectable damage correlated well with sucrose permeability. Furthermore, healing of these lesions could also be monitored by sequential measurements of sucrose permeability. Sucrose permeability decreased more rapidly than the disappearance of gastric ulcers, suggesting that this technique is more sensitive to generalized mucosal damage than is the presence of discrete, endoscopically visible ulceration. This was confirmed by creating artificial ulcers in the antrum and observing that sucrose permeability was not increased in this setting. We conclude that determination of increased sucrose permeability is a useful, noninvasive means of predicting presence of gastric damage in dogs treated with nsaid.
Pharmacologic interaction of furosemide and phenylbutazone in horses
Authors: Hinchcliff K. W. , McKeever K. H. , Muir W. W. , Sams R. A.
Published: January 2024

The effect of premedication with phenylbutazone on systemic hemodynamic and diuretic effects of furosemide was examined in 6 healthy, conscious, mares. Mares were instrumented for measurement of systemic hemodynamics, including cardiac output and pulmonary arterial, systemic arterial, and intracardiac pressures, and urine flow. Each of 3 treatments was administered in a randomized, blinded study; furosemide (1 mg/kg of body weight, iv) only, phenylbutazone (8.8 mg/kg, po, at 24 hours and 4.4 mg/kg, iv, 30 minutes before furosemide) and furosemide, or 0.9% NaCl. Phenylbutazone administration significantly attenuated, but did not abolish, the diuretic effect of furosemide. Phenylbutazone completely inhibited the immediate effect of furosemide on cardiac output, stroke volume, total peripheral resistance, and right ventricular peak pressure. Premedication with phenylbutazone did not inhibit equally the diuretic and hemodynamic effects of furosemide, indicating that some of furosemide's hemodynamic effects are mediated by an extrarenal activity of furosemide.
Effects of short-term cortisol infusion on growth hormone-releasing hormone stimulation of growth hormone release in sheep
Authors: Thompson K. , Coleman E. S. , Hudmon A. , Kemppainen R. J. , Soyoola E. O. , Sartin J. L.
Published: January 2024

Excess production or long-term administration of glucocorticoids is detrimental to longitudinal growth in people and rats. A portion of this effect is attributed to cortisol inhibition of growth hormone (gh). Glucocorticoid effects are usually studied in subjects under long-term treatment with synthetic, more potent glucocorticoids, and, to the authors' knowledge, have not been examined in domestic animals. We sought to examine the effects of cortisol infusion on gh release in sheep. Cortisol infusion into castrated, male Suffolk sheep (1 to 1.5 years old) caused a significant (P < 0.0001) increase in cortisol concentretion. Basal gh release was not affected over the 4-hour period of infusion. Growth hormone-releasing hormone administration stimulated gh release in both groups (P < 0.001); however, the control group had a greater response to growth hormone-releasing hormone than did the cortisol infused group (P < 0.0001). These results were duplicated in cultured sheep pituitary cells. Cortisol inhibition of gh release may be mediated via enhanced somatostatin release, owing to a direct inhibition of somatotrope function, or a combination of both mechanisms. Because of effects of stress and disease in increasing cortisol concentration, additional study of the mechanisms for cortisol inhibition of gh release in sheep needs to be performed.
Cardiovascular, hormonal, and metabolic responses to severe prolonged hemorrhage in adult sheep
Authors: Wintour E. Marelyn , Moritz Karen M. , Potocnik Simon J.
Published: January 2024

Over a 54-hour period, blood was removed from 8 adult sheep (body weight, 38.1 ± 0.5 kg, mean ± sem ) in 9 episodes, 5 on day 1, 3 on day 2, and 1 on day 3. Cumulative blood loss was 1,630 ± 63, 2,380 ± 71, and 2,693 ± 69 ml on days 1, 2, and 3, respectively. Blood samples (20 ml) were collected from 5 control ewes (33.8 ± 2.8 kg) at equivalent times. Over the first day, mean arterial blood pressure decreased in the hemorrhaged sheep from 101 ± 2 mm of Hg to 76 ± 5 mm of Hg, but returned to control values by the beginning of the second day and, thereafter, was not different from control values. Heart rate was increased after the first hemorrhage episode and remained high throughout the entire protocol. Over the entire period, there were statistically significant decreases in hematocrit, plasma osmolality, sodium, total calcium (P < 0.001 ), potassium, and chloride values (P < 0.05 ). There was no change in plasma phosphate, bicarbonate, creatinine, or magnesium concentrations and an increase in plasma urea nitrogen (P < 0.001 ) concentrations. Plasma arginine vasopressin concentration was increased significantly (P < 0.001 ) over the entire period. Plasma acth concentration was significantly (P < 0.05 ) increased over time, but only some values on day 1 were significantly outside the normal range of the control group data. Because of wide variation between sheep, the group data for aldosterone were not significantly different from control values. Blood volume was restored on day 1 with fluid of osmolality, Na, and Cl composition equivalent to that of plasma. The effects of arginine vasopressin were apparent by day 2, when the major decrease in osmolality and Na and Cl concentrations were observed. The sheep has good capacity to withstand severe, prolonged hemorrhage, most likely because of a large reserve of rbc in the spleen; hematocrit remained at 31% of control values when an estimated 100 % of initial circulating blood volume had been removed.
Effects of stromelysin activity on proteoglycan degradation of canine articular cartilage explants
Authors: Todhunter R. J. , Yeh L.-A. , Sheldon A. , Grisanzio L. , Walker S. L. , Burton-Wurster N. , Lust G.
Published: January 2024

We investigated whether stromelysin activity in the medium of canine articular cartilage explants is associated with proteoglycan degradation in these explants. Cartilage explants were treated with recombinant human interleukin 1α (rh-il-lα), lipopolysaccharide, or canine monocyte-conditioned medium. Proteoglycan synthesis and degradation were measured. Metalloproteinase activity (inhibitable by tissue inhibitor of metalloproteinase 2) in the culture medium was measured by use of fluorimetry with a quenched fluorescent substrate. Western blots of the medium were probed with polyclonal antibodies to human stromelysin, collagenase, and gelatinase.

Neither metalloproteinase activity nor proteoglycan degradation were inducible in canine cartilage explants treated with rh-ll-1α. However, proteoglycan synthesis was significantly (P < 0.05) decreased by concentrations of 10 and 100 ng of rh-il-1α/ml. Metalloproteinase activity in the medium accompanied proteoglycan degradation of cartilage treated with lipopolysaccharide and monocyte-conditioned medium. The metalloproteinase released into the medium was identified as prostromelysin by results of western blotting.
Effects of feeding fumonisin B1 in lactating sows and their suckling pigs
Authors: Becker B. A. , Pace L. , Rottinghaus G. E. , Shelby R. , Misfeldt M. , Ross P. F.
Published: January 2024

The mycotoxin fumonisin B1 (FB1) produced by Fusarium moniliforme in corn causes pulmonary edema in finishing swine. Effects of lower nonlethal amounts and effects in lactating sows with suckling pigs are unknown. An initial study was conducted to determine a nonlethal concentration of FB1 for lactating sows; whether ingested FB1 could be detected in the milk; and whether toxicosis could be detected in the pigs, as determined by necropsy. Another study was conducted to determine toxicosis in the pigs by measuring liver sphinganine-to-sphingosine ratio, and whether ingested FB1 affected T-lymphocyte function in sows and their pigs. Furthermore, sows of this study were maintained in controlled hot (27 to 32 C, 50 to 70% relative humidity) and thermoneutral (21 C, 55% relative humidity) environments to determine whether high temperature exacerbated the effects of FB1. In the first study, 100 μg of FB1/g of corn soybean meal diet was found to be nonlethal when fed for 14 days. Fumonisin B1 was not detected in the milk at 30 ppb and lesions were not found in the necropsied pigs, including 1 from a sow that died of porcine pulmonary edema syndrome after ingesting FB1 at a concentration of 175 ppm. In the second study, differences in liver sphinganine-to-sphingosine ratio of pigs were not found. Expressions of cell surface antigens on blood lymphocytes and lymphocyte proliferation response to various mitogens were not affected by FB1 or high temperature in sows or their pigs. The results indicated that when sows ingested nonlethal concentrations of FB1 for 17 days, there were no detectable amounts of FB1 in the sows' milk and no evidence of toxicosis in their pigs; no significant effect of FB1 on T-lymphocyte function in sows and pigs; and no enhanced toxic effects of FB1 attributable to high temperatures.
Intraocular pressure variation associated with body length in young American alligators (Alligator mississippiensis)
Authors: Whittaker C. J. G. , Heaton-Jones T. G. , Kubilis P. S. , Smith P. J. , Brooks D. E. , Kosarek C. , Mackay E. O. , Gelatt K. N.
Published: January 2024

Using an applanation tonometer, 5 replicate intraocular pressure (iop) measurements were obtained from each eye of 12 young, clinically normal, American alligators. Alligator length ranged from 46 to 117 cm, measured from snout to tail tip. All iop were recorded by a single observer at an ambient temperature of approximately 25 C, and ranged from 5 to 35 mm of Hg. Observer reliability was excellent (intraclass r = 0.93), and iop did not change over the ordered sequence of 5 replicate measurements/eye. Replicate iop measurements were, therefore, averaged in each eye for comparison between eyes of the same alligator. Left and right eye iop were highly correlated within individual alligators (r = 0.92), whereas the mean within-animal difference between left and right eye iop was not statistically significant (95% confidence interval [ci] for the left eye-right eye mean difference, −1.9 to 1.5 mm of Hg). Mean iop determined for 5 confirmed females and 3 confirmed males did not differ significantly between the sexes (95% ci for the male-female difference in means, −2.1 to 3.7 mm of Hg). Mean ± sem iop of 23.7 + 2.1 mm of Hg determined for 4 alligators < 50 cm long was significantly (P = 0.009) greater than mean iop of 11.6 + 0.5 mm of Hg determined for 8 alligators > 50 cm long (95% ci for the difference in means, 8.5 to 15.7 mm of Hg). In young alligators, the relation between body length and iop appears to be nonlinear, possibly with a negative exponent.
Intraocular pressure measurement through two types of plano therapeutic soft contact lenses in dogs
Authors: Miller Paul E. , Murphy Christopher J.
Published: January 2024

Intraocular pressure (iop) was measured by use of Mackay-Marg applanation tonometry in 8 normal, manometrically controlled, enucleated, canine eyes with and without 1 of 2 plano therapeutic soft contact lenses (1 and 2) covering the cornea. Differences were not significant between measurements made without a contact lens and those made through either lens at manometer iop < 30 mm of Hg. At manometer iop ≥ 30 mm of Hg, use of a contact lens tended to result in a statistically greater (P < 0.05) estimate of iop than when a lens was not used. This difference, however, achieved only a maximum of 2.6 mm of Hg at the 80 mm of Hg value, and was not regarded as clinically important. Measurements obtained through lens 1 were not significantly different from those obtained through lens 2. The iop can be accurately estimated in dogs, using the Mackay-Marg tonometer, without removing either type of bandage soft contact lens, thereby avoiding potential disruption of an already compromised cornea.
Flow cytometric analysis of punctate and aggregate reticulocyte responses in phlebotomized cats
Authors: Perkins Paula C. , Grindem Carol B. , Cullins Laura D.
Published: January 2024

Five cats were made anemic by one-time phlebotomy, and their reticulocyte responses were monitored daily for 20 days, using manual enumeration and a standardized feline reticulocyte protocol developed and validated in our laboratory. The reticulocyte responses of 38 clinically normal client-owned cats also were analyzed manually and cytometrically to determine clinical reference ranges.

Increases in the percentage of aggregate reticulocytes over the reference range were detected in 5 of 5 phlebotomized cats, using the cytometric protocol. Only 4 of the 5 cats had an increase by results of manual enumeration. Manual aggregate counts had considerable daily variation and often fluctuated in and out of reference range, whereas cytometric aggregate counts remained consistently increased for distinct periods. Increased numbers of aggregate cells could also be detected for longer periods when evaluated by flow cytometry.

Increased numbers of punctate reticulocytes were detected in 4 of 5 cats, using the cytometric protocol. None of the cats had increased numbers of punctate cells when evaluated by use of the manual technique.

Aggregate reticulocytes in the 38 clinically normal cats ranged from 0.1 to 0.5%, which corresponded to 8,487 to 42,120 cells/μl. Punctate reticulocytes ranged from 2 to 17%, which corresponded to 225,400 to 1,268,584 cells/μl.

Flow cytometry, using a standardized analysis protocol, was a more reliable and sensitive technique for detection and evaluation of feline reticulocytosis than was manual enumeration. The sensitivity of the flow cytometer to small amounts of intracellular nucleoprotein makes this assay especially valuable for detection of punctate reticulocytosis and low degrees of aggregate reticulocytosis in cats.
Measurement of von Willebrand factor-specific mRNA and release and storage of von Willebrand factor from endothelial cells of dogs with type-I von Willebrand's disease
Authors: Meinkoth James H. , Meyers Kenneth M.
Published: January 2024

Objective

To characterize the cellular basis of the plasma von Willebrand factor (vWf) deficiency in Doberman Pinschers with type-I von Willebrand's disease (vWd).

Animals

Five Doberman Pinschers with type-I vWd and 5 clinically normal dogs used as controls.

Procedure

Vascular endothelial cell cultures were used to measure constitutive vWf release, thrombin-stimulated vWf release, baseline intracellular vWf concentration, and vWf mRNA expression.

Results

Cells cultured from vWd-affected dogs were morphologically indistinguishable from cells cultured from control dogs, but had reductions in constitutive vWf release (6.5-fold) and vWf mRNA content (fivefold) that correlated to the reduction in plasma vWf concentration (sixfold) in these dogs. The 9.0-kb, canine vWf message was identified, using a polymerase chain reaction-amplified segment of the canine vWf gene and was similar in size to the human vWf message. The vWd cells also had reductions in baseline intracellular vWf concentration (15.6-fold) and thrombin-stimulated vWf release (14.5- fold). Additionally, it was observed that normal canine endothelial cells from different anatomic locations were heterogeneous with respect to vWf expression.

Conclusions

These findings suggest that the plasma vWf deficit in dogs with type-I vWd results from decreased endothelial cell production of vWf resulting from either decreased transcription of the vWf gene or abnormalities in mRNA processing/stability. This is similar to findings in human beings with type-I vWd.
Comparison of methods for sodium and potassium determination in llama urine
Authors: Christopher Mary M. , Belknap Ellen B. , Meyer D. J. , Lackey Margaret N. , Vap Linda M.
Published: January 2024

Objective

To compare results for sodium and potassium determination on llama urine, using flame emission spectrophotometry (flame photometry), atomic absorption spectrophotometry (AAS), indirect ion-selective electrode potentiometry (ISE), and direct ISE.

Design

Llama urine samples encompassing a wide range of electrolyte concentrations were analyzed for sodium and potassium concentrations, using 4 analytical methods, and results were compared statistically to assess correlation, bias, and potential interferents.

Sample Population

10 healthy male llamas.

Procedure

Urine specimens were obtained from llamas fitted with urine collection apparatus at defined intervals over a 24-hour period. Urine samples were centrifuged, and supernatants were frozen at −70 C until analysis. Analytical procedures were done, using standard laboratory protocols. Means, correlation coefficients, and bias were calculated, and differences were evaluated by ANOVA, with significance set at P < 0.05.

Results

There was strong correlation and good agreement among sodium values obtained by flame photometry, AAS, and indirect ISE. Sodium values obtained by use of direct ISE correlated poorly with other methods; urine is not an acceptable specimen for this method. Only AAS and indirect ISE had good correlation (r > 0.9) for potassium values. Data did not suggest presence of a potassium chelator in llama urine; urine potassium values measured by indirect ISE were significantly higher (by 150 to 200 mmol/L) than those measured by other methods.

Clinical Relevance

Urine electrolyte analysis in llamas resulted in less agreement between methods than is generally found for serum. Data collection for patient monitoring or research analysis should be restricted to a single method to avoid differences in results attributable to analytical variance. (Am J Vet Res 1996;57:25-30
Infection and cross-protection studies of winter dysentery and calf diarrhea bovine Coronavirus strains in colostrum-deprived and gnotobiotic calves
Authors: El-Kanawati Zakaria R. , Tsunemitsu Hiroshi , Smith David R. , Saif Linda J.
Published: January 2024

Objective

To investigate in vitro antigenic relations, in vivo cross-protection, and isotype antibody responses to a winter dysentery (WD) and calf diarrhea strain of bovine coronavirus (BCV).

Design and Animals

Gnotobiotic and colostrum-deprived calves were inoculated oronasally with a WD (DBA) or a calf diarrhea (DB2) BCV, and were challenge exposed with the heterologous BCV.

Procedure

Nasal swab and feces specimens and blood samples were collected. Fecal and nasal specimens were assayed for BCV shedding by antigen-capture ELISA or immune electron microscopy. Bovine coronavirus antigens were detected in nasal epithelial cells by immunofluorescence. Antibody titers to BCV in serum were assayed by virus neutralization (VN), and BCV antibody isotype titers in feces and sera were quantitated by ELISA.

Results

All calves developed diarrhea and shed BCV nasally and in feces, then recovered and were protected from BCV-associated diarrhea after challenge exposure with the heterologous BCV. After challenge exposure with either strain, fecal shedding of DBA was detected in 1 of 4 calves and nasal shedding of DB2 was detected in 2 of 4 calves. Immunoglobulin M was the principal coproantibody to BCV early, followed predominantly by IgA. Immunoglobulin G1 coproantibody titers to BCV were low, but increased after challenge exposure. Immunoglobulin G1 antibodies were predominant in serum. After challenge exposure, all serum antibody isotype titers increased except IgG2. The VN antibody responses paralleled serum IgG1, antibody responses.

Conclusions and Clinical Relevance

Immunoglobulin A coproantibodies at challenge exposure were associated with protection against diarrhea. Nasal shedding of BCV after challenge exposure confirmed field data documenting reinfection of the respiratory tract of cattle, suggesting that, in closed herds, respiratory tract infections constitute a source of BCV transmission to cows (WD) or young calves. (Am J Vet Res 1996;57:48-53)
Comparison of two techniques of narcotic-induced anesthesia for use during recording of magnetic motor evoked potentials in dogs
Authors: Van Ham Luc M. L. , Nijs Jozef , Vanderstraeten Guy G. W. , Mattheeuws Daniel R. G.
Published: January 2024

Objective

To compare 2 types of narcotic-induced anesthesia for recording of transcranial magnetic motor evoked potentials (TMMEP) in dogs.

Design

The effect of different doses of sufentanil and midazolam and of sufentanil and nitrous oxide on onset latencies and peak-to-peak amplitudes of TMMEP was evaluated and compared.

Animals

18 neurologically normal dogs.

Procedure

Premedication with droperidol and fentanyl. Induction and maintenance of anesthesia either with sufentanil and midazolam or with sufentanil and nitrous oxide. Recording of TMMEP from the extensor carpi radialis muscle of the forelimb and from the cranial tibial muscle of the hind limb.

Results

Both types of narcotic anesthesia induced dose-dependent suppression of TMMEP; compared with baseline recordings, latencies increased, amplitudes decreased, and reproducibility became poorer with increasing dose of the anesthetics. Using surgical-depth doses of the anesthetics, TMMEP could still be recorded in all dogs with sufentanil and nitrous oxide, but not with sufentanil and midazolam anesthesia.

Conclusions

Sufentanil and nitrous oxide anesthesia was superior to sufentanil and midazolam anesthesia for TMMEP recording.

Clinical Relevance

In small animal medicine, and in dogs in particular, spinal cord diseases are among the most frequently encountered neurologic disorders. The development of techniques for recording TMMEP in anesthetized dogs allows noninvasive evaluation of transmission along descending motor pathways of the spinal cord.
Antigenic and restriction enzyme analysis of Campylobacter spp associated with abortion in sheep
Authors: Delong W. J. , Jaworski M. D. , Ward A. C. S.
Published: January 2024

Objective

To determine the scope of strain variations among Campylobacter spp associated with abortion in sheep.

Design

To examine Campylobacter spp isolated from cases of abortion for biochemical, antigenic, and genetic differences.

Sample Population

15 isolates of Campylobacter spp isolated from cases of abortion during a single lambing season.

Procedure

Isolates were examined, using biochemical tests, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of outer membrane proteins (OMP), and DNA restriction enzyme analysis (REA).

Results

Eight strain variants were detected among the 15 isolates. 14 of the isolates were C jejuni, 13 of which were biotype I and 1 biotype II, and the remaining isolate was identified as C fetus subsp fetus. Five sodium dodecyl sulfate-polyacrylamide gel electrophoresis OMP patterns had distinctive profiles for C fetus subsp fetus and C jejuni biogroup-II isolates and 3 variants within the C jejuni bio-group-I isolates. Examination of REA patterns of DNA from the 15 isolates digested with Cfo I indicated clear differences correlating with species and biogroups and 4 REA variants among biotype-l isolates.

Conclusions

Marked antigenic and genetic heterogeneity of Campylobacter isolates were associated with ovine abortion within a defined geographic area.

Clinical Relevance

Representatives of differing OMP and REA profile groups should be considered for incorporation in vaccines to optimize protection in this region and possibly other geographic areas.
Lipid peroxidation in free skin grafts in rats
Authors: McCarthy Paul E. , Hosgood Giselle , Church Daniel F.
Published: January 2024

Objective

To evaluate accumulation of products of lipid peroxidation in free skin grafts in rats over 10 days after grafting.

Design

Prospective analysis.

Animals

30 adult Sprague-Dawley rats.

Procedure

Free skin grafts were applied to 1 hemithorax of 30 rats (2 groups, n = 15/ group), the other hemithorax acting as a nongrafted control. Biopsy specimens were taken from the nongrafted side of all rats immediately before and from the nongrafted and grafted sides immediately after the procedure. Biopsy specimens of both sides of the thorax were performed on days 1, 3, and 7 after grafting in group-1 rats, and on days 2, 4, and 10 after grafting in group-2 rats. Thiobarbituric acid (TBA) analysis for malondialdehyde and other aldehydic products (TBA-reactive substances) was used to determine lipid peroxidation. Concentration of TBA-reactive substances was determined by absorbance spectrophotometry at a wavelength of 532 nm.

Results

Accumulation of products of lipid peroxidation, reflected by increase in absorbance, continued to increase over the 10 days of this study. Difference in absorption between the nongraft and graft biopsy specimens was significant (P = 0.0011). Absorbance on days 3 and 4 was significantly higher than control and day-0 values (P ≤ 0.05). Absorbance on days 7 and 10 was significantly higher than control, day-0, and day-1 values (P ≤ 0.05). Rate of increase in absorption was maximal at day 4 and rapidly decreased thereafter.

Conclusion

Accumulation of lipid peroxidation products in skin grafts may be best explained by oxygen-derived free radical-induced injury attributable to postischemic reperfusion. Maximal rate of accumulation corresponded to the known time of graft recirculation and revascularization.

Clinical Relevance

Predictability of free radical damage may allow timely pharmacologic intervention to reduce radical formation and ameliorate effects of peroxidation. Such intervention may help increase free graft survival or mitigate the effects of vascular compromise to axial pattern flaps.
Efficacy dose determination study of tilmicosin phosphate in feed for control of pneumonia caused by Actinobacillus pleuropneumoniae in swine
Authors: Moore Gregory M. , Mowrey Daniel H. , Tonkinson Lealon V. , Lechtenberg Kelly F. , Schneider John H.
Published: January 2024

Objective

To determine the effective dosage of tilmicosin phosphate when fed to pigs for the control of pneumonia attributable to Actinobacillus pleuropneumoniae.

Design

Randomized complete block design, with initial weight as the blocking factor.

Animals

Seeder pigs were used to infect clinically normal male and female pigs weighing between 13.6 and 36.3 kg at each of 4 trials.

Procedure

Five doses of tilmicosin phosphate (0, 100, 200, 300, and 400 µg/g) were fed to pigs for 21 days. Pigs received experimental feeds 7 days before the seeder pigs were placed into pens. Feeding continued for an additional 14 days, with seeder pigs removed 3 to 8 days after placement. All pigs were euthanatized and necropsied, with lung bacterial flora and percentages of pneumonic involvement determined.

Results

Improvement in clinical impression score, daily rectal temperature, and weight gain were seen for all doses of tilmicosin, compared with controls. For the same variables, tilmicosin administered at 200 to 400 µg/g resulted in improvements over the 100 µg/g dose.

Conclusions

Data indicate that tilmicosin phosphate fed to pigs at 200 to 400 µg/g is effective in controlling and preventing A pleuropneumoniae-induced pneumonia, when administered in feed for 21 days.
Canine glyceraldehyde-3-phosphate dehydrogenase complementary DNA: Polymerase chain reaction amplification, cloning, partial sequence analysis, and use as loading control in ribonuclease protection assays
Authors: Gröne Andrea , Weckmann Michelle T. , Capen Charles C. , Rosol Thomas J.
Published: January 2024

Objective

To use canine glyceraldehyde-3-phosphate dehydrogenase complementary DNA (GAPDH cDNA) as a template in ribonuclease (RNase) protection assays to measure canine GAPDH mRNA expression.

Design and Procedure

Primers designed from the human GAPDH gene were used to amplify a 191 -base pair canine GAPDH cDNA by reverse-transcription polymerase chain reaction. The cDNA was sequenced, and used as a template for RNase protection assay.

Sample Population

Total RNA was isolated from a canine squamous carcinoma cell line.

Results

Canine GAPDH cDNA had a high degree of homology to human, rat, and mouse GAPDH. In vitro transcription of canine GAPDH cDNA was used to produce complementary RNA that detected canine GAPDH mRNA by RNase protection assay.

Conclusion

Canine GAPDH cDNA is a useful loading control to be used in RNase protection assays measuring mRNA expression in canine cells or tissues.
Performance traits, hoof mineral composition, and hoof characteristics of bulls in a 112-day postweaning feedlot performance test
Authors: Sugg J. L. , Brown A. H. , Perkins J. L. , Phillips J. M. , Kellogg D. W. , Johnson Z. B.
Published: January 2024

Objective

To evaluate relations between hoof and performance data from bulls fed in a 112-day standardized postweaning feedlot performance test.

Animals and Design

Breeds included were Angus (n = 20), Brangus (n = 19), Hereford (n = 31), and Simmental (n = 53). Hoof measurements, scores, and a 0.5g hoof tissue sample were obtained from the right forefoot of bulls on days 1 and 112 of 4 tests conducted in 3 locations in Arkansas. Data were analyzed, using least squares ANOVA. The model used included an overall mean, breed, farm of origin within breed, initial age, and initial weight within breed and residual. Residual and canonical correlations of the traits studied were calculated.

Results

Residual correlations were found between some hoof minerals. Canonical correlations between performance traits and hoof minerals, between hoof characteristics and hoof minerals, and between hoof characteristics and performance traits were 0.62 and 0.45 (P < 0.05), 0.54 and 0.40 (P < 0.05), and 0.56 (P < 0.01) and 0.26 (P > 0.05), respectively.

Conclusions

These data suggest that a relation exists between performance traits and hoof mineral composition and hoof characteristics and mineral composition. The visual scoring system for these data did not genetically separate bulls on the basis of claw quality.

Clinical Implications

By selecting bulls with high claw quality, cattle producers are decreasing the chances of premature culling because of hoof laminitis. Therefore, by obtaining hoof measurements and mineral composition in a feedlot performance test, producers should have the tools to select bulls for increased lifetime performance.(Am J Vet Res 1996;57:291-295)
Attempt to pharmacologically modulate procoagulant activity of lipopolysaccharide-stimulated adherent bovine alveolar macrophages
Authors: Olchowy Timothy W. J. , Dean David F. , Bochsler Philip N.
Published: January 2024

Objective

To investigate the effects of anti-inflammatory drugs on lipopolysaccharide-induced procoagulant activity of bovine alveolar macrophages.

Design

Procoagulant activity was induced in bovine alveolar macrophages from 4 healthy Holstein calves aged 6 to 16 weeks by incubation with lipopolysaccharide. 3 anti-inflammatory drugs were used at 4 concentrations and 3 times to pretreat the alveolar macrophages. Results were analyzed to determine whether drug, concentration, or exposure period had a significant (P> 0.05) effect.

Procedure

Bovine alveolar macrophages, harvested by volume-controlled bronchoalveolar lavage, were pretreated for 30, 60, or 120 minutes with an anti-inflammatory compound (dexamethasone, flunixin meglumin, or phenylbutazone) at several concentrations (0, 1, 10, and 100 μM). Bovine alveolar macrophages were exposed to lipopolysaccharide (Escherichia coli O55:B5) in the presence and absence of fetal bovine serum for 4 hours. Procoagulant activity was measured, using a chromogenic assay.

Results

None of the drugs was associated with a modification of procoagulant activity expression.

Conclusion

Use of these 3 anti-inflammatory drugs is unlikely to modify the extent of the fibrinous reaction commonly observed in cases of acute bovine respiratory tract disease complex.

Clinical Relevance

The alveolar macrophage has a key role in fibrin production. Assuming in vivo events mimic the in vitro model, is appears unlikely that administration of anti-inflammatory drugs will reduce the procoagulant activity of the bovine alveolar macrophages and the directly associated pulmonary fibrosis. (Am J Vet Res 1996; 57:659–663)
Serum α-tocopherol, vitamin A, and blood selenium concentrations, and glutathione peroxidase activity in llamas fed alfalfa hay
Authors: Dart Andrew J. , Kinde Hialu , Hodgson David R. , Peauroi John R. , Selby Arthur W. , Maas John , Fowler Murray E.
Published: January 2024

Objectives

To measure blood selenium concentration and glutathione peroxidase (GSH-Px) activity and serum concentrations of vitamin A and α-tocopherol, and to determine the correlation between blood selenium concentration and GSH-Px activity of llamas fed alfalfa hay.

Design

Mean (± SD) serum vitamin A and α-tocopherol concentrations, blood selenium concentrations, and GSH-Px activity were calculated from 9 sequential blood samples collected from llamas fed a diet of alfalfa hay.

Animals

15 clinically normal llamas (8 males, 7 females) between 10 and 14 months of age.

Procedure

Llamas were fed alfalfa hay for 40 days prior to sample collection and then for the duration of the trial. Vitamin E, selenium, and concentrations of vitamin A precursors were measured in the hay. Blood samples were collected on days 0, 6, 7, 9, 13, 20, 42, 64, and 98. Blood selenium concentrations were measured, using an inductively coupled spectrometric method. Blood GSH-Px activity was measured with a spectrophotometer, using a modification of a previously described assay. Isocratic high-performance liquid chromatography with florescent detection was used to determine serum α-tocopherol and vitamin A concentrations.

Results

The alfalfa hay contained 0.2 mg/kg of selenium, 5 mg/kg of vitamin E, and 0.9 mg/kg of vitamin A precursors. The mean (± SD) blood selenium concentration and GSH-Px activity were 0.179 ± 0.032 pg/ml and 25.76 ± 6.53 mU NADPH oxidized/min/mg of Hb, respectively, with a correlation coefficient of 0.97. The mean (± SD) concentrations for serum α-tocopherol and vitamin A were 128.1 ± 41.7 and 74.8 ± 5.5 μg/dl, respectively.

Conclusions

Blood selenium concentrations in llamas are highly correlated to GSH-Px activity. Blood selenium concentrations in llamas appear to be similar to other domestic ruminants and diets containing 0.2 mg/kg of selenium appear to provide an adequate dietary source. The concentrations of vitamin A precursors and vitamin E in the hay were below currently recommended dietary levels for llamas, and alfalfa hay appears to provide an unreliable source of vitamins A and E in this species. Further studies are required to determine optimal dietary concentrations and to substantiate a reference range for these vitamins in llamas. (Am J Vet Res 1996; 57:689–692)
Determination of the lifespan of erythrocytes from Greyhounds, using an in vitro biotinylation technique
Authors: Novinger M. Stewart , Sullivan Patrick S. , McDonald T. P.
Published: January 2024

Objective

To determine the RBC lifespan of Greyhounds, using an in vitro labeling technique.

Design

RBC from dogs were labeled with NHS-biotin and their disappearance measured over time to determine RBC lifespan.

Sample Population

5 Greyhounds that had been vaccinated against distemper, adenovirus 1 and 2 infections, parainfluenza, leptospirosis, parvovirus, and coronavirus infections, Bordetella bronchiseptica infection, and rabies the previous year; 3 sexually intact 14-month-old Beagles served as controls.

Procedure

After venipuncture for CBC, catheters were inserted in the cephalic vein of each dog. Butorphanol was then administered to achieve mild sedation and analgesia, and glycopyrrolate was administered to ensure maintenance of adequate heart rate during phlebotomy. Dogs were positioned in lateral recumbency; blood was removed via jugular venipuncture, using a standard laboratory donor blood bag containing citrate-phosphate-dextrose solution. Blood was transferred aseptically into sterile polystyrene containers and NHS-biotin was added. After incubation, the labeled RBC were reinfused into the dogs and the blood was allowed to recirculate for 1 hour before the first postinfusion sample was taken. At frequent intervals, blood to be analyzed was taken by jugular venipuncture, and the percentage of labeled cells was determined by flow cytometry.

Results

The mean RBC lifespan of non-Greyhounds was significantly longer than that of Greyhounds (104.3 ± 2.2 days vs 53.6 ± 6.5 days; P = 0.001). A negative linear correlation was also found between age of the Greyhounds and their RBC lifespan (P = 0.01, R2= 0.91).

Conclusions

The shorter RBC lifespan of the Greyhounds may explain the finding of macrocytosis reported in earlier work. The reason for the shorter RBC lifespan in Greyhounds may be caused by differences in Greyhound RBC membrane structure or accelerated RBC removal from the circulation. (Am J Vet Res 1996; 57:739–742)
Calculation of maximal removal rate of indocyanine green to measure hepatic functional mass in dogs by use of the nine-hour method
Authors: Furuhama Kazuhisa , Goi Shoko , Kawarabayashi Keiko , Maru Chikako , Inage Fujio
Published: January 2024

Objective

To establish a versatile and reliable procedure for the determination of indocyanine green maximal removal rate (ICG Rmax) to measure hepatic functional mass in dogs within 9 hours (9-hour method).

Design

Relation between 9-hour and standard 3-day methods was examined.

Animals

101 healthy dogs.

Procedure

On investigation of the optimal technical conditions allowing completion of all procedures in a day, the appropriate IV administered doses of ICG were 0.125, 0.5, and 2.0 mg/kg of body weight, and the best blood sample collection times for obtaining plasma half-life at these 3 doses were before and 3, 6, and 9 minutes after ICG administration.

Results

Comparison of the 9-hour with 3-day method yielded a correlation coefficient (r) of 0.84, indicating close (P < 0.01) correlation. In the 9-hour method, mean ± SD of ICG Rmax in healthy dogs was 0.24 ± 0.09 mg/kg/min in male (n = 62) and was 0.23 ± 0.06 mg/kg/min in female (n = 21) Beagles, and was 0.21 ± 0.10 mg/kg/min in male (n = 11) and 0.20 ± 0.07 mg/kg/min in female (n = 7) mixed-breed dogs. In Beagles treated orally with carbon tetrachloride (0.1 ml/kg in gelatine capsules) thrice weekly during a 10-week period, plasma alanine transaminase activity plateaued at a high value (> 2,000 IU/L) on day 5, and remained at this value until the end of the study. The ICG Rmax changed accordingly: day 5, 0.17; day 10, 0.11; day 40, 0.05; and day 60, 0.06 mg/kg/min.

Conclusion

The 9-hour method for determination of ICG Rmax correlates favorably with the 3-day method.

Clinical Relevance

This procedure may be practically applied in veterinary clinics in terms of prediction of hepatic functional mass, and for diagnosis of hepatotoxicosis induced by certain compounds. (Am J Vet Res 1996;57:803–806)
Ketoprofen concentrations in plasma and milk after intravenous administration in dairy cattle
Authors: DeGraves F. J. , Riddell M. G. , Schumacher J.
Published: January 2024

Objective

To determine plasma and milk concentration-time profiles and pharmacokinetic variables after IV administration of ketoprofen to lactating dairy cows.

Design

Cows received a single IV bolus of ketoprofen (3.31 mg/kg of body weight). Blood and milk were collected at 0, 5, 10, 15, 25, 40, 60, 90, 120, 180, 240, 360, and 480 minutes. Ketoprofen concentrations in plasma and milk were determined.

Animals

6 clinically normal lactating Holstein cows.

Procedure

Plasma and milk samples were processed by solvent extraction, and ketoprofen concentrations were determined, using high-performance liquid chromatography with octadecyl silane reverse-phase guard and analytic columns. A computer polyexponential curve-stripping program was used to fit ketoprofen concentration-time data and to calculate pharmacokinetic variables.

Results

The lower limit of detection for ketoprofen in plasma was 18 ng/ml; the lower limit of quantification was 60 ng/ml. The lower limit of detection for ketoprofen in milk was 27 ng/ml; the lower limit of quantification was 90 ng/ml. Plasma ketoprofen concentration-time curves best fit an open two-compartment pharmacokinetic model. Harmonic mean apparent volume of distribution at steady state was 0.11 (range, 0.095 to 0.13) L/kg, elimination half-life was 0.49 (range, 0.40 to 0.67) hour, and total clearance was 0.17 (range, 0.14 to 0.19) L/kg/h. Ketoprofen was detected in some milk samples, 10 to 120 minutes after administration, but all concentrations were below the limit of quantification. Adverse effects were not observed in cows given ketoprofen.

Conclusions

The elimination half-life for ketoprofen is short, and low concentrations of ketoprofen can be detected in normal milk, after IV treatment of cattle with ketoprofen. Milk and meat from cattle treated IV with ketoprofen should not be an important drug residue risk if appropriate withholding periods are used. (Am J Vet Res 1996;57:1031–1033)