bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of dexamethasone on cell-mediated immune responses in cattle sensitized to Mycobacterium bovis
Authors: Doherty Michael L. , Bassett Hugh F. , Quinn Patrick J. , Davis William C. , Monaghan Michael L. 
Published: January 2024

SUMMARY
Systemic administration of dexamethasone led to a significant reduction in the size of the tuberculin reaction in response to intradermal injection of bovine purified protein derivative in 18 cattle experimentally sensitized to Mycobacterium bovis (P < 0.01) and 8 cattle naturally infected with M bovis (P < 0.001). The reaction in 6 of the 7 M bovis-infected cattle that received dexamethasone was classified as negative for the standard interpretation of the single intradermal comparative tuberculin test. Significantly fewer BoCD2+ (P < 0.05) and BoCD4+ T cells (P < 0.001) were present at the reaction site and in blood of dexamethasone-treated cattle, compared with untreated control cattle. Significantly fewer cells expressing the interleukin-2 receptor and WC1+ γδ T cells (P < 0.001), and a significantly greater number of cells expressing the ACT2 antigen (P < 0.05) were found at the reaction site in dexamethasone-treated cattle than in controls. The number of BoCD8+ T cells at the reaction site and in blood was not significantly affected by administration of dexamethasone. In vitro production of interferon-γ by lymphocytes incubated with bovine purified protein derivative also was significantly lower (P < 0.01) in the dexamethasone-treated cattle.
Evaluation of fetal infection and abortion in pregnant ponies experimentally infected with Ehrlichia risticii
Authors: Long Maureen T. , Goetz Thomas E. , Kakoma Ibulaimu , Whiteley Herbert E. , Lock Theodore E. , Holland Cynthia J. , Foreman Jonathan H. , Baker Gordon J. 
Published: January 2024

SUMMARY
Fetal infectivity of Ehrlichia risticii was investigated in 19 ponies that were E risticii negative on the basis of results of an indirect fluorescent antibody (ifa) test. Thirteen pregnant ponies were infected by iv administration of E risticii between 90 and 180 days of gestation. Six pregnant ponies served as noninfected controls. Each infected pony had clinical signs of equine monocytic ehrlichiosis, was confirmed to be ehrlichemic, and developed an ifa titer to E risticii. Two infected ponies became recumbent, were unresponsive to supportive care, and were euthanatized. After recovery from clinical illness, the remaining ponies were observed throughout gestation for reproductive abnormalities. On abortion, each fetus was necropsied and tissue specimens from the liver, bone marrow, spleen, colon, and mesenteric lymph nodes were inoculated into canine monocyte cell cultures. Six infected ponies aborted at a mean 217 days of gestation, which was between postinoculation days 65 and 111. Five fetuses were recovered for evaluation, and E risticii was isolated from 4 of them. All 5 fetuses recovered had similar histologic findings, including enterocolitis, periportal hepatitis, and lymphoid hyperplasia with necrosis of the mesenteric lymph nodes and spleen. All 5 fetuses tested negative for IgG to E risticii, although 3 had low IgM titer to E risticii. The remaining 5 infected ponies had normal parturition. Presuckle ifa titer to E risticii was measured in 4 of the term foals, and results for 3 were positive. Two foals from infected ponies were monitored for 6 months and daily gain in body weight was comparable to that of a control foal. None of the control ponies became ill or seroconverted during the clinical illness phase, and none aborted throughout gestation. Two control ponies seroconverted to E risticii 6 weeks before parturition. Results of this study indicate that E risticii is a primary abortifacient under experimental conditions.
Comparison of maternal blood and fetal liver selenium concentrations in cattle in California
Authors: Kirk John H. , Terra Ronald L. , Gardner Ian A. , Wright Jim C. , Case James T. , Maas John 
Published: January 2024

SUMMARY
Selenium concentration was measured in paired maternal blood samples and fetal liver specimens collected at a San Joaquin County, Calif, slaughterhouse (beef = 19, dairy = 54) and from bovine aborted fetuses submitted to the California Veterinary Diagnostic Laboratory System (CVDLS; beef = 20, dairy = 20). Of the slaughterhouse samples and specimens, dairy maternal blood selenium concentration was significantly (P < 0.001) higher (mean ± sd; 0.22 ± 0.056 µg/ml) than that for beef breeds (0.137 ± 0.082 µg/ml). The CVDLS mean maternal blood selenium concentration for the dairy-breed samples (0.192 ± 0.028 µg/ml) was similar to that for the slaughterhouse dairy-breed samples, but was greater than that for the slaughterhouse beef-breed samples. Slaughterhouse mean fetal liver selenium content also was higher (P < 0.001) for the dairy breeds (0.777 ± 0.408 µg/g), compared with the beef breeds (0.443 ± 0.038 µg/g). Mean fetal liver selenium content for slaughterhouse specimens was higher (P < 0.002) than that for the CVDLS specimens (beef, 0.244 ± 0.149 µg/g; dairy, 0.390 ± 0.165 µg/g). At the CVDLS, dairy fetal liver content was greater (P < 0.001) than that for beef breeds. Mean ratio of fetal liver selenium content to maternal blood selenium concentration was 3.53 ± 1.89 for dairy breeds at the slaughterhouse (liver-to-blood correlation [r] = 0.38), and was 2.11 ± 1.00 for dairy breeds at the CVDLS (r = 0.31) and 3.43 ± 1.50 for beef breeds (r = 0.58). Both slaughterhouse breed ratios were significantly (P < 0.002) greater than the CVDLS dairy-breed ratio. On the basis of these results, breed and source location should be taken into account when interpreting selenium values. Fetal liver selenium content should only be used as a screening test and combined with whole blood selenium concentration from clinically normal herdmates to evaluate herd selenium status.
Effect of hypertonic saline solution on left ventricular afterload in normovolumic dogs
Authors: Constable Peter D. , Muir William W. , Binkley Phillip F. 
Published: January 2024

SUMMARY
The effects of hypertonic saline solution (hss) and hyperosmotic dextrose (hd; 2,400 mosm/L, 4 mV kg of body weight) on left ventricular afterload were determined in normovolumic, chloralose-anesthetized, autonomically blocked dogs (n = 8). Solutions were infused iv over 3 minutes. Left ventricular afterload was assessed by use of a dual-tipped micromanometer catheter with an electromagnetic fluidvelocity sensor located in the ascending aorta, and the impedance spectrum was calculated after Fourier analysis of signal-averaged aortic pressure and flow signals. Hypertonic saline solution and hd decreased peripheral resistance, reflection coefficient at zero frequency, and frequency of the first zero crossing of the phase angle for 3 to 5 minutes after either fluid was administered. Characteristic impedance was not altered by hss or hd. These impedance spectrum changes indicate transient vasodilatation and afterload reduction. We conclude that the vascular effect of an ionic hyperosmotic solution (hss) is similar to that of a nonionic hyperosmotic solution (hd), and that hss and hd transiently decrease afterload in normovolumic dogs. The duration of the afterload reduction after hss administration appeared to be too short to be of great clinical benefit.
Site-specific proteoglycan characteristics of third carpal articular cartilage in exercised and nonexercised horses
Authors: Palmer Jan L. , Bertone Alicia L. , Malemud Charles J. , Carter Barry G. , Papay Robert S. , Mansour Joseph 
Published: January 2024

SUMMARY
The relevance of site and the influence of exercise on third carpal articular cartilage proteoglycan (pg) were assessed in 16 horses. Six horses were exercised (exercised group) for 30 minutes, 3 times/wk, for 6 weeks. The other 10 horses (nonexercised group) were housed in box stalls for the same 6-week period. At week 6, articular cartilage from the proximal surface of the right third carpal bone was harvested and cultured with radioactive sulfate to label newly synthesized pg. Endogenous pg was measured by use of a uronic acid assay. Newly synthesized and endogenous pg were characterized by use of Sepharose CL-2B chromatography, composite gel electrophoresis, and/or immunoblot analysis with monoclonal antibody 1C6 directed against the hyaluronic acid-binding region on pg.
There was a significant (P = 0.0002) effect of exercise, but not site, on newly synthesized pg, which was increased in the exercised horses, compared with the nonexercised horses at the end of the 6-week study period. The increase in newly synthesized pg was not reflected in the existing cartilage matrix as there was no significant difference between groups in endogenous pg. However, there was a significant (P = 0.01) effect of site on endogenous pg, with the nest of sites located in the palmar aspect of the radial facet containing a greater concentration of endogenous pg than the nests of sites located on the dorsal aspect of the radial facet or all sites on the intermediate facet. Most newly synthesized pg in both groups consisted of hydrodynamically small pg monomers. However, there was a change in the profile of newly synthesized pg at some sites in the exercised horses to include an early elution peak on Sepharose CL-2B, which may contain aggregating pg. All sites in both groups contained a diverse population of endogenous large and small pg on toluidine blue-stained composite gels that reacted with monoclonal antibody 1C6, indicating the potential to bind to hyaluronic acid.
Serum sensitivity of field isolates and laboratory strains of Brucella abortus
Authors: Eisenschenk F. C. , Houle J. J. , Hoffmann E. M. 
Published: January 2024

Abstract

Objective
To evaluate the ability of bovine complement to kill a variety of field isolates and laboratory strains of Brucella abortus.

Design
The experimental approach was to determine the sensitivity of B abortus isolates to killing by bovine serum, and to document the role of complement in brucellacidal activity.

Sample population
Six laboratory isolates and 12 field isolates of B abortus were tested.

Procedure
The ability of B abortus to survive exposure to undiluted bovine serum for 2 hours at 37 C was assessed. The role of complement in killing was determined by examining the ability of heat (56 C for 60 minutes) and cobra venom factor to obliterate the activity in serum, and by detecting binding of the ninth component of bovine complement to serum-sensitive target cells.

Results
Isolates of B abortus that were resistant to the bactericidal activity of normal bovine serum were revealed. These included field isolates and laboratory strains. Furthermore, the study confirmed earlier reports that bovine serum-mediated killing of B abortus is caused by the complement cascade.

Conclusions
Some isolates of B abortus, like other gram-negative bacteria, were resistant to complement-mediated killing. Resistance was associated with smooth colony morphology. Isolates lacking detectable O antigen were serum sensitive.
Comparative cardiopulmonary effects of intramuscularly administered etorphine and carfentanil in goats
Authors: Heard Darryl J. , Nichols Wilmer W. , Buss Daryl , Kollias George V. 
Published: January 2024

Abstract

Objective
To determine comparative cardiopulmonary effects of IM administered etorphine and carfentanil in goats.

Animals
Seven clinically normal adult female goats.

Design
Each goat received at least 9 drug treatments (etorphine HCI, 5 (twice], 10, 20, and 40 and carfentanil citrate, 5, 10, 20, and 40 μg/kg of body weight), with a minimal 2-day interval between trials. Although drug dosages were randomized, etorphine and carfentanil treatments were alternated. To assess for drug tolerance, the first and last treatments always were etorphine (5 μg/kg).

Procedure
All goats were instrumented for long-term cardiopulmonary variable data collection.

Results
Both drugs induced rapid catatonic immobilization, characterized by limb and neck hyperextension, with occasional vocalization and bruxation. Etorphine elicited transient violent struggling and vocalization immediately. Time to immobilization appeared dose-dependent, and was more rapid with carfentanil (≤ 5 minutes) than etorphine (5 to 10 minutes) at all dosages. Recovery to standing occurred earlier for etorphine (1 to 2 hours) than carfentanil (> 2 hours) at all dosages.
Both drugs at all dosages significantly (P ≤ 0.05) increased systemic and left ventricular (LV) end-diastolic pressures, LV peak negative dP/dt, total peripheral resistance (TPR), hemoglobin concentration, and left atrial (LA) and pulmonary O2 contents. They also significantly decreased heart and respiration rates, and TPR. A significant increase was observed at some dosages for LV stroke volume and index, LV peak positive dP/dt, mean pulmonary artery pressure, PaO2, pulmonary artery oxygen partial pressure, PaCO2, pulmonary mixed venous carbon dioxide partial pressure, LA hemoglobin saturation, LA transport index, and body temperature. Pulmonary and systemic mixed venous carbon dioxide and oxygen contents were significantly decreased at some dosages.

Conclusions
Intramuscularly administered etorphine and carfentanil induce hypertension, bradycardia, and bradypnea in goats. The hypertension appears attributable to an increase in TPR.

Clinical Relevance
Although the cardiopulmonary effects of carfentanil occurred more rapidly, these effects were similar in magnitude for etorphine and carfentanil over the evaluated dosage range. (Am J Vet Res 1996;57:87-96)
Detection of foot-and-mouth disease viral sequences in various fluids and tissues during persistence of the virus in cattle
Authors: Bergmann Ingrid E. , Malirat Viviana , Augé de Mello Paulo , Gomes Ivo 
Published: January 2024

Abstract

Objective
To assess whether foot-and-mouth disease virus (FMDV)-specific sequences could be identified in tissues from persistently virus-infected animals.

Design
Cattle with experimentally induced persistent FMDV infections were slaughtered at 750 days after viral exposure. Experimentally infected pigs were slaughtered at 28 days after FMDV inoculation. Postmortem specimens were asceptically removed.

Animals
Three bovids and 3 pigs were studied, as well as 1 control animal for each species.

Procedure
Various tissues were examined for the presence of FMDV-specific sequences by dot-blot hybridization assay, using a molecularly cloned FMDV cDNA corresponding to the polymerase coding region.

Results
The FMDV-specific genomic sequences were only detected in RNA from spleen, lung, larynx, tonsils, pancreas, liver, esophagus, and WBC of bovids.

Conclusions
It was established that, at late stages of the persistent infection, when virus isolation was not possible, cattle may carry FMDV-specific sequences in different tissues. Retention of viral sequences could not be demonstrated in specimens from experimentally infected swine, 28 days after viral inoculation.
Helicobacter mustelae-associated hypergastrinemia in ferrets (Mustela putorius furo)
Authors: Perkins Scott E. , Fox James G. , Walsh John H. 
Published: January 2024

Abstract

Objective
To determine whether ferrets naturally infected with Helicobacter mustelae were hypergastrinemic, compared with ferrets that were specific-pathogen-free (SPF) for H mustelae.

Design
Plasma gastrin concentrations in H mustelae-infected and SPF ferrets were measured at 3 time points and compared to determine whether H mustelae was associated with hypergastrinemia.

Animals
21 H mustelae-infected ferrets and 10 SPF ferrets.

Procedure
The H mustelae status of the ferrets was confirmed prior to commencement of the study. Gastric endoscopy was used to obtain gastric mucosal pinch biopsy specimens that were processed for rapid-urease assay, microaerophilic culturing, and histologic evaluation. Plasma gastrin concentrations were determined at 3 time points: baseline after a 12-hour nonfeeding period, and 30 and 60 minutes after oral administration of a standardized meal. Gastrin was measured by radioimmunoassay.

Results
The results for the H mustelae-infected group (mean ± SEM pg/ml) were: baseline, 54.4 ± 2.56; 30 minutes, 94.5 ± 6.05; and 60 minutes, 82.6 ± 5.73. The SPF group results were: baseline, 55.8 ± 7.35; 30 minutes, 80.8 ± 5.77; and 60 minutes, 59.7 ± 4.95. There was a significant (P < 0.01) difference at the 60-minute time point between the 2 groups of animals. The H mustelae group had a 17% higher mean gastrin value at 30 minutes.

Conclusions
Helicobacter mustelae is associated with hypergastrinemia in ferrets.

Clinical Relevance
Helicobacter-induced hypergastrinemia may be related to the pathogenesis of peptic ulcer disease in ferrets.
Role of prostaglandins and enteric nerves in Escherichia coli heat-stable enterotoxin (STa)-induced intestinal secretion in pigs
Authors: Hayden Ursula L. , Greenberg Richard N. , Carey Hannah V. 
Published: January 2024

Abstract

Objective
To examine the role of prostaglandins and enteric nerves in mediating intestinal secretion induced by enterotoxigenic Escherichia coli heat-stable enterotoxin (STa) in pig jejunum and distal portion of the colon.

Animals
Two- to 3-week-old suckling crossbred pigs were studied.

Design
Changes in ion transport in response to mucosal addition of E coli STa to jejunal and colonic tissues were studied in the presence and absence of inhibitors.

Procedure
Flat sheets of muscle-stripped proximal portions of the jejunum and distal portions of the colon were mounted in Ussing chambers equipped to measure changes in short-circuit current (Isc), a measure of active ion transport. Tissues were exposed to 200 ng of STa/ml administered to mucosal solutions, and subsequent changes in Isc were recorded.

Results
In control tissues, changes in Isc induced by STa in the distal colon were significantly greater (21.4 ± 4 µA/cm2) than those observed in the jejunum (14.0 ± 2 µA/cm2). When either segment was exposed to the neurotoxin, tetrodotoxin, or to the nitric oxide synthase inhibitor, NG-nitro-L-arginine-methyl ester, Isc responses to STa were unchanged, suggesting no involvement of submucosal nerves in mediating STa-induced secretion. When tissues from the distal portion of the colon and jejunum were pretreated with piroxicam, a prostaglandin synthesis inhibitor, the STa-induced Isc response was significantly reduced by 52 and 57%, respectively.

Conclusions
These results indicate that the pig jejunum and distal portion of the colon are sensitive to the secretory actions of enterotoxigenic E coli STa, and that the responses are mediated, in part, by release of prostaglandins.
Evaluation of travel and use as a risk factor for seropositivity to Ehrlichia risticii in horses of New York state
Authors: Atwill Edward R. , Mohammed Hussni O. , Lopez Jorge W. 
Published: January 2024

Abstract

Objective
To determine whether mean annual frequency and destination of equine travel was associated with exposure to Ehrlichia risticii and whether these associations were modified by horses’ place of residence.

Design
Cross-sectional study.

Sample Population
511 equine operations containing 2,587 horses were visited in New York state from a target population of 39,000 operations.

Procedure
Each horse was tested for serum antibodies against E risticii, using indirect fluorescent antibody. Information on the horse's travel history, farm's management practices, and surrounding ecology was obtained by personal interview and resource maps. Statistical analyses were performed on 2 cohorts of animals: all horses enrolled in the study and horses born on the property or that resided at least 4 years on the farm. Three countybased risk regions (RR) were identified by use of cluster analysis.

Results
Mean seroprevalence for each of the 3 RR was 2.4 (low risk), 8.5 (moderate risk), and 18.5% (high risk) for cohort 1 and 2.5, 8.0, and 18.4% for cohort 2. Among cohorts 1 and 2, pleasure riding and breeding trips were associated with exposure to E risticii, but horse residence (low, moderate, or high RR) was an effect modifier for these associations. Among cohort 1 and stratifying the analysis according to the RR for the travel destination, trail riding at low RR and trail riding at high RR were associated with exposure. Among cohort 2 and stratifying the analysis according to the RR for the travel destination, breeding trips were associated with exposure, and strong effect modification was present for horse residence (low, moderate, or high RR).

Conclusions
Only certain types of travel to specific RR were associated with higher risk of exposure to E risticii. In many instances, travel was not associated, or was associated, with a reduced risk of exposure.(Am J Vet Res 1996; 57: 272-277)
Serologic responses of cattle and other animals infected with Neospora caninum
Authors: Dubey J. P. , Lindsay D. S. , Adams D. S. , Gay J. M. , Baszler T. V. , Blagburn B. L. , Thulliez P. 
Published: January 2024

Abstract

Objective
To examine cross-reactivity among Neospora caninum and closely-related apicomplexans.

Design
Sera from animals were examined for antibody production to N caninum and cross-reactivity to Toxoplasma gondii.

Animals
Cattle were experimentally infected with 3 tissue cyst-forming protozoan parasites N caninum, T gondii, and Sarcocystis sp, and calves were monospecifically inoculated with the intestinal coccidia, Eimeria bovis and Cryptosporidium parvum. Similar studies were done in laboratory rabbits inoculated with N caninum, T gondii, Hammondia hammondi, and Sarcocystis sp. Additionally, sera were obtained from ewes, lambs, goats, sows, cats, rats, and mice inoculated with N caninum tachyzoites.

Procedure
The indirect fluorescent antibody (IFA) and ELISA antibody tests (cattle only) were used to examine reactivity to N caninum; the modified direct agglutination, Sabin-Feldman dye, and IFA tests were used to evaluate reactivity to T gondii.

Results
Serologic cross-reactivity among N caninum, T gondii, and Sarcocystis sp was none or minimal by the IFA test. There was some reactivity to N caninum by the use of ELISA in cattle inoculated with Sarcocystis sp.

Conclusions
The IFA test for N caninum was specific for the diagnosis of neosporosis in animals.(Am J Vet Res 1996;57:329-336)
Ultrasonography of the lungs, pleura, and mediastinum in healthy cows
Authors: Braun Ueli , Sicher Daniel , Pusterla Nicola 
Published: January 2024

Abstract

Objective
To describe the ultrasonographic appearance of the lungs, pleura, and mediastinum of cattle.

Design
Transcutaneous ultrasonography of the lungs and pleura was performed on the right and left sides of the thorax. The mediastinum was examined transesophageally.

Animals
50 healthy cows.

Procedure
The thoracic wall, pleura, and pulmonary surface were visualized on both sides of the thorax via transcutaneous ultrasonography. The cranial mediastinal lymph node, right azygos vein, aorta, and caudal vena cava were visualized via transesophageal ultrasonography.

Results
The layers of the thoracic wall appeared as narrow bands that varied in echogenicity. They were followed medially by an echogenic line that represented the costal and pulmonary pleurae. Reverberation artifacts were seen medial to the pleura. The pulmonary parenchyma could not be visualized ultrasonographically because of its air content. The cranial mediastinal lymph node appeared circular to oval. The right azygos vein was situated immediately adjacent to the cranial mediastinal lymph node. The aorta appeared circular to oval on cross-sectional view with an echogenic wall and an anechoic lumen. The caudal vena cava appeared as a tubular structure with an anechoic content and an echogenic wall.

Conclusion
Ultrasonography of the lungs, pleura, and mediastinum in healthy cows provides information that can be used as a reference when examining cattle with suspected disease of the thorax. (Am J Vet Res 1996; 57:432–438)