Collection of a satisfactory blood sample requires special procedures to prevent changes in glucose and lactate content after the sample has been obtained. Changes in measured plasma glucose and blood lactate concentrations attributable to anticoagulants and storage procedures, respectively, were examined in blood samples obtained from horses at rest and after exercise. To evaluate the effect of anticoagulants on measured plasma glucose concentration, blood was preserved with either sodium fluoride/potassium oxalate or lithium heparin. Measured plasma glucose concentration in blood obtained at rest and after exercise was 6 and 10% lower (P = 0.0038), respectively, when blood was preserved with fluoride/oxalate, compared with heparin. The erythrocyte volume in the blood sample was 15% smaller (P = 0.0001) in samples preserved with fluoride/oxalate, indicating a movement of water out of erythrocytes in the blood sample mixed with that anticoagulant. To evaluate the effect of storage procedure on measured blood lactate concentration, part of the blood sample was immediately deproteinized for blood lactate analysis, and the remaining blood was maintained for 30 and 60 minutes at either 0 or 22 C before deproteinization. When blood samples were maintained at 0 C prior to deproteinization, there was no difference in blood lactate concentration, regardless of the incubation time, compared with that in samples immediately deproteinized. Blood lactate concentration was greater (P < 0.01) in samples maintained at 22 C, compared with that in samples immediately deproteinized, and with that in equivalent samples maintained at 0 C. Blood preserved with fluoride/oxalate had lower measured plasma glucose concentration, compared with blood preserved with heparin, which was probably attributable to shrinkage of erythrocytes and dilution of the plasma with intracellular water. Minimal changes in blood lactate concentration were observed in samples maintained at 0 C up to 60 minutes.

Dynamics of plasma ferulenol concentration and its effect on the vitamin K-dependent coagulation factors, prothrombin time (PT), and activated partial thromboplastin time (APTT) were determined in 4 sheep intoxicated individually with 600 g of powdered Ferula communis variety brevifolia (FCb) given in 8 doses at intervals of 6 hours. Ferulenol was detected in the plasma of all sheep at initial blood sample collection, 6 hours after the first dose of approximately 75 g of FCb was placed in the rumen. The last observed peak of approximately 20 microgram/ml was detected at about 12 hours after the last of 8 doses, and the mean concentration then decreased to < 1 microgram/ml during the next 70 hours. Maximal concentration of ferulenol and time for plasma clearance varied with individual sheep. The PT increased steadily to a maximum of 6 times normal about 70 hours after the last peak plasma ferulenol concentration and about 80 hours after FCb administration was stopped. The PT then retumed to almost normal (ratio of 1.12) from the maximum (ratio of 6.12) within approximately 5 days. The APTT results gnerally paralleled the PT results, but the change was not as marked. Maximal PT and APTT ratios were animal-dependent and not always related to plasma ferulenol concentration. The activity of all the vitamin K-dependent coagulation factors was depressed, but the variations were unique to each factor. Factor V, a vitamin K-independent coagulation factor actually had a brief period of increased plasma activity. We concluded that the effects on PT, APTT, and vitarnin K-dependent coagulation factors induced in sheep intoxicated with FCb were consistent with the coumarinic structure of ferulenol, the intoxicating compound in FCb, which seems to have a short-term anticoagulation effect.

Bronchoalveolar lavage (BAL) was performed on 16 horses to determine whether it caused local or diffuse inflammation in the lungs. In 7 horses, BAL was performed in both lungs twice, 48 hours apart. Although total cell counts of the BAL samples did not change significantly, there were increased numbers and percentage of neutrophils in the second lavage fluid samples. In 5 horses, BAL was performed in 1 lung and repeated 48 hours later in the same lung and in the corresponding airway in the contralateral lung. The absolute cell count and percentage of neutrophils were significantly (P = < 0.05) increased in the second sample from the lung that was lavaged twice. In 4 horses, BAL was performed in 1 lung and 48 hours later, repeated in an adjacent airway to the first BAL site, and in the corresponding airway in the contralateral lung. Significant differences were not detected in the total or differential cell counts of the BAL fluid recovered at any time, except for an increase in neutrophil percentage in the second sample in the contralateral lung. The increased neutrophil percentage values were within the range of normal for healthy horses. Results of the study suggested that, in horses, BAL induces a localized pulmonary neutrophil influx that persists at least 48 hours and is characterized by a relative and absolute increase in the number of neutrophils in the lavage fluids.

An ELISA was developed to detect antibodies to the 41-kd flagellin (P41) of Borrelia burgdorferi in serum obtained from cattle. Absorption studies, immunoblot analysis, immunoelectron microscopy, and correlation of results of the P41-ELISA and the P39-ELISA as well as measurement of the antibody to P41 in calves challenge-exposed with Borrelia theileri were used to assess the specificity of the P41-ELISA. Antigens derived from Escherichia coli, Leptospira interrogans serovar hardjo, and B burgdorferi were used for absorption studies and immunoblot analysis. Antibodies to P41 of B burgdorferi cross-reacted with antigens of E coli, but were not cross-reactive with L hardjo. A value 3 SD higher than the mean of the negative-control population of cattle was defined as the minimum value cutoff value) for a positive result by the P41-ELISA. Use of this value for classification of test results reduced the predicted rate of false-positive results attributable to E coli cross-reactivity to 1%. Immunoblot analysis revealed that test-positive serum from cattle reacted mainly with 41-, 39-, 34-, and 31-kd proteins of B burgdorferi, as well as several smaller proteins. Immunoelectron microscopy revealed that serum from cattle that was test-positive by the P41-ELISA bound to the flagellin and outer membrane of B burgdorferi. Results of absorption studies, immunoblot analysis, and immunoelectron microscopy were correlated and indicated that serum from cattle that was test-positive by P41-ELISA had stronger reactivity to B burgdorferi antigens than to antigens of E coli or L hardjo. The concentrations of antibodies measured by P41-ELISA and P39-ELISA testing were highly correlated [R(2)=0.78]. Calves challenge-exposed with B theileri also had test-positive results by the P-41-ELISA as early as 2 weeks after exposure, but serum antibody concentrations decreased to prechallenge-exposure concentrations by 9 weeks after exposure. We concluded that the P41-ELISA was useful as a screening method to detect B burgdorferi infections in cattle.

An ELISA, using purified flagellin of Borrelia burgdorferi as the solid-phase antigen, was used to measure antibody concentrations to B burgdorferi in dairy cattle in Wisconsin. Serum obtained from 5,060 cows in 160 randomly selected herds in the state were tested. Serum from an additional 2,600 cattle in Barron County, Wis, a county with a high annual incidence of B burgdorferi infections in human beings, was also tested. Only 7% of the cows that were tested, but 66% of the herds that were tested, were seropositive for B burgdorferi. Sixteen percent of the herds had a prevalence of 15% seropositive cows, whereas 50% of the herds had a prevalence of 1 to 14% seropositive cows. Seropositive herds were concentrated in the west-central part of Wisconsin. An association existed between the geographic location of seropositive herds and counties in which B burgdorferi infection of human beings was acquired (P < 0.05) as well as the geographic location of seropositive herds and the geographic distribution of Ixodes scapularis (P < 0.05). Barron County, in which B burgdorferi infection is endemic, had a significantly (P < 0.05) higher percentage of seropositive cows (17%) than did the state of Wisconsin (7%).

Force platform analysis of gait provides ground reaction force information that can be used to study limbs with normal or abnormal function. When combined, the interrelated variables of ground reaction forces give a more thorough description of gait than when used individually. To describe the pattern of ground reaction forces in clinically normal, conditioned, mesomorphic dogs, we studied the data from platform gait analyses of 43 dogs. Mediolateral (Fx), craniocaudal (Fy), and vertical (Fz) forces were measured and recorded. Torque (Tz) around the vertical axis also was calculated. Mean stance times for forelimbs and hind limbs were 0.278 and 0.261 second, respectively. Among dogs, ground reaction forces were normalized and expressed as percentage of body weight (%bw). The vertical (Fz) peak, average force during stance phase, and force vs time impulses were 106.68, 60.82, and 17.2 %bw in forelimbs, and were 65.11, 35.3, and 9.33 %bw in hind limbs. The forelimb braking/ propulsive (Fy) peaks were -16.74 and +6,73 %bw. In hind limbs, these peaks were -3.76 and +7.69 %bw. The usual mediolateral force (Fx) pattern found in forelimbs was laterally directed, with average peak magnitude of 6.69 %bw, whereas the hind limb patterns were variable.

Pharmacokinetics and toxicity of a single dose of doxorubicin, at dosages of 30 mg/m2 of body surface area and 1 mg/kg of body weight, were compared in 17 dogs. Effects of doxorubicin on complete blood cell count, platelet count, and the dogs' clinical condition were evaluated for 14 days. Cluster analysis, on the basis of clinical signs of doxorubicin toxicosis at the 30-mg/m2 dosage, revealed that 6 of 7 small dogs (less than or equal to 10 kg) became ill, whereas 7 of 10 large dogs (> 10 kg) remained clinically normal. Small dogs that received doxorubicin at a dosage of 30 mg/m2 had higher peak plasma concentrations, greater area under the curve for plasma drug concentration vs time, longer drug elimination half-lives, greater volumes of distribution, and more clinical signs of toxicosis than had large dogs (P less than or equal to 0.05). Five of 9 small dogs that received doxorubicin at a dosage of 30 mg/m2 developed severe myelosuppression (< 1 X 103 granulocytes/microliter). In contrast to the toxicoses with body surface area-based dosing, myelosuppression was not induced in small dogs that received doxorubicin at a dosage of 1 mg/kg. In small and large dogs given doxorubicin at a dosage of 1 mg/kg, pharmacokinetic characteristics and clinical signs of toxicosis were similar. Mean WBC counts and granulocyte counts for all dogs were lower on day 7 with 30 mg of doxorubicin/ m2 (n = 17), compared with that for 1 mg of doxorubicin/kg (n = 14; P S 0.01). This study indicated that a body weight-based (milligram per kilogram) dosing regimen may result in more uniform therapeutic and toxic responses in dogs. Limited toxicosis was observed in dogs weighing > 10 kg treated with doxorubicin with either dosing scheme; however, differences in pharmacokinetic profiles suggested that 1 mg/kg may be an inappropriately low dosage.

A commercially available automated enzyme-multiplied immunoassay technique (EMIT) was used to determine serum caffeine concentration after oral and IV administrations of caffeine at dosage of 5 mg/ kg of body weight to 12 clinically normal dogs. Dogs were allotted to 2 groups of 6 dogs each; 1 group initially received caffeine orally and the other received caffeine IV. After 72 hours, caffeine administration was repeated in all dogs in the alternate manner. Serum samples were obtained at multiple intervals over 24 hours to determine distribution and elimination kinetics. Analysis of the drug concentration-time data indicated IV elimination half-life (t1/2) of 6.39 +/- 1.87 hours, volume of distribution at steady state of 685.3 +/- 132.2 ml/kg, total body clearance of 1.31 +/- 0.38 ml/min/kg, absorption t1/2 of 1.02 +/- 0.68 hour, oral elimination t1/2 of 6.53 +/ - 2.72 hours, lag time after oral administration of 0.0614 +/- 0.0661 hour, highest measured concentration of 5.29 +/- 1.17 micrograms/ml, time to peak concentration of 2.74 +/- 1.30 hours, and bioavailability of 99.4 +/- 19.4%. Data from 6 dogs best fit a 1-compartment open model and those from 6 other dogs best fit a 2-compartment open model. On the basis of data from the 6 dogs that best fit a 2-compartment model, t1/2 of distribution was 0.58 +/- 0.72 hour. Data for oral administration best fit a single absorption phase and a single elimination phase. The increased availability and simplicity of the EMIT offers an opportunity to study the application of caffeine elimination for clinical evaluation of dogs with liver disease. Data obtained from this study allow determination of t1/2 and clearance to be simplified by obtaining samples 4 and 8 hours after oral or IV administrations and establishes canine reference values for elimination kinetics of caffeine administered at dosage of 5 mg/kg and assayed by use of the EMIT.

The efficacy of 4-methylpyrazole (4-MP) and ethanol as treatment for ethylene glycol (EG) intoxication in cats was compared. Twenty-two cats were assigned at random to 6 experimental groups. Cats of 1 experimental group were given only 4-MP; those of another experimental group were given only EG. Cats of 3 experimental groups were intoxicated with EG and given 4-MP at 0 hour or 2 or 3 hours after EG ingestion, and those of 1 experimental group were given EG and treated with ethanol 3 hours after EG ingestion. Physical, biochemical, hematologic, blood gas, serum and urine EG concentrations, and urinalysis findings were evaluated at 0, 1, 3, 6, 9, 12, 24, 48, and 72 hours, 1 week, and 2 weeks after EG ingestion, or 4-MP treatment in cats of the 4-MP only group. The half-life of EG and percentage of ingested EG excreted unchanged were determined for each group. 4-Methylpyrazole treatment at 0 hour was most effective at preventing metabolism of EG. 4-Methylpyrazole was not effective in preventing development of renal failure when given 2 or 3 hours after EG ingestion. Ethanol given 3 hours after EG ingestion was successful in preventing development of renal dysfunction in 2 of the 6 cats treated 3 hours after EG ingestion. Of the remaining 4 cats treated with ethanol, 2 developed transient renal dysfunction and 2 developed acute oliguric renal failure and were euthanatized. 4-Methylpyrazol given 2 or 3 hours after EG ingestion was less effective in preventing EG metabolism than was ethanol given 3 hours after EG ingestion. Therefore 4-MP, at the dose found to be effective in dogs, cannot be recommended as an alternative to ethanol for treatment of EG intoxication in cats.

Five strains of Actinobacillus pleuropneumoniae serotype 1 were used to intranasally infect 5 groups of pigs. Using each bacterial strain, infected pigs (termed seeder pigs) were commingled for 48 hours with 5 groups of noninfected test pigs, then were removed. Seeder and test pigs were maintained in isolation and were observed for 14 days. Seeder pigs had mortality that was threefold greater than that of test pigs (24% vs 8%). Rectal temperature in excess of 40.3 C was achieved for 84% of test pigs and 88% of seeder pigs. Neither of these 2 variables was statistically different between the 2 groups of pigs. Clinical impression scores greater than or equal to 2 (on a 0 to 3 scale) were three-fold (64% vs 20%) greater for seeder than for test pigs (P < 0.05). The total number of bacterial isolations or nonrecoverable isolates was tabulated for test and seeder pigs' lungs at necropsy, irrespective of the amount of lesions. The number of A pleuropneumoniae isolations was not statistically different between test and seeder pig populations. Recovery of Pasteurella multocida or other bacteria was greater from the seeder pigs (P < 0.05), whereas the number of non-recoverable isolates was greater from test pigs than from seeder pigs (P < 0.05). Assessment of lung lesions at necropsy by either visual estimation or on a weight basis were in agreement. Fewer test pigs had lung lesions in excess of 5% of total lung volume than did seeder pigs (40% vs 84%) and, according to the odds ratio estimation, seeder pigs were 7 times more likely than test pigs to have such lesions. These results indicate a predictable, moderate intensity, natural exposure model for use in the study of Actinobacillus pleuropneumoniae-induced pneumonia. The seeder pig model appears to mimic field infection in development of clinical illness, febrile response, lung lesions, mortality, and low potential for secondary pneumonic bacterial involvement, thus providing a useful tool for preliminary evaluation of anti-infective modalities.