bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cellular defense of the avian respiratory system: Effects of Pasteurella multocida on respiratory burst activity of avian respiratory tract phagocytes
Authors: Ochs Duane L. , Toth Thomas E. , Pyle Robert H. , Siegel Paul B. 
Published: February 2025

SUMMARY
The respiratory tract of healthy chickens contain few free-residing phagocytic cells. Intratracheal inoculation with Pasteurella multocida stimulated a significant (P < 0.05) migration of cells to the lungs and air sacs of White Rock chickens within 2 hours after inoculation. We found the maximal number of avian respiratory tract phagocytes (22.9 ± 14.0 × 106) at 8 hours after inoculation. Flow cytometric analysis of these cells revealed 2 populations on the basis of cell-size and cellular granularity. One of these was similar in size and granularity to those of blood heterophils. Only this population was capable of generating oxidative metabolites in response to phorbol myristate acetate. The ability of the heterophils to produce hydrogen peroxide, measured as the oxidation of in-tracellularly loaded 2′,7′-dichlorofluorescein, decreased with time after inoculation. These results suggest that the migration of heterophils, which are capable of high levels of oxidative metabolism, to the lungs and air sacs may be an important defense mechanism of poultry against bacterial infections of the respiratory tract.
Pathologic, hematologic, and serologic changes in rabbits given T-2 mycotoxin orally and exposed to aerosols of Aspergillus fumigatus conidia
Authors: Niyo K. A. , Richard J. L. , Niyo Y. , Tiffany L. H. 
Published: February 2025

SUMMARY
The influence of immunosuppression by T-2 mycotoxin on the fungal disease aspergillosis was investigated in rabbits. Four groups of rabbits (groups 1A, 1B, 3A, and 3B) were given 0.5 mg of T-2 toxin/kg of body weight/day, po; in addition, rabbits of groups 3A and 3B were exposed to aerosols of Aspergillus fumigatus conidia from days 7 through 16. Rabbits of groups 2A and 2B were exposed to A fumigatus aerosols, but were not given T-2 toxin, and rabbits of group 0 served as controls. Two rabbits of group 1A, 1 rabbit of group 1B, and 1 rabbit of group 3A died before scheduled necropsy. Rabbits of groups 1A, 2A, and 3A were killed and necropsied on day 17, and the remaining rabbits (groups 0, 1B, 2B, and 3B) were killed and necropsied on day 28. Changes caused by T-2 toxin included leukopenia, marginal anemia, and increased number of and morphologic changes in nucleated erythrocytes by day 21, followed by a regenerative hematologic response. Serum alkaline phosphatase and sorbitol dehydrogenase activities and antibody response to A fumigatus (as measured by an indirect hemagglutination test) were decreased by T-2 toxin ingestion. Rabbits with aspergillosis had leukocytosis, increased pcv, and increased antibody response to A fumigatus. Histologic lesions consisting of centrilobular hepatocellular swelling, portal and periportal fibrosis, and lymphocyte necrosis and/or depletion within secondary lymphoid tissue were observed in most rabbits treated with T-2 toxin. Normal defense mechanisms against A fumigatus infection were compromised by T-2 treatment, as evidenced by the severity and extent of lung lesions, greater number of hyphal elements observed, and greater number of colonies of A fumigatus isolated from rabbits of groups 3A and 3B. There were no significant changes in group-0 rabbits.
Clinical evaluation of transmissible gastroenteritis virus vaccines and vaccination procedures for inducing lactogenic immunity in sows
Authors: Moxley Rodney A. , Olson LeRoy D. 
Published: February 2025

SUMMARY
Two federally licensed attenuated live transmissible gastroenteritis (TGE) virus vaccines (an IM vaccine and an oral-IM vaccine) and 1 nonlicensed nonattenuated live TGE virus vaccine were evaluated and compared in sows free of TGE virus-neutralizing antibodies. Litters from the sows were challenge exposed at 3 and 5 days of age, and results were combined according to the vaccine administered to the sows. The survivability of pigs suckling sows vaccinated with the nonattenuated vaccine was significantly (P < 0.01) greater than that of pigs suckling sows vaccinated with the IM attenuated vaccine, significantly (P<0.05) greater than that of pigs suckling sows vaccinated with the oral-IM attenuated vaccine, and significantly (P < 0.05) greater than that of pigs suckling sows that had not been vaccinated. The differences, however, between survivability of litters from sows vaccinated with the IM attenuated vaccine or the oral-IM attenuated vaccine and that of litters from the sows not vaccinated were not significant (P> 0.10). The nonattenuated TGE vaccine, although giving a higher level of protection than the attenuated vaccine, was eventually overwhelmed. Dexamethasone did not increase the incidence of diarrhea, and levamisole did not potentiate the lactogenic immunity in sows after given their first dose of the nonattenuated vaccine. Survivability in litters suckling sows that developed diarrhea after given their first dose of the nonattenuated vaccine was not greater than that in litters suckling sows that did not develop diarrhea. The best results were obtained when 3-day-old suckling pigs were challenge exposed with virulent TGE virus.
Effect of vaccination with a pentavalent leptospiral vaccine on Leptospira interrogans serovar hardjo type hardjo-bovis infection of pregnant cattle
Authors: Bolin Carole A. , Thiermann Alejandro B. , Handsaker Annette L. , Foley John W. 
Published: February 2025

SUMMARY
Effectiveness of a pentavalent leptospiral vaccine to protect cattle from infection and reproductive problems caused by Leptospira interrogans serovar hardjo type hardjo-bovis was evaluated. Seven cows were vaccinated once and 8 cows were vaccinated twice with a USDA-licensed pentavalent leptospiral vaccine. Five cows were maintained as nonvaccinated controls. Cows were bred 1 to 2 months after the last vaccination. During the 4th to 6th month of gestation, all cows were challenge exposed on 4 occasions by conjunctival instillation of 108 serovar hardjo type hardjo-bovis organisms and on 3 occasions by conjunctival instillation of urine from a cow shedding hardjo-bovis. All control cows and 13 of 15 vaccinated cow became infected and shed leptospires in the urine. Leptospires were detected in fewer urine samples collected from vaccinated cows, compared with those collected from control cows. Four stillborn calves and 3 weak calves were born to control and vaccinated cows. Leptospires were detected in the kidneys of 11 apparently healthy calves born to vaccinated and control cows. Agglutinating antibodies were not detected inthe precolostral glutinating tral serum of these calves.
Comparative effects of cholera toxin, Salmonella typhimurium culture lysate, and viable Salmonella typhimurium in isolated colon segments in ponies
Authors: Murray Michael J. , Doran Richard E. , Pfeiffer Carl J. , Tyler David E. , Moore James N. , Sriranganathan Nammalwar 
Published: February 2025

SUMMARY
Isolated segments of left dorsal colon and a side-to-side colocolostomy (between the left ventral colon and left dorsal colon) were surgically created in 6 adult ponies. Four segments, each separated by an empty segment, were inoculated (20 ml) with 1 of the following 4 solutions : phosphate buffered saline solution (PBSS)/1% polyethylene glycol (PEG); purified cholera toxin in PBSS/1% PEG (5 μg cholera toxin/ml of PBSS/1% PEG); lyophilized Salmonella typhimurium UCD 1755 culture lysate, reconstituted in PBSS/1% PEG; and viable S typhimurium UCD 1755 (108 organisms/ml of PBSS /1% PEG). Twenty hours following inoculation of the treatment solutions into the isolated colon segments, the ponies were reanesthetized. Fluid accumulation in the isolated segments was measured, and tissue samples from isolated segments were taken for examination by light microscopy and electron microscopy, and for measurement of mucosal cyclic adenosine monophosphate levels.
There was fluid accumulation in segments inoculated with cholera toxin in 4 ponies (29.5 ± 12.7 ml), and in segments inoculated with S typhimurium UCD 1755 culture lysate in 3 ponies (14.0 ± 8.7 ml). There was no fluid accumulation in segments inoculated with either the control solution (PBSS /1% PEG) or viable S typhimurium UCD 1755. There was significantly (P < 0.05) less cyclic adenosine monophosphate in segments inoculated with cholera toxin, Salmonella lysate, and viable Salmonella, compared with control segments. Histologically, there were minimal changes in control segments, consisting of mild to moderate submucosal edema and capillary congestion. Changes in the other segments were more pronounced and included neutrophilic infiltration and exocytosis, with the changes increasing in severity in the segments inoculated with cholera toxin, S typhimurium culture lysate UCD 1755, and viable S typhimurium UCD 1755, respectively. Ultrastructurally, mucosa from control segments was normal. Mucosa from segments inoculated with cholera toxin had swollen endoplasmic reticula and basolateral separation of surface epithelial cells. Mucosa from segments inoculated with S typhimurium UCD 1755 culswollen smooth and rough endoplasmic reticula, separature lysate and viable S typhimurium UCD 1755 had tion of epithelial cells, degeneration of microvilli, and goblet cell degeneration.
Evaluation of the specificity of Pasteurella multocida somatic antigen-typing antisera prepared in chickens, using ribosome-lipopolysaccharide complexes as inocula
Authors: Rimler R. B. , Angus R. D. , Phillips M. 
Published: February 2025

SUMMARY
Purified lipopolysaccharides (LPS) from 16 serotypes of Pasteurella multocida were complexed with Aspergillus fumigatus ribosomes. The complexes were used as inocula to prepare antisera, in chickens, for somatic antigen typing by the gel diffusion precipitin test (GDPT). Antisera made against 15 of 16 LPS reacted with their respective specific heat-stable antigens in the GDPT and homologous LPS in the passive hemagglutination test. Antisera could not be made against serotype 15 LPS. Correlation was not observed between intensity of the precipitin reaction in the GDPT and titer to homologous LPS in the passive hemagglutination test. Most antisera cross-reacted with other heat-stable antigens of other serotypes in the GDPT. Many of these cross-reactions were eliminated by dilution. Crossreactions that occurred in the GDPT with antisera made against LPS of serotypes 2,5,7, and 8 could not be eliminated by dilution.
Effects of distention and neostigmine on jejunal vascular resistance, oxygen uptake, and intraluminal pressure changes in ponies
Authors: Parks H. , Stick J. A. , Arden W. A. , Chou C. C. , Hengemuhle S. M. 
Published: February 2025

SUMMARY
The influence of distention (high baseline intraluminal pressure) and neostigmine methylsulfate on intestinal vascular resistance, oxygen uptake, and intraluminal pressure changes (rhythmic contractions) was studied in terminal jejunal segments, which were perfused at a constant rate, in 16 anesthetized ponies. When baseline intraluminal pressure was increased to 10 mm of Hg, the intestinal vascular resistance and amplitude of rhythmic contractions were increased. Neostigmine induced cyclic increases in amplitude of rhythmic contractions whether intraluminal pressure was 0 or 10 mm of Hg. Neostigmine also increased intestinal oxygen uptake at intraluminal pressures of 0 mm of Hg, but not at 10 mm of Hg, and vascular resistance was not altered at either intraluminal pressure. The results indicate that intestinal hemodynamics are adversely affected by distention. Further, neostigmine did not adversely affect intestinal hemodynamics while increasing rhythmic contractions, suggesting that neostigmine may be useful in the treatment of ileus in equids.
Pulsed-wave Doppler evaluation of intracardiac blood flow in 30 clinically normal Standardbred horses
Authors: Reef Virginia B. , Lalezari Khosrow , De Boo Job , van der Belt Anton Jan , Spencer Pamela A. , Dik Kees J. 
Published: February 2025

SUMMARY
Pulsed-wave Doppler echocardiography was performed on 30 clinically normal 1-to 6-year-old racing Standardbreds. There were 13 females, 13 geldings, and 4 stallions. Cardiac disease was not detected with M-mode, 2-dimensional real-time or pulsed-wave Doppler echocardiography.
Normal flow velocities for right and left atrial outflow, right and left ventricular outflow, the aorta, and pulmonary artery were determined. Peak flow velocities for right and left atrial outflow occurred during the rapid filling phase and were higher toward the mitral valve (mean, 0.70 ± 0.24 m/s) than toward the tricuspid valve (mean, 0.49 ± 0.17 m/s). Peak flow velocities in the right and left ventricular outflow tracts were similar (means, 0.81 ± 0.10 m/s and 0.75 ± 0.39 m/s, respectively). Peak flow velocities in the pulmonary artery (mean, 1.09 ± 0.42 m/s) and aorta (mean, 1.01 ± 0.29 m/s) were similar, although flow peaked earlier in systole in the aorta than in the pulmonary artery.
Clinical studies of fish blood: Importance of sample collection and measurement techniques
Authors: Heming Thomas A. 
Published: February 2025

SUMMARY
Effects of blood sample collection and measurement techniques were assessed for blood gas tensions, acid-base status, and hematologic and plasma biochemical values of rainbow trout. Blood samples were collected via intraaortic cannulae from immersed, unrestrained fish and from emersed, restrained fish. The samples were analyzed at either fish body temperature (10 to 14 C) or clinical blood analyzer temperature (37 C); results obtained at 37 C were back-adjusted to fish body temperature, using standard mammalian temperature-correction factors. Fish emersion and handling for 30 seconds significantly (P < 0.05) altered blood Pco2, acid-base status, and hematologic and plasma biochemical values. The results were consistent with respiratory acidosis and hemoconcentration. The use of mammalian temperature-correction factors for determination of fish blood gas tensions and acid-base status yielded values that were significantly (P < 0.05) different from those measured directly at fish body temperature.
Etiologic agents, incidence, and improved diagnostic methods of cantharidin toxicosis in horses
Authors: Ray Allen C. , Kyle Ana Laura G. , Murphy Michael J. , Reagor John C. 
Published: February 2025

SUMMARY
In addition to the 3-striped blister beetles (Epicauta equexa and E occidentalis), other sources of equine cantharidin toxicosis were identified at the Texas Veterinary Medical Diagnostic Laboratory and included E albida and E attrivittata and the previously incriminated E pardalis and E pennsylvanica. Improved methods for diagnosing cantharidin or blister beetle toxicosis involve partial purification of urine and gastric content extracts, using silica cartridges, followed by analysis, using capillary gas chromatography/mass spectrometry. During a 26-month period, 53 episodes of cantharidin toxicosis in horses were confirmed at our diagnostic laboratory. Concentrations of cantharidin in urine and gastric contents ranged from 0.0003 to 3.50 μg/g. Peak incidences were observed in late summer and early fall.
Duration of strain 2308 infection and immunogenicity of Brucella abortus lipopolysaccharide in five strains of mice
Authors: Phillips Marshall , Pugh George W. , Deyoe Billy L. 
Published: February 2025

SUMMARY
A study was conducted to compare immunogenicity of a Brucella abortus lipopolysaccharide (lps) and the duration of infection in 5 strains of mice. Mice of strains CBA/NJ, BALB/c, CD-1, C3H/HeN, and C3H/HeJ were allotted into 2 large groups (vaccinated with proteinase K-treated lps or nonvaccinated) and 6 subgroups based on the intervals between challenge exposure to B abortus strain 2308 and the week the response data were obtained. Criteria used in comparing responses between the various strains of mice as well as between vaccinated and nonvaccinated mice were splenomegaly, colony-forming units (cfu) from spleens, and antibody titers. Responses were evaluated at 1, 2, 3, 5, 8, and 12 weeks after challenge exposure.
Results indicated that all strains of mice became infected and maintained infection throughout the 12-week period, the percentages of mice infected were significantly (P < 0.05) less in vaccinated mice for the first 5 weeks after challenge exposure, and there were no direct correlations between increased immunoglobulins (IgM and IgG titers) and reduction in cfu. Vaccinated mice of strains BALB/c, CD-1, C3H/HeN, and C3H/HeJ had increased titers when challenge exposed and also had significantly (P < 0.05) smaller spleens and lower cfu. Vaccinated CBA/NJ mice did not have marked antibody titers.
The overall results indicated that vaccination with lps offers some initial protection against B abortus strain 2308 infection, but this protection disappears gradually and in various degrees in the 5 strains of mice studied.
Functional and metabolic activity of bovine pulmonary lavage cells phagocytically stimulated with pathogenic isolates of Pasteurella haemolytica
Authors: Richards Alan B. , Renshaw Harland W. 
Published: February 2025

SUMMARY
Live Pasteurella haemolytica biotype A, serotype 1 isolates (n = 3) and Escherichia coli K-12, strain W3110, were reacted with bovine pulmonary lavage cell (plc) suspensions. The comparative effects of the different bacteria on the functional and metabolic activity of alveolar macrophages (amo) in the plc suspensions were assessed simultaneously by use of 51Cr release, luminol-dependent chemiluminescence (ldcl), and amo bactericidal assays. The bovine plc responded differently to E coli, than to the 3 P haemolytica isolates in each of the 3 experimental test systems; however, responses to each of the P haemolytica isolates were not found to be significantly different.
Unopsonized live P haemolytica cells adversely affected the functional and metabolic response of plc, whereas there was no evidence of a cytotoxic (cytocidal) influence of E coli. A difference in 51Cr release for reaction mixtures containing E coli and P haemolytica was not detected at zero time; however, at each subsequent time, reaction mixtures phagocytically stimulated with P haemolytica had significantly increased amount of 51Cr release (P < 0.05), compared with those mixtures containing E coli. Bovine amo in the plc suspensions were able to effectively kill E coli in vitro, but were unable to prevent survival and subsequent growth of P haemolytica. The luminol-dependent chemiluminescence profiles for reaction mixtures phagocytically stimulated with E coli provided evidence of sustained production of oxygen radicals with antimicrobial capabilities by bovine amo in the plc. Production of these highly reactive antimicrobial oxidants appeared initially in cultures containing P haemolytica but, subsequently, their production declined precipitously and ceased altogether.
Suppression of preovulatory luteinizing hormone surges in heifers after intrauterine infusions of Escherichia coli endotoxin
Authors: Peter A. T. , Bosu W. T. K. , DeDecker R. J. 
Published: February 2025

SUMMARY
A study was conducted to test the hypothesis that high cortisol concentrations associated with products of infections (endotoxin) cause derangement in the neuroendocrine mechanism controlling ovulation in heifers. Eight Holstein heifers were given 2 injections of prostaglandin (pg), 11 days apart, to synchronize estrus. Starting from 25 hours after the second injection of pg (pg-2), the uterus of each heifer was infused with 5 ml of pyrogen-free water (control, n = 3) or Escherichia coli endotoxin (5 μg/kg of body weight) in 5 ml of pyrogen-free water (treated, n = 5), once every 6 hours for 10 treatments. Blood samples were obtained every 15 minutes via indwelling jugular catheter for an hour before and 2 hours after each infusion, then hourly until an hour before the next infusion. Ultrasonography of the ovaries was performed every 12 hours, starting 24 hours after pg-2 injection until 96 hours after pg-2 injection. Serum concentrations of luteinizing hormone and cortisol were determined by validated radioimmunoassays. Changes in cortisol concentrations were not detected in control heifers with preovulatory luteinizing hormone surges at 60 to 66 hours after pg-2 injection, followed by ovulations 72 to 96 hours after pg-2 was injected. None of the treated heifers ovulated, and the resulting follicular cysts (14 to 18 mm diameter) persisted for 7 to 21 days. In all treated heifers, serum cortisol concentrations increased (4- to 10-fold) during the first 2 hours after each infusion and then decreased gradually until the next infusion. Luteinizing hormone concentrations remained at baseline values throughout the treatment period in all treated heifers. These findings suggested that endotoxin-induced increases in cortisol concentrations during the preovulatory period of the estrous cycle prevented ovulations by blunting the preovulatory luteinizing hormone surges.
Induction of equine postanesthetic myositis after halothane-induced hypotension
Authors: Lindsay W. A. , Robinson G. M. , Brunson D. B. , Majors L. J. 
Published: February 2025

SUMMARY
Wick catheters were used to measure intracompartmental pressures of the extensor carpi radialis muscles and long heads of the triceps brachii muscles of 7 horses maintained under halothane anesthesia during controlled ventilation. Horses were positioned in left lateral recumbency on a water bed for 4 hours. Using a crossover design, 6 of the 7 horses were subjected to normotensive and hypotensive anesthesia on separate occasions. Hypotension was achieved by increasing the inspired halothane concentration. Hematologic and biochemical measurements were determined at designated intervals before, during, and for 7 days after each anesthetic episode.
Under hypotensive conditions, 2 horses developed severe, generalized myositis and were euthanatized. Three of the 5 other horses developed swelling of the downside masseter muscle, 4 demonstrated mild extensor deficits of the downside forelimb, and 1 had a severe extensor deficit of the uppermost hind limb.
As a group, the hypotensive horses had markedly increased activities of serum enzymes (creatine kinase, aspartate transaminase, and blood lactate) and abnormalities in calcium-phosphorus homeostasis. Lameness or enzyme alterations were not observed in normotensive horses.
Although the intracompartmental pressure values were markedly increased in the muscle bellies of the compressed limbs of all horses, there was a statistically significant difference in intracompartmental pressures between the downside or compressed muscle compartments of the extensor carpi radialis of hypotensive and normotensive horses.
High concentrations of halothane may predispose anesthetized horses to postanesthetic myositis, even when protective padding is used. Intracompartmental muscle pressure, as measured by the wick catheter, may not be a reliable predictor of equine postanesthetic lameness.