bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro depression of bovine lymphocyte function by treatment of cultured bovine lymphocytes with physiologic concentrations of hydrocortisone
Authors: Ojo-Amaize Emmanuel A. , Guidry Albert J. , Paape Max , Mayer Harald K. 
Published: February 2025

SUMMARY
The effect of hydrocortisone (hydrocortisone sodium succinate) on bovine lymphocyte blastogenesis in response to Staphylococcus aureus antigens and phytohemagglutinin was measured in vitro. Lymphocytes isolated from the blood of cows were treated for 6 to 8 days with physiologic hydrocortisone concentrations known to be inducible by environmental stress (10 ng/ml), acute clinical mastitis (25 ng/ml), or adrenocorticotropin treatment (45 ng/ml). All 3 concentrations of hydrocortisone caused a depression (P < 0.01) in lymphocyte blastogenesis in response to phytohemagglutinin and S aureus antigen extract. Hydrocortisone concentrations as low as 10 pg/ml caused a depression in the lymphocyte blastogenic response to phytohemagglutinin. Marked variation existed among cows in the normal response of their nontreated lymphocytes and in the degree of depression of lymphocyte function after the in vitro treatment with hydrocortisone.
Macrophage depletion experiments showed that the suppressive effect of hydrocortisone was not mediated by induction of suppressor macrophages. The data suggest that T-cell function was impaired directly by hydrocortisone treatment.
Effect of levamisole on immune function and reproductive performance in first-litter gilts
Authors: Purswell B. J. , Dawe D. L. , Brown John , Williams D. J. 
Published: February 2025

SUMMARY
First-litter commercial cross-bred gilts were treated with levamisole (1.5, 2.5, or 3.5 mg/kg of body weight) weekly during the last 4 weeks of gestation, because similar treatment of dairy heifers had improved postpartum maternal health and neonatal survival. In the gilts, differences in reproductive performance were not found on the basis of pig survival at birth, pig survival at weaning, birth weight, or weaning weight. Also, differences between treated and control gilts were not found in response of circulating lymphocytes to mitogen stimulation (phytohemagglutinin A, concanavalin A, and pokeweed mitogen). In all gilts, the lymphocyte response to mitogen stimulation was decreased during the first week after farrowing.
Aerosolized Micropolyspora faeni antigen as a cause of pulmonary dysfunction in ponies with recurrent airway obstruction (heaves)
Authors: Derksen F. J. , Robinson N. E. , Scott J. S. , Stick J. A. 
Published: February 2025

SUMMARY
Ponies with recurrent airway obstruction (principal ponies) and their controls were given aerosolized Micropolyspora faeni antigen via endotracheal tube during a period when the principal ponies were in disease remission. In both groups of ponies, we performed bronchoalveolar lavage (bal) and measured pulmonary function at base line, and 5 hours after aerosol administration of 30 ml of 0.9% NaCl solution or 30 ml of 1% w/v particulate M faeni antigen in 0.9% NaCl solution. In both groups of ponies, aerosolized M faeni antigen increased wbc count, neutrophil numbers, and albumin concentration in bal fluid, but macrophage numbers decreased. In the principal ponies, bal mast cell numbers were decreased 5 hours after administration of M faeni antigen. The M faeni antigen had no effect on the mechanical properties of the lungs or on gas exchange in the control ponies, but did increase respiratory frequency minute ventilation and pulmonary resistance, and decreased arterial oxygen tension in the principal ponies.
Changes in pulmonary function were apparent only in the principal ponies, which suggests that neutrophils, per se, do not cause pulmonary dysfunction and that M faeni may be one of the etiologic agents involved in chronic obstructive pulmonary disease.
Anemia of inflammation in dogs infected with Ehrlichia platys
Authors: Baker Dale C. , Gaunt Stephen D. , Babin Shirley S. 
Published: February 2025

SUMMARY
Ten adult male dogs were inoculated with Ehrlichia platys, and blood samples were collected throughout the infection to evaluate the hematologic changes with respect to serum biochemical analytes. All dogs developed a mild, normocytic, normochromic anemia by postinoculation day 7, with significantly (P < 0.05) decreased serum iron concentration and total iron-binding capacity. Stainable bone marrow iron appeared normal or increased throughout the infection. By postinoculation day 31, the pcv was not significantly different from the pretreatment value. All dogs became hypergammaglobulinemic, leukopenic, hypoalbuminemic, and hypocalcemic during the infection. These findings were compatible with the syndrome of anemia of inflammation.
Association of bovine respiratory syncytial virus with atypical interstitial pneumonia in feedlot cattle
Authors: Collins James K. , Jensen Rue , Smith George H. , Flack D. E. , Kerschen Robert , Bennett Bill W. , Jones Robert L. , Alexander A. F. 
Published: February 2025

SUMMARY
Thirty-three cattle with fatal respiratory tract disease were examined for gross and histologic lesions and for the presence of viral and bacterial agents in the lungs. Fifteen cattle had lesions characteristic of atypical interstitial pneumonia (aip), and 18 had other respiratoiy tract diseases, including infectious bovine rhinotracheitis, shipping fever pneumonia, bronchopneumonia, pulmonary abscess, and edema of the trachea. Gross necropsy findings in the cattle with aip were uncollapsed and emphysematous lungs; histopathologic findings included interstitial edema, thickening of alveolar walls, hyaline membrane formation, and hyperplasia of type-II pneumonocytes. The infective agents found in the lungs of the 33 cattle included bovine respiratory syncytial virus, bovine herpesvirus type 1, Pasteurella sp, mycoplasmas, and Corynebacterium pyogenes. Bovine respiratory syncytial virus was detected by use of immunofluorescence and immunoperoxidase on lung tissue sections; bovine herpesvirus type 1 was detected by these techniques and by isolation of the virus. Bovine respiratoiy syncytial virus was significantly (P = 0.01) associated with lesions of aip (11 of 15), compared with those of other respiratory tract diseases (5 of 18).
Neuromuscular and cardiovascular effects of atracurium administered to healthy horses anesthetized with halothane
Authors: Hildebrand S. V. , Arpin D. 
Published: February 2025

SUMMARY
Neuromuscular and cardiovascular effects of atracurium, a nondepolarizing neuromuscular blocking agent, were evaluated in 10 halothane-anesthetized adult horses. Hind limb digital extensor tension (hoof twitch) was measured with a strain gauge to quantitate the muscle relaxant effects of atracurium. Response of facial muscles was compared with hoof twitch. Five injections of atracurium were given. Initial mean (± sem) dosage of 0.07 ± 0.01 mg of atracurium/kg of body weight caused 98.6 ± 0.8% reduction of the preinjection hoof twitch. Subsequent dosages of 0.04 ± 0.003 mg/kg induced a degree of relaxation similar to that induced by the initial dose. Duration of paralysis from maximal effect to 10% recovery of twitch was 12.2 ± 1.5 minutes for the first injection. This was significantly (P < 0.05) different from subsequent paralysis periods, which lasted approximately 7 minutes. The 10% to 75% recovery time after all injections was similar—approximately 16 minutes. The facial muscles were less affected objectively by atracurium than was the hind limb. Atracurium did not cause cardiovascular changes.
When the hoof twitch had recovered to 95% of its tension before atracurium administration, 0.5 mg of edrophonium/kg, was given to antagonize neuromuscular blockade. Within 5 minutes of edrophonium administration, twitch tension exceeded that measured before atracurium administrations. Within 2 minutes of edrophonium administration, blood pressure began to increase and continued to increase approximately 10 mm of Hg above the value measured before edrophonium administration. Heart rate was not affected by edrophonium. Other muscarinic side effects of edrophonium were not observed.
Of the 10 horses, 9 had good, unremarkable recovery to standing position. One horse had a violent recovery period.
Enumeration of T and B lymphocytes in bovine leukemia virus-infected cattle, using monoclonal antibodies
Authors: Williams Diana L. , Amborski Grace F. , Davis William C. 
Published: February 2025

SUMMARY
Monoclonal antibodies and microfluorimetry were used to determine the absolute number of B and T lymphocytes in the blood of bovine leukemia virus (blv)-infected cows. The blood lymphocyte populations from blv-infected cows were significantly higher than those from blv-negative cows. The increase in the lymphocyte population in 3 blv-infected nonlymphocytotic cows was attributed to a significant increase in the number of T lymphocytes; in 3 blv-infected persistently lymphocytotic cows, the increase was attributed to a significant increase in the number of B and T lymphocytes. One persistently lymphocytotic cow had a high lymphocyte count, and lymphocytes from this cow contained cells that appeared to stain with markers specific for bovine B and T lymphocytes. We concluded that infection of cattle with the B-cell lymphotropic retrovirus, blv, not only affected B cells, but also T cells.
Age-related variations in serum concentrations of the third component of complement in swine
Authors: Tyler Jeff W. , Cullor James S. , Osburn Bennie I. , Parker Kent 
Published: February 2025

SUMMARY
Single radial immunodiffusion was used to determine the concentration of the third component of complement (C3) in serum from swine in the following age groups; 36 to 60 hours (neonates), 6 to 7 weeks (weanlings), 4 to 5 months (adolescents), and > 1 year (adults). Mean serum C3 concentrations, expressed as the percentage of pooled reference sera from 15 adult swine for the 4 groups were 23, 123, 119, and 98%. With the exception of mean values for weanlings and adolescents, all comparisons of group means were significantly different. Regression models were developed to estimate serum C3 concentration in neonates as a function of litter size, birth weight, and total serum IgG concentration. Increases in birth weight and litter size were accompanied by increased serum C3 concentration, possibly reflecting ontogenic variation of the complement system at the end of gestation. Passive transfer of colostral immunoglobulins, as measured by total serum IgG concentration, was inversely related to serum C3 concentration in neonatal swine, suggesting that colostral absorption of C3 has minimal impact on complement activity in neonatal swine.
An immunoperoxidase method of detecting respiratory syncytial virus antigens in paraffin sections of pneumonic bovine lung
Authors: Bryson David G. , Cush P. F. , McNulty M. S. , Platten M. , Allan G. M. 
Published: February 2025

SUMMARY
Using an avidin-biotin-peroxidase complex immunoperoxidase staining method, respiratory syncytial virus (rsv) antigen was demonstrated in glutaraldehyde-fixed, paraffin-processed lung sections from calves with induced rsv pneumonia. The virus also was detected in formalin-fixed, paraffin-processed lung sections from calves with naturally occurring rsv pneumonia.
Specific immunoperoxidase staining was detected within the cytoplasm of epithelial cells and syncytia in small bronchi, bronchioli, and alveoli. Staining also was detected within exudates in airway lumina and in mononuclear and multinucleate cells within alveolar lumina. Optimal intensity of staining was achieved by proteolytic enzyme treatment of lung sections, using 0.1% pronase and overnight incubation in diluted primary antiserum. The distribution of antigen had a close correlation with presence of lesions. Antigen-staining patterns were similar in lung tissue from calves with naturally occurring and induced rsv disease.
Postweaning diarrhea in swine: Effects of oxytetracycline on enterotoxigenic Escherichia coli infection
Authors: Sarmiento Juan I. , Moon Harley W. 
Published: February 2025

SUMMARY
Investigators have found that oxytetracycline decreases the adhesion of K88+ Escherichia coli to intestinal epithelial cells in vitro. This occurs with oxytetracycline-sensitive E coli at drug concentrations less than those required to prevent growth and with E coli that are resistant to the drug. We conducted experiments to determine whether oxytetracycline alters the disease caused by an oxytetracycline-resistant K88+ enterotoxigenic strain of E coli. Oxytetracycline-treated pigs (inoculated with K88+ E coli) did not differ from nontreated pigs in the incidence or severity of diarrhea, nor in the shedding of K88+ E coli. However, during recovery, weight gain by treated pigs was slower than that of nontreated pigs. The control pigs were not inoculated with E coli, and they remained clinically normal. Oxytetracycline-treated controls gained weight faster than nontreated controls. Some controls were genetically resistant to K88+ E coli, others were susceptible. The K88-resistant oxytetracycline-treated controls gained weight faster than the K88-susceptible oxytetracycline-treated and nontreated controls.
Pathogenesis of experimentally induced feline immunodeficiency virus infection in cats
Authors: Yamamoto Janet K. , Sparger Elizabeth , Ho Esther W. , Andersen Philip R. , O'Connor Thomas P. , Mandell Carol P. , Lowenstine Linda , Munn Robert , Pedersen Niels C. 
Published: February 2025

SUMMARY
Feline immunodeficiency virus (fiv; formerly, feline T-lymphotropic lentivirus) is a typical lentivirus resembling human and simian immunodeficiency viruses in morphologic features, protein structure, and reverse transcriptase enzyme. It is antigenically dissimilar, however. The virus is tropic for primary and permanent feline T-lymphoblastoid cells and Crandell feline kidney cells. The virus did not grow in other permanent feline non-lymphoblastoid cells that were tested, or in lymphoid and non-lymphoid cells from man, dogs, mice, and sheep.
During short-term inoculation studies in cats, the feline immunodeficiency-like syndrome found in nature was not experimentally induced, but a distinct primary phase of infection was observed. Fever and neutropenia were observed 4 to 5 weeks after inoculation; fever lasted several days, and neutropenia persisted from 1 to 9 weeks. Generalized lymphadenopathy that persisted for 2 to 9 months appeared at the same time.
Antibodies to fiv appeared 2 weeks after inoculation and then plateaued. Virus was reisolated from the blood of all infected cats within 4 to 5 weeks after inoculation and persisted indefinitely in the face of humoral antibody response. Virus was recovered from blood, plasma, csf and saliva, but not from colostrum or milk.
Contact transmission was achieved slowly in one colony of naturally infected cats, but not between experimentally infected and susceptible specific-pathogen-free cats kept together for periods as long as 4 to 14 months. The infection was transmitted readily, however, by parenteral inoculation with blood, plasma, or infective cell culture fluids. In utero and lactogenic transmission were not observed in kittens born to naturally or experimentally infected queens.
Lymphadenopathy observed during the initial stage of fiv infection was ascribed to lymphoid hyperplasia and follicular dysplasia. A myeloproliferative disorder was observed in 1 cat with experimentally induced infection.
Antigenic relationship between Mycobacterium paratuberculosis and Mycobacterium avium
Authors: Camphausen Raymond T. , Jones Robert L. , Brennan Patrick J. 
Published: February 2025

SUMMARY
Four prototype strains of Mycobacterium paratuberculosis contained the type-specific glycopeptidolipid antigen of serovar 8 of the M avium complex. This glycolipid was distinguished by a 4,6-(1′-carboxyethylidene)-3-O-methyl-β-d-glucopyranosyl terminal unit. Of 59 low-passage, field isolates of M paratuberculosis, 2 contained this antigen, and these 2 isolates were indistinguishable from M avium serovar 8. However, most M paratuberculosis isolates had no characteristic surface glycopeptidolipid. Seemingly, M paratuberculosis, long regarded as a single species and the causative agent of bovine paratuberculosis, is not a homogeneous taxon. Most isolates obtained from infected ruminants may be antigenically defective, variants of M avium and, thereby, more successful pathogens.
Studies on the ability of a 98-kilodalton pseudorabies virus diagnostic antigen to detect latent infections induced by low-dose exposure to the virus
Authors: Mc Ginley M. J. , Platt K. B. 
Published: February 2025

SUMMARY
The effect of low-dose challenge of immunity with pseudorabies virus (prv) on subunit-vaccinated pigs was studied in 2 experiments. In the first experiment, we studied the effect of challenge dose on the antibody response to an early excreted 98-kilodalton prv-glycoprotein that was used as a diagnostic antigen in the elisa. In the second experiment, we studied the effect of low doses of virus on the establishment of latent infections in subunit-vaccinated pigs.
The relationship of virus exposure dose and vaccine dose to the response of pigs to diagnostic antigen was studied in 18 pigs. Two groups of 3 pigs were vaccinated with a total of 200 μg of a lectin-derived prv subunit vaccine over a 5-week period. Two groups of 3 pigs were similarly vaccinated with a total of 100 μg. Two groups of 3 pigs served as nonvaccinated controls. One group of pigs from each of the preceding categories was intranasally exposed to 106.0 and 102.7 plaque-forming units (pfu) of virus. Antibody to diagnostic antigen was detected by the elisa and radioimmunoprecipitation 3 to 7 days earlier in pigs exposed to 106.0 pfu, demonstrating that the size of the virus challenge dose affects the antibody response to diagnostic antigen.
The establishment of latent infections by low prv doses and the ability to detect these infections was studied in 10 subunit-vaccinated pigs. Each pig was intranasally exposed to 102.3 pfu of virus (day 0). The serum virus-neutralizing antibody titer of these pigs increased to their highest level 14 to 21 days after exposure and then steadily decreased through day 113, indicating absence of viral recrudescence. All pigs were treated with dexamethasone for 4 consecutive days, beginning on day 113. Latent infections were identified in 8 of 10 pigs on the basis of recovery of virus and/or 2 log2 or greater increases in serum virus-neutralizing titer. Antibody to diagnostic antigen was initially detected in the 8 latently infected pigs on day 14 or 21 and continued to be detected through days 21, 46, 53, 110, and 113 in 1, 2, 1, 1, and 3 pigs, respectively. The antibody titer to diagnostic antigen increased in 6 of the 8 latently infected piers after dexamethasone treatment. However, antibody to diagnostic antigen was not detected by elisa in the remaining 2 latently infected pigs, despite increases in serum virus-neutralizing titers in both pigs and the recovery of reactivated virus from one pig. The failure to consistently detect antibody to diagnostic antigen in latently infected pigs suggests that diagnostic tests using nonvaccine diagnostic antigen may be suitable only for detecting infections in vaccinated herds, but not in individual pigs.
Prevalence and characterization of Staphylococcus aureus in young goats
Authors: de Centorbi O. N. P. , de Cuadrado A. M. A. , de Carrizo S. C. C. , de Milán M. C. C. , Giménez D. F. , Bergdoll M. S. 
Published: February 2025

SUMMARY
Thirty-six Staphylococcus aureus isolates recovered from 35 of 204 young goats at slaughter were characterized. All isolates were susceptible to cephalothin, clindamycin, chloramphenicol, gentamicin, kanamycin, and amikacin. All but 2 were susceptible to erythromycin and tetracycline, and 19 and 20 were susceptible to penicillin and ampicillin, respectively. Thirteen isolates were classified as biotype A, 9 isolates were classified as biotype B, 8 isolates were classified as biotype C, and 6 isolates were classified as intermediate between B and C or were not biotypable. Six biotype A isolates were enterotoxigenic; 4 produced enterotoxin B, 1 produced enterotoxin C, and 1 produced enterotoxin D. Two biotype B strains produced enterotoxin B, and all 8 biotype C isolates produced enterotoxin C and the toxic shock syndrome toxin-1.
Electromyographic evaluation of conduction time and velocity of the recurrent laryngeal nerves of clinically normal dogs
Authors: Steiss Janet E. , Marshall Arvle E. 
Published: February 2025

SUMMARY
In 25 adult dogs of various breeds, recurrent laryngeal nerve fibers were electrically stimulated at 2 points along their extralaryngeal course. Evoked compound muscle action potentials were recorded in the ipsilateral intrinsic laryngeal muscles, using a percutaneous needle electrode. Latencies, amplitudes, and durations were measured. Latencies were correlated with neck length (r = 0.88 on left and 0.82 on right). Five of the dogs were euthanatized, and the nerve length between the 2 stimulating needle electrodes was measured; calculated conduction velocities (mean ± sd) were 55 ± 6 m/s (left) and 57 ± 6 m/s (right). In 38 additional canine cadavers, the lengths of the exposed left and right recurrent laryngeal nerves were correlated with neck length (r = 0.44 on left and 0.56 on right). A linear regression model is proposed for predicting normal latencies, despite variations in neck length among different breeds of dogs.
Sensitivity and specificity of latex agglutination tests used to identify Streptococcus agalactiae and Staphylococcus aureus isolated from bulk tank milk
Authors: Hogan Joseph S. , Smith K. Larry , Todhunter Deborah A. , Schoenberger Pam S. 
Published: February 2025

SUMMARY
Comparisons were made among rapid latex agglutination tests and conventional biochemical tests used to identify Streptococcus agalactiae and Staphylococcus aureus. Ninety-eight streptococci and 149 staphylococci isolated from bulk tank milk were tested. Sensitivity and specificity for the latex agglutination test used for identification of Str agalactiae were 97.6 and 98.2%, respectively. Sensitivity and specificity for the latex agglutination test used for identification of S aureus were 90.2 and 67.5%, respectively. Of 25 staphylococci considered false-positive by the latex agglutination test, 14 (56%) were considered tube coagulase-positive. Fifteen staphylococci considered false-positive by latex agglutination test had biotypes representative of S hyicus or S xylosus.
Efficacy of ivermectin in paste and injectable formulations against microfilariae of Onchocerca cervicalis and resolution of associated dermatitis in horses
Authors: French Dennis D. , Klei T. M. , Foil Carol S. , Miller R. I. , Foil L. D. , Chapman M. R. , McClure J. J. 
Published: February 2025

SUMMARY
The efficacy of a single dose of ivermectin (0.2 mg/kg), in injectable or paste formulations, against microfilariae of Onchocerca cervicalis and associated skin lesions was evaluated in 20 naturally infected horses during midsummer months in Louisiana. All horses had clinical signs of dermatitis of the ventral midline and/or limbs, shoulders, thorax, and withers. Efficacy was monitored at 21, 42, and 63 days after treatment. Procedures done at these intervals included microfilarial counts of 6-mm skin biopsy specimens of affected ventral midline, grading of gross lesions, and photography and histologic assessment of ventral midline biopsy specimens. Microfilarial numbers were reduced to 0 by 21 days after treatment in all but one horse. Active lesions improved or were resolved completely by 63 days after treatment. Total inflammation, as judged by histologic methods, was reduced in all horses by 63 days after treatment, but there was a residual population of inflammatory cells in all horses. Adverse reactions after treatment were not observed in any of the horses.