Genus-, subspecies-, and serotype 1-specific antigens of Chlamydia psittaci were characterized by immunoblot analysis, using monoclonal antibodies that recognize 2 C psittaci strains: AB7 isolated from an ewe that had aborted, and iB1 isolated from feces of a healthy ewe. Genus-specific epitopes were detected on lipopolysaccharide, on a 47-kd protein, and on a 27- to 30-kd doublet. Subspecies-specific epitopes were located on a 30-kd protein, and a 80- to 90-kd protein region was identified, which bore subspecies- and serotype 1-specific epitopes. These 80- to 90-kd proteins were highly reactive with serum from ewes that had aborted and could be a useful antigen for diagnosis of chlamydial induced abortion of ruminants.

The cause of species difference in the susceptibility of erythrocytes to L-sorbose, and the difference in the hemolytic effect of sorbose on high potassium-containing (HK) and low potassium-containing (LK) canine erythrocytes were examined. L-sorbose was phosphorylated in canine erythrocytes, but not in human erythrocytes. Furthermore, sorbose-1-phosphate, a metabolite of L-sorbose, strongly inhibited the hexokinase of LK canine erythrocytes, but not that of HK canine erythrocytes. These results strongly indicated that inhibition of hexokinase by sorbose-1-phosphate in LK erythrocytes induced severe glycolytic limitation in these cells, resulting in hemolysis, and that HK erythrocytes are resistant to sorbose-induced hemolysis because these cells have a high hexokinase activity.

To assess right colic artery blood flow and relevance of xanthine dehydrogenase/xanthine oxidase after experimentally induced strangulation obstruction and reperfusion of the colon, 5 ponies were subjected to 2.5 hours of complete ischemia of the left dorsal and ventral colons, allowed to recover from surgery, and monitored during a 48-hour reperfusion period. Five ponies were subjected to sham surgery and served as controls. All ponies had a Doppler ultrasound blood flow monitor implanted on the right colic artery near the pelvic flexure 10 to 14 days prior to the ischemic period. Colic artery blood flow was monitored prior to, during, and for 4 hours after surgery. Blood samples from the right colic artery and vein distal to the obstruction site were collected during surgery (prior to ischemia, after 1 and 2 hours of ischemia, and after 10 and 60 minutes of reperfusion) for determination of arterial and venous blood gas tensions and electrolytes. Prior to surgery, blood selenium and plasma vitamin E (alpha-tocopherol) concentrations and blood glutathione peroxidase (GPX) activity were determined to assess the status of endogenous antioxidants. Combined xanthine dehydrogenase (XDH) plus xanthine oxidase (XO) activity, and XO activity alone (nanomoles per minute per gram of tissue) were determined, using a dual-spectrophotometric technique. Xanthine dehydrogenase and oxidase activities were determined prior to ischemia, after 1 and 2 hours of ischemia, and at 1 and 48 hours after reperfusion. Median blood flow in the experimental and control groups (156 ml/min and 110 ml/min, respectively) was not statistically different before surgery, and was significantly (P < 0.02) lower in the experimental (4 ml/min) vs the control group (72.5 ml/min) during the ischemic period. Experimental ponies had significantly (P < 0.03) lower right colic artery blood flow during the 4 hours immediately after recovery from anesthesia. Significant difference was not observed in right colonic venous bicarbonate concentration between groups at any time. Median right colonic venous P(CO2), pH, and standard base excess were different (P < 0.001) between groups during the ischemic period only. Median venous oxygen saturation and median venous P(O2) were significantly (P < 0.001) lower in the experimental ponies at the end of 2 hours of ischemia, but were significantly (P < 0.05) increased during the reperfusion phase. Median venous potassium concentration was significantly (P < 0.01) higher in experimental ponies during the ischemic and reperfusion phases. Vitamin E and GPX values were within normal limits for all ponies. Median selenium concentration was < 15 microgram/dl; however, there were no significant differences between control and experimental ponies. Only 3 of 10 ponies had measurable XHH/XO activity at the beginning of the experiment. Enzyme activity was detected in 1 additional pony during the ischemic period. However, in all 4 ponies in which XDH/XO activity was detected, enzyme activity was low (10 to 36 nmol/min/g). On the basis of macroscopic and histologic examination of the large colon, evidence of reperfusion injury was not found in 4 of the 5 experimental ponies. The only pony with gross evidence of reperfusion injury did not have detectable XO activity. Results of the study indicate that hypoperfusion of the colon during the postischemic period may be a factor in deterioration of the colon observed clinically in equids with surgical correction of large-colon volvulus. Additionally, if reperfusion injury develops in the large colon, it probably is not mediated through the xanthine oxidase enzyme system: the activity of this enzyme in the large colon, when present, is negligible.

Bronchoalveolar lavage was performed through an endotracheal tube in 34 specific-pathogen-free cats to determine expected values for bronchoalveolar lavage fluid cytologic analysis, using this method of collection. Saline solution for lavage was instilled in 3 separate aliquots at a volume of 5 ml/kg of body weight each. Analysis of sequential aliquots was performed to investigate the differences in cell counts among the 3 fractions. The effect of combining aliquots, including or omitting the first fraction, was evaluated to determine whether all aliquots could be combined for analysis without substantially affecting results. The total number of nucleated cells retrieved from each cat ranged from 0.9 to 31.1 X 10(6). Most of these cells were macrophages (78 +/- 15%, mean +/- SD) and eosinophils (16 +/- 14%). The first aliquot had the greatest number of epithelial cells, and the lowest total nucleated cell count and relative and absolute eosinophil counts. Differences among aliquots also were identified for relative and absolute macrophage counts, relative and absolute neutrophil counts, and absolute lymphocyte count. Statistically significant differences were found for many of the cell counts when values from the combination of the second and third aliquots were compared with values from the combination of all 3 aliquots. Magnitude of the differences was small, and these differences were not believed to be of practical consequence.

Hepatobiliary scintigraphy provides a noninvasive assessment of hepatobiliary structure and function, and has been used extensively in people. Hepatocellular measurements determined in the cats of this study include cardiac washout (less than or equal to 2 minutes) and time of maximal hepatic activity (less than or equal to 5 minutes) and hepatic washout (less than or equal to 30 minutes). The gallbladder response to synthetic cholecystokinin was determined to be less than or equal to 3 minutes. Additional measurements also were identified. Potential use of hepatobiliary scintigraphy in feline medicine is discussed.

Equine endometria representative of Kenney's categories I, II, and III were incubated in vitro with phosphate buffer, Streptococcus pneumoniae, or S zooepidemicus. Endometrial tissues from mares in estrus and diestrus were first categorized according to Kenney's classification, then were tested for adherence of S pneumoniae and S zooepidemicus to the epithelia. Bacteria were not observed when the endometrial tissue was incubated with phosphate buffer or S pneumoniae. There was no statistical difference in attachment of S zooepidemicus to endometrial tissue from mares in estrus or diestrus if endometrial classification was ignored. However, bacterial attachment was significantly (P less than or equal to 0.05) higher in category III endometrium during estrus.

The consequences of inoculation of bluetongue virus (BTV) serotype 11 into 16 susceptible cows either at the time of breeding or at specified stages of pregnancy were studied. The cows were free of BTV or epizootic hemorrhagic disease virus, and none had antibodies to BTV before virus inoculation. A group of 4 cows was mated naturally to a bull reported to shed BTV (CO75B300 strain) in the semen. The bull was suspected of infecting cows at mating with BTV-11, which subsequently transplacentally infected the developing fetuses and induced persistently infected and congenitally malformed progeny. Two groups of 4 pregnant cows were inoculated with an insect-derived strain of BTV-11 (CO75B300), one group by direct deposit into the uterus at estrus, the other, by intradermal and sc administrations. A 90-day fetus was inoculated in utero with virus from the same pool. Four pregnant cows were inoculated with sheep blood-passaged virus of the same BTV-11 strain (CO75B300) by intradermal and sc routes. Three cows were inoculated with BTV-free suspending fluids and ovine erythrocytes by the intrauterine and intradermal-sc routes and were used as in-contact controls.Infection with insect-derived BTV-11 was confirmed in 3 cows of 1 group by virus isolation and by detection of serum antibodies. The 4 cows inoculated with sheep blood suspension of BTV-11 developed viremia and produced antibodies to the virus. None of the cattle had clinical signs of bluetongue, other than 2 cows that had a slight rectal temperature increase on postinoculation day 4.All cows and fetuses that ranged in gestational age from 69 to 217 days appeared grossly normal at necropsy. Antibodies were not detected in fetal blood. Viral antigen was not detected in fetal tissues by inoculation into sheep or by immunofluoerscence, and viral RNA was not detected by use of the polymerase chain reaction. Developmental deformities were not seen in any fetus. The BTV-11 was not transmitted via the bull semen after natural mating. The BTV-11 strain CO75B300, isolated from this bull and passaged either as insect-derived or ovine erythrocyte suspensions, infected 8 cows. However, the virus was not transplacentally transmitted to their fetuses. It was concluded that there was no evidence for congenital BTV-11 infection in this study.

Equine oxyntic mucosal cells were obtained by sequential exposure to pronase and collagenase. Acid production by parietal cells was assessed by uptake of [14C]aminopyrine (AP), a weak base that accumulates in intracellular acidic spaces. Incubation for various times revealed a maximal AP uptake at 10 minutes for histamine and carbachol. Similar secretagogue responses were observed for parietal cells from the mucosal cell preparation or after enrichment by elutriation. Histamine and isobutyl-methylxanthine (IBMX) stimulated AP uptake with a dose-dependent response and maximal effective concentration of 100 micromolar. Carbachol, 1 to 100 micromolar, and pentagastrin (PG), 1 to 1,000 nM, were ineffective stimulants of AP uptake. The AP uptake values for 100 micromolar IBMX, 1 micromolar carbachol, or 100 nM PG were 77 +/- 6%, 50 +/- 3.2%, and 40 +/- 4.5%, respectively, of that observed with maximal stimulation by 100 micromolar histamine (mean SEM, n = 4 to 14). Uptake of AP by nonstimulated control cells was 36 +/- 3.6% of maximal histamine stimulation. The AP accumulations during control conditions and after stimulation with 100 micromolar histamine and IBMX, 1 micromolar carbachol, or 100 nM PG were 1.18 +/- 0.39, 2.81 +/- 0.85, 1.93 +/- 0.48, 1.44 +/- 0.36, and 1.23 +/- 0.33 pmol of AP/10(5) parietal cells, respectively. Individual histamine dose-response curves were shifted to the right by increasing ranitidine and cimetidine concentrations (0.1 to 50 micromolar). These results indicate that isolated equine parietal cells are maximally stimulated by histamine and minimally stimulated by carbachol and PG.

Clinical trials have shown that currently available commercial vaccines against porcine pleuropneumonia provide inconsistent, serotype-specific protection from the disease. Recovery from naturally acquired infection, however, provides solid, serotype crossprotective immunity. We examined various serum responses of pigs receiving 1 of 4 commercial vaccines or a cell extract, and compared the serologic responses of these pigs after challenge exposure with virulent Actinobacillus pleuropneumoniae serotype 1. Evaluation of serum included complement-mediated killing opsonizing capacity, IgG titers to whole organisms, and cytotoxin neutralization titers. Pigs that received the cell extract had fewer clinical signs of pleuropneumonia than pigs in other vaccinated groups, and also were significantly (P < 0.05) better protected from development of lung lesions and death. Such vaccinates were the only pigs that developed significant (P < 0.05) serum antibody titers (ie, protective immune response) to whole-cell antigens and to cytotoxin.

Effects of 2 drugs commonly used for chemical restraint of cattle were evaluated for their effect on laryngeal and pharyngeal anatomy, function, and response to stimuli. Eighteen adult Jersey cows, free of respiratory tract disease, were studied. Cows were assigned at random to 1 of 3 treatment groups. Endoscopic evaluations were performed before and at a predetermined time interval after administration of each drug. Responses to stimuli were evaluated by stimulating 7 preselected sites (epiglottis, left and right arytenoid cartilages, left and right vocal folds, and left and right dorsolateral pharyngeal walls) with a closed, transendoscopic biopsy probe. Xylazine HCl (0.05 mg/kg of body weight, IV) was administered to group-1 cows (n = 6), and endoscopy was repeated 5 minutes after administration of the drug. Xylazine (0.07 mg/kg, IV) was administered to group-2 cows (n = 6), and endoscopy was repeated 5 minutes after administration of the drug. Acepromazine maleate (0.035 mg/kg, iv) was administered to group-3 cows (n = 6), and endoscopy was repeated 10 minutes after administration of the drug. Responses to stimuli were scored as brisk (0), moderate (1), slow (2), and absent (3). Scores for responses to stimuli were compared, using the Wilcoxon signed-rank test for data within groups, and a general linear models procedure, using the Kruskal-Wallis test between groups. Interobserver agreement rates were generated for each group. A value of P<0.05 was considered significant. Xylazine profoundly changed laryngeal sensitivity and function at both dosages. The corniculate processes of the arytenoid cartilages were observed to be in a markedly adducted position after sedation. Response to stimuli was significantly (P = 0.03) slower than normal after sedation, using both dosages. Displacement of the soft palate dorsal to the epiglottis was persistent in 50% of the cows after stimulation tests subsequent to sedation with xylazine. Acepromazine had a mild effect on laryngeal sensitivity and function. The corniculate processes of the arytenoid cartilages were observed in paramedian position after sedation. Acepromazine did not significantly affect responses to stimuli. Effects of sedation on responses to stimuli were not significantly different for groups 1 and 2. However, effects for group 3 were significantly different from those for groups 1 and 2 (P = 0.006 and 0.004, respectively). Endoscopic evaluation of the proximal portion of the respiratory tract of cattle should be performed without sedation, when possible. If sedation is required to facilitate restraint for endoscopy, acepromazine maleate is recommended over xylazine on the basis of results of this study.