Immunoglobulin E is produced in response to parasitic nematodes that undergo blood and tissue migrations. Results of our previous studies indicated that IgE and IgG respond to Dirofilaria immitis in experimentally infected dogs. To determine the association between treatment with the larvicide, diethylcarbamazine (DEC), and antibody responses and to examine the potential influence of infection with a nonfilarid intestinal nematode on isotype-specific immune responses, we monitored, by use of isotype-specific ELISA, separate IgE and IgG responses against D immitis in 4 groups (A-D) of 8 dogs experimentally coinfected with D immitis and Ancylostoma caninum. All dogs were monitored from 2 weeks before inoculation with D immitis, through postinoculation (PI) week 20. Group-B dogs received a daily regimen of 6.6 mg of DEC/kg of body weight. Group-C dogs received 4.95 mg of oxibendazole/kg daily. Group-D dogs received DEC and oxibendazole, equivalent to the daily doses given to dogs of groups B and C. All dogs given oxibendazole had no A caninum at necropsy. Of the groups receiving DEC, 3 group-B dogs each had 1 to 2 D immitis at necropsy. When results of chronologic IgE determination for all groups were statistically compared, only groups B and C had significant (P = 0.0148 and P << 0.00005, respectively) increases in IgE values. Group-C dogs had the highest IgE values from PI week 10 until the end of the study, whereas IgG values were statistically identical to those of group-A dogs. Group-B dogs given only DEC and having the least number of D immitis of all groups, had IgE values that peaked at PI week 6; values were significantly (P = 0.0002) higher than those for all other groups. In Group-B dogs, IgG values increased significantly (P << 0.00005) only at PI week 20 and were significantly (P << 0.00005) decreased after PI week 6, compared with values for all other groups. Group D containing 6 dogs infected with 1 to 18 D immitis found at necropsy had IgE values betwee.

Prothrombotic changes occurring in the prodromal stages of carbohydrate-induced laminitis were investigated. Hemostatic alterations were evaluated by determining platelet counts, platelet survival, activated partial thromboplastin time, one-stage prothrombin time, and monocyte procoagulant activity. Thrombosis of vessels in the hoof wall was evaluated by contrast arteriography and histologic examination. Of 5 horses, 4 became lame between 28 and 52 hours after carbohydrate administration. Mean platelet count in laminitis-affected horses was lower throughout the prodromal stages of laminitis, compared with that in control horses, but differences were not statistically significant. However, survival of indium-111-labeled platelets was less than the value in control horses by 6 hours after carbohydrate administration. Arteriography of disarticulated feet revealed marked reduction in blood supply to hooves in laminitis-affected horses. Histologic examination of the laminar dermis disclosed microthrombi in venules of the laminar dermis in 2 of 4 affected horses. Statistically significant changes in prothrombin time were not observed, and changes in activated partial thromboplastin time were slight and occurred only at the onset of lameness. Statistically significant changes in monocyte procoagulant activity were not observed. Plasma endotoxin-like activity was not detected in laminitis-affected horses. These data indicate that platelet survival was decreased within the first 6 hours after induction of carbohydrate-induced laminitis, but systemic activation of the coagulation system was not detected.

Cytologic examination of bronchoalveolar lavage fluid (BALF), including phenotypic analysis of lymphocytes, was performed on 32 Standardbreds with poor race performance and endoscopic examination findings characteristic of inflammatory airway disease (IAD). Nucleated cell counts in BALF from IAD-affected horses were higher than those in control horses; the cytologic profile of BALF in affected horses included mixed inflammation, characterized by mild neutrophilia, lymphocytosis, and monocytosis. Eosinophil and mast cell counts were not higher in the IAD-affected group, compared with those in the control group; however, 4 IAD-affected horses had marked eosinophilia (24.7 +/- 4.8% SEM) in BALF. Phenotypic analysis of lymphocytes in BALF obtained from IAD-affected horses revealed a low proportion of CD4-positive cells and B cells, compared with those in the control group; these findings may have been representative of a greater proportion of non-B, non-T cells (null cells) in horses with IAD. The cytologic profile of BALF obtained from horses with IAD differed from that in horses affected with chronic obstructive pulmonary disease, suggesting that the pathogenesis of inflammation in horses with IAD may differ from that of chronic obstructive pulmonary disease.

The aim of the present study was to establish a reliable procedure with nocodazole treatment for the synchronous cleavage of blastomeres of bovine embryos used as nuclear donors for nuclear transfer. Sixteen-cell stage embryos derived from in vitro-maturation, fertilization and culture were used. In three initial experiments, embryos were incubated in mTCM-199 + FCS with various concentrations (0-20 mu-M) of nocodazole under 5% CO2 in air. The concentrations required to arrest the blastomeres in the mitotic phase were examined. The effects of 10 mu-M nocodazole were also examined by observation of the division rate of blastomeres after the removal of nocodazole. Ninety percent (90%) of the blastomeres were arrested in the mitotic phase when embryos were exposed to 10 and 20 mu-M nocodazole. Exposure to 10 mu-M nocodazole had the highest blastomere-cleavage rate (47%). When the exposure period to 10 mu-M nocodazole was prolonged to 36 hr, the division rate of the blastomeres decreased. Furthermore, the effects of 2 culture conditions (mTCM-199 under 5% CO2 in air vs modified synthetic oviduct fluid medium under 5% CO2, 5% O2 and 90% N2) were compared on the division rate of blastomeres of embryos exposed to 10 mu-M nocodazole for 12 hr. When the embryos were exposed to nocodazole in mSOF, the division rate of blastomeres was improved to about 60%. The blastomeres produced by this treatment condition were used as nuclear donors and the developmental potential of the reconstituted embryos was investigated. The developmental rate to the blastocyst stage was 30.1% (58/193). Five embryos were transferred to 5 recipient cows and 2 of the 5 recipients (40%) became pregnant. Subsequently, one normal calf was born.

Objective--To study whether end products of 2 pathways of anaerobic energy metabolism, lactate and purines, that accumulate in the blood after intense exercise indicate any relation to exercise performance. Design--Venous blood samples were taken within 1 and 15 minutes after a trotting race of 2,100 m. Animals--16 Clinically healthy Standardbred trotters. Procedure--Blood and plasma lactate concentrations were measured by enzymatic analyzer, and purines, uric acid and allantoin, were determined by high-performance liquid chromatography. The concentrations of metabolites were then correlated to racing time and individual performance indexes that are annually calculated from the percentage of winnings, placings, and starts rejected, average earnings per start, and the racing record. Results--Blood lactate concentration immediately and calculated cell lactate concentration immediately and 15 minutes after the race correlated positively (P < 0.05 to P < 0.01 ) with the individual performance indexes. Plasma lactate concentration was not correlated to the individual performance indexes. Uric acid concentration, immediately and 15 minutes after the race, was negatively correlated (P < 0.05) to the individual performance indexes, and a positive relation (P < 0.05) was found between the highest concentration of uric acid and the racing time. Concentration of allantoin immediately or 15 minutes after the race did not have any significant correlation to the individual performance indexes. Conclusions--Accumulation of lactate in the blood, which was greater in the superior performing horses, may prove to be an useful predictor of anaerobic capacity. The results also indicate that the loss of purine nucleotides was less in the superior performing horses, although further studies are needed to confirm this.

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.

Investigation of the structure of equine articular cartilage link protein (LP) from individuals ranging in age from 1 to 15 years identified 3 distinct isoforms having molecular weights of 46,000, 43,000, and 41,000. The relative amounts of each of the 3 isoforms altered with age. The largest form did not change with age; however, amounts of the Mr 43,000 and 41,000 forms increased with increasing age. The results suggested that an accumulation, in the extracellular matrix of cartilage, of these 2 smaller products may have arisen from proteolytic cleavage. The complete amino acid sequence of the protein core was determined from complementary DNA products prepared by polymerase chain reaction amplification of cartilage LP mRNA. The sequence had 96% similarity with human LP and with that of other species for which the primary structure has been determined. This high degree of sequence conservation and the isoform data indicate that extracellular processing of LP occurs by similar mechanisms in various species. At the transcription level, equine chondrocytes were found to express LP as 2 abundant mRNA of 5.0 and 3.0 kb, and a smaller mRNA of 1.5 kb. Processing of the LP mRNA in horses, thus, appears to be similar to that found in other species investigated, and although multiple transcripts are present, the coding region remains unaltered and only 1 protein product is made.

The effect that topical administration of cyclosporine would have on the number and type of microorganisms isolated from the corneal surface of dogs with keratoconjunctivitis sicca was studied. Schirmer tear tests were performed on and corneal swab specimens were collected from 61 eyes of 31 dogs with keratoconjunctivitis sicca prior to and after 3, 6, and 12 months of treatment with cyclosporine. In eyes that responded to cyclosporine treatment (Schirmer tear test value increased by greater than or equal to 5 mm/min, compared with pretreatment value), the percentage of eyes from which bacteria were isolated after 3, 6, and 12 months of treatment was significantly (P < 0.001) less than the percentage from which bacteria were isolated prior to treatment. However, among eyes that did not respond to treatment, we did not detect a significant change over time in prevalence of bacteria or type of bacteria isolated. The percentage of eyes from which fungi were isolated decreased during treatment; however, the small number of eyes in which fungal culture results were initially positive precluded demonstration of a significant change. For all eyes, we did not detect any significant differences over time in the frequency with which specific bacterial genera were isolated, with the exception of beta-hemolytic Streptococcus spp. Opportunistic corneal infections were not detected even though none of the dogs received antibiotics. An increase in production of tears, which contain anti-infection proteins, was believed to be the primary factor responsible for the decrease in the percentage of eyes from which microorganisms could be isolated.

We studied the uptake and sequential transneuronal passage of pseudorabies virus (PRV) in rat CNS by use of a combination of immunohistochemistry and in situ hybridization. Protocols for rapid detection of PRV by immunohistochemistry and in situ hybridization in rats with PRV infection of the CNS after intranasal instillation of a wild-type strain of PRV were optimized in vitro, using porcine kidney-15 cells. Pseudorabies virus-specific hybridization signals appeared in the cytoplasm and nucleus of PRV-infected porcine kidney-15 cells by postinoculation (PI) hour 6. In tissue sections of PRV-infected rats, PRV nucleic acids were detected in areas of the rat brain in close proximity to the areas in which PRV antigens were evident. The PRV was initially found in the nucleus of trigeminal ganglion neurons at PI hour 24. At PI hour 72, PRV antigens were observed in the mid-brain, and 24 hours later, in the telencephalon. We also found evidence of specific progressive transsynaptic transmission of the virus, and, on the basis of that, we have constructed a map of the synaptic contacts and pathways in the brain. Therefore, combined use of immunohistochemistry and in situ hybridization was useful for characterizing the pathogenesis of PRV in the CNS of rats after intranasal inoculation, following a pattern that mimics PRV infection of the natural host.

Two indirect ELISA containing outer membrane protein (OMP) and lipopolysaccharide (LPS) antigens from a field isolate of Salmonella choleraesuis var kunzendorf were developed and evaluated in experimentally infected and uninfected control pigs. Experimentally induced infection with S choleraesuis was successfully established in 10 pigs by oral inoculation with 10(8) organisms, and 3 pigs died of clinical salmonellosis at postinoculation (PI) weeks 1, 2, and 4. Swab specimens from tonsils, nostrils, and rectum of pigs were obtained for culture, and sera were evaluated at weekly intervals for 9 weeks after inoculation. The ELISA containing OMP and LPS antigens with either anti-swine IgG or protein albumin-to-globulin ratio (antiglobulin) conjugates were standardized for serologic evaluation. All 4 ELISA (2 OMP and 2 LPS) detected seroconversion by PI week 3 and had sensitivities and specificities of 97.8 and 88.8, 100 and 100, 95.6 and 88.8, and 93.3 and 72.5%, at their ideal cutoff points (negative mean optical density + 2 SD). There was excellent agreement between all 4 ELISA systems as determined by kappa values. Cultures of fecal, tonsil, and nasal swab specimens were positive for S choleraesuis until the fourth week of infection. Fecal swab specimens from 1 pig were positive for S choleraesuis until PI week 7. Persistent infection after antemortem culture results were negative was detected by all 4 ELISA, which indicated consistently high titers until the end of PI week 9. Conventional bacteriologic examination of intestines, mesenteric lymph nodes, bone marrow, lung, liver, spleen, and bile yielded positive results for S choleraesuis in the 3 pigs that died of clinical infection, whereas results were negative in the other 7 pigs infected by the end of PI week 9. Histologic examination of lung, liver, spleen, intestines, and mesenteric lymph nodes from the 3 pigs that died of S choleraesuis infection revealed severe ulceration and inflammatory cell infiltration.