bluuebunny/crossref_metadata_2025 huggingface dataset:
Isoelectric focusing of soluble proteins from Fasciola hepatica L, 1758 and Fascioloides magna B, 1875
Authors: Lee C. G. , Zimmerman G. L. , Mulrooney D. M.
Published: January 2024

Isoelectric focusing was performed on the soluble proteins of whole-body and excretory-secretory products (esp) of Fasciola hepatica and Fascioloides magna. Adult F hepatica flukes were recovered from experimentally infected sheep and esp obtained from the flukes; portions of liver were cut and frozen at - 70 C. Fascioloides magna adults were collected from naturally infected white-tailed deer and esp obtained; portions of liver were collected from noninfected white-tailed deer.

Adult flukes and their host tissues were homogenized and centrifuged; protein concentrations with their esp were determined and adjusted to < 2.50 mg/ml. Seven esp samples from F hepatica and 1 from Fascioloides magna were subjected to isoelectric focusing with the 2 species of fluke and their respective host liver homogenates. After separation, gels were stained with silver and scanned on a laser densitometer.

Protein banding patterns of the 2 species of flukes were dissimilar. In the pH range of 3.5 to 9.6, the body protein had approximately 30 peaks and esp about 23 peaks in both species. Overall banding patterns of the body protein and esp of both species were distinct from those of respective host tissues. Of the peaks reported as dominant, 3 of the body protein and 2 of esp were shared between the 2 species. Fascioloides magna had more dominant peaks than F hepatica. This technique of soluble protein isoelectric focusing is simple and reproducible, and the 2 fluke species can easily be differentiated by this technique, as well as by morphologic characteristics.
Prevalence of Haemophilus parasuis serovars among isolates from swine
Authors: Rapp-Gabrielson Vicki J. , Gabrielson David A.
Published: January 2024

Two hundred sixty Haemophilus spp isolates that had been obtained from the respiratory tract and other sites of swine were acquired from diagnostic laboratories, primarily in the United States and Canada. The majority of isolates (243/260) were biochemically characterized as H parasuis; however, a few isolates of taxa distinct from H parasuis (taxa "minor group," D, E, and F) were identified. Fourteen H parasuis serovars were identified, and of those previously described, the most prevalent were 5 (24.3% of isolates), 4 (16.1%), 2 (8.2%), and 7 (3.7%). Three new serovars that were also prevalent included ND4 (11.1%), ND3 (8.6%), and ND5 (6.6%). Serovars 1, 3, 6, C, D, and new serovars ND1 and ND2 were infrequently identified, and 15.2% of isolates were nontypeable. It was not uncommon to isolate multiple serovars from swine of the same herd or related herds. Distribution of serovars among isolates from the United States and Canada was generally similar; however, a higher prevalence of serovar 5 and a lower prevalence of serovars 2, ND3, and ND5 were evident in isolates from Canada. Comparison of isolates obtained from the respiratory tract of swine without polyserositis with those obtained from swine with polyserositis revealed an increased frequency of serovars 4 and 5, and a decreased frequency of serovar 2, among isolates from swine with polyserositis. However, all prevalent serovars were isolated from swine with polyserositis, and data were not indicative of an association between serovar, site of isolation, or pathogenic potential.
Pharmacokinetics of phenobarbital in horses after single and repeated oral administration of the drug
Authors: Knox D. A. , Ravis W. R. , Pedersoli W. M. , Spano J. S. , Nostrandt A. C. , Krista L. M. , Schumacher J.
Published: January 2024

Six healthy mature horses were orally administered a single dose of phenobarbital (26 mg/kg of body weight), then multiple doses (13 mg/kg) orally for 42 consecutive days. Seventeen venous blood samples were collected from each horse after the single dose study and again after the last dose on day 42. Plasma phenobarbital concentration was determined by use of a fluorescence assay validated for horses. Additional blood samples (n = 11) were collected on days 8 and 25 to determine peak and trough concentrations, as well as total body clearance. Phenobarbital disposition followed a one-compartment model. Mean kinetic variables after single and repeated orally administered doses (42 days) were: elimination half-life = 24.2 ± 4.7 and 11.2 ± 2.3 hours, volume of distribution = 0.960 ± 0.060 and 0.914 ± 0.119 L/kg, and clearance = 28.2 ± 5.1 and 57.3 ± 9.6 ml/h/kg, respectively. Results indicated that significant (P < 0.05) difference in half-life and oral clearance existed between single and repeated dosing. The significant decrease in half-life after repeated dosing with phenobarbital may be indicative of enzyme induction. Significant difference was not observed between baseline serum enzyme concentration and concentration measured on day 42, except for γ-glutamyltransferase activity, which was significantly increased on day 42 in 3 of the 6 horses. On the basis of increases in oral clearance observed over 42 days, dose adjustments may be required. By days 25 to 42, pharmacokinetic values indicated that dosages of phenobarbital between 25 and 27 mg/kg administered orally every 24 hours may be needed to maintain steady state plasma concentration of phenobarbital at 20 μg/ml of plasma in mature horses.
Influence of furosemide on hemodynamic responses during exercise in horses
Authors: Olsen S. C. , Coyne C. P. , Lowe B. S. , Pelletier N. , Raub E. M. , Erickson H. H.
Published: January 2024

Four hours prior to exercise on a high-speed treadmill, 4 dosages of furosemide (0.25, 0.50, 1.0, and 2.0 mg/kg of body weight) and a control treatment (10 ml of 0.9% NaCl) were administered iv to 6 horses. Carotid arterial pressure (cap), pulmonary arterial pressure (pap), and heart rate were not different in resting horses before and 4 hours after furosemide administration. Furosemide at dosage of 2 mg/kg reduced resting right atrial pressure (rap) 4 hours after furosemide injection. During exercise, increases in treadmill speed were associated with increases in rap, cap, pap, and heart rate. Furosemide (0.25 to 2 mg/kg), administered 4 hours before exercise, reduced rap and pap during exercise in dose-dependent manner, but did not influence heart rate. Mean cap was reduced by the 2-mg/kg furosemide dosage during exercise at 9 and 11 m/s, but not at 13 m/s. During recovery, only rap was decreased by furosemide administration. Plasma lactate concentration was not significantly influenced by furosemide administration. Furosemide did not influence pcv or hemoglobin concentration at rest prior to exercise, but did increase both variables in dose-dependent manner during exercise and recovery. However, the magnitude of the changes in pcv and hemoglobin concentration were small in comparison with changes in rap and pap, and indicate that furosemide has other properties in addition to its diuretic activities. Furosemide may mediate some of its cardiopulmonary effects by vasodilatory activities that directly lower pulmonary arterial pressure, but also increase venous capacitance, thereby reducing venous return to the atria and cardiac filling.
Efficacy of ivermectin delivered from a sustained-release bolus against inhibited early fourth-stage larvae of Ostertagia ostertagi and other nematodes in cattle
Authors: Williams J. C. , Plue R. E.
Published: January 2024

The anthelmintic efficacy of ivermectin (ivm) delivered from a sustained-release (sr) bolus was evaluated against natural infections with gastrointestinal tract nematodes in 12 crossbred beef heifers in spring. The 12 calves were randomly allotted to 2 groups of 6 calves each. Group-1 calves were treated with an sr bolus designed to deliver 8 mg of ivermectin/d. Group-2 calves were nontreated controls. Cattle groups were kept in separate concrete-floored pens (grass hay nutrition) and slaughter was performed at 35 days after treatment. Fecal egg counts for group-1 calves remained zero after treatment, except for detection of < 1 egg/g of feces in 1 calf at the time of slaughter; counts in nontreated calves increased. Mean and range of Ostertagia ostertagi inhibited larvae in nontreated calves were 27,093 and 10,622 to 56,368, respectively. Efficacy of the ivm sr bolus was 100% against O ostertagi developing fourth-stage larvae (L4) and inhibited early L4, Haemonchus placei adults, Cooperia punctata and C spatulata adult males, Cooperia spp adult females, Cooperia spp L4, Trichostrongylus colubriformis adults, Bunostomum phlebotomum adults, and Oesophagostomum radiatum adults. Efficacy for O ostertagi and T axei adults was 99.9%. Numbers of nontreated calves infected with C pectinata adult males and Oes radiatum L4 were too low to evaluate efficacy. Calves treated with the ivm bolus gained 10.2 kg, whereas nontreated calves lost 1.8 kg. Abomasal lesions were clearly greater in nontreated calves on the basis of index comparisons of abomasal weight and total live weight and gross pathologic features.
Inhibition of equine mononuclear cell proliferation and leukotriene B4 synthesis by a specific 5-lipoxygenase inhibitor, A-63162
Authors: Olsen S. C. , Atluru D. , Atluru S. , McVey D. S. , Erickson H. H.
Published: January 2024

The lipoxygenase metabolites of arachidonic acid have an important role in lymphocyte activation. We used a specific 5-lipoxygenase inhibitor, A-63162, to examine the role of 5-lipoxygenase (5-lo) in equine blood mononuclear cell (bmc) proliferation and leukotriene B4 (ltb4) synthesis after stimulation with mitogen (phytohemagglutinin, pha) or calcium ionophore (A23187). The A-63162 inhibited pha-induced equine bmc proliferation and, at the same concentration, also inhibited A23187-induced ltb4 synthesis. The presence of exogenous interleukin 2 (il-2) or the cyclooxygenase inhibitor indomethacin, failed to reverse the immunosuppression caused by A-63162. Further, we found that A-63162, at the concentration that inhibited bmc proliferation and ltb4 synthesis, had no effect on bmc viability. The addition of the specific protein kinase C inhibitor, H-7, did not inhibit A23187-induced ltb4 synthesis. Results indicate that 5-lipoxygenase metabolites may have an important role in equine lymphocyte activation and that protein kinase C has no role in regulating ltb4 production after A23187 stimulation.
Cardiopulmonary responses to experimentally induced gastric dilatation in isoflurane-anesthetized dogs
Authors: Hodgson D. S. , Dunlop C. I. , Chapman P. L. , Grandy J. L.
Published: January 2024

Gastric dilatation was experimentally induced in 6 anesthetized dogs maintained with constant-dose isoflurane in oxygen. An intragastric balloon was used to distend the stomach with a constant 30 mm of Hg pressure for 3.5 hours. The was maintained between 35 and 45 mm of Hg, using intermittent positive-pressure ventilation. Cardiopulmonary measurements prior to stomach distension (baseline) were compared with measurements taken during 0.1, 0.5, 1.0, 1.5, 2.5, and 3.5 hours of stomach distension by analyzing the change from baseline in a randomized-block analysis with each dog as a block. After distending the stomach, cardiac index increased (P < 0.01) from 1.5 to 3.5 hours. Stroke volume did not change, thus the increase in the cardiac index was attributable to an increase in heart rate. During inflation, increases were observed in systemic arterial, pulmonary arterial, and right atrial pressure. Respiratory frequency was unchanged; however, to maintain constant, it was necessary to progressively increase peak airway pressure. Although tended to decrease during gastric dilation, the dogs were never hypoxemic. These results indicate that when our methods are used to maintain a constant anesthetic dose of isoflurane in oxygen, an observed increase in cardiovascular performance is expected. This differs from other studies in anesthetized dogs that have shown reduction in cardiovascular performance following gastric dilatation.
Plasma renin activity and aldosterone and vasopressin concentrations during incremental treadmill exercise in horses
Authors: McKeever Kenneth H. , Hinchcliff Kenneth W. , Schmall L. Michael , Reed Stephen M. , Lamb David R. , Muir William W.
Published: January 2024

Six untrained mares were subjected to incremental treadmill exercise to examine exercise-induced changes in plasma renin activity (pra) and plasma aldosterone (aldo) and plasma arginine vasopressin (avp) concentrations. Plasma renin activity, aldo and avp concentrations, and heart rate (hr) were measured at each step of an incremental maximal exercise test. Mares ran up a 6° slope on a treadmill set at an initial speed of 4 m/s. Speed was increased 1 m/s each minute until hr reached a plateau. Plasma obtained was stored at − 80 C and later was thawed, extracted, and assayed for pra and aldo and avp values by use of radioimmunoassay. Exercise caused significant increase in hr from 40 ± 2 beats/min (mean ± sem) at rest to 206 ± 4 beats/min (hrmax) at speed of 9 m/s. Plasma renin activity increased from 1.9 ± 1.0 ng/ml/h at rest to a peak of 5.2 ± 1.0 ng/ml/h at 9 m/s, paralleling changes in hr. Up to treadmill speed of 9 m/s, strong linear correlations were obtained between exercise intensity (and duration) and hr (r = 0.87, P < 0.05) and pra (r = 0.93, P < 0.05). Heart rate and pra reached a plateau and did not increase when speed was increased from 9 to 10 m/s. Plasma aldo concentration increased from 48 ± 16 pg/ml at rest to 191 ± 72 pg/ml at speed of 10 m/s. Linear relation was found between exercise intensity (and duration) and aldo concentration (r = 0.97, P < 0.05). Plasma avp concentration increased from 4.0 ± 3.0 pg/ml at rest to 95 ± 5.0 pg/ml at speed of 10 m/s. The relation between avp concentration and exercise intensity (and duration) appeared to be curvilinear, and was described by an exponential function (r = 0.92, P < 0.05). These data indicate that pra and aldo and avp concentrations increase in horses during progressive treadmill exercise.
Effect of bilateral stimulation on spinal evoked potentials in dogs
Authors: Poncelet L. , Delauche A. , Vinals C. , Balligand M.
Published: January 2024

We compared the effects of bilateral vs unilateral tibial nerve stimulation of percutaneously recorded spinal evoked potentials (sep) in the lumbar and caudal thoracic area in dogs. The overall amplitude of the sep is increased by this means. Use of this method could improve legibility of the recordings. Amplitudes of root and interneuronal components of the sep are doubled as are cranially transmitted depolarizations. However, the amplitude of the sep component arising from the primary afferents’ depolarization was less than doubled. Latencies of the components were unaffected by bilateral stimulation. Careful observation of the latencies disclosed a 0.9-ms delay in transmission of the fastest component in the midlumbar area. This delay was consistant with results of previous cordotomy experiments, and could influence precision of conduction velocity measurement.
Characterization of a Salmonella choleraesuis isolate after repeated neutrophil exposure
Authors: Roof Michael B. , Kramer Theodore T. , Roth James A. , Minion F. Chris
Published: January 2024

Salmonella choleraesuis strain 38 (glycerol-positive fermentation) was repeatedly exposed to porcine neutrophils in an attempt to mimic in vivo conditions of the host immune system. After phagocytosis, viable intracellular S choleraesuis were isolated and the process was repeated at least 5 times. A fifth-passage strain-38 neutrophil-adapted clone, 38PMNa-5X, was isolated, and was compared with the parent wild-type strain 38 for changes. Strain 38PMNa-5X had increased resistance to killing by hydrogen peroxide and phagocyte killing by porcine neutrophils, as measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction. Strain 38PMNa-5X was less invasive than the parent strain on Vero cell monolayers, and had been cured of a 50-kb plasmid. The 50-kb plasmid was marked with bacteriophage mini-Mu (kanamycin resistant) and was reinserted into strain 38PMNa-5X. Strain 38PMNa-5X was avirulent in mice, but the isolates with reinserted plasmids had intermediate resistance to neutrophil and hydrogen peroxide killing and had restored invasiveness and mouse virulence. Differences in complement sensitivity and enzymatic activity were not observed between the strains.
Effects of triiodothyronine treatment on pharmacokinetic properties and metabolite formation of antipyrine in dwarf goats
Authors: Offiah Veronica N. , Nijmeijer Sandra M. , van Duin Cock T. M. , Witkamp Renger F. , van Miert Adelbert S. J. P. A. M.
Published: January 2024

The influence of triiodothyronine (5 μg/kg of body weight, sc, q 12 h for 7 days) on antipyrine (ap, 25 mg/kg, iv) plasma elimination and urinary metabolite excretion was studied in castrated male dwarf goats. After triiodothyronine treatment, a significant increase in ap elimination was found. However, the observed changes in clearances for production of ap metabolites (nor-ap, 3-hydroxymethyl-ap; 4-hydroxy-ap, and 4,4′-dihydroxy-ap) do not suggest a clear selectivity of triiodothyronine toward any of the metabolic pathways of ap.
Evaluation of hemorheologic variables as implications for exercise-induced pulmonary hemorrhage in racing Thoroughbreds
Authors: McClay Carolyn B. , Weiss Douglas J. , Smith Clark M. , Gordon Brad
Published: January 2024

Hematologic and rheologic changes were examined in 49 Thoroughbreds before and after competitive racing. Mean postrace values for rbc count, hemoglobin concentration, and pcv increased by 58 to 61%, whereas blood viscosity increased 2 to 3 times. Postrace echinocyte numbers were 162% greater than prerace values. Smaller, but statistically significant, changes were found for mean corpuscular hemoglobin concentration, red cell distribution width, plasma total protein concentration, total wbc count, neutrophil count, and lymphocyte count. Variables measured did not predict whether a horse was a bleeder not treated with furosemide, a bleeder treated with furosemide, or a nonbleeder.
Effects of split-thickness and full-thickness skin grafts on secondary graft contraction in horses
Authors: Ford Troy S. , Schumacher J , Brumbaugh Gordon W. , Honnas Clifford M.
Published: January 2024

Full-thickness, circular (4-cm diameter) cutaneous wounds were created on the metacarpi and metatarsi of 6 horses. Immediately after wounding, 1 wound on each horse received a meshed, split-thickness skin graft (0.64 mm) obtained from the ventrolateral aspect of the horse's thorax by use of a pneumatic dermatome, whereas a second wound received a meshed, full-thickness skin graft obtained from the pectoral area. In addition, sections of split-thickness and full-thickness grafts were refrigerated in a solution of McCoy's 5A medium, to which equine serum (10%) and gentamicin sulfate solution (16 mg/dl) were added. Ten days after wounding, 1 granulating wound on each horse was grafted with a stored, meshed, split-thickness graft, and 1 granulating wound on each horse was grafted with a stored, meshed, full-thickness graft.

Areas of wounds were calculated from photographs taken of wounds on days 1, 5, 10, 15, 20, 25, and 30 after wounding. Time course of contraction was determined by use of a first-order mathematic model of changes in area through time.

Rate constants of contraction for fresh or granulating wounds receiving full-thickness grafts did not differ signficantly from those for fresh or granulating wounds receiving split-thickness grafts. Rate constants of contraction for grafted fresh wounds, however, were significantly less than those of grafted granulating wounds, regardless of whether a split-thickness or full-thickness graft was applied.
Epidermal growth factor-like activity in mares’ milk
Authors: Murray Michael J. , Schaudies R. Paul , Cavey D. Michael
Published: January 2024

Epidermal growth factor (egf)-like activity was measured in mares’ colostrum and milk by radioreceptor assay. Milk samples were collected from 22 mares 1 or more times during early lactation. Samples of colostrum were taken after parturition and before the foal first suckled (presuckle), within 6 hours after the foal first suckled (postsuckle), and on days 1, 2, 4, and 8 of lactation. In the 5 mares from which milk samples were obtained at each sampling time, presuckle colostral mean egf-like activity (17.8 ng/ml) was greatest (P < 0.05). The mean values for egf-like activity at all other sampling times were not significantly different from each other (postsuckle colostrum, 9.7 ng/ml; day 1, 9.6 ng/ml; day 2, 8.5 ng/ml; day 4, 8.0 ng/ml; day 8, 7.8 ng/ml).
Characterization of erythrocytic indices and serum iron values in healthy llamas
Authors: Weiser M. G. , Fettman M. J. , Van Houten D. , Johnson L. , Garry F.
Published: January 2024

An electronic particle counter with attached particle-size analyzer was configured to directly determine concentration, mean cell volume, and volume distribution of erythrocytes in llama blood. Blood from 38 healthy llamas was used to characterize erythrocytic measurements and serum iron values for this species. Volume distribution curves for llama erythrocytes were similar in shape to those of other species. These curves had a unimodal, symmetric shape with a tail skewed to the right. Reference ranges for directly measured mean cell volume, erythrocyte concentration, hemoglobin concentration, and mean cell hemoglobin concentration were 21 to 28 fl, 11.3 × to 17.5 × 106 cells/μl, 12.8 to 17.6 g/dl, and 43.2 to 46.6 g/dl, respectively. Reference ranges for serum iron concentration, total iron-binding capacity, and transferrin saturation were determined to be 70 to 148 μg/dl, 230 to 370 μg/dl, and 22 to 50%, respectively.
Effect of protein source in liquid formula diets on food intake, physiologic values, and growth of equine neonates
Authors: Buffington C. A. Tony , Knight D. A. , Kohn C. W. , Madigan J. E. , Scaman P. A.
Published: January 2024

The effects of 2 liquid formula diets differing in protein source were evaluated in orphan foals. The response of 7 foals fed a diet containing casein as the protein source, and 6 foals fed a diet containing a combination of whey and casein, was compared with the response in a reference group of 8 mare-raised foals. Orphaned foals were fed 150 kcal/kg of body weight/d, divided into 6 equal feedings of 25 kcal/kg. Formula intake was comparable among the experimental groups, and foals fed the liquid formula diet grew as well as mare-raised foals. There was no difference among groups in mean daily body weight gain, wither height, heart girth, body temperature, pulse, respiration rate, capillary refill time, or skin tenting. Insulin and blood glucose concentrations increased in both groups of foals fed formula diets, returning to prefeeding values within 4 hours. Differences among groups were found for serum alkaline phosphatase, alanine transaminase, cholesterol, creatinine, and glucose values; all other serum chemical values were comparable among groups. Plasma amino acid determinations revealed that arginine and ornithine were significantly lower in foals in both experimental groups than in reference foals, suggesting that arginine may have been the limiting amino acid in these diets. Diarrhea developed in foals in all treatment groups, but in most cases was self-limiting. These results suggest that the protein source of liquid formula diets may be less important in foals than in infants.
Composition and analysis of cerebrospinal fluid in clinically normal adult cattle
Authors: Welles Elizabeth G. , Tyler Jeff W. , Sorjonen Don C. , Whatley Elizabeth M.
Published: January 2024

Cerebrospinal fluid and serum were obtained from 16 clinically normal adult cows (11 dairy, 5 beef). Sodium, potassium, magnesium, total protein, and albumin concentrations, osmolality, and lactate dehydrogenase and creatine kinase activities, were quantified in csf and serum. Total and differential cell counting, protein electrophoresis, and IgG quantification were performed on csf. Statistical analyses of these variables, including mean, sem, range, and 95% confidence intervals, were performed. Effects of blood contamination were evaluated, and were found to be negligible for all measured constituents. Correction factors for csf creatine kinase and lactate dehydrogenase activities accounting for cellular contamination were developed.

Total nucleated cell count was similar to counts in csf of other species, but higher than values in healthy people. Differential leukocyte count in csf was similar to that reported in csf of other domestic animals: mostly lymphocytes, fewer monocytoid cells, and scant neutrophils.

Cerebrospinal fluid protein concentration was higher than concentration reported for dogs, goats, and people, but was similar to values reported for horses. Beef cows had higher csf total protein concentration than did dairy cows; also, beef cows had higher csf γ-globulin concentration.

The concentration of sodium in csf was slightly higher than the value in serum, and potassium concentration was lower than the value in serum. In contrast to studies of human beings, csf osmolality was generally less than serum osmolality in the cows studied. Reference values for csf electrolyte concentrations and osmolality are useful for diagnosis of salt poisoning and for assessment of the effects of fluid therapy. Magnesium concentration was lower in csf, compared with serum. Reference values may be useful for diagnosis of grass tetany.

Glucose concentration in csf was variable, compared with serum concentration; sometimes, it was similar, lower, or even higher than serum glucose concentration. This variation reflects a more complete equilibration of glucose between csf and blood, owing to the lower and more stable blood glucose concentration in cows.

Creatine kinase activity in csf was markedly less than, and was not correlated with, serum creatine kinase activity. Cerebrospinal fluid lactate dehydrogenase activity was markedly lower than serum lactate dehydrogenase activity. Compared with lactate dehydrogenase, creatine kinase activity had a wider range in these healthy cows; therefore, the former enzyme has higher specificity and sensitivity for diagnosis of diseases affecting the cns.
Ultrasonographic and quantitative histologic assessment of sequelae to testicular biopsy in stallions
Authors: DelVento V. R. , Amann R. P. , Trotter G. W. , Veeramachaneni D. N. Rao , Squires E. L.
Published: January 2024

A sample of testicular parenchymal tissue, approximately 2 × 7 × 7 mm, was aseptically removed from 1 testis in each of 9 stallions on day 0. Slight to moderate hemorrhage from the tunica albuginea was observed in 8 stallions, but bleeding from the parenchyma was detected in only 2 stallions. Stallions were castrated 27 days later. Normal development of granulation tissue was evident at the biopsy site, but hematomas were not observed. In situ measurement of the widths of the right and left testes, total scrotal width, and evaluation of testicular echogenicity during ultrasonography were variables used to monitor changes in the testicular parenchyma from 14 days before biopsy through 27 days after biopsy.

The control testis was consistently larger than the biopsied testis, except for day 3. Ultrasonography revealed signs of a localized change in the parenchyma of the biopsied testis in 4 stallions, but each lesion decreased in size by day 27. Tissues removed during biopsy enabled an excellent appraisal of spermatogenesis at that time. Detailed examinations of seminiferous tubules in the testes were performed to assess for damage to testicular function. At castration, samples were taken from 6 sites in each testis. Quantitative histologic evaluations of testicular tissues revealed low numbers of spherical spermatids and pachytene spermatocytes in biopsied testes, compared with control testes.

It was concluded that there was a transitory increase in degeneration of preleptotene spermatocytes and B spermatogonia at the time of biopsy. A mild inflammatory response at the biopsy site in some testes was evidenced by an increased number of leukocytes at the biopsy site and at a dorsal site. Because damage was minimal and appeared to be transitory, it was concluded that the open method of biopsy does not greatly alter the process of spermatogenesis or function of the testis in stallions.
Development of enzyme-linked immunosorbent assays for conglutinin, mannan-binding protein, and serum amyloid-P component in bovine sera
Authors: Akiyama Kazuo , Sugii Shunji , Hirota Yoshikazu
Published: January 2024

Sandwich elisa were developed to quantitatively determine conglutinin (cg), mannan-binding protein (mbp), and serum amyloid-P component (sap) in the sera of cattle. The elisa system was found to have high repeatability for quantitation of these serum proteins at concentration as low as 5 ng/ml. From results obtained for 10 healthy cows aged 2 to 7 years, mean ± sd serum concentrations were 56.5 ± 14.4 μg of cg/ml, 2.37 ± 0.87 μg of mbp/ml, and 11.14 ± 3.92 μg of sap/ml, respectively. Values in 6 healthy heifer calves aged 6 months were 3.45 ± 1.22 μg/ml for cg, 1.71 ± 0.96 μg/ml for mbp, and 5.45 ± 2.75 μg/ml for sap, respectively. Concentrations in 9 healthy bullocks aged 6 months were 1.83 ± 0.66 μg/ml for cg, 1.04 ± 0.63 μg/ml for mbp, and 4.9 ± 1.13 μg/ml for sap, respectively.
Diet and exercise as potential risk factors for osteochondritis dissecans in dogs
Authors: Slater Margaret R. , Scarlett Janet M. , Donoghue Susan , Kaderly Robert E. , Bonnett Brenda N. , Cockshutt Joanne , Erb Hollis N.
Published: January 2024

A matched case-control study was conducted to evaluate dietary components and exercise patterns as potential risk factors for osteochondritis dissecans in dogs. A telephone interview, with a standard questionnaire and protocol, was used to collect data on dietary intake of calories and nutrients and on the usual amounts and types of exercise of each dog. Thirty-one dogs with osteochondritis dissecans and 60 controls were matched on the basis of breed, sex, and age. Using a conditional logistic regression model, high dietary calcium, playing with other dogs, and drinking well water (rather than city water) were associated with increased risk of osteochondritis dissecans. Feeding of specialty dry dog foods was associated with decreased risk.
Cardiovascular and respiratory effects of propofol administration in hypovolemic dogs
Authors: Ilkiw Jan E. , Pascoe Peter J. , Haskins Steve C. , Patz John D.
Published: January 2024

Cardiopulmonary effects of propofol were studied in hypovolemic dogs from completion of, until 1 hour after administration. Hypovolemia was induced by withdrawal of blood from dogs until mean arterial pressure of 60 mm of Hg was achieved. After stabilization at this pressure for 1 hour, 6 mg of propofol/kg of body weight was administered iv to 7 dogs, and cardiopulmonary effects were measured. After blood withdrawal and prior to propofol administration, oxygen utilization ratio increased, whereas mean arterial pressure, mean pulmonary arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, oxygen delivery, mixed venous oxygen tension, and mixed venous oxygen content decreased from baseline. Three minutes after propofol administration, mean pulmonary arterial pressure, pulmonary vascular resistance, oxygen utilization ratio, venous admixture, and arterial and mixed venous carbon dioxide tensions increased, whereas mean arterial pressure, arterial oxygen tension, mixed venous oxygen content, arterial and mixed venous pH decreased from values measured prior to propofol administration. Fifteen minutes after propofol administration, mixed venous carbon dioxide tension was still increased; however by 30 minutes after propofol administration, all measurements had returned to values similar to those measured prior to propofol administration.
Effects of a fixed compression load on the osteogenic effect of autogenous cancellous bone grafts in dogs
Authors: Martinez Steven A. , Probst Curtis W. , Hauptman Joseph G. , Weisbrode Steven E.
Published: January 2024

A standardized cortical defect was created on the caudal cortex of the proximal portion of each ulna in 5 adult mixed-breed dogs. One gram of autogenous cancellous bone graft (acbg) was obtained from the greater tubercle of the ipsilateral humerus. The cortical defect in the ulna of 1 limb was filled with 1 g of acbg that had been compressed with 2-MPa pressure for 30 seconds. One gram of noncompressed acbg was placed into the contralateral ulnar cortical defect. The compressed and noncompressed acbg recipient sites were radiographed at weekly intervals. Dogs were euthanatized 8 weeks after surgery, and the acbg recipient sites were harvested for histomor-phometric analysis. Optical densitometry was performed on all radiographs. There was no significant difference between compressed and noncompressed acbg with optical densitometry or histomorphometric analysis for total bone area. We concluded that there was no difference in osteogenic capability between compressed and noncompressed acbg of equal mass.
Evaluation of polysaccharide, lipopolysaccharide, and β-glucan antigens in gel immunodiffusion tests for brucellosis in cattle
Authors: Lord Veronica R. , Cherwonogrodzky John W.
Published: January 2024

In Venezuela, 1,012 cattle sera were screened for their ability to precipitate Brucella melitensis 16M smooth-lipopolysaccharide (s-lps), B melitensis B115 polysaccharide B (poly B), B abortus 1119-3 O-polysaccharide (ps), or B abortus 1119-3 cyclic 1,2 linked β-d-glucan (β-glucan) in an agar-gel immunodiffusion assay. These sera were previously classified as being Brucella abortus-infected, S-19-vaccinated, or negative after an assessment of historical records and results of 5 standard serologic tests. Most of the sera (85%) from infected cattle precipitated s-lps, poly B, and ps. Serologic results for poly B and ps were identical. On the other hand, 13% of the sera from vaccinated cattle precipitated s-lps, but none of these sera precipitated poly B or ps. It was concluded that purified ps can alternate with poly B as an antigen to differentiate sera of B abortus-infected from B abortus S-19-vaccinated cattle. None of these sera precipitated β-glucan.
Canine bone shape analysis by use of a radiographic image-classification system
Authors: Zhu Dongping , Carrig Colin B. , Conners Richard W. , Swecker William S.
Published: January 2024

A radiographic image-classification system was developed to analyze and compare the shape of the humerus of neonatal Labrador Retriever and Labrador Retriever × Beagle pups that were either phenotypically normal or affected with an ocular-skeletal dysplasia syndrome. The system consistently defined the shape of the humerus within the groups of pups studied and indicated a difference in the shape of the humerus between normal and affected pups. Results indicated that the radiographic image-classification system may be able to identify Labrador Retriever pups affected by the ocular-skeletal dysplasia syndrome at or shortly after birth.
Quantitative renal scintigraphic determination of the glomerular filtration rate in cats with normal and abnormal kidney function, using 99mTc-diethylenetriaminepentaacetic acid
Authors: Uribe Daniel , Krawiec Donald R. , Twardock A. Robert , Gelberg Howard B.
Published: January 2024

The nuclear imaging technique known as quantitative renal scintigraphy was validated as a means to assess the kidney function of cats. Renal function tests were performed in 6 healthy cats and 3 cats with clinical manifestations of kidney failure. In addition, the nephrotoxic drugs, gentamicin sulfate, or amphotericin B were used in an attempt to induce renal failure in 4 cats. Using linear regression analysis, equations were derived to estimate the glomerular filtration rate (gfr) on the basis of the renal percent uptake of 99mTc-diethylenetriami-nepentaacetic acid (99mTc-dtpa). One-way anova and Student’s t test were used to evaluate treatment effects on clearances of inulin and creatinine, percent uptake of 99mTc-dtpa, and serum creatinine concentrations. The results show that the percent uptake of 99mTc-dtpa by the kidneys correlated well with the GFR obtained through the clearance of inulin. Thus, it was concluded that quantitative renal scintigraphy, using 99mTc-dtpa as a marker of kidney function, is an adequate technique to estimate the kidney function of healthy cats and cats with functional renal impairment. The best estimate of the gfr of cats, using the percentage dose of 99mTc-dtpa, was obtained on the 1- to 3-minute postinjection interval of the marker, using data that was background-subtracted, but not corrected for tissue absorption of gamma rays or binding of 99mTc-DTPA to plasma proteins. There was no significant difference in the mean inulin clearance, creatinine clearance, or percent uptake of 99mTc-dtpa between the 3 treatment groups of this study. Therefore, it was concluded that neither gentamicin nor amphotericin B are useful drugs in eliciting losses of feline kidney function that may be measurable through the procedures used in this study. Contrary to all other gfr studies in the cat, this study did not use any form of pharmacologic restraint. Therefore, the findings from this study are expected to reflect accurately the true gfr of healthy, nonanesthetized cats.
Stimulation and suppression of the oxygenation activity of porcine pulmonary alveolar macrophages by Actinobacillus pleuropneumoniae and its metabolites
Authors: Dom P. , Haesebrouck F. , De Baetselier P.
Published: January 2024

The effects of Actinobacillus (Haemophilus) pleuro-pneumoniae and its metabolites on the oxygenation activity of porcine pulmonary alveolar macrophages (pam) were studied, using a chemiluminescence technique. Actinobacillus pleuropneumoniae strains of serotypes 2, 3, and 9 in a dose of 1, 10, and 100 colony-forming units/ macrophage first stimulated the oxygen radical production of pam. After having reached a peak value, oxygenation activity decreased, finally resulting in total suppression of pam. All these effects were neutralized by homologous convalescent pig sera that had been adsorbed onto inactivated A pleuropneumoniae strains. Moreover, cross-neutralization was shown between serotypes 2 and 3. Inactivated A pleuropneumoniae strains did not influence the oxidative activity of pam. Undiluted and lower dilutions of sterile A pleuropneumoniae culture supernatants were toxic for pam, whereas higher dilutions of the supernatants stimulated oxygen radical production of the macrophages. These effects were heat-sensitive and were neutralized by homologous convalescent pig sera. Cross-neutralization was shown between serotypes 2 and 3. These findings indicated that stimulation and inhibition of the oxygenation activity of pam are attributable to heat-sensitive metabolites produced by A pleuropneumoniae.
Intestinal permeability in pigs during rotavirus infection
Authors: Vellenga Liebe , Egberts Herman J. A. , Wensing Theo , van Dijk Jaap E. , Mouwen Johan M. V. M. , Breukink Henk J.
Published: January 2024

Macromolecular permeability of the small intestine was tested in four 3-week-old gnotobiotic pigs inoculated with porcine rotavirus strain RV277 (group A). Pigs were administered 126I-labeled polyvinylpyrrolidone (molecular weight [mol wt], 40,000) orally 1 day before and 2 and 24 hours after virus inoculation, and blood samples were obtained every 6 hours. Eight hours after rotavirus inoculation, pigs had watery diarrhea. Increased permeation of 125I-labeled polyvinylpyrrolidone was not observed after clinical signs of infection had developed. Serum total protein and urea nitrogen concentrations increased slightly at the end of the study, probably as a consequence of dehydration. Differences in blood glucose concentration were not seen. At 48 hours after viral inoculation, macromolecular permeability was tested morphologically by injecting horseradish peroxidase (mol wt, 40,000) into the jejunal lumen just distally to the ligamentum colicoduo-denale. After am incubation period of 20 minutes, small segments of jejunum were obtained for stereomicroscopic, histologic, and ultrastructural investigations. Moderate hyperregenerative villus atrophy was found. Ultrastructural changes of the villus epithelium were minor, and increased macromolecular permeation was not observed.
Evaluation of support bandaging during measurement of proximal sesamoidean ligament strain in horses by use of a mercury strain gauge
Authors: Keegan Kevin G. , Baker Gordon J. , Boero Michael J. , Pijanowski Gerry J. , Phillips Jim W.
Published: January 2024

Liquid mercury strain gauges were implanted in the forelimb proximal sesamoidean ligaments (psl) of 8 adult horses. The gauges measured psl strain while horses were standing with or without external support. In 6 of the horses, the gauges also measured PSL strain in horses at a walk, with or without external support. Gauges were enclosed within sliding polypropylene tubes to prevent nonaxial deformation. Each gauge was placed in 1 arm of a low-resistance half-bridge circuit. To provide temperature compensation, a dummy gauge was placed in the adjacent arm of the bridge circuit and was implanted next to the active gauge in the surrounding fascial tissue.

External support included fiberglass cast support (cast), dorsal fetlock splint support (dfs), support wraps of 3 bandage materials (SW1, SW2, and SW3), and support wrap with caudal splint (SW4). The cast was applied, with the fetlock and foot in weightbearing position, from the proximal portion of the metacarpus distal to and including the foot. The dfs was applied by placing the cranial half of the fiberglass cast on the dorsal aspect of the instrumented limb. The SW1, SW2, and SW3 were applied in a figure-8 pattern around the fetlock, using 50% of the linear stretch capacity of the bandage material, with the horse standing squarely on all 4 limbs. The SW4 was applied identically to the other support wraps, with the exception of addition of a flexible caudal splint incorporated in the support wrap.

Mean maximal strain while standing (∈s) without external support for 8 horses was 6.0% (range, 3.8 to 7.5%). Mean maximal strain at a walk (∈s) without external support for 6 horses was 5.9% (range, 4.1 to 8.2%). Only cast and dfs significantly reduced ∈s. Cast support reduced ∈s to a mean ± SEM 1.4 ± 0.2%, 77% reduction in total strain (P <0.0001). Use of dfs reduced ∈s to a mean 4.2 ± 0.3%, 30% reduction in total strain (P < 0.0001). The SW1, SW2, and SW3 did not significantly reduce ∈s (power > 0.8, δ = 20%). Conclusions cannot be made for reduction of ∈s with SW4 (power < 0.8, δ = 20%) because of low sample size. Only cast and dfs significantly reduced ∈w. Cast support reduced ∈w to a mean 2.0 ± 0.3%, 67% reduction in total strain (P < 0.0001). The dfs reduced ∈w to a mean 4.4 ± 0.4%, 25% reduction in total strain (P < 0.008). The SW1, SW2, and SW3 did not significantly reduce ∈w (power > 0.8, ∂ = 20%). Conclusions cannot be made for reduction of ∈w with SW4 (power < 0.8, ∂ = 20%) because of low sample size.
Serodiagnosis of paratuberculosis in sheep by use of agar gel immunodiffusion
Authors: Shulaw W. P. , Bech-Nielsen S. , Rings D. M. , Getzy D. M. , Woodruff T. S.
Published: January 2024

An agar gel immunodiffusion (agid) test was used over a 3-year period to examine 1,871 serum samples from sheep representing 5 Mycobacterium paratuberculosis — infected flocks and 4 flocks presumed to be uninfected. Of 1,032 sheep, 31 had positive agid test results (scoring 1 to 5), and 23 of these 31 were necropsied. Infection with M paratuberculosis was confirmed by 1 or more of the following findings: observation of typical lesions on histologic examination of sections of ileum or ileocecal lymph nodes, observation of clumps of acid-fast bacteria in mucosal smears of ileum, and isolation of the organism from feces or tissue. False-positive results on agid testing were not found in sheep from flocks known to have exposure to Corynebacterium pseudotuberculosis. Diarrhea in infected sheep was observed infrequently; chronic, severe weight loss was the most common sign observed. On histologic examination of tissues from 20 infected sheep, 16 (80%) had diffuse lesions of the ileum and 13 (65%) had acid-fast bacteria in areas of ileal inflammation; 4 had discrete granulomas and peripheral lymphocytic infiltrates in the ileum. Sheep with diffuse lesions tended to have higher mean scores on agid testing and examination for acid-fast bacteria, compared with those from sheep with more discrete lesions. Bacteriologic culture yielded M paratuberculosis from only 3 sheep with paratuberculosis. On the basis of results of this study, we suggest that the nature of the response to infection with M paratuberculosis may influence the results of diagnostic tests for paratuberculosis, and that agid testing may be useful to identify M paratuberculosis infection in sheep with chronic weight loss and in flock-screening programs.
Technique for long-term right dorsal colon fistulization in ponies
Authors: Wilkins Pamela A. , Lowe John E.
Published: January 2024

Right dorsal colon fistulas, 2.5 cm in diameter, were created in 2 healthy ponies, using a 2-stage surgical procedure. The first stage consisted of resection of portions of the 16th and 17th ribs on the right side, followed by surgical creation of a 6- to 8-cm-diameter adhesion between the right dorsal colon and the body wall. Fistulas were created approximately 2 weeks after the first surgery by sharp dissection through the adhesion into the lumen of the colon. The fistulas have been satisfactorily maintained for > 2 years by de Pezzer catheters (45 F). Ponies with fistulas have been used for gastrointestinal experiments.
Cytokine production during endotoxin-induced mastitis in lactating dairy cows
Authors: Shuster Dale E. , Kehrli Marcus E. , Stevens Mark G.
Published: January 2024

The role of interleukin-1 (il-1), interleukin-6 (il- 6), and tumor necrosis factor α during endotoxin-induced mastitis in cows was characterized. Six cows had 10 μg of Escherichia coli lipopolysaccharide infused into 1 mammary gland. Three other cows served as nontreated controls. Within 1.5 to 2.5 hours after infusion, endotoxin caused obvious edema of the mammary gland and increased serum albumin concentration in milk of infused glands 6 times. Milk somatic cell count began to increase 3 to 5 hours after infusion in all treated glands. At 7 hours after infusion, somatic cell counts were increased >10 times, compared with counts in milk from control cows. Pyrexia of >1 C developed in only 1 cow, but all treated cows had serum cortisol concentrations >50 ng/ml in response to endotoxin treatment. High concentrations of il-1 (10 to 600 U/ml) and il-6 (2 to 22 U/ml) were detected in milk of infused glands beginning 2.5 to 4 hours after infusion. Endotoxin did not induce detectable amounts of tumor necrosis factor activity in milk or serum. Swelling and mammary gland permeability changes preceded any detectable increase in il-1 and il-6 activity, indicating that these clinical signs of inflammation were not mediated by these cytokines. Systemic responses and the leukocytic influx into endotoxin-infused glands developed after or concurrently with initial increases in il-1 and il-6 activities in milk. These results suggested that il-1 and il-6 may have a role in mammary gland defenses and in the pathophysiologic changes during endotoxin-induced mastitis.