bluuebunny/crossref_metadata_2025_split huggingface dataset:
Responses of horses vaccinated with avirulent modified-live equine arteritis virus propagated in the E. Derm (NBL-6) cell line to nasal inoculation with virulent virus
Authors: McCollum William H. 
Published: February 2025

SUMMARY
Nineteen horses with no prior experience with equine arteritis virus (eav) were inoculated im with an avirulent live-virus vaccine against equine viral arteritis; the vaccinal virus had been passaged serially 131 times in primary cell cultures of equine kidney, 111 times in primary cell cultures of rabbit kidney, and 16 times in an equine dermis cell line (eav HK-131/RK-111/ED-16). Three or 4 of the vaccinated horses each, along with appropriate nonvaccinated controls, were inoculated nasally with virulent eav at each of months 3, 6, 9, 12, 18, and 24 after they were vaccinated. The following was concluded:

(1)Vaccination did not induce clinical signs of disease in any horse and, thus, seemed safe for use in the field.

(2)All vaccinated horses (n = 19) developed serum-neutralizing antibodies to eav.

(3)Fourteen of the vaccinated horses were completely protected from clinical arteritis when exposed to large doses of virulent eav. Four were partially protected, and one had little or no protection. Six of 13 nonvaccinated horses died of acute arteritis, and the remaining 7 horses experienced severe signs of disease, but survived the infection.

(4)All horses (n = 32), whether vaccinated or not, became infected when inoculated nasally with virulent eav. Virus was recovered from 17 of the 19 vaccinated horses, and all 19 had a secondary humoral immune response. The duration and severity of thermal reaction and persistence of virus were more transitory in vaccinated horses than in the nonvaccinated controls.

(5)Protection afforded by this vaccine can persist for at least 24 months, the maximal time after horses were vaccinated that immunity was challenged in the present study.

(6)The more pronounced clinical and virologic responses which were seen among horses given the vaccine eav HK-131/RK-111/ED-16 and subsequently inoculated with virulent eav, when compared with the responses in horses given the vaccine eav HK-131/RK-80 or HK-131/RK-111, indicated that vaccine eav HK-131/RK-111/ED-16 had become more attenuated as a result of the further serial passage in the equine dermis cell line.
Immunohistochemical staining patterns of canine eyes affected with chronic superficial keratitis
Authors: Eichenbaum J. D. , Lavach J. D. , Gould D. H. , Severin G. A. , Paulsen M. E. , Jones R. L. 
Published: February 2025

SUMMARY
Fourteen limbal biopsy specimens from 11 dogs with chronic superficial keratitis (csk) were examined histologically and immunohistochemically. Ten of the 14 specimens had corneal epithelial hyperplasia and/or atrophy. Eleven of the 14 specimens had thickened epithelial basement membranes. Each specimen had cellular infiltration and lamellar disruption of the stroma.
An avidin-biotin immunoperoxidase complex stain was used to detect immunoglobulin (Ig) deposition. Twelve of the 14 specimens stained positive for Ig. The staining pattern was consistent and characterized by diffuse deposition of stain in the superficial conjunctival stroma near the limbus. Four of the 12 Ig-positive specimens also stained positive in the superficial corneal stroma with 1 of these 4 also staining positive along the epithelial cell basement membrane.
The diffuse pattern of stain deposition and the absence of staining of specific epithelial structures indicated that csk is not a classical autoimmune disease similar to any disease in the pemphigus group or similar to systemic lupus erythematosus. Although the results may implicate csk as an immune-mediated disease, nonspecific factors could not be ruled out.
Immunotoxic effects of T-2 toxin on cell-mediated immunity to listeriosis in mice: Comparison with cyclophosphamide
Authors: Cornier Donald E. , Ziprin Richard L. 
Published: February 2025

SUMMARY
Immunotoxic effects of T-2 toxin and cyclophosphamide on cell-mediated resistance were evaluated in mice exposed to Listeria monocytogenes infection. Mice were inoculated intraperitoneally with 4.0 × 105 (ld50) or 4.0 × 104 (nonlethal) L monocytogenes and were treated with 4.0 mg of T-2 toxin/kg of body weight or 180 mg of cyclophosphamide/kg. The immunosuppressive effect of the toxin and cyclophosphamide was indicated by the rapid growth of Listeria and significant (P < 0.005) increases in mortality because of listeriosis. Necrosis and depletion of lymphoid tissue, lymphopenia, and significant (P < 0.005) decreases in the influx and number of lymphocytes and macrophages occurred in Listeria-elicited peritoneal exudates and at sites of infection in the liver and spleen of the toxin- and cyclophosphamide-treated mice. Immunotoxic effects of T-2 toxin and cyclophosphamide were comparable and attributed primarily to the depletion of T lymphocytes and the subsequent failure of surviving immunologically committed T cells and T-cell dependent immune-activated macrophages to clear the host of bacteria.
Effects of estrone infusion on secretion of F series prostaglandins and on function of the corpus luteum during late gestation in cattle
Authors: Pimentel C. A. , Vijayakumar R. , Weston P. G. , Pimentel S. M. , Wagner W. C. , Hixon J. E. 
Published: February 2025

SUMMARY
Catheters were surgically implanted in the carotid artery, jugular vein, and middle uterine vein of 8 cows at 245 days of gestation. Four cows were given 4 mg of estrone/hour via continuous jugular infusion from 0800 hours on day 246 of gestation through 0800 hours on day 250 of gestation; the remaining 4 cows (controls) were given the vehicle for estrone at 10 ml/hour for the same period. Blood samples were collected from the carotid artery every 3 hours during the infusion. Samples were collected hourly from the middle uterine vein from 0 through 8, 54 through 66, and 112 through 120 hours of the infusion periods. After completion of the infusion, corpora lutea were enucleated and blood samples were collected from the carotid artery and uterine vein at hourly intervals for an additional 8 hours. Dispersed cell preparations of the corpora lutea were incubated with and without luteinizing hormone (lh) or dibutyryl cyclic adenosine monophosphate (dbcAMP).
Circulating concentrations of unconjugated and conjugated estrone and estradiol-17β were higher (P < 0.05) in the group infused with estrone than in the vehicle-infused group. Mean and base-line concentrations of F series prostaglandins (pgf) for each blood collection period tended to increase (P < 0.10) during infusion with estrone, but not during infusion with vehicle. After luteectomy, mean and base-line concentrations of pgf also tended (P < 0.10) to be greater in the estrone-infused cows than in the control cows, but a surge in pgf concentrations due to removal of the ovarian source of progesterone did not develop. Long intervals (14 to 16 days) between enucleation of corpora lutea and calving and a more rapid (P < 0.05) rate of decrease in progesterone concentrations in the systemic arterial circulation than in the uterine venous circulation after luteectomy indicated that the placenta may have secreted progesterone during the course of the study.
Corpus luteum weight and systemic and luteal concentrations of progesterone were not affected by infusions with estrone. Although the addition of lh or dbcAMP did increase the synthesis rate of progesterone by incubated luteal cells from 2 cows in each group, the response of luteal cells to lh or dbcAMP was not different between the groups. Secretory pulses of pgf were detected, but estrone treatment did not affect their frequency.
High-frequency jet ventilation during pneumothorax in dogs
Authors: Bjorling Dale E. , Whitfield Jeff B. 
Published: February 2025

SUMMARY
Pneumothorax (45 ml of N/kg of body weight insufflated into the pleural space) in anesthetized dogs ventilated with air caused a significant (P < 0.05) increase in pleural pressure, central venous pressure, capillary wedge pressure, and venous admixture. Cardiac index (ci) and arterial O2 tensions were decreased. Ventilation with 100% O2 increased arterial O2 tensions, but did not affect calculated intrapulmonary shunting of blood or ci. Application of 10 cm of H2O-positive end-expiratory pressure in the presence of pneumothorax during positive-pressure ventilation and high-frequency jet ventilation reduced intrapulmonary shunting of blood, which remained higher than control values, and caused a further decrease in ci. Cardiopulmonary function during pneumothorax in anesthetized dogs was more profoundly affected by the application of positive end-expiratory pressure than by the form of mechanical ventilation.
Pathophysiology of small testes in beef bulls: Relationship between scrotal circumference, histopathologic features of testes and epididymides, seminal characteristics, and endocrine profiles
Authors: Veeramachaneni D. N. Rao , Ott R. S. , Heath E. H. , McEntee K. , Bolt D. J. , Hixon J. E. 
Published: February 2025

SUMMARY
Tissue sections from testes and epididymides obtained from 17 young beef bulls with scrotal circumference (sc) between 27 and 40.5 cm were studied to determine whether small testes were a manifestation of lesions or a result of less, but otherwise normal, seminiferous epithelium. The sc correlated negatively with the estimates of germinal epithelial loss and positively with seminiferous epithelial area. Four bulls with sc < 30 cm had severe lesions in their testes. Hypoplastic tubules were characterized by Sertoli's cells only with no evidence of germinal cells. Loss of germinal cells, leaving vacuolated epithelium and atrophy, were observed in degenerated tubules. Hyperplasia of Leydig's cells was observed in the vicinity of Sertoli's cell-only tubules, resulting either from degeneration or hypoplasia, and atrophy of Leydig's cells was associated with tubules devoid of Sertoli's cells. These findings indicated that Sertoli's cells may produce a factor(s) required for maintenance and regulation of Leydig's cell function. Epididymal epithelium, especially in the head, had regressed in bulls with hypoplastic and degenerative changes in their testes. Decreased sperm concentration and motility and an increased frequency of morphologic defects were observed in the 4 bulls with testicular lesions and regressed epididymal epithelium. Blood plasma profiles of cortisol, follicle-stimulating hormone, luteinizing hormone, and testosterone were determined in the 4 bulls with sc < 30 cm and 10 of the 13 bulls with sc > 30 cm. There were no statistically significant (P > 0.1) differences in the responses to exogenous gonadotropin-releasing hormone or base-line patterns of blood plasma follicle-stimulating hormone and luteinizing hormone between the 2 groups. However, in the bulls with sc < 30 cm, the mean concentration of testosterone was lower, whether spontaneous (P < 0.05) or exogenous gonadotropin-releasing hormone induced (P < 0.1). The fact that these bulls were not deficient in gonadotropins indicated that Leydig's cell function was impaired by local factors, either the factors that caused the tubular damage or those consequent to the tubular damage.
Endocrinologic, hematologic, and heart rate changes in swimming horses
Authors: Garcia M. C. , Beech Jill 
Published: February 2025

SUMMARY
Two identical experiments, using Standardbred and Thoroughbred horses (experiment A, n = 31; experiment B, n = 17) on a swimming regimen, were performed 1 week apart to evaluate short-term heart rate, hematologic, and endocrinologic changes. Horses were placed in 4 categories based on duration of swimming (1 to 5, > 5 to 10, > 10 to 15, and > 15 minutes). Heart rate, pcv, and plasma concentrations of total protein, cortisol triiodothyronine, thyroxine, insulin, and glucose of each horse were evaluated before, immediately after, and 1 hour after swimming. For experiment A, there was a main effect of time of sampling on pcv, total protein, triiodothyronine, thyroxine, and insulin. There was a main effect of duration of swimming on insulin concentration and an interaction of duration of swimming and time of blood collection on heart rate and cortisol concentration. For experiment B, there was a main effect of time of blood collection on all the variables except glucose.
Flow cytofluorometric characterization of bovine blood and milk leukocytes
Authors: Hageltorn M. , Saad M. Alaa 
Published: February 2025

SUMMARY
Flow cytometry and sorting proved to be a rapid method that facilitated the identification of different leukocyte populations in bovine blood and milk. After briefly incubating whole blood and milk samples in a hypotonic phosphate buffer, containing supravital acridine orange, 5 classes of leukocytes were found in the blood (lymphocytes, neutrophils, eosinophils, basophils, and monocytes) and 4 in the milk (lymphocytes, neutrophils, monocytes, and macrophages) by flow cytometry. Cells were morphologically identified by fluorescent microscopy after flow cytometric sorting and by light microscopy after Papanicolaous staining. Udder parenchymal and ductal tissue cells (secretory and epithelial cells) were not found in the milk samples evaluated. Large differences in the total and differential cell counts were found in the different milk secretions.
Effects of aflatoxin on the growth performance and immune responses of weanling swine
Authors: Panangala V. S. , Giambrone J. J. , Diener U. L. , Davis N. D. , Hoerr F. J. , Mitra A. , Schultz R. D. , Wilt G. R. 
Published: February 2025

SUMMARY
Aflatoxin (af)-contaminated ground com was mixed with a commercial swine ration to yield 2 concentrations (500 mg of afb1/kg of feed [A] and 300 mg of afb1/kg [B]) and was fed to 2 groups of pigs. Groups A and B were fed the af-containing ration, whereas control group C was fed the same commercial ration mixed with ground corn devoid of af. A comparative analysis of the average weight gain per pig in each of the treatment groups, compared with that in the control group, indicated a significantly (P < 0.01) greater weight gain in the control group. The average feed conversion rate was also significantly (P < 0.01) lower in group A pigs, compared with that in the control group. The humoral immune response to Erysipelothrix rhusiopathiae, measured by enzyme-linked immunosorbent assay, did not reveal a significant difference among groups; there were no consistent differences observed in the proliferative responses of lymphocytes to mitogens. In contrast, a significant (P < 0.05) reduction in complement titers was observed, whereas an increase in serum immunoglobulin G and M values occurred in the af-treated group A, compared with that in group C. Gross enlargement of the liver, substantiated by histologic evidence of toxic damage to the hepatic parenchyma, revealed that af at concentrations of 500 mg/kg of feed was toxigenic and produced an adverse effect on the growth rate, feed efficiency, and general well-being of young pigs.
Delta-aminolevulinic acid dehydratase (EC4.3.1.24) activity in erythrocytes from cattle administered low concentrations of lead acetate
Authors: Bratton Gerald R. , Childress Marilyn , Zmudzki Jan , Womac Carolyn , Rowe Loyd D. , Tiffany-Castiglioni Evelyn 
Published: February 2025

SUMMARY
Four different age groups of cattle, which had never been exposed to Pb, were used to determine normal age-related values for erythrocyte δ-aminolevulinic acid dehydratase (alad) activity. Acute or chronic Pb intoxication was experimentally induced in young calves, and their alad values were compared with the normal values. Results indicated that alad of normal bovine erythrocytes increased 2- to 3-fold from 1 week to 9 weeks of age and then slowly returned to the initial (1 week old) value by 9 months of age. Erythrocyte alad from cattle ≥ 9 months old was uniform. Because of the age-related changes in normal alad of cattle < 9 months old, the age of an animal should be carefully established and age-matched controls evaluated simultaneously when alad is used to assess calves suspected of having Pb poisoning. A significant negative correlation was found between blood Pb concentration and alad during the first 24 hours after the initial administration of Pb, indicating a high sensitivity of erythrocyte alad to Pb. However, when blood Pb concentrations reached 50 μg/dl, alad did not change further. Because single ingestions of Pb can raise blood Pb concentrations > 50 μg/dl, alad appears to have little value in differentiating acute from chronic Pb intoxication.
Within 7 days after Pb administration ceased, alad did not increase significantly, even when calves were given calcium ethylenediaminetetraacetic acid (CaNa2EDTA); however, blood Pb concentration decreased by 50%. The rapid change in blood Pb concentration gave a false indication of a positive treatment effect when no real effect was detected by alad. These findings indicated that alad may be more useful than blood Pb concentration for estimating the effectiveness of chelation treatment for Pb intoxication because the animal would have to be almost completely deleaded before alad values return to normal. The method of storing blood samples was critical to the accuracy of determining alad. Rapid freezing in liquid nitrogen for up to 10 days, refrigeration for up to 6 days, storage in wet ice for 3 days, or storage at room temperature (22 C) for 3 days adequately preserved alad, whereas freezing in a home freezer for 3 days resulted in a 50% loss of alad.
Histochemical changes in skeletal muscles of four male horses with neuromuscular disease
Authors: Andrews F. M. , Spurgeon T. L. , Reed S. M. 
Published: February 2025

SUMMARY
Skeletal muscle biopsy specimens were taken from 4 male horses with neuromuscular disease such as myotonia congenita, chronic myositis, exertional rhabdomyolysis, and shivers. Histologic and histochemical techniques were used to evaluate skeletal muscle morphologic features and fiber-type population, size, and area, as well as muscle enzyme activities (acid phosphatase, alkaline phosphatase, and esterase). A histochemical and histologic profile were described for each muscle biopsy specimen.
Induction of mycoplasmosis in goat kids by oral inoculation with Mycoplasma mycoides subspecies mycoides
Authors: DaMassa A. J. , Brooks D. L. , Holmberg C. A. 
Published: February 2025

SUMMARY
A one-time, orally administered dose of ≥ 1 × 106 colony-forming units of Mycoplasma mycoides subspecies mycoides was sufficient to induce clinical mycoplasmosis (n = 37) terminating in fatal mycoplasmemia in 73% (37 of 51) of the clinically affected kids. The pathogen was isolated from the blood samples as early as 24 hours after oral inoculation; hot, swollen joints frequently were evident by 4 or 5 days after exposure. Pyrexia (to 42.3 C) was detected in about 95% (35 of 37) clinically affected kids, although about 5% (2 of 35) died peracutely without fever or other premonitory signs. At necropsy, the cardinal lesions were a fibrinopurulent polyarthritis and red, patchy to diffuse areas of consolidation in 1 or more lung lobes. At death, usually within 4 to 16 days after oral inoculation, the concentration of M mycoides subspecies mycoides in the blood was 1 × 106 to 1 × 107 colony-forming units/ml.
Histologically, the kids had diffuse fluid leakage into pulmonary alveoli and to a lesser extent into small vessels of various other organs. Fibrinocellular thrombi of terminal occurrence were occasionally present in various organs. The meningeal, pleural, and peritoneal surfaces had vascular leakage and a minimal perivascular accumulation of leukocytes.
The disease was contagious. Of 14 noninoculated control kids in close confinement with affected kids, 8 (57%) developed mycoplasmosis in 7 to 15 days and died of mycoplasmemia. The remaining 5 noninoculated kids remained healthy, as did noninoculated kids that were kept isolated from affected kids.
Antagonism of xylazine-induced depression of shuttle-avoidance responses in dogs by administration of 4-aminopyridine, doxapram, or yohimbine
Authors: Schaffer David D. , Hsu Walter H. , Hopper David L. 
Published: February 2025

SUMMARY
The effectiveness of 4-aminopyridine, doxapram, or yohimbine as antagonists against xylazine-induced cns depression in dogs was evaluated and compared, using the 2-way shuttle-avoidance paradigm. All drugs were given iv to 5 male dogs trained to avoid mild shock by jumping over a hurdle within 10 s after initiation of an audible tone. At dosages of 1 and 2 mg/kg of body weight, xylazine abolished or significantly decreased the mean number of avoidance responses and significantly increased the mean latency of avoidance responses.
The analeptic 4-aminopyridine (0.5 mg/kg) did not significantly antagonize xylazine in all dogs. One dog convulsed both times it was given xylazine followed by 4-aminopyridine, but did not convulse when given either drug alone.
Doxapram (5.5 mg/kg), a short-acting analeptic and respiratory stimulant, was only partially effective in antagonizing xylazine, and its antagonistic actions were brief.
Yohimbine (0.1 mg/kg), an α2-adrenoreceptor-blocking agent, was superior to 4-aminopyridine and doxapram in its ability to antagonize xylazine-induced cns depression. Yohimbine consistently increased the mean number of avoidance responses to the maximum of 8 and consistently decreased the mean latency of avoidance responses to control values in dogs given 1 or 2 mg of xylazine/kg. In dogs given 2 mg of xylazine/kg, yohimbine was significantly more effective than 4-aminopyridine or doxapram in its ability to increase the mean number of avoidance responses and decrease the mean latency of avoidance responses.
Results of the present study indicated that yohimbine was superior to 4-aminopyridine and doxapram in sustaining the reversal of xylazine-induced suppression of avoidance responses in dogs and that xylazine’s suppression of the avoidance responses may be mediated by α2-adrenoreceptors.